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Nicodem
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Using NaOCl on propylene should give propylene oxide directly since the intermediate chlorohydrine cyclisizes to the epoxide in basic media. The
preparation of 1-chloro-2-propanol from propylene glycol was already discussed on this forum in a thread about 2-chloroethanol preparation (there are
some references there).
Also, both regioisomeric halohydrines derived from propylene give the same aminoalcohol if used in the reaction with ammonia since the first step is
always the cyclisation to propylene oxide. So it does not matter if you use 1-chloro-2-propanol, 2-chloro-1-propanol or propylene oxide, the product
in nucleophilic substitutions is always the same. A normal SN2 on 1,2-halohydrines is not possible due to the neighboring group
participation(cyclisation to an epoxide followed by an SN2 on the epoxide ring; thus leading to retention of configuration). A similar neighboring
group participation is observed in alpha-halo-carboxylic acids (for example the reaction of 2-chloropropanoic acid with amines, etc.).
…there is a human touch of the cultist “believer” in every theorist that he must struggle against as being
unworthy of the scientist. Some of the greatest men of science have publicly repudiated a theory which earlier they hotly defended. In this lies their
scientific temper, not in the scientific defense of the theory. - Weston La Barre (Ghost Dance, 1972)
Read the The ScienceMadness Guidelines!
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MagicJigPipe
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NaOCl on propylene, eh? That would be an interesting setup. Or perhaps just a simple "bubbling through" type setup (a la chlorine and toluene) would
suffice. Then just distill...
Even though I doubt there would be information on this I will do a search tomorrow (it's late...)
Thanks for the information, Nicodem.
"There must be no barriers to freedom of inquiry ... There is no place for dogma in science. The scientist is free, and must be free to ask any
question, to doubt any assertion, to seek for any evidence, to correct any errors. ... We know that the only way to avoid error is to detect it and
that the only way to detect it is to be free to inquire. And we know that as long as men are free to ask what they must, free to say what they think,
free to think what they will, freedom can never be lost, and science can never regress." -J. Robert Oppenheimer
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S.C. Wack
bibliomaster
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| Quote: | Originally posted by MagicJigPipe
Surely, you are not in the US because I would have heard of this. |
I'd make up the fact that I'm in Bumfuck, USA by choice? (I'd move to a wet spot of WA or OR if I could afford it). I sure go to a lot of trouble to
use amerikan spellings. I traded my euros for dollars so I could post this picture featuring $1 coins that are keeping the bottle from rolling onto my
lap.
A search of Ace using the magic word propylene gives the impression that they sell Matheson product in containers a little smaller than this one.
Propylene glycol would be a lot cheaper.
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MagicJigPipe
International Hazard
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I meant no offense by it. Ace must be the only place. I have not been to the solitary Ace Hardware in my area (~25miles). Thanks, though. I shall
check this out.
I didn't notice that your info says you're in the US.
Also, I can get propylene glycol by the 5 gallon jug for ~$60. I hate that glycols are so expensive. Even ethylene glycol is $9 a gallon.
[Edited on 5-14-2008 by MagicJigPipe]
"There must be no barriers to freedom of inquiry ... There is no place for dogma in science. The scientist is free, and must be free to ask any
question, to doubt any assertion, to seek for any evidence, to correct any errors. ... We know that the only way to avoid error is to detect it and
that the only way to detect it is to be free to inquire. And we know that as long as men are free to ask what they must, free to say what they think,
free to think what they will, freedom can never be lost, and science can never regress." -J. Robert Oppenheimer
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mfilip62
pierced by a crossbow under a bridge while eating Billy goats
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I would suggest propylene glycol and HaloAcetone as starting materials!
If polyols like PG follow the same chemistry as normal alcohols once could selectively
halogenate primary or secondary -OH (secodary maybe by using Lucas reagent than
do the Finkelstein reaction to replace Cl by I and react it with desired amine!
Other route would be reacting hydroxyacetone with Hydroxylamine followd by mild reduction
or reacting HaloAcetone with desired amine (with some catalyst like DIPEA/DIEA aka Hűgins base!) folowed by transforming =O into -OH!
Mixture of isomeres is not problem.
Once you halogenate remaining -OH group you can re-arrange the molecule by Aziridinium
mechanism.
Those are by far,most easyest way I can think of for producing some,at least one of the mentioned method SHOULD WORK! (I spend whole summer
researching secondary and tartiary
halogenpropylamines)
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