Author Topic: Benzoic Acid via Toluene  (Read 3070 times)

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timsong

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Benzoic Acid via Toluene
« on: November 22, 2001, 11:50:00 PM »
Here is some detailed info on making benzoic acid from otc UK chemicals :-

Mix the following chemicals in a flask with vertical water condensor attached (reflux setup).

Toluene - 3 cubic centimeters
Potassium Permanganate - 10 grams
Dilute Sodium Hydroxide Solution - 20 cubic centimeters

Reflux for 3 to 4 hours until oily toluene disapears.Then cool and filter the manganese (IV) oxide from the solution. Now by addition of concentrated HCl, benzoic acid will precipitate. Either filter and re-crystallize the benzoic acid from hot H2O, or extract the benzoic acid with ether and evapourate.

Some benzoic Acid Uses :-

Mild Local anasthetic
Calcium Salt used in making acetophenone and benzophenone
Food preservative (sodium salt)




PrimoPyro

  • Guest
Re: Benzoic Acid via Toluene
« Reply #1 on: November 23, 2001, 01:11:00 PM »
Can benzoic acid be oxidized to phenol, or only benzaldehyde?

Vivent Longtemps la Ruche! STRIKE For President!

hest

  • Guest
Re: Benzoic Acid via Toluene
« Reply #2 on: November 23, 2001, 01:35:00 PM »
It can bee reduced to the aldehyde.
Phenol is a differen thing.

PrimoPyro

  • Guest
Re: Benzoic Acid via Toluene
« Reply #3 on: November 23, 2001, 02:00:00 PM »
I know the difference.

YOU simply misunderstand.

I mean: Can benzoic acid be oxidized to phenol, not a phenol, but phenol, as in carbolic acid, hydroxybenzene, etc., OR can only benzaldehyde be subjected to this conversion, PhCHO --> PhOH.

The reason for asking: If benzoic acid also works, then PhCOOH --> PhOH. If not, then I was thinking the obvious: PhCOOH --> PhCHO --> PhOH.

So now you understand my question.

                                                PrimoPyro

Vivent Longtemps la Ruche! STRIKE For President!

hest

  • Guest
Re: Benzoic Acid via Toluene
« Reply #4 on: November 23, 2001, 02:16:00 PM »
I see.
The Darkin reaction is posible on both esters and aldehydes as loong as you have a OH/NH2 group ortho or para.
(boil the ester/aldehyde in H2O2 and OH-)
So at least ArCOOH->ArCOOR->ArOH is posible :)

PrimoPyro

  • Guest
Re: Benzoic Acid via Toluene
« Reply #5 on: November 23, 2001, 02:25:00 PM »
God damn it.

Every time lately that I go back and read my posts again, I sound bitchy. I need more emoticons. Sorry if I seem bitchy, Im really not. Just need a change of writing style is all. Thank you.

I didnt know about that reaction. Thats interesting. Thanx, you have given me something new to think about.

                                               PrimoPyro

Vivent Longtemps la Ruche! STRIKE For President!

hest

  • Guest
Re: Benzoic Acid via Toluene
« Reply #6 on: November 23, 2001, 02:45:00 PM »
All forgiven my friend ;)

Antoncho

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Re: Benzoic Acid via Toluene
« Reply #7 on: November 24, 2001, 07:39:00 AM »
Hey guys, glad to see you're OK - i'd hate to see you two quarrel! ;)

As for the route itself - do i understand it correctly, that salicylic acid (ester) could bee converted to catechol/guaiacol?

And

The Darkin reaction is posible on both esters and aldehydes as loong as you have a OH/NH2 group ortho or para.
(boil the ester/aldehyde in H2O2 and OH-)



will any electron-donating group do (say, MeO-), and what is the preferred rxn time/H2O2 conc.'n ?

Thank you in advance,

Antoncho


Antoncho

  • Guest
Re: Benzoic Acid via Toluene
« Reply #8 on: November 25, 2001, 08:29:00 AM »
Well i did a search and found a couple of very interesting procedures - but in none of them a straight acid was used, AMOF, i wasn't able to find any that used anything other than benzaldehydes.

OTOH, i found some pretty interesting stuff.  1st of all, it turns out that polyphenols may bee made via this method - check out these links:

http://orgsyn.org/orgsyn/prep.asp?prep=cv3p0759



it describes prep'n of 1-methylpyrogallol from o-vanillin. And

http://orgsyn.org/orgsyn/prep.asp?prep=cv1p0149



this one describes making of catechol from salycilic aldehyde.

And there also was one amazing patent that deals with polyformylation/polydakinization of various compounds 8)  8)  8)  But it deserves a separate thread.

Still - can this rxn bee used on plain acids and what's its mechanism? Please, respond if you know.

Antoncho

Natrix

  • Guest
Re: Benzoic Acid via Toluene
« Reply #9 on: November 25, 2001, 08:36:00 PM »
timsong: this looks good, too

C6H5-CH3 + 3 NaClO -> C6H5-COOH + 3 NaCl + H2O

DRP 377990 (1915)

Does anybody know where to find the old DRP ?

Rhodium

  • Guest
Re: Benzoic Acid via Toluene
« Reply #10 on: November 25, 2001, 09:23:00 PM »

timsong

  • Guest
Re: Benzoic Acid via Toluene
« Reply #11 on: November 25, 2001, 09:40:00 PM »
Natrix, the numbers add up, looks very simular to a synth I came across for making benzyl chloride !!!
Would it work with calcium hypochlorite ??

Thanks for the patent link Rhodium, but I will have to translate it from German to understand.

I will translate and post !!

timsong

  • Guest
Re: Benzoic Acid via Toluene
« Reply #12 on: November 25, 2001, 10:48:00 PM »
ARRRRR !

I have just spent an hour trying to translate this doc, and all I am ending up with is a load of crap, (half of the doc is probably waffle anyway !).

Ze Kant Bee Fukinz Arzed wiz it n ze more !!

Calling German Hive Users ----- Help !!!!

hypo

  • Guest
Re: Benzoic Acid via Toluene
« Reply #13 on: November 26, 2001, 11:09:00 AM »
the patent talks about saving money by doing the oxidation with hypochlorite and a little permanganate (as opposed to using only permanganate).

Example 1
---------

1000 parts sodium hypochlorite solution with 75 parts active chlorine, 20 parts NaOH, 40 parts toluene and 10 parts permanganate are thoroughly mixed with heating for multiple hours until there is no more chlorine produced and the reduction of permanganate to manganese superoxide [MnO2 ??] is complete. When the oxidation is finished, excess toluene is removed with steamdistillation [not too sure] and the low amount of manganese superoxide is filtered off. Benzoic acid is gained by concentrating and acidifying the solution. The product is free of chlorine and the yield is nearly quantitative.


Example 2 oxidizes naphtaline to phtalic acid.

timsong

  • Guest
Re: Benzoic Acid via Toluene
« Reply #14 on: November 26, 2001, 12:14:00 PM »
Thanks Hypo !

PrimoPyro

  • Guest
Re: Benzoic Acid via Toluene
« Reply #15 on: November 27, 2001, 04:11:00 AM »
hypo: PLEASE post example two, oxidation of naphthalene to phthalic acid!

Ive been looking this over with HgSO4 and H2SO4, and a new process would be much appreciated!

Vivent Longtemps la Ruche! STRIKE For President!

foxy2

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Re: Benzoic Acid via Toluene
« Reply #16 on: November 27, 2001, 04:18:00 AM »
Yea Example Two!!!

Are the parts mass or Molar?


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Rhodium

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Re: Benzoic Acid via Toluene
« Reply #17 on: November 27, 2001, 09:06:00 AM »
In such an old patent, the parts are definitely by weight.

hypo

  • Guest
Re: Benzoic Acid via Toluene
« Reply #18 on: November 27, 2001, 10:56:00 AM »
ok... sounds like an industrial process, but there you go:

Example 2
---------

Into a stirred mixture of 1000 parts H2O, 150 parts NaOH, 10 parts of a melt of manganese superoxide and NaOH and 20 parts naphtaline, with or without solvent, is introduced a rapid stream of chlorine. The temperature depends on the speed of the chlorine introduction. After having introduced approximately 80 parts chlorine, stirring is continued until the permanganate is completely reduced. The excess naphtaline is removed with steam distillation [Abblasen mit Wasserdampf??], the manganese superoxide filtered off and the phtalic acid gained by acidifying the solution. Yield is nearly quantitative, the product is chlorine free.

Similarly nitro-toluols can be oxidised to nitro-benzoic-acids and m-methyl-cresole to m-methoxy-benzoic-acid

maybe that part of the maintext helps:
It is not necessary to start with sodium hypochlorite. The oxidation process can be perfomed with similar success by introducing chlorine into the alkaline oxidizing solution or suspension in presence of manganate or permanganate with or without heating. On the other hand the presence of alkali from start to finish is vital. A melt of manganese superoxide and NaOH can be used instead of permanganate. Finally hypobromites can be used instead of hypochlorites.

Natrix

  • Guest
Re: Benzoic Acid via Toluene
« Reply #19 on: November 27, 2001, 10:20:00 PM »
Hm, 1000 parts sodium hypochlorite and only 40 parts toluene. Maybe it would be better to oxydize toluene by oxygen in the presence of cobalt stearate.