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Author: Subject: The Short Questions Thread (4)
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[*] posted on 10-11-2013 at 12:15


Seems like you'd first need to hydrolyze it to monomers, and then convert it to dioxane via some means such as heating with sulfuric acid. Those individual steps should be easy enough to research, I know that the latter at least has been discussed on this forum.



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[*] posted on 17-11-2013 at 15:54
Question


would calcium hydroxide work for a base catalysed hydrolysis of acetylsalicyclic acid to salicyclic acid?
is there any way to know when the reaction has come to completion?
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[*] posted on 17-11-2013 at 16:16


Quote: Originally posted by confused  
would calcium hydroxide work for a base catalysed hydrolysis of acetylsalicyclic acid to salicyclic acid?
is there any way to know when the reaction has come to completion?


Boiling water is enough to get the decomposition going, so I'm going to say "yes."




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[*] posted on 17-11-2013 at 16:20


If I'm going to guess, calcium salicylate won't be very soluble. Boiling water works, but adding a few drops HCl speeds it up and makes the workup easier.



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[*] posted on 19-11-2013 at 17:24


Where can I find general a procedure on forming ketone and aldehyde sodium bisulfite adducts?
http://www.erowid.org/archive/rhodium/chemistry/eleusis/bisu... This is the closest I have gotten.

I plan on separating the benzaldehyde from almond extract. Im going to try with acetone also.




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[*] posted on 27-11-2013 at 08:06


I have a quick question regarding removing the acetyl group from n-acetyl-4-piperidone what I am wondering is were I to reflux with a slight molar excess of potassium hydroxide will I shed the acetyl leaving the 4-piperidone in tact? If you have any experience I would love to hear from you as well if you might have any pertinent refs all aid would be appreciated.
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[*] posted on 28-11-2013 at 14:29


Does anyone know where I can find a good preparation for:

Diethyl azodicarboxylate

Thanks!




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[*] posted on 28-11-2013 at 15:32


Quote: Originally posted by plante1999  
Does anyone know where I can find a good preparation for:

Diethyl azodicarboxylate

Thanks!


You can see it here, thanks me latter:

http://www.orgsyn.org/Content/pdfs/procedures/CV4P0411.pdf





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[*] posted on 29-11-2013 at 11:19


I distilled technical quality toluene, to keep it completely anhydrous I added a few thin flakes of pure Na.
two days later they look like this:
WP_20131129_001.jpg - 80kB
what could there be in redistilled toluene that turns brown in contact with Na or NaOH?

Do I need to distill it again, or can I get away with filtration? (400ml)




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[*] posted on 29-11-2013 at 12:36


Seems like sodium oxide - I get that brown/yellow finish on my sodium as well. Not in toluene, though.



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[*] posted on 30-11-2013 at 12:02


Ok, thanks. Do I need to re-distill it or can I just filter the floating ''stuff'' out?



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[*] posted on 30-11-2013 at 13:18


Quote: Originally posted by Pyro  
Ok, thanks. Do I need to re-distill it or can I just filter the floating ''stuff'' out?

Should probably re-distill it, but either way works. The 'stuff' should also keep your solution dry, so best to keep it in there long-term.




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[*] posted on 30-11-2013 at 13:20


the Na sinks in toluene, but the stuff looks like scurf and floats around :)



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[*] posted on 30-11-2013 at 15:50


How would FeCl3 react with sodium acetate?



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[*] posted on 30-11-2013 at 18:00


Quote: Originally posted by bismuthate  
How would FeCl3 react with sodium acetate?


Probably through hydrolysis. Fe3+ + H2O + OAc- -> Fe(OH)2+ + HOAc.

With enough acetate ion, you'll get iron(III) hydroxide precipitating.




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[*] posted on 1-12-2013 at 17:14


Question

does anyone knows where to get tert-butanol?

[Edited on 06/11/2013 by BlackDragon2712]
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[*] posted on 1-12-2013 at 17:31


I do.



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[*] posted on 1-12-2013 at 17:33


Quote: Originally posted by BlackDragon2712  
Question

does anyone knows where to get tert-butanol?

[Edited on 06/11/2013 by BlackDragon2712]

U2U sent regarding potential availability. Unfortunately, I have no idea where you live...




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[*] posted on 1-12-2013 at 20:40


Quote: Originally posted by I Like Dots  
Where can I find general a procedure on forming ketone and aldehyde sodium bisulfite adducts?
http://www.erowid.org/archive/rhodium/chemistry/eleusis/bisu... This is the closest I have gotten.

I plan on separating the benzaldehyde from almond extract. Im going to try with acetone also.


Check the library here. This is covered in "purification of laboratory chemicals."

I would do a fractional distillation first. You could skip the bisulfite step as most oil of bitter almond is 98% (or more) benzaldehyde.





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[*] posted on 1-12-2013 at 20:53


Quote: Originally posted by SHADYCHASE54  
I have a quick question regarding removing the acetyl group from n-acetyl-4-piperidone what I am wondering is were I to reflux with a slight molar excess of potassium hydroxide will I shed the acetyl leaving the 4-piperidone in tact? If you have any experience I would love to hear from you as well if you might have any pertinent refs all aid would be appreciated.


Try strong base in ethylene glycol or DMSO. 4-piperidone polymerizes on formation so it is sold as the dihydro-HCl. The water molecules are a formality since it is actually a diketal. Let me know how it goes or send me what you've got and I'll give you an eq amt of the product of commerce.




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[*] posted on 5-12-2013 at 15:19


Does anybody know a solvent for calcium/alkali metal carbides?



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[*] posted on 5-12-2013 at 15:25


Calcium carbide is actually an acetylide- a strong base, but one can work with it. Avoid esters and alcohols, obviously, but you need something polar or it won't dissolve. Acetonitrile is probably to acidic; acetone is too vulnerable to nucleophilic attack...I'd try THF. Even if it's not very soluble, it might disperse enough to be a good reaction medium.

For an alkali metal acetylide, you might be able to make it more soluble by adding TMEDA (tetramethylethylenediamine).

[Edited on 5-12-2013 by DraconicAcid]




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[*] posted on 5-12-2013 at 15:39


(I don't know much about organic chem so I may say something stupid)From what I have seen on SM CaC2 does not seem to react with ethanol. Might it be slightly soluble in that? I would also wonder about liquid ammonia.

[Edited on 5-12-2013 by bismuthate]




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[*] posted on 7-12-2013 at 23:03


Online sources typically state the concentration of selenium in dietary supplements to be 200 micrograms per tablet. Considering each tablet weighs considerably more than 200 ug, what's the rest?



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[*] posted on 8-12-2013 at 00:00


my guess would be binders,preservatives and flavors or sweeteners
http://en.wikipedia.org/wiki/Excipient
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