Sciencemadness Discussion Board

aldehydes and ketones by dry distillation: practical details?

Polverone - 9-4-2008 at 21:07

There are thousands of chemistry textbooks and reference manuals that refer to the dry distillation of the calcium (sometimes strontium, barium, lead...) salts of carboxylic acids with formates or acetates to yield the corresponding aldehydes or ketones. I imagine that this process is generally low-yielding and gives rise to a mixture of products, except in special cases (e.g. acetone from barium acetate).

Unfortunately, I have been hard-pressed to find detailed accounts of reactions of this sort that give quantitative information or instructions for best results. Is it the case that there is no real wrong (no real right, either) way to do it? I have been scouring Google Books, sure that I would find some practical examples in older material, but the older books too seem to describe the process in all of two sentences. One pharmaceutical text described the preparation of acetophenone ("hypnone") from calcium acetate and benzoate. The yield was stated to be 6%. If that's typical, it is no wonder that chemists abandoned the technique long ago. Still, I would like to read more about this universally-known, poorly-described technique.

Does anyone know of books or papers, especially those available through free online collections, describing dry distillations of this sort in more detail? Acetone production from acetates is easy to find, but experimental/practical details for other preparations seems to be very rare.

Edit: The Owens College Course of Practical Organic Chemistry
by Julius Berend Cohen (available on Google Books) gives a dry distillation preparation of acetophenone as preparation XXV. Unfortunately, it does not state an expected yield.

[Edited on 4-9-2008 by Polverone]

LSD25 - 9-4-2008 at 21:22

What exactly are you after? Am I reading this correctly, you just want articles on the thermal decarboxylative ketonization, etc. of carboxylic acids?

Cool, here's 20-odd articles:

http://www.4shared.com/dir/5890049/b2d69898/Thermal_Decarbox...

The one by [sorry, had em mixed up] Glinski, et al is fucking interesting

[Edited on 9-4-2008 by LSD25]

not_important - 9-4-2008 at 21:25

I've seen some detailed descriptions in older books, I'll see what I can dig up out of my collection.

The yields did tend to be bad, but that was true of a lot of Victorian era organic chemistry; there are numerous descriptions of preparations based on destructive distillation methods, giving several identified (or at least named) compounds and more unnamed, un-investigated ones as well.

The vapour phase method, using heat ThO2 or other oxides, seemed to replace the simple dry distillations around or after WW-I. When comparisons could be made, the vapour phase seemed to give better yields.

Polverone - 9-4-2008 at 21:39

The Groggins paper is very interesting, though it's not really about dry distillations. One of the papers led, in a footnote, to the following enlightening JCE article: http://www.jce.divched.org/Journal/Issues/1961/Jun/jceSubscr...

It's part of a series on errors in textbooks and the gist of it is that, contrary to the impression given in many books, dry distillation is not preparatively useful except in special cases. There is little literature in existence that gives details of these kinds of preparations, which is probably why I had such a hard time finding any on Google Books.

LSD25 - 9-4-2008 at 21:53

The review on the first page of that link, thanks to whoever found it, I have no idea who that was... is very fucking interesting, especially as it details the requirements of the reaction, how it works and how it can be tweaked to give better performance and/or results.

Polverone, need someone with a J.Chem.Ed subscription to download that link - cos I cannot get it without a password.

PS Yeah, I had Groggins and Glinski mixed up, but the very best of 'em is the microreview. From what I found on Google searching the full title - thanks are owed to Nicodem.



[Edited on 9-4-2008 by LSD25]

Polverone - 9-4-2008 at 22:45

Here's the JCE paper: https://www.sciencemadness.org/scipics/JCE1961p0300.pdf
It seems to cast doubt on at least the cyclopentanone example from the microreview; apparently adipic acid doesn't need much catalytic help to transform. It is rare that other acids would transform so readily.

Nicodem - 9-4-2008 at 22:55

I know of no textbook that describes any such ketonization experiment (well, except for the one in Vogel's, but that is a catalytic method with ThO2). I would guess the reasons why this reaction is one of the old forgoten one is because:

- organic chemists don't like do thermolytic reactions (especially if it involves a Bunsen burner!);
- such a ketonization does not tolerate any sensitive functional groups which means it's only of any use to simple ketones which are more or less already all commercially available;
- there is always a higher yielding alternative (Friedel-Crafts acylation for aromatic ketones, Dakin-West reaction for amino acids and arylacetic acids, oxidation of secondary alcohols, Claisen condensation for beta-keto esters, and many, many others).
- the reaction is ancient history and today's professional chemists have a certain mentality that it is only worth doing whatever is the latest fad (generally, if even industrial chemists abandon a reaction, it becomes completely forgotten for the researchers as well, and that's why you only see this acetates to acetone example in school books – though it appears that the catalytic version is not completely abandoned by the industrial chemists).

I'm afraid one of the best sources for references regarding this reaction is this forum. A lot has been posted in regard to this type of ketonization. I remember Organikum posted some papers (using Fe carboxylates), I posted a bunch of patents for preparing aldehydes via formates, and now LSD25 with his large compilation of papers.

To Trilobite: list of patents about employing formates

[Edited on 10/4/2008 by Nicodem]

trilobite - 9-4-2008 at 23:01

I'll have a look and see what I can find out. Something that will most likely improve yields is having a constant current of an inert gas through the distillation setup to flush the product out of the apparatus to reduce decomposition, carbon dioxide will do. See http://www.erowid.org/archive/rhodium/chemistry/p2p.paa-ca.h....
Alternatively performing the reaction at a slight vacuum might help: http://www.erowid.org/archive/rhodium/chemistry/p2p.paa-pb.h....

I suppose that in the synthesis of formaldehyde by dry distillation of calcium formate the side reaction that most affects the yield is

H2CO --> H2 + CO

Nicodem: In which thread did you post those patents? I can't find them right now and you have so many posts to go through.

[Edited on 4/10/2008 by trilobite]

S.C. Wack - 10-4-2008 at 01:55

Quote:
Originally posted by LSD25
decarboxylative ketonization

You seem to be the only person in the world using that phrase.

Searches using the phrase "ketonic decarboxylation" will however yield some articles, leading to several older articles, leading to...

It might be easier to search for specific cpds. of interest and narrow it down to preparation in this manner.

A lot but not all of this (straight-up calcium and barium salts) will be older, in French or German, and may not really specify yield or much of conditions as typical of the era.

EDIT: I was just looking at one of the better papers for acetone production from acetate [IEC 16, 1133 (1924)] and was struck by the similarity of its opening sentence with Polverone's comments:
"Anyone who has had occasion to consult the literature dealing with the manufacture of acetone by the dry distillation of acetate of lime must have been struck, not only by the vagueness of the descriptions and the paucity of the figures, but also by statements that are actually incorrect."

OK then, "decarboxylative ketonization" is unique to this site, not the poster.

[Edited on 10-4-2008 by S.C. Wack]

LSD25 - 10-4-2008 at 03:07

Works for me, and it appears to lead to some hits:

http://tinyurl.com/4bkl26

It may not be technically correct, or usual, but it works for me, after all, the most important thing from my perspective is that I can find my files when I want 'em (you'll note that the term is not used, or I don't think so, in the hits, but the combination of the terms is in the keywords of some of the hits?).

Nicodem - 10-4-2008 at 03:39

I thought it was me who invented that phrase. :P
Indeed in the literature it is most commonly referred just as ketonization which is not particularly correct since ketonization is a general term for all formations of ketones. Less commonly it is referred with phrases like catalytic–pyrolytic ketonization or pyrolytic ketonization, pyrolysis / thermolysis of carboxylate salts and the one S.C. Wack used.

According to some kinetic studies It appears there are two different mechanisms of these ketonizations. One is observed in the thermolysis of metal carboxylates and catalytic processes where earth alkali metal carbonates or oxides are used (MgO and similar) :
Quote:
Kinetics and mechanism of thermal decomposition of lithium, sodium, and barium acetates.
Yakerson, V. I.; Rubinshtein, A. M.
Kinetika i Kataliz, 2 (1961), 172-178.

CA abstract: Prepn. of ketones by thermal decompn. of Li, Na, and Ba acetates and prepn. of CH4 by thermal decompn. of NaOAc are studied. Prepn. of ketone from NaOAc (at 419-74) and LiOAc (at 352-415°C) occurs in the melt and proceeds by 2nd-order kinetics. Ba(OAc)2 decomps. in the solid phase in accordance with the topokinetic Erofeev equation (CA 41, 4027c). The relation between the rate consts. and temps. is described by the Arrhenius equation. The energy of activation (E) and preexponential factors were calcd. E of prepn. of ketones from the acetates agree with E of vaporphase prepn. of ketone from AcOH on carbonates of the corresponding metals. This fact holds good also in the prepn. of CH4 from NaOAc and from AcOH on Na2CO3. The exptl. results and literature data verify the concept of the formation of a cyclic 4-membered activated complex and of the mol. mechanism of ketone prepn. A scheme is suggested for the prepn. of CH4 from NaOAc with participation of H2O included in the activated complex. A compensation effect exists for both types of decompn. of the studied acetates.

Mechanism of the ketonic pyrolysis of aliphatic barium carboxylates.
Noszko, L.; Szammer, J.; Szabolcs, A.; Otvos, Laszlo.
Radiochemical and Radioanalytical Letters, 5 (1970) 265-274.

Abstract: The formation of asym. ketones in the pyrolysis of mixts. of 2 aliphatic Ba carboxylates RCO2M, such as Ba acetate-1-14C and Ba propionate, butyrate, isobutyrate, trimethylacetate, phenylacetate, resp., proceeds by a concerted process with the structure of the transition state I. Since either carboxylate group of reactants may take a share in producing the carbonyl group of the asym. ketone, 2 activated complexes may be formed. The 14C isotope technique being used, the ratio of activated complexes can be calcd. from the molar radioactivities of products even in the case of carboxyl group exchange.


The ketonizations using tetravalent transition metal oxides (ThO2, ZrO2, etc.) seems to proceed trough a different mechanism:
Quote:
Vapor-phase catalytic ketonization of acetic acid on oxides of quadrivalent metals and BeO.
Yakerson, V. I.; Fedorovskaya, E. A.; Klyachko-Gurvich, A. L.; Rubinshtein, A. M.
Kinetika i Kataliz, 2 (1961) 907-915.

CA abstract: Catalytic vapor-phase ketonization of AcOH is studied at 286-460°C; on TiO2, ZrO2, SnO2, CeO2, and BeO. The apparent activation energies (E), preexponential factors (log k0), and sp. catalytic activities of the catalyst were detd. The sp. catalytic activity at all temps. follows the series CeO2 < ZrO2 > TiO2 > SnO2 (>BeO); E:SnO2, CeO2, TiO2 > ZrO2(>BeO); and log k0: CeO2 > SnO2, TiO2 > ZrO2(>BeO). The phase compn. of the oxides of the quadrivalent metals is not changed during the ketonization, their form and appearance remain the same. The catalytic ketonization of AcOH on the oxides of the quadrivalent metals occurs on the hydrated surface of the catalyst, whereas for alk. earth oxides (less BeO) and for alkali metal carbonates this process occurs within the crystals. The mechanism of AcOH ketonization on Be, Ti, Zr, Sn, and Ce oxides is attributed to formation of a cyclic 6-membered activated complex with quasi-isoenergetic redistribution of bonds. The concept of the surface hydration is discussed. Of considerable importance is the value of the sp. surface and porosity of the ketonization catalysts. The surface decreases with time. Sp. catalytic activity decreases or increases with change of the surface area. Increase of the surface is connected, apparently, with its breakdown by the action of AcOH, this interaction being a function of temp. 25 references.


So we are actually dealing with two type of ketonization reactions.

Here is an archive with some papers related to ketonization. Titles:
Ketonization of Carboxylic Acids by Decarboxylation: Mechanism and Scope (micro review)
Ketonic Decarboxylation Catalysed by Weak Bases and Its Application to an Optically Pure Substrate
The Ketonic Decarboxylation Reaction: The Ketonic Decarboxylation of Trimethylacetic Acid and Isobutyric Acid
Decarboxylation Studies. II. Preparation of Alkyl Phenyl ketones
Decarboxylation studies. III. Rate of ketonic decarboxylation of lead(II) octanoate

As for the experimental procedures here is one example:
Quote:
General Procedure: The dry distillation was carried out in a 50 mL round-bottomed flask fitted with a 10-cm Vigreux column connected to a microdistillation apparatus and the gas outlet was connected to a gas burette. The flask was heated with a hemispherical heating mantle and the reaction time was started when 350 °C reaction temperature had been reached (after ca. 25 min). Adipic acid (10.0 g, 68.4 mmol) was placed in the flask together with a magnetic stirring bar and the corresponding amount of base. The heating was started and the progress of the reaction was followed by measuring the gas evolution. When no gas was produced anymore, the reaction was stopped, the two phases separated and the organic layer analysed by GC analysis, GC-MS and NMR spectroscopy. The purity of the cyclopentanone was in all cases higher than 99%. Traces of unchanged adipic acid could be detected by 1H NMR spectroscopy.
In the case of the re-use of the residue, adipic acid (10.0 g, 68.4 mmol) was placed in the flask together with NaOH (496 mg, 12.4 mmol) and distilled until gas production ceased. A new 10.0 g portion of adipic acid was placed in the flask and the distillation continued. Over seven cycles 36.4 g (90%) of cyclopentanone was obtained as a colourless liquid from 70.0 g of adipic acid.

from Eur. J. Org. Chem. (2004) 2036-2039 (also in the attachment)


EDIT: Uploaded the papers on the forum's FTP instead of having it as an attachment, which should fix the usual problem with the attaching archive files.

While I'm edditing I might also add that US3660491 is particularly interesting since it claims ~15mol% Co(OAc)2 catalyses the ketonization of p-methylbenzoic acid with 20 equivalents 98% acetic acid giving a 16% yield of p-methylacetophenone after 9h reflux. Mind that the reflux temperature is only ~120°C!

[Edited on 10/4/2008 by Nicodem]

not_important - 10-4-2008 at 04:14

Quote:
Originally posted by trilobite
Something that will most likely improve yields is having a constant current of an inert gas through the distillation setup to flush the product out of the apparatus to reduce decomposition, carbon dioxide will do.


Which may kave something to do with why the gas phase modifications seemed to give higher yields.

Nicodem - last file in your RAR is being reported as broken. This may be the established software bug, perhaps adding a dummy 1K file as the kast file in the RAR might help.

Polverone - 10-4-2008 at 20:56

Thanks for all of the information. I expected that a lot of the details (if ever recorded) would be buried in older German works, but I would have thought that at least some English-language works from the same era would treat this preparative method in detail. I don't expect it to really be a convenient method, but it is one that is easily accessible to hobbyists. Plus there's my pure, abstract curiosity about a method that's widely known and little-used.

It seems that Michael Renz really loves preparing cyclopentanone(s) from adipic acid(s) but I'm skeptical of how much that can be generalized, given his admission that even pure adipic acid produces a reasonable yield of cyclopentanone on prolonged distillation. It seems that most dry distillations do not proceed so readily and neatly.

Sydenhams chorea - 7-10-2012 at 17:01

The JCE article "Textbook errors" posted earlier in this thread stated that:
Quote:

The statement that aldehydes are obtained by pyrolytic decomposition of mixed salts of calcium formate and higher calcium carboxylates seems to be based upon one report over a century old, that of Piria (13)

and gives the reference...
(13) PIRIA, M., Ann. chim. phys., (3) 48, 113 (1856)

...while a casual browsing of the orgsyn website revealed several papers which use this technique of obtaining the corresponding aldehydes from the dry distillation of a mixture of the calcium salt of carboxylic acids and calcium formate:

1-naphtaldehyde
Lugli, Gazz. chim. ital., 11, 394 (1881).

2-naphtaldehyde
Battershall, Ann., 168, 116 (1873).
Sah, Rec. trav. chim., 59, 461 (1940).

propionaldehyde
Linneman, Ann. 161, 21 (1872)

n-hexaldehyde
Lieben and Janecek, Ann. 187, 130 (1877).

3-phenylpropionaldehyde
Miller, W.; Rohde, G. Ber. 1890, 23, 1079.

Most of these (except for 2-naphtaldehyde and 1-hexaldehyde) I include attached with this post.

Attachment: Gazz_chim_ital_ 11_394_1881-naphtaldehyde.pdf (346kB)
This file has been downloaded 590 times

Attachment: Ber_1890_23_1079-82-Hydrozimmtaldehyd.pdf (342kB)
This file has been downloaded 774 times

Attachment: Ann_Chim_Pharm_161_1872_21-30-propionaldehyde.pdf (768kB)
This file has been downloaded 808 times

[Edited on 8-10-2012 by Sydenhams chorea]

aryl cyanides via K4Fe(CN)6

tetrahedron - 8-10-2012 at 12:42

reading the italian paper what i found more interesting was the conversion of potassium naphthalenesulfonate to naphthonitrile by dry distillation with potassium ferrocyanide. could this be applied to benzenesulfonate as well (to get benzonitrile)?

leu - 11-10-2012 at 17:17

Quote:
Does anyone know of books or papers, especially those available through free online collections, describing dry distillations of this sort in more detail?


The attached article:

The Mechanism of the Ketonic Pyrolysis of Calcium Carboxylates
C. C. Lee , J. W. T. Spinks
J. Org. Chem., 1953, 18 (9), pp 1079–1086
DOI: 10.1021/jo50015a003
Publication Date: September 1953

provides a description of the mechanism and other relevant details of this particular synthetic approach in English :cool:



Attachment: jo50015a003.pdf (227kB)
This file has been downloaded 1568 times

Random - 13-10-2012 at 04:52

i have tried distillation, very small amount of calcium acetate & ferric benzoate

produced some liquid with "chemical lab, phenolic" smell, maybe acetophenone

Nicodem - 13-10-2012 at 05:14

Quote: Originally posted by tetrahedron  
reading the italian paper what i found more interesting was the conversion of potassium naphthalenesulfonate to naphthonitrile by dry distillation with potassium ferrocyanide. could this be applied to benzenesulfonate as well (to get benzonitrile)?

In the referenced Zeitschrift für Chemie the authors did not use potassium ferrocyanide, but KCN with potassium beta-naphthalenesulfonate. See:
Ueber ß-Cyan- und Carboxylnaphthalin
Zeitschrift für Chemie, 1869.

The reaction of alkali cyanides with alkali arylsulfonates was already discussed on the forum previously. There you can find another reference where K4Fe(CN)6 was used with success. After the example in the Gazzeta chimica Italiana, this makes for an additional confirmation that potassium ferrocyanide works as well.

[Edited on 13/10/2012 by Nicodem]

tetrahedron - 13-10-2012 at 14:36

yes, i noticed that the process of Merz & Mullkäusen uses potassium cyanide, but the Italian chemist explicitly says he used a variation by Witt, which is probably where the switch to ferrocyanide lies..unfortunately he doesn't provide a reference so i haven't been able to find it. your post in the linked thread makes it sound feasible, although low yields and impurities due to pyrolysis have to be expected (these might not be so important as both papers go on to synthesize the corresponding carboxylic acid or its salt, which can be easily extracted). i'm curious as to what they mean by the Sandmeyer process ("which involves large vols. of soln")..diazotization involves quite a different route so maybe they mean something else?

[Edited on 14-10-2012 by tetrahedron]