Sciencemadness Discussion Board - P2P from recycled styrene?

P2P from recycled styrene?

womble - 31-1-2007 at 23:05

From my limited reading on the subject, I have noted the capacity for oxidation type reactions to proceed rapidly to the carboxylic acid derivative of the aldehyde. Thus, I propose a novel route to P2P.

1. Styrene can be reclaimed from styrene & polystyrene containers as per the following patent.

http://www.patentstorm.us/patents/6500872-claims.html

(Limonene is suggested as the organic solvent; there is another that suggests using styrene itself – although you probably couldn’t unless you already had some?)

2. Styrene can be oxidised to its epoxy derivative as per the following patent (gas-phase/pipe bomb).

http://www.patentstorm.us/patents/4894467-description.html

(One of the problems with which process is over-oxidisation)

3. Styrene Oxide / epoxide shows a tendency when being studied to isomerise to phenylacetaldehyde.

http://www.rsc.org/delivery/_ArticleLinking/DisplayArticleFo...

Surely if it has a tendency to do so, this could be exploited ie. Intentionally inducing isomerisation to the aldehyde (seems to be a product of oxidation anyway).

4. If the styrene oxide, when subjected to further oxidisation, forms the aldehyde, further oxidisation would, logically, form the carboxylic acid, phenylacetic acid?

http://www.erowid.org/archive/rhodium/chemistry/p2pol.styren...

(This is provided as it shows the linkages of the styrene oxide, I really don’t want to fuck with grignard’s)

5. Phenylacetic acid and acetic acid (+ catalyst) = P2P

http://www.erowid.org/archive/rhodium/chemistry/p2p.phenylac...

6. In much the same way that benzoic acid + propionic acid = propiophenone (decarboxylation), to which reaction the following patent pertains:

http://www.freepatentsonline.com/4172097.html

This too is carried out in the gas phase, which appears to avoid the ‘tar’ accompanying the liquid-phase reactions.

(Not sure that I would want to scale this sucker up, 650 pounds / hour should be ample)

I am assuming of course that styrene oxide could be intentionally overoxidised, or isomerised, and that the product would in fact be phenylacetic acid. I am also assuming that P2P could be produced through the same gas phase reaction, containing the two carboxylic acids, that works for propiophenone.

If it works it would seem to be a perfectly legitimate exercise in recycling (right up until some irresponsible person mixed methylamine with it anyway). I am aware that this couldn’t possibly be the simple solution (albeit scary reactions) that it looks like, can someone tell me why?

tupence_hapeny - 4-4-2007 at 19:27

Here is an electrochemical synthesis of phenyl-2-propanone from this year, it uses benzyl bromide, acetic anhydride and platinum electrodes in an undivided cell, with 80+% yields.

http://www.rsc.org/publishing/journals/GC/article.asp?doi=b6...

Can someone please grab this article for me (I know this is a post re: styrene to P2P, however, it is still the same end product is it not).

Womble,

The limonene looks like the way to go, I cannot find anywhere where acetone alone will dissolve all the polymer, a mix of acetone and MEK will, but that's no good.

Can anyone draw up a procedure from start to finish - Styrene (+Limonene) = Styrene monomer + (NaOCl + NaBr (10:1)) = styrene oxide (NB TS-1 Zeolite or mordenite with Ti & HF = styrene to Phenylacetaldehyde in one step) - isomerization with SiO2 gel (gas phase) = phenylacetaldehyde + oxidation (HOW for quick & easy?) = phenylethanoic/acetic acid

tup

Sauron - 4-4-2007 at 19:47

I see. So all that blather about what to do about the drug war, and how much amateur science was threatened, etc etc was just so much eyewash because here you are cooking P2P.

Hypocrite!

Just another fucking meth cook.

The_Davster - 4-4-2007 at 19:52

Quote:

Originally posted by Sauron
I see. So all that blather about what to do about the drug war, and how much amateur science was threatened, etc etc was just so much eyewash because here you are cooking P2P.

Hypocrite!

Just another fucking meth cook.

Yeah I was just thinking this myself...
You are on some thin ice now with me, TH...

[Edited on 4-4-2007 by The_Davster]

Sauron - 4-4-2007 at 21:08

You know, we deal with a lot of dual-use (or multiuse) compounds on this forum. Acetic anhydride has a host of uses other than making heroin and anyway you can't make a damn bit ot that if you don't have morphine to acetylate. Same goes for acetyl chloride.

Same goes for benzaldehyde. Lots of other things too. There's room for doubt, and no reason to presume that someone is up to drug cookery. Piperidine for example has a bad rep because of PCP but it's also a very necessary deprotection reagent in Fmoc peptide chemistry.

However I have yet to hear of any great synthetic use for phenylacetone (P2P) other than making amphetamines. Oh, there may be some, but in a minor key and nothing than can't be worked around.

It has some industrial uses but nothing pertinent to amateur chemistry AFAIK. Just one famous illicit use.

madcease - 4-4-2007 at 21:41

Does anyone have any results regarding this???

not_important - 4-4-2007 at 23:35

The first patent given does not appear to deal with depolymerising polystyrene, but rather simply converting waste PS into clean, compact polystyrene.

Phenylacetic acid is useful in making pleasant smells. Its esters with shorter chain alcohols smell honey-like, often with overtones of rose. As the alcohol chain length increases the order shifts toward chocolate, sometimes with light floral hints of rose or orange, and then moves on into balsamic. The esters of phenethyl alcohol are rose-like for the short carboxylic acids, often with overtones of honey, move on into 'green' oders with floral hints, and becoming green-buttery with longer chains.

I once made both the acid and alcohol from polystyrene. Polystyrene foam can be compactified by heating it. This can be done in an oven, or with waste hot air from a kiln. The polystyrene con be converted to monomeric styrene by destructive distillation, best done under reduced pressure and/or blue to UV light. The distillation receiver should have a small amount of an antioxidant in it. The crude monomer is redistilled, again with antioxident in the receiver, to give a misture of styrene and ethylbenzene. This is converted to phenylacetic acid via the Willgerodt reaction or one of its kin; some of the ethylbenzene will react and a small amount won't. The acid will be in the form of the free acid mixed with the amide, or mostly as the thioamide for the modified Willgerodt reactions.

[Edited on 6-4-2007 by not_important]

tupence_hapeny - 6-4-2007 at 00:39

So, I can't work out a way to make shit?

MY pastime is now, in this country, illegal for the duration of the war on drugs and I am supposed to be utterly unconcerned with how long that takes?

If people want to make the stuff, I say let them, in fact, help them. Because quite frankly, they are at least (obviously not intentionally) demonstrating the stupidity of the current approach, by making their way to illicit substances using chemicals other than those denied me in order to prevent them achieving that purpose.

Quite simply, I personally do NOT care if they use up all the bloody styrene in this country, for once they would do me and others a service - making recycling work... The sooner it becomes blindingly fucking obvious that prohibiting amateur chemistry is not going to work, the better I'll like it. People making their own phenylacetic acid from styrene is a small start, and P2P from there, is a slightly bigger one, but IT IS a start

Sauron - 6-4-2007 at 01:51

All you are doing is wingeing about your criminality being, after all, criminal.

You are not an amateur chemist, you are a criminal and apparently proud of it.

So tell the judge you are proud of it when they incanrcerate your ass.

You do not speak for honest chemists.

You are a criminal.

Levi - 6-4-2007 at 02:13

Quote:

Originally posted by Sauron
All you are doing is wingeing about your criminality being, after all, criminal.

You are not an amateur chemist, you are a criminal and apparently proud of it.

So tell the judge you are proud of it when they incanrcerate your ass.

You do not speak for honest chemists.

You are a criminal.

According to the law, a large amount of the "honest chemists" on this board are criminals. Why should TH be worse than the rest? You call him a criminal because you believe he is doing something immoral whereas you feel that the "honest chemists" are being victimized. Nobody held a conference to determine who would be allowed into the honest chemist club. As far as I'm concerned, if he's posting intelligent information and is interested in the chemical theory behind the synthesis, then that makes him an honest chemist. It's the people with no concept of chemistry who just want an easy recipe for whatever drug they are addicted to that are the ones we should flame here. Additionally, while I don't think psychoactive drug making is the purest form of chemistry, it is chemistry (and a several notches above the k3wl b0mb makers if you ask me).

Sauron - 6-4-2007 at 02:42

Bullshit. He's out to turn this into a meth cook's kaffee klatch, swapping recipes for P2P. And all the time spouting garbage about the moral high tone he is upholding.

I call him a criminal not because what he advocates is immoral, but because what he advocates is blatantly and severely felonious in his own country and by his own statements.

There's a big difference between him and those of us who might be bending the rules here and there.

If he wants to come on here and talk chemistry, that's what this is for, but he was not talking chemistry was he?

He was talking advocacy of blatant criminality. Also a lot of claptrap about how drugs don't hurt anyone. Well, I've seen a lot of people hurt by drugs. Like by the meth cut with strychnine and weed killer (paraquat) in Thailand. The DEA didn't put it there, the fucking dealers did.

I've known people who died of cocaine heart.

So tell me again about how drugs are harmless.

And I'll call you a liar.

Nicodem - 6-4-2007 at 03:01

Quote:

Originally posted by Sauron
There's a big difference between him and those of us who might be bending the rules here and there.

It seems tasteless that the one accusing Tupence is the same one who started a thread like this. Or, should I say: "Let the one who is without sin throw the first stone."

Though I do not like Tupence, mainly because he sounds like Synthetikal on medication and with a spell checker and find his apologetical ideology disgusting, I still do not consider someone discussing how to make illegal drugs a criminal. His attitude certainly is hypocritical, but what is discussing about making illegal drugs in comparison with discussing about making weapons of mass destruction? Comparing a wanabe mass murderer with a wannabe meth cook is like comparing Saddam or Bush with your local meth cook or heroin diller. So where is that "big difference" you talk about?

Levi - 6-4-2007 at 03:05

Unless someone is being forced to do drugs, whatever the outcome, the responsibility rests with the individual. If they die from it that is their responsibility. If they go blind, become incontinent, stop sleeping, ruin relationships and/or are unable to become sexually aroused, the blame rests completely with the individual. Drugs do, indeed, cause harm... as do cars, hammers, airplanes, bacteria, pollution and broken condoms.
I do not want to see this forum become a hangout for stoners any more than you do but I think your statements attacked him before he actually said anything highly inappropriate. I must admit, though, I missed his request for a "quick & easy" procedure "from start to finish" on my first read. The rest of his comments, though, about whether or not a certain solvent would work better than another was within the realm of legitimate chemistry, and I'm interested in whether or not such a procedure actually exists. The way I see it, if a synthesis for whatever drug is discovered which is simple and performed entirely with common OTC items, it will become impossible to stop and therefore there need be no more need to ban useful chemicals.

tupence_hapeny - 6-4-2007 at 04:14

Ummm,

Is it possible to get this entire conversation, re: legal, social, moral and ethical out of this board please?

Levi,

You are on the money, I don't see it as likely that ANY government will ban styrene (more IS the pity). Point being, if it possible to establish that the substances that the government wishes to fight anyone making - by banning legitimate amateur chemistry (which like it or lump it, they have done here) - cannot be succesful because the same substance can be made from chemicals which are everywhere - I may be able to legally indulge in amateur chemistry again.

Sauron,

If people choose to take drugs, they choose the consequences of having done so - it's the old story - the devil said to man, 'take everything you want - then pay for it', I don't see why other peoples choices should be paid for by me, however (and be that as it might) that is the situation here and will be for the foreseeable future. In my opinion, if it can be shown that drugs can be manufactured via chemicals that no government is CAPABLE of banning (whether because of logistical, financial or industrial pressure) then sooner or later they will face a choice. The sooner they face that choice the better (ie. I can have my glassware again).

As to being a criminal, I rather believe that PROOF is required of an 'actual' offence, for which you need EVIDENCE. As far as I am aware, what I may or may not personally believe is not a criminal offence (caveat, unless I support terrorism), nor is a theoretical discussion of basic chemistry. As to whether drugs are harmful, of course they fucking are - they ARE poisons and if you wish to take them for any length of time you need your head read. What I fail to understand is how they are any more harmful than alcohol or tobacco (given that they are less harmful by several orders of magnitude). That being so, why shouldn't they be available in much the same way as both alcohol and tobacco - and why should such volumes of people be imprisoned for their choice of drug?

Nicodem,

I appreciate your attitude to this aspect of our discussions, and reiterate, I have no intention of making ANYTHING illegal. That said, I regard (as stated before) the war on drugs, from a slightly different perspective (ie. a legal one), although I personally (despite some personal experience, which was long ago & which I survived) believe that drugs aren't good for you - this approach isn't going to fix the problem. The drugs aren't going away and society is just going to have to adjust.

PS Why thank you, although I rather dislike the reference to Synthetikal, you did say that I sounded saner than they and with a better spell checking facility (I don't use one).

As to everyone else, the War on drugs isn't going away - it serves way too many people, providing votes to politicians, jobs to police, lawyers and judges, sales & ratings to the media. It also provides massive profits to people with no ethics and causes massive social problems. Unfortunately, noone wants the thing to end, it is just so bountiful - despite destroying lives, jobs, etc. Whatever efforts are devoted to fighting it will be wasted as the politicians will never say we need less laws and/or less police or whatever.

So where does that leave amateur chemistry here? In one word, fucked - if one chooses to own glassware at all in this place one is presumptively a criminal, while virtually all accessible reagents and solvents are banned and a criminal offence to own or order. This is not going to change unless the list of prohibited items becomes unworkable and unenforceable, which will be immediately the government attempts to prohibit either styrene or acetic acid. As these cannot be prohibited and would quickly become the most often utilised reagents for meth cooks - of what use is the remainder of the list in preventing the production of drugs? Therefore, of what utility is the list at all?

So, once the list is of no relevance to whether or not the person is producing drugs, how then could police validly presume (as per the legislation) that the owner of listed substances was producing drugs, because they owned something on the list? The answer is that they could not and due to the illogical nature of the presumption it would be invalid - thus invalidating both the list and the presumption. Wham, I can own glassware and do stuff again.

Not-important,

Finally back to the chemistry.... (Nicodem will be happy),

Ummm, yeah - thought that looked easy, the first patent does not depolymerize the polystyrene, it merely dissolves it. I did a quick patent search and here is a recent patent regarding the depolymerization of styrene by heating the same to ~300C with an inert atmosphere (CO2) to prepare 99.5% pure monomer:

http://www.freepatentsonline.com/6018085.html

Here is an older patent which shows that by first melting the polystyrene no solvent is needed (I don't know if this is accessible)

http://www.freepatentsonline.com/3901951.pdf

(I have attached this patent in PDF)

Their yield (without inert atmosphere) was up to 59% of starting polystyrene to styrene monomer.

I believe the original post referred to a gas phase process for the oxidation of styrene to styrene oxide (epoxide) and another gas phase reaction of styrene oxide to phenylacetaldehyde (with silica gel - if not I have this from elsewhere).

If this is the intended use, I cannot see how the initial reaction could benefit from an inert atmosphere, as the oxidation of the styrene would be a plus would it not?

tup

[Edited on 7-4-2007 by tupence_hapeny]

Attachment: Depolymerisation of Styrene (US Patent 3901951).pdf (160kB)
This file has been downloaded 1373 times

on the other hand .. re p2p

chemrox - 6-4-2007 at 07:24

On the other hand:

Years ago I participated in an amphetamine synthesis contest and the whole point was to show that no matter what material you made unavailable there were workarounds and ways to make methA. I suppose the same thing applies to p2p and showing that p2p can be made from so many different starting points that making it illegal is absurd. There is something deeply wrong with US society and the speed epidemic is just a symptom. Furthermore prohibition never worked. The DW is just another example. I say more power to those who publish methA syns and show it can be made from just about anything. I don't understand the appeal myself.. but forcing manufacture into the hands of the cynical, desperate and unskilled is just making it that more harmful to the people who are going to get it one way or another.

p2p was a cheap route to methA until it was proscribed. The ephedrine route was always known and available but with controls over p2p and one by one the materials IT can be made from .. ad nauseum .. ephedrine ended up being te cheaper starting material bringing iodine and phospohorous under scrutiny and finally making ephedrine virtually illegal. Now this really pisses me off .. I'm a diver and ephedrine is the agent of choice to quickly clear sinuses for a period of three to six hours. So an easy way to make p2p is, in my view, a service to sportsmen and pilots as well as a blow to the DW. All good things.

[Edited on 6-4-2007 by chemrox]

[Edited on 6-4-2007 by chemrox]

roamingnome - 6-4-2007 at 09:18

Method for recovering styrene monomer from polystyrene resin by using a catalyst
United States Patent 6380448
http://www.freepatentsonline.com/6380448.html

hydrated Epsom Salts are claimed to work

long ago ive come to the conclusion that opinions are meant for the fire

tupence_hapeny - 6-4-2007 at 11:35

Here is the patent for the production of phenylacetaldehyde from styrene oxide (epoxy), it uses the passage of gas phase styrene oxide through silica gel (sorta explains the problem with isolating the yield experienced by so many researchers & also why the 'reactions' caused hydrolysis of the product from the epoxidation):

http://www.freepatentsonline.com/4650908.html

As there is also a gas-phase oxidation of styrene, could this not all be run in one line?

depolymerization =(+ Heat & MgSO4)=> styrene =(Heat + supported silver catalyst)=> Styrene oxide =(silica gel)=> Phenylacetaldehyde

Here is the references regarding the vapor phase oxidation of styrene (the yields are ~50-75%, the remainder is unchanged styrene apparently):

http://www.freepatentsonline.com/5145968.html

http://www.freepatentsonline.com/4894467.html

[Edited on 7-4-2007 by tupence_hapeny]

Attachment: Production of Arylacetaldehydes (US Patent 4650908-1).pdf (125kB)
This file has been downloaded 1381 times

jim20/20 - 6-4-2007 at 12:07

Quote:

I still do not consider someone discussing how to make illegal drugs a criminal. His attitude certainly is hypocritical, but what is discussing about making illegal drugs in comparison with discussing about making weapons of mass destruction?

of course you are right nic
but neither is amateur chemistry

nor is political philosphy for that matter

'thou shalt oppose nor embarass those in power without being punished'

the hive is gone and the official line seems dubious

not_important - 6-4-2007 at 13:49

Quote:

Originally posted by tupence_hapeny...

As there is also a gas-phase oxidation of styrene, could this not all be run in one line?

depolymerization =(+ Heat & MgSO4)=> styrene =(Heat + supported silver catalyst)=> Styrene oxide =(silica gel)=> Phenylacetaldehyde
...

OK, here's some experience talking

First off, patents tend to omit minor details that would make it simple to replicate the process being described. Sometimes a patent is filed not because the process was practical at the time, but as a protection in case someone else came up with a variant that could be economically useful. So don't expect every patent to end up being useful to you.

The depolymerisation doesn't need a catalyst, try it plain and with a catalyst and compare the yields. The depolymerisation is aided by somewhat reduced pressure, and by blue-to-UV light.

I've read lab reports that found that the presence of oxygen lead to the reforming of styrene polymers, properly oligomers which are formed even in inert atmosphere but to a lesser extent - dealing with free radical processes here.

Because of the oligomers, as well as other decomposition products, it is worth fractionating the styrene. A Vigreux column was OK.

The conversion to the epoxide is a little tricky. BTW - not all the olefin is either unconverted or changed to epoxide, some ends up further oxidised including being fully oxidised to CO2 and H2O. Too much air/oxygen can give an interesting blow torch effect inside the catalyst tube; it is rather a bother to have a nice piece of heavy wall pyrex process tubing start to glow brightly and sag down, more so when this results in the tube's failure and the flaming gases come rushing out. Do not try this in your kitchen or bathroom, don't try it in any room where soot covered walls are not acceptable.

You need to get the proper amounts of oxygen to styrene, and the proper contact times for the temperature you are running at. Pressures a greater than atmospheric and usually helpful, the patents even mention that.

Matching the rate of styrene production via destructive distillation to the need for tightly controlled O2/styrene rations and contact times (flow rates) in forming the epoxide is not a simple chore. It's much easier to make the styrene, and use a vaporiser/mixer to get the right ratios and flow rates. The problem is increased by the opposing pressure ranges favored by each process.

The epoxidation and and rearrangement are a closer match, but still perhaps not close enough. Experimentation will tell.

I went the epoxide route because I wanted b-phenylethanol too. It took more than a bit of tinkering to get it working. It still was more trouble than using cold dilute permanganate to form the diol, and rearranging that with an acid catalyst.

As for going to the acid, Willgerodt using heavy walled pipe as an autoclave with an internal glass reaction vessel is a lot less work than going through the aldehyde.

Of course I only wanted a couple of hundred grams of the acid, if you were going into manufacturing the air oxidation route would likely be better. But why stop with the aldehyde? With some research you might be able to further oxidise the aldehyde, inject AcOH, and produce your desired product in one vapour phase production stream. I'm sure that there are various ... notable figures who might be interested in financing such a research project. However that might prove to be a little too interesting of a career choice.

While you're at it, do a search on the phrase "micro reactor" for a way that eases the path from research to macro quantities.

Sauron - 6-4-2007 at 20:47

@Nicodem, I have NEVER advocating making weapons of mass destruction on or off this board. To say I have done so is FALSE. I have discoursed on them, and particularly on some of their precursors. So have many others. But I have also advised anyone who seemed in the slightest inclined to actually try preparing them to abandon such plans.

@th on the other hand is an advocate of making illegal drugs, and is proposing that all of us do likewise as a supposed path to less restrictions on our hobby. THAT absurdity is where I became disgusted with him and his rhetoric and not his (rather puerile) discussion of how to make P2P from PS refuse.

I am not the only member to call bullshit on this guy, I see at least one moderator doing so although it is unclear whether or not he was acting in his official capacity or privately.

I think any reasonably person would conclude from @th's remarks in this thread and one other, that he is as I concluded, a drug cook. I do not go around the forum railing at anyone I think is a drug cook; but @th went far beynd the norm and cloaked his criminality in supposedly the holy cause of defending Amateur Chemistry, which is just, IMO, a pose to hide his real intent just as pretending that utilizing polystyrene to make phenylacetone is a pose. Else he might propose making polystyrene into something else, that is valuable and desirable and non-drug related, all in the name of the Ozzie environment. But no, he settles on P2P.

P2P is a Sch 1 (I think) controlled substance now in USA. It is treated just as if it were heroin. It is not merely a listed precursor.

If we are in doubt as to @TH's status we can just ask him: are you making drugs or are you not?

If he answers honestly then at least he will have displayed some cojones.

If he says it is none of our business then we are eleft to draw our own conclusions.

I have already stated my own position relative to WMD's. I study them on PAPER. If someone wants to study illicit drugs on PAPER I do not care. If someone makes them where they are legal I do not care (or at least I will keep my disapproval to myself.)

But, I say again, drug cooks and dealers are the roopt cause of our problems in amateur chemistry and a lot of larger problems in the world. Let's put the blame where the blame belongs. It's long past time to abandon the armchair libertarianism and laissez-faire bullshit and realize that we are all being made to suffer for the wrongdoings of a tiny minority of avaricious, greedy, arrogant criminals. We should not have ever tolerated them in our midst and we should not do so now.

Nicodem - 6-4-2007 at 22:48

Quote:

Originally posted by tupence_hapeny
depolymerization =(+ Heat & MgSO4)=> styrene =(Heat + supported silver catalyst)=> Styrene oxide =(silica gel)=> Phenylacetaldehyde

Letting industrial proceses aside, you might consider not to complicate things were not necessary:

1.) Styrene is a so called OTC compound. You can buy it pure of technical quality in specialized stores or reagent grade from a chemical supplier. Both are extremely cheap. I see no point for something like a tedious distillation by destructive depolymerization that might end in explosions if there is an air leak in the system.

2.) Styrene epoxidation is as simple a reaction as it can get. I have done it for fun in the times I was a bored amateur without any special equipment (though you do need a distillation set and an aspirator). You can use completely OTC reagents, like trichloroisocyanuric acid or Oxone, both available in their pure form in any larger store.

3.) The styrene oxide rearrangement can be performed in liquid phase, no need for tube furnaces and stuff like that. But if you just have to use a gas phase reaction try to read this instead: Tetrahedron Letters, 29 (1988) 1471-1472.

4.) The epoxidation of styrene, the rearrangement, and oxidation to phenylacetic acid can be performed in a one-pot method using formic acid, aq. H2O2 and H2SO4. I tried this once and had a yield of 7% (actually, I did not even bother characterizing it, but it was a carboxylic acid and had the same typical smell as reagent grade PhCH2COOH). I know what should be optimized for a better yield, but since I have no use for phenylacetic acid (and if I had any use I would not need to prepare it) I never tried to do any better than that. The aldehyde to carboxylic acid oxidation reaction is described in Synthesis, (1993) 295-297 while the first two reaction steps are trivial and there is no particular limitation for a one-pot process.

5.) Like not_important said, the Willgerodt reaction followed by hydrolysis is way more rational than your multistep proposal unless you have some industry to do the work for you. Besides all this styrene stuff was already discussed add nauseam in other threads, the most useful for you would be this one. But do UTFSE by yourself!

tupence_hapeny - 7-4-2007 at 02:47

Nicodem,

I have intentionally gone a different way to the Wilgerodt-Kindler reaction, simply because I have a marked aversion to playing with hydrogen sulfide (H2S) and do not believe that this reaction is SAFE in the hands of either an
amateur chemist or a ‘meth’ cook (which I note that I am still being called). Quite simply, the capacity for this gas to be released in some quantity is dangerous not only to the person using the reaction, but also to persons in the immediate area of
the same. Another factor is the emissions, which is the primary reason why industry does not use this.

Yes, styrene monomer is widely available – albeit in an impure form – although I would suggest that the same is easily banned (or made available only under license), whereas polystyrene cannot be banned effectively.

Finally, I have noticed numerous threads on this topic, the conversion of the polymer to the monomer, then to the aldehyde, etc. For the most part such threads are silent on detail and specifics, I believe that it is time to ‘put up or shut up’ if you will, and examine the specific reactions and the mechanics of the conversions in order to ascertain whether this is, or is not, a viable source of the desired compound(s). Perhaps even exploding some popular myths on the way.

Not_important,

As stated above, I am trying to dodge the Wilgerodt-Kindler style reaction, due to the level of byproducts which must be dealt with (although, and as a recurring theme, could NMP [as a high-boiling amine] be used instead of pyridine or morpholine?). I am interested in your experiences with this specific type of reaction, although I am interested to know the role of the ‘blue-light’ in the sequence (as no mention is made in any of the patents of such)?
As to the reactions, the epoxidation requires oxygen and an inert gas, would carbon dioxide suffice (as this would already be in the mix and moreover is given off by the reactions). That would mean that oxygen could be added at a predetermined rate (based on the flow from the styrene depolymerization reactor) along with some steam in the final step.

Alternatively, bearing in mind that the object is to provide a workable synthesis, could a minor amount of oxygen be added to the carbon dioxide during the styrene depolymerisation? This would cut down on unwanted side-reactions, while providing the oxygen for the next step – thus needing only additional heat in order to complete the epoxidation step.

Back to the chemistry,

The phenylacetaldehyde coming from the reaction tube is of course going to be accompanied by unreacted styrene, three xylenes, and assorted dimers and trimers (and tetramers), although (and providing the reactions work as advertised) these should be mainly styrene. I am unaware if either styrene or xylene would react with acetic acid/acetone, if they will it will be necessary to remove them, if not, do it at the end. Personally I would prefer purification at this stage.

Making the Ketone
There are three major routes:

(1) reaction between phenylacetic acid and acetic acid;
http://www.orgsyn.org/orgsyn/prep.asp?prep=cv2p0389

(2) reaction between phenylacetic acid and acetone; &

http://www.freepatentsonline.com/4528400.html
http://www.freepatentsonline.com/4570021.html

(NB these patents actually claims to be useful in making BMK)

(3) reaction between phenylacetaldehyde and acetic acid

http://www.freepatentsonline.com/6495696.html
http://www.freepatentsonline.com/6392099.html

Given that phenylacetaldehyde reacts with acetic acid to give the desired ketone (the patent is for cyclopropylketone) and phenylacetic acid reacts with acetone to give the desired ketone, wouldn’t a fourth variant be at least theoretically possible? Being the reaction between phenylacetaldehyde and acetone? (If not, I have patents for the production of acetic acid from ethanol in the gas phase).

However, if the phenylacetaldehyde cannot be used directly, I am yet to find a mechanism for the conversion of the same to the acid – except in the liquid phase reaction with nickel peroxide (nickel oxide hydroxide [thanks Sauron]).

Sauron,

Sir, I note your continued strident remarks and wish to state unambiguously and categorically, that I do NOT NEED to make drugs and reiterate my statement that I have no intention of doing so. That being said, the development of industrial routes to compounds that are listed, using none of the compounds that are listed – purely to prevent the making of the first – is a matter of serious, professional interest.

The synthetic route under discussion is, of design, an industrial style process – knowledge of the mechanics of which may be extremely useful to myself (and potentially my client) in some, as yet to arise, situation or occasion. It will however be necessary to establish that such a route is within the limited knowledge of chemistry that is presumed to be within the grasp of the average, or slightly above average, ‘cook’, thus the emphasis upon simplicity and ease of operation. Additionally, if actual ‘criminals’ use this information to make drugs and get busted, their actions will only advance my argument, given that the information from their trial will be admissible in other trials to demonstrate the validity of the route.

Cold blooded enough for you Sir?

tup

[Edited on 7-4-2007 by tupence_hapeny]

Sandmeyer - 7-4-2007 at 03:24

Quote:

Originally posted by Nicodem

Though I do not like Tupence, mainly because he sounds like Synthetikal on medication and with a spell checker and find his apologetical ideology disgusting

I think all of them, including "Sauron" (our "retired defense consultant") sound more or less the same, maybe all these personalities co-exist in the same body. It must be the madness part of sciencemadness that attract all those crazies..

[Edited on 7-4-2007 by Sandmeyer]

Sauron - 7-4-2007 at 03:51

@sandmeyer's comment is sufficiently asinine to require no additional comment from me. Did he actually mean ti suggest that I am @th?

What an insult!

And no need for quote marks about retired defense consultant, @sandmeyer, I AM a retired defense consultant. And a senior defense-intelligence journalist as a result. It so happens that on the MadHatter ftp site there is a book with an entire chapter devoted to me and my work and my photos grace the cover of that book and the chapter. So, take your little puerile sneer and go fuck yourself with it.

(You see, gentlemen and ladies, I have been the victim of @Sandmeyer's poison pen before and I am not about to accept any more abuse from him.)

[Edited on 7-4-2007 by Sauron]

tupence_hapeny - 7-4-2007 at 06:58

I can't think why...

solo - 7-4-2007 at 07:19

Off topic- Observation

The forum reminds me of a large table setting with many types of food....one takes the one to be enjoyed and the rest are for others which seek the same joy with other foods from the same table......, hence take that which you like and leave the rest alone as it's not in your plate to either comment or criticise........solo

[Edited on 7-4-2007 by solo]

not_important - 7-4-2007 at 07:31

Quote:

Originally posted by tupence_hapeny
styrene monomer is widely available – albeit in an impure form

Just anti-oxidants in small amount, distillation takes care of them

Quote:

although I am interested to know the role of the ‘blue-light’ in the sequence (as no mention is made in any of the patents of such)?

Unfiltered mercury arc is best, but harder for amateur to come by. Pumps more energy into the PS, aiding in bond breaking

Quote:

As to the reactions, the epoxidation requires oxygen and an inert gas, would carbon dioxide suffice (as this would already be in the mix and moreover is given off by the reactions). That would mean that oxygen could be added at a predetermined rate (based on the flow from the styrene depolymerization reactor) along with some steam in the final step.

Except on a fairly large scale the flow is not smooth and predictable

Quote:

Alternatively, bearing in mind that the object is to provide a workable synthesis, could a minor amount of oxygen be added to the carbon dioxide during the styrene depolymerisation? This would cut down on unwanted side-reactions, while providing the oxygen for the next step – thus needing only additional heat in order to complete the epoxidation step.

How does O2 cut down on unwanted side-reactions in the depolymerisation? Adding a di-radical to a free raadical process you are.

Quote:

The phenylacetaldehyde coming from the reaction tube is of course going to be accompanied by unreacted styrene, three xylenes, and assorted dimers and trimers (and tetramers), although (and providing the reactions work as advertised) these should be mainly styrene.

The depoly step gives styrene, ethylbenzene, toluene, styrene oligomers, and traces of xylenes. The oligomers have a reactive double bond and will react in the oxidation stage, as well as condense out if it's cool enough, and react with each other and the styrene to slowly plastic/gorp coat everything.

Quote:

(2) reaction between phenylacetic acid and acetone;
(NB these patents actually claims to be useful in making BMK)

That's right, BMK, standard lab method, not your target.

Quote:

(3) reaction between phenylacetaldehyde and acetic acid

Check the term Perkin's reaction, which is the common type for aldehyde + acid. The high reactivity of the benzl hydrogens may be enough to run the way the patents say, I have doubts on that. It's a post Reagan era US patent, many of which are the equivalent of vapourware. Try it and see.

Quote:

Given that phenylacetaldehyde reacts with acetic acid to give the desired ketone (the patent is for cyclopropylketone) and phenylacetic acid reacts with acetone to give the desired ketone, wouldn’t a fourth variant be at least theoretically possible? Being the reaction between phenylacetaldehyde and acetone?

PhCH2CHO + CH3COCH3 => PhCH2CH=CHCOCH3

And I'm too sleepy to type more.

Nicodem - 7-4-2007 at 09:58

Quote:

Originally posted by tupence_hapeny
Finally, I have noticed numerous threads on this topic, the conversion of the polymer to the monomer, then to the aldehyde, etc. For the most part such threads are silent on detail and specifics

Why would someone bother depolymerizing polystyrene when he could just buy the damn thing for so little money? It might have been mentioned several times, but only as a possibility or curiosity since polystyrene is a rare case where depolymerisation is actually possible. You can't expect anybody trying out such a procedure just for the fun of it. You seem to find it more interesting than anybody up to now, so you try it out.

Quote:

As stated above, I am trying to dodge the Wilgerodt-Kindler style reaction, due to the level of byproducts which must be dealt with (although, and as a recurring theme, could NMP [as a high-boiling amine] be used instead of pyridine or morpholine?).

I wander why I even try explaining you anything when it is so damn obvious you do not read the replies to your post unless they contain some ideological discourse. NMP is not an amine, it is an amide, something completely different and I already explained you in your other thread that it is not a base! Obviously pyridine can not be used in the Willgerodt reaction as it is neither a primary or secondary amine nor ammonia, so like usually you confused stuff. And again you demonstrate you read nothing of what is provided to you or you would have known that, by the Chinese patent in the linked thread, practically no H2S is evolved unless in the hands of a fool.

Quote:

As to the reactions, the epoxidation requires oxygen and an inert gas, would carbon dioxide suffice (as this would already be in the mix and moreover is given off by the reactions).

Dry air is a mixture of O2 and an inert gas. Anyway, why would CO2 be amongst the reaction products?

roamingnome - 7-4-2007 at 10:14

yes surf board shapers should and can buy pure monomer, its cheap , but

in mad max beyond thunderdome 2045 when the dude in the leather flight helmet finds a styrofoam cup he smiles knowing that each benzene ring will help him fight off the evil oil bikers.....

tupence_hapeny - 7-4-2007 at 10:16

Not_important,

I address your points, however, I will attempt to do so in a logical order.

(1) The pyrolysis of styrene (as is the case according to the attached article, with most polymers) can be carried out in a controlled manner by controlling the temperature of the reaction vessel. In fact, the basic assumption of the author is that by conducting the degradation at the lowest temperature at which it occurs, it is possible to keep the degradation to around 1%/min. This should be able to be worked upon in order to allow such pyrolysis to take place at a steady, predetermined rate (I think the lowest temperature would be around 300C – perhaps less with a partial vacuum).

Alternatively, it may be possible to melt the styrene in an adjacent vessel, then deliver it to the reactor in a molten form (I suggest at or around 250C) at a predetermined rate. With vacuum it should not be necessary to heat it much further in order to commence depolymerisation, and as the rate appears to be somewhat temperature dependent, it should be possible to establish some sort of constant rate (perhaps temperature * X = monomer / minute or somesuch function, although I doubt it will be so simple).

Granted this stage of the reaction is purely speculative at present, however, this could be quite manageable. I would also suggest that instead of merely purging the vessel and operating under a static blanket of carbon dioxide, a flow (in the appropriate ratio, as required by the epoxidation step) could be delivered, with the additional benefit of drawing the liberated gaseous styrene monomer into the next stage of the reactor

(2) I appreciate the fact that many patents are rather more speculative than they appear, however, they should normally work to some extent. By the way, the reaction between phenylacetic acid and acetone is claimed to result in Phenyl-2-propanone (NOT BMK, my mistake), with the acetone being regarded as a precursor to acetic acid.

(3) I merely suggested the use of some oxygen (around 5% as opposed to pure air) as a compromise between pure air and carbon dioxide in the first step. Even I am aware that oxygen will not prevent oxidation, however, surely the 95% carbon dioxide will prevent some of the oxidation experienced in pure air. The 5% oxygen could then be used in the epoxidation step. I personally would prefer that a predetermined amount of oxygen (based upon the rate of depolymerisation and in the proper ratio vis-à-vis the epoxidation step, was delivered directly prior to the epoxidation step.

(4) As to the condensation of the miscellaneous polymeric by-products, I would suggest that a trap is incorporated just after the product of the depolymerisation step leaves the reactor. The product gas mixture should be allowed to cool to just above the boiling point of styrene (~100C I believe), and by this mechanism the high-boiling compounds would not make it into the epoxidation step, having condensed and been collected in the trap.

(5) The by-products remaining would be essentially the xylene, toluene and ethylbenzene (according to numerous papers, ethylbenzene is predominant at some temperatures). These would presumably be oxidized during the epoxidation step (although I am unaware if they would form their respective acids or aldehydes). The major remaining ingredient of this product would be the unreacted styrene, which could of course be recycled as a solvent for the styrene prior the melting of the mix.

(6) I have not yet put a great deal of though into the separation step, however, this presumably would be possible, although fractional distillation will be necessary.

Nicodem,

I have no response the first parts of the first parts (however, I am almost certain I have read someone claiming to have had success with pyridine (here or elsewhere), obviously they did not).

So, the invitation from yourself to the person suggesting using the information in that patent, to feel free to poison themselves with the H2S was a lie?

As to the last, CO2 is given off by over-oxidation in the epoxidation step. In fact, in the patent one of the x-methyl-styrenes gave essentially a quantitive yield of the stuff

Roamingnome,

Thanks for that, I used to work with glass and I know the smell (and the bloody itch as well), however, all I had been able to find in normal glass resins was 30-60% with polyester. I hadn't thought to search the specialist surfboard shops, they have got it. My thought process for this thread was that if it were necessary for people to distill from a shitload of polyester - they might as well work in the gas phase - not valid.

[Edited on 8-4-2007 by tupence_hapeny]

Attachment: Luderwald, Ingo 'Mass Spectroscopy of Synthetic Polymers' (1982) 54(2) Pure & Applied Chem 255 (IUPAC).pdf (594kB)
This file has been downloaded 1271 times

tupence_hapeny - 7-4-2007 at 11:32

Sorry (re. double post) but as it is possible to purchase pure styrene monomer (again, my bad) the easiest method of getting to the phenylacetaldehyde would be to epoxidise the styrene (such as the non-metal, hypochlorite option):

http://www.erowid.org/archive/rhodium/chemistry/epoxidation....

Distilling off the product, and passing the styrene oxide through silica gel (packed column style) a small amount of steam would be a good thing, as would CO2.

The purified phenylacetaldehyde could then be oxidised further with Nickel Oxide Hydroxide which is (according to the article cited on this site) a great agent for the oxidation of aldehydes to acids. It is used as a catalyst with hypochlorite.

Then choose whatever method you wish to get to the ketone.

[Edited on 8-4-2007 by tupence_hapeny]

Attachment: Non-metal.alkene.epoxidation (Styrene Oxide).pdf (63kB)
This file has been downloaded 1614 times

chemsitry for the sake of chemsitry

roamingnome - 7-4-2007 at 12:50

since your on a 3 point shooting spree with this topic and the full paper on hypochlorite in butanol with Br seems appealing.
for your stated purposes it seems you should reach for the half-court shot with that epoxide substrate

for example
Abstract
The direction of the oxirane ring opening in the polymerization of styrene oxide by sodium methoxide was determined on the basis of the structure of the products obtained. The oxirane ring opening was found to occur almost exclusively in -beta position. This result was compared with a model reaction, i.e. the methanol addition to styrene oxide in the presence of sodium methoxide. In the model reaction the oxirane ring opening occurred to ca. 35% in -position and to ca. 65% in beta-position.
The anionic polymerization of styrene oxide. Polymer structure and direction of ring opening
Die Makromolekulare Chemie
Volume 183, Issue 3 , Pages 587 - 591

i dont know what this means exactly and this paper probably bounces of the rim, but if you stumble across the "perfect reaction" be sure to post it....

i looked into methyl radical addition. Not trying to sound sissy when i see all these sticky nasty steps happening, but ultimitaly the "elegant" protocol is still yet to be unearthed. i.e if you dont need the PAA for purfume then this aldehyde creating and then making the acid form then ketene lamping your self to p2p seems like an epic....

http://www.mdpi.net/ecsoc/ecsoc-/Papers/e0038/e0038.htm
pesky side reactions

[Edited on 7-4-2007 by roamingnome]

tupence_hapeny - 7-4-2007 at 15:25

For those that think the science in this thread is lacking in something, perhaps this will alleviate your concerns somewhat:

http://www.niscair.res.in/ScienceCommunication/ResearchJourn...

So what you say, it is hardly likely that most of the people on this board, let alone a lowly drug-cook could make tetraphenylporphyrins? Well, I would normally agree, however, I found this:

Gas-phase synthesis of 5,10,15,20-tetraphenylporphyrin:

http://greenchem.uoregon.edu/Pages/Overview.php?WhereFrom=Re...

MW Synthesis of 5,10,15,20-tetraphenylporphyrin:

http://greenchem.uoregon.edu/Pages/Overview.php?WhereFrom=Re...

Metallation of 5,10,15,20-tetraphenylporphyrin:

http://greenchem.uoregon.edu/Pages/Overview.php?WhereFrom=Re...

All we need now is for one of the 'actual' chemists on this board to say whether or not the procedure for metallating the porphyrin with zinc is valid for metallating said porphyrin with Manganese. We would also of course require some details as to whether the 'acetate' of the porphyrin complex can be formed directly or whether an involved procedure is necessary.

NB The 'lab procedures' link on the results pages gives a PDF copy of the actual lab procedure to make the porphyrin, which is for undergraduate students, and not all that hard to follow.

tup

Nicodem - 8-4-2007 at 03:17

Quote:

Originally posted by tupence_hapeny
Nicodem,

I have no response the first parts of the first parts (however, I am almost certain I have read someone claiming to have had success with pyridine (here or elsewhere), obviously they did not).

Well, now that I'm more familiar with how your confused mind works I can claim that you confused pyridine with piperidine.
Am I right?

Quote:

So, the invitation from yourself to the person suggesting using the information in that patent, to feel free to poison themselves with the H2S was a lie?

Fools are always in danger of poisoning themselves when playing with chemicals, that's why the warning. Does a cook know what the hell is he doing? Does he know he must not acidify the polysulfide solution? No he does not - that's why the warning.

tupence_hapeny - 8-4-2007 at 04:15

Quote:

Originally posted by Nicodem

Quote:

Well, now that I'm more familiar with how your confused mind works I can claim that you confused pyridine with piperidine.
Am I right?

Quote:

So, the invitation from yourself to the person suggesting using the information in that patent, to feel free to poison themselves with the H2S was a lie?

Nicodem,

mmmmmm, you may be right in regard to the first part........

As to the second, I don't believe that it is possible to download the relevant patent's translation from that topic.

Next, what no comment on the porphyrins?

Maybe I should find a topic where they may be discussed?

not_important - 8-4-2007 at 06:33

Quote:

Originally posted by tupence_hapeny
...
Next, what no comment on the porphyrins?

Maybe I should find a topic where they may be discussed?

Topic drift, while not a mortal sin, can be a venial one.

tupence_hapeny - 8-4-2007 at 06:39

not_important,

Yet how is it topic drift, considering that TPP is the only agent yet discovered that can transform styrene to its oxide in 100% yields? I find a step-by-step synthesis of TMP that is so easy even k3wls could do it & you call that topic drift?

All I need now is a synthetic route for iodosylbenzene...

tup

Nicodem - 8-4-2007 at 07:34

Your tendency to complicate and confuse is admirable, but yet of little practical value.
There are hundreds of methods for the preparation of styrene oxide published and most are more practical than any you proposed up to now. Why would anybody use some weird unpractical method when the same thing can be performed by a simple method using either TCCA, Oxone, H2O2, sodium perborate, sodium percarbonate or even common bleach, all chemicals that can be obtained simply by going shopping to the nearest consumerism worshiping temple. I thought you were after a simple, fully OTC method? Do you really expect any of us seriously discussing about methods that have no use beside the academic interest or potential industrial application? Get grounded to the earth and perhaps there can be found a topic worth discussion. This is a forum for amateur science.

tupence_hapeny - 8-4-2007 at 07:39

Look, I find it extremely exciting that amateur chemists can now synthesize such advanced structures, the use of which is yet to be fully explored by the scientific community. I admit porphyrins have little utility in this OTC type thread, however, I still believe that they are of some interest.

That being said, and the fact that the hypochlorite/bromine epoxidation with the silica isomerisation followed by nickel peroxide to the acid, basically provides a viable OTC route to phenylacetic acid - I have started a thread on the porphyrins and will now leave this thread to whomever finds it of utility.

Is that okay with you?

tup

rannyfash - 13-7-2012 at 17:12

i hope you dont mind me dropping this here, it is somewhat unrelated to a small minority however you could repeat the kornblum oxidation to obtain p2p instead of the last step using NH3 resulting in the censored product

2-bromopropyl benzene from recycled polystyrene.png - 12kB

[Edited on 14-7-2012 by rannyfash]

solo - 14-7-2012 at 13:44

Reference Information

Electrosynthesis of phenyl-2-propanone derivatives from benzyl bromides and acetic anhydride in an unsupported micro-flow cell electrolysis process
Ping He , Paul Watts , Frank Marken and Stephen J. Haswell
Green Chem.
2007,9, 20-22
DOI: 10.1039/B610415K

Attachment: Electrosynthesis of phenyl-2-propanone derivatives from benzyl bromides and acetic anhydride in an unsupported micro-flo (243kB)
This file has been downloaded 2266 times

polymerizer87 - 17-7-2012 at 16:30

Quote: Originally posted by rannyfash

i hope you dont mind me dropping this here, it is somewhat unrelated to a small minority however you could repeat the kornblum oxidation to obtain p2p instead of the last step using NH3 resulting in the censored product

[Edited on 14-7-2012 by rannyfash]

I'd like the source to this, interesting.

Ephoton - 17-7-2012 at 23:12

sounds like a stinky sulfur run too me and
a heap of stress about lead posioning XD

otherwise superbase DMSO and off to desired target.

rannyfash - 28-7-2012 at 00:25

Quote: Originally posted by rannyfash

I'd like the source to this, interesting.

this is the source, its oc

polymerizer87 - 28-7-2012 at 18:24

Does anyone have synthetic experience with the Willgerodt Reaction with Styrene to phenylacetic acid? I'm more curious about the odor it puts out... Morpholine and styrene have a very familiar smell to them, and let's not forget sulfur. I won't attempt this reaction if it's going to bring attention to my home. I don't have any desire to carry this precursor to p2p. I just want to use up the 4 liters of morpholine and styrene that I have.

497 - 30-7-2012 at 18:57

Not quite useful for what you guys are talking about, but did you know that direct air oxidation of molten polystyrene will yield a useful amount of benzaldehyde? Keep the temp between about 280-330 in order to minimize the styrene monomer coming over with it. It won't yield a pure product out of the condenser. Using bisulfite adduct would get you nearly clean benzaldhyde though. It is by far the major oxygen containing product other than CO, CO2, and H2O. The only other things that could get caught as a bisulfite adduct are minute traces of cinnamaldehyde and acetaldehyde.

In this paper where they tested the decomposition properties of 'polycubes' (PuO2 suspended in polystyrene) it was able to produce a 28% by weight yield of benzaldehyde, plus 14% styrene, 4% toluene 2% benzene, 0.3% indane, everything else organic under 0.1%. And that was with highly crosslinked PS containing CeO2 as stand in for PuO2. They go on to say that crosslinking and CeO2 result in lower levels of flammable products, more char. If you used normal PS and actually optimized for benzaldehyde >40% should be possible, but no one has ever tried AFAIK. Also it has the added advantage of being a faster and lower temperature process vs inert gas pyrolysis.
http://www.osti.gov/bridge/servlets/purl/808247-zEzoGI/nativ...

I realize you might get a higher yield by a inert gas pyrolysis (or trip to the paint store) then liquid phase oxidation of styrene monomer. But that a whole second step with reagents and all that... Polystyrene and heat are just so much more cheap and available, this can't be ignored. I have no doubt people somewhere in the world would appreciate this.

roamingnome - 31-7-2012 at 17:04

yes, i was reading about strait destructive pyrolysis to crude benzaldehyde some where else. From what i gathered the styrene can be self polymerized with oxygen, and this intangels oxygen in the polymer.

When it is thermally decompositioned the aldehyde can be significant.

A metal oxide catalyst may direct the reaction products even more.

rannyfash - 12-8-2014 at 17:53

just another quick thought, ozonolysis of liquid styrene produced from the dry distillation of polystyrene, benzaldehyde and formaldehyde

[Edited on 13-8-2014 by rannyfash]

cmos6667 - 25-5-2015 at 15:02

Entirely OTC-ish:

Benzaldehyde, Ethyl acetate, NaOH, NaBH4, H2SO4:

Benzaldehyde + Ethyl acetate + NaOH (tiny amount, e1cb) --> diketone
diketone + NaBH4 --> glycol
glycol + H2SO4 --> P2P (https://www.erowid.org/archive/rhodium/chemistry/peracid.htm...)

byko3y - 25-5-2015 at 16:46

You might have already known that NaOH does not dissolves in ethyl acetate, neither it does in benzaldehyde, and it reacts irreversibly with ethyl acetate in presence of water, and gives Cannizzaro reaction with benzaldehyde.

clearly_not_atara - 25-5-2015 at 18:35

Quote:

Benzaldehyde + Ethyl acetate + NaOH (tiny amount, e1cb) --> diketone

^the expected product of the first reaction is ethyl cinnamate, not pyruvoylbenzene. The aldehyde won't act as a nucleophile unless you convert it to a dithiolane.

[Edited on 26-5-2015 by clearly_not_atara]

cmos6667 - 26-5-2015 at 10:06

ah, my bad, thanks for the info

CuReUS - 27-5-2015 at 03:06

Quote: Originally posted by cmos6667

Entirely OTC-ish:
diketone + NaBH4 --> glycol

since when did NaBH₄ become OTC

[Edited on 28-5-2015 by CuReUS]

cmos6667 - 27-5-2015 at 13:41

Doesn't OTC mean you can get it without much hassle? You can get a kg of NaBH4 for 150£ on ebay.
And yes, I think so too.

byko3y - 27-5-2015 at 16:44

I'm not sure whether customs will be happy to see sodium borohydride in the declaration, but I agree that NaBH4 is much easier to obtain and is less watcher, than LiAlH4.

cmos6667 - 28-5-2015 at 14:02

ok so what about legos? buy you some heliozimt, dissolve it in whatever ABS dissolves in, add say 2 or 3 molar equiv formic acid, reflux it for 6 hours, add methyl iodide, followed by NaOH, bam, racemic meth oil

GrayGhost - 28-5-2015 at 14:39

Styrene to P2P, it has several reactions and is not direct.
Other ways with several reactions , Styrene to Phenylacetamide to Phenylacetic Acid to P2P .

Styrene, ammonium hydroxide,sulfur,ethanol (reflux in autoclave) Chinese patent. ( Someone attemp this?)

byko3y - 28-5-2015 at 17:02

Willgerodt-Kindler with ammonia is an old well known reaction, but yes, it requires autoclave, and not everybody here has autoclave.

GrayGhost - 28-5-2015 at 17:33

Quote: Originally posted by byko3y

Willgerodt-Kindler with ammonia is an old well known reaction, but yes, it requires autoclave, and not everybody here has autoclave.

I am tempting build a autoclave with old glass bottle of 10mm thick
with turn movement ( need agitation) in hot water bath. The problem is the tap, posibility use Teflon.

http://mla-s1-p.mlstatic.com/sifon-de-vidrio-soda-la-cecilia...

The vessel is old sifon de soda ( syphon of carbonatate water) .

[Edited on 29-5-2015 by GrayGhost]

byko3y - 28-5-2015 at 22:04

The answer is simple - do not use 100 years old method without modifications. Actually, Kindler modification is all about secondary amines, while the ammonia route is called simply WIlgerodt reaction.

GrayGhost - 29-5-2015 at 11:03

Quote: Originally posted by byko3y

The answer is simple - do not use 100 years old method without modifications. Actually, Kindler modification is all about secondary amines, while the ammonia route is called simply WIlgerodt reaction.

Yes Sir, but original Willgerodt reaction take more of 20 hours

It is impractical for me.

byko3y - 30-5-2015 at 00:39

I just don't want to give you a complete answer, because you need to know more about this reaction before you can do it yourself due to possible hydrogen sulfide generation. It has really complex mechanism, but conditions and work up are much more easy. And you need no autoclave in fact.

CuReUS - 30-5-2015 at 02:49

Quote:

by the Chinese patent in the linked thread, practically no H2S is evolved unless in the hands of a fool.

nicodem said this on pg 2,so formation of H₂S can be prevented.
I don't understand why people are going crazy trying to produce phenylacetic acid like this,when a UV catalysed,photo semi-benzilic rearrangement of chloracetophenone would give it to them

byko3y - 30-5-2015 at 03:34

Maybe because yield of Favorsii rearrangement of α-chloro-acetophenone is 25% in acetone, 50% in acetonitrile, and no reaction in alcohol (reduced back to acetophenone). But it works much better for activated aromatics.

Templar - 6-6-2015 at 20:40

Quote: Originally posted by rannyfash

I believe someone tried this is in a pressure reactor, substitution of the Br group with an anime by dry ammonia in a solvent, except it was for the methylenedioxy amphetamine version. Jon I think? Well I remember there being a big long 5pg+ thread on thevespiary of people trying it and saying it didnt work. Maybe the MD bridge was too fragile under high temp/pressure. But looking at the history of amphetamine synthesises going back to the 19th and 20th centuries it should work.

Its good that this thread didnt devolve into holier-than-thou chemists sitting on their righteous high horses. No one is being forced to take drugs, and that's if the chemist is manufacturing them in large scale quantities to sell. The war on drugs is a sham, and anyone who believes it is for the good of the people is a fool; an absolute pseudo intellectual, regardless of whatever university paper slip you have.

RE sourcing chemicals, borohydride and LAH can be easily (although at varying degrees of economy) sourced from china. Some countries, like NZ and australia, will simply confiscate any white powders they come across regardless of whether or not they test positive for illegal drugs. They can then demand money for testing for YOU to prove YOUR innocence, 500-1000$. I do not know if other larger countries can get away with this (looking at you america) because it is illegal for the state to do such a thing if the legal system has the onus to prove something is illegal.

Borohydride and then 10% Pd/C can be had relatively readily and cheaply from china. It can offer a higher yielding, cleaner, cheaper and less dangerous synthesis than using LAH. But obviously it does not have the same scope of application as LAH.

I had ~30g of 10% Pd/C locked in customs for 4 months until suddenly it turned up one day when the pricks realized that a black moist powder didn't have drugs mixed into it.

Until you have tried sourcing chemicals from china, you cannot say that borohydride, LAH etc are impossible to source. Dont go asking for acetic anhydride, p2p, piperonal etc though. China may be lax, but theyre not as lax as some people would like!

For smaller, specialized chemical amounts its best to try out eastern yurop/russian etc sellers on auction sites.

Amphetamines are marvelous for intelligent, disciplined people to use sometimes for performance enhancement. Good luck with the synth guys just my 2c.

leom8888 - 31-10-2015 at 16:05

I want to say is that you are too cool

Waffles SS - 1-11-2015 at 08:50

Reaxys search of all possible ways for synthesis Phenylacetone (P2P)
(Please don use it for illegal purpose)

Attachment: P2P.pdf (1.9MB)
This file has been downloaded 2911 times

[Edited on 1-11-2015 by Waffles SS]