Zinc
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Synthesis of Acetophenone by pyrolisys
I know that acetophenone can be made by pyrolysis of a mixture of Ca acetate and Ca benzoate. Unfortunately my access to chemical literature is
extremely limited so I could not find references to that.
So did anyone try that method? What were the yields and how hot must it be heated?
Both Ca acetate and Ca benzoate could be easily made with no hard to get reagents. Ca acetate by dissolving CaCO3 in acetic acid and Ca benzoate by
adding a conc. CaCl2 solution to a conc. Na benzoate solution. Since Ca benzoate is weakly soluble in water at room temp. (2.72 g/100 mL) it would
precipitate.
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UnintentionalChaos
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You'll find plenty of references online to using lead acetate for making phenylacetone by this process. You've just shortened it by a carbon.
There is a very old thread on making cyclopentanone via an intramolecular version of this reaction using barium compounds as catalyst. I do not know
if this is workable for this reaction though.
http://www.sciencemadness.org/talk/viewthread.php?fid=10&...
Department of Redundancy Department - Now with paperwork!
'In organic synthesis, we call decomposition products "crap", however this is not a IUPAC approved nomenclature.' -Nicodem
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Nicodem
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Quote: Originally posted by Zinc  | | I know that acetophenone can be made by pyrolysis of a mixture of Ca acetate and Ca benzoate. Unfortunately my access to chemical literature is
extremely limited so I could not find references to that. |
Saying something like that, after many members here spent lots of time and effort to review the literature on this reaction and post practically all
the relevant papers, is like insulting them. I suggest you to do what you should have done even before opening this thread, to use the search engine
and link all the relevant threads.
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kmno4
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Recenty I have tried something like this.
It was pyrolysis of calcium benzoate under nitrogen - as usually product was brown liquid oil but when I added small crystal of pure benzophenone,
all turn to brown but crstalline mass. It is said that acetophenone is main product (~70%) of pyrolysis of mixture acetate and benzoate of Ca + 400 C
+ nitrogen or argon or CO2. Glass equipment is rater not convenient for such experiments.
There are many papers about this and similar pyrolytical methods, especially on Springer and ScienceDirect databases. Try to do some searching over
there.
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stateofhack
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Sorry to ask, but is there anything wrong with buying it or are you just looking to make it?
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Mush
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Ketonization of Carboxylic Acids by Decarboxylation: Mechanism and Scope
doi.org/10.1002/ejoc.200400546
Abstract
In the ketonic decarboxylation process, a ketone is formed from two moles of carboxylic acid; water and carbon dioxide are produced as
side‐products. At present, the mechanism of this reaction remains under debate; it has been proposed as a radical mechanism, a mechanism involving a
‐keto acid as intermediate, or a concerted mechanism. This paper demonstrates that the latter mechanism is the most likely one and that weak bases
may play the role of promoters. Different processes are reviewed for the syntheses of the following ketones: symmetrical ketones, such as acetone or
3‐pentanone, cyclic ketones, such as cyclopentanone (parent compound and substituted derivatives), fatty ketones, and some unsymmetrical ketones.
Attachment: Renz_2005_ Ketonization of Carboxylic Acids.pdf (154kB)
This file has been downloaded 357 times
Product analysis, reaction mechanism and kinetics of the thermal decomposition of some even chain-length mercury(II) carboxylates
Author links open overlay panelM.SolaAkanni
Hugh D.Burrows1P.BayoBegun
10.1016/0040-6031(84)85109-6
Abstract
The products of the thermal decomposition of some even chain-length mercury(II) carboxylates have been characterized. The products obtained for each
soap include liquid mercury, carbon dioxide, a carboxylic acid, and an odd chain-length alkene. The suggestion that the alkene could be converted to
an odd chain-length carboxylic acid is discussed. The liquid mercury is shown to come directly from the decomposition of the soaps and not through an
intermediate of mercury(II) oxide. A possible mechanism for the degradative route is suggested.
The activation energies for the decomposition of the soaps are independent of the carbon-chain length and correlation between the activation energy
for decomposition and activation energy for viscosity cannot be made as was done for lead(II) carboxylates. However, like lead(II) soaps, the
desorption of carbon dioxide occurs from the surface of the melts.
Binary phase diagrams of some bivalent metal carboxylate systems
Abstract
10.1016/0040-6031(79)85135-7
Binary phase diagrams are presented for mixtures of lead(II), zinc(II), cadmium (II), manganese(II) and mercury(II) octadecanoates. Evidence is
presented to show that addition of one metal carboxylate to another, of the same chain length, does not alter the degree of order of the hydrocarbon
chains either in the solid or liquid phase.
Synthesis and characterisation of polymeric and oligomeric lead(II) carboxylates
Mark R. St J. Foreman,*a M. John Platerb and Janet M. S. Skakleb
10.1039/B103519N
J. Chem. Soc., Dalton Trans., 2001, 1897-1903
Abstract
The hydrothermal reactions of lead(II) acetate with carboxylic acids gave solids of composition [Pb(C4H4O4)] 1 (C4H4O4 = succinate); [Pb6O2(C14H9O3)8]
2 (C14H9O3 = benzoylbenzoate), [Pb(C8H4NO4)2(H2O)] 4 (C8H4NO4 = 2-nitrobenzoate) and [Pb(C8H3N2O6)2(H2O)] 5 (C8H3N2O6 = 3,5-dinitrobenzoate). The
reaction of lead monoxide with trichloroacetic acid in hot wet toluene followed by filtration and cooling gave a solid of composition
[Pb3(C2Cl3O2)6(H2O)3] 3. The compounds were characterised by X-ray single crystal structure determinations. Compounds 1, 3, 4 and 5 are polymeric
whereas 2 is monomeric. The lead co-ordination number ranges from 5 to 8. Compound 2 is a novel hexanuclear lead(II) distorted octahedron containing
two bridging oxide ligands.
Thermal Decomposition of Lead and Copper Acetate
Infrared spectra and thermal decompositions of metal acetates and dicarboxylates'
Canadian Journal of Chemistry, 1968, 46(2): 257-265, 10.1139/v68-040
Abstract
The infrared spectra of rare earth acetates have been studied to examine the metal-acetate bonding. The thermal decomposition of rare earth acetates
as well as lead and copper acetates have been investigated in detail by employing thermogravimetric analysis and differential thermal analysis.
Thermal decomposition of calcium dicarboxylates (malonate to sebacate) have been studied employing t.g.a. and d.t.a. Infrared spectra of the
dicarboxylates have also been studied. Preliminary results on the products of decomposition of dicarboxylates have been reported.
KETONE PRODUCTION FROM THE THERMAL DECOMPOSITION OF CARBOXYLATE SALTS
A Dissertation
by
MICHAEL LANDOLL
p55:
"Analysis of non-expected product yields (Table 3-3) showsthat the majority of expected ketone yield loss occurred because of the production of tars
and heavy oils. The yield of tars and heavy oils increased with the average carboxylate salt molecular weight. It is assumed that the tars and heavy
oils result from ketone degradation, which occurs at the reactortemperature (450–470 °C) [42, 43].Ketone degradation can produce intermediates that
oligomerizeinto longer chain byproducts. Ketone degradation was minimized by rapidly cooling the product as it exited the reactor and by maintaining a
vacuum (~0.4 kPa). Calcium and sodium carbonate that form as the reaction proceeds could form a solid matrix that impedes newly formed ketones from
exitingthe liquid film into the vapor space. This could be especially significant towards the end of the decomposition when the amount of carbonates
are much more than the amount of carboxylate salts, thus allowing forketone degradation.The fact that sodium salts thermally decompose at much higher
temperatures could partially explain why they produce approximately four times as much tars and heavy oils."
https://core.ac.uk/download/pdf/13642758.pdf
There is a great book on ind. manufacture of acetophenone and other compounds.
Handbook on Manufacture of Acetophenone, Alcohols, Alletrhin, Anthracene, Barium Potassium Chromate Pigment, Calcium Cyanamide,
Carboxymethylcellulose, Carotene, Chlorophyll, Chemicals from Acetaldehyde, Fats, Milk, Oranges, Wood, Manufacture of Dye Inter
author: NIIR Board of Consultants & Engineers
Published by Asia Pacific Business Press Inc.
ISBN 10: 8178331780 ISBN 13: 9788178331782
[Edited on 11-10-2019 by Mush]
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