Sciencemadness Discussion Board

Phenol synthesis

Practicaler - 15-4-2012 at 06:32

Hey guys i know that phenol can be prepared from aniline guys i want to know is there any way to make it from benzoic acid.

Nicodem - 15-4-2012 at 06:59

Please UTFSE before opening new threads on common topics. There already are several discussions on the synthesis of phenol. Most conclude that benzoic acid is only useful as the starting material for the synthesis of benzene. The two step synthesis of phenol from benzene is then well covered by literature. Supposedly there exists a reference in Ullmann's for the direct synthesis of phenol from benzoic acid, so you can check that out if you want.

PS: Please read the Guidelines for posting on the ScienceMadness forum.

Vikascoder - 18-4-2012 at 02:01

Why dont you buy phenol it is one of the most easily buy able chemical . It is also used as disinfectant . I read it as disinfectant on wiki pedia

barley81 - 18-4-2012 at 03:30

In some places it's hard to buy. I can't find a cheap source in the US. Phenol is expensive to ship, and all the local sources won't sell to individuals. That's why making it from other benzene derivatives would be nice...

ItalianChemist - 18-4-2012 at 12:41

Phenol can be obtained heating salicylic acid with sodium hydroxide!

Hennig Brand - 18-4-2012 at 14:46

I have a bunch of liquified phenol. According to the MSDS it should contain not less than 89% phenol, the rest water. Is there a good way of removing the water?

BTW, I am in Canada and I found the pure crystalline phenol difficult and/or expensive to buy with hazard fees, etc. The liquified stuff had no hazard fees and was much more affordable. I got a drug store to order it. I guess it is used to do chemical skin peels or some other skin treatments.



[Edited on 18-4-2012 by Hennig Brand]

Nicodem - 19-4-2012 at 05:37

Quote: Originally posted by Hennig Brand  
I have a bunch of liquified phenol. According to the MSDS it should contain not less than 89% phenol, the rest water. Is there a good way of removing the water?

If water is the only thing to remove there, then you can just dry it azeotropically. You can try to dissolve in isopropanol and rotavap. You can repeat with one or two additional portions of isopropanol to make sure. If you still don't get it to crystallize in a refrigerator, then it might be impure and needs recrystallization (check the literature for the solvent) or vacuum distillation.

mycotheologist - 19-4-2012 at 11:21

Wouldn't a simple borohydride reduction do it?

ThatchemistKid - 19-4-2012 at 14:23

Well, no that would give you benzyl alcohol. One could use acetophenone and preform a dakin reaction. The phenyl group having a much higher propensity to migrate than the methyl would give phenoxide (which could them be acidified) as the major product.

ThatchemistKid - 19-4-2012 at 14:26

also If i recall correctly sodium borohydride does not react with esters or free acids readily usually one uses borane for the reduction of an acid to an alcohol.