ISSN 1070-4272, Russian Journal of Applied Chemistry, 2007, Vol. 80, No. 6, pp. 945!950. + Pleiades Publishing, Ltd., 2007.
Original Russian Text + T.E. Zhesko, V.P. Boyarskii, A.G. Nikitina, 2007, published in Zhurnal Prikladnoi Khimii, 2007, Vol. 80, No. 6,
AND INDUSTRIAL ORGANIC CHEMISTRY
A Versatile Procedure for Synthesis of Organic Acids
by Cobalt Carbonyl Catalyzed Carbonylation
of Organic Halides
T. E. Zhesko, V. P. Boyarskii, and A. G. Nikitina
VNIIINeftekhim Joint-Stock Company, St.Petersburg, Russia
Galar Limited Liability Company, St. Petersburg, Russia
Received November 9, 2006
Abstract-A versatile procedure for synthesis of a broad range of fatty-aromatic and aromatic acids by
carbonylation of the corresponding halides under very mild conditions in the presence of cobalt carbonyl as
a catalyst was suggested. The main principles of a flexible process for production of practically significant
acids and their derivatives were developed.
Aromatic and fatty-aromatic acids and their deriv-
atives (ethers, salts) have a wide application area.
They are used in paint and varnish industry and in
production of pharmaceuticals, plant-protecting agents,
fragrance compounds, lubricants, and corrosion inhib-
itors. In addition, aromatic carboxylic acids find
growing application in production of liquid-crystal
materials. Di- and polyarenecarboxylic acids are used
in production of liquid crystal thermoplastics, nano-
materials, and electroluminescent compounds applied
in development of new kinds of equipment.
The conventional synthesis of these acids is based
on classical organic reactions: alkylation, acylation,
oxidation, and cyanation and has serous disadvantages.
The methods are multistage, low-selective, expensive,
and environmentally hazardous.
An alternative method is carbonylation of organic
halides, which finds growing application for synthesis
of fatty-aromatic and aromatic acids . For example,
phenylacetic acid (FAA) can be readily prepared by
carbonylation of benzyl chloride under very mild
conditions (135 atm, 40380oC) in the presence of
the conventional catalyst for oxo synthesis, cobalt car-
bonyl. The reaction is performed in an alkaline-alco-
holic (mainly in methanol) solution, in which the cat-
alyst exists in the salt form MCo(CO)
. Since benzyl
chloride readily enters into nucleophilic substitutions,
it is activated in the course of carbonylation owing to
the substitution of chlorine by the Co(CO)
form alkylcobalt carbonyl (1). Then the CO molecule
is inserted to form acylcobalt carbonyl complexes (2).
The target methyl phenylacetate (3) is reductively
eliminated under the action of the methylate anion :
Cl 776 PhCH
The optimization of PAA synthesis allowed us to
obtain this compound in a yield of no less than 95%
. We also developed a procedure for preparing
the cobalt catalyst in the form of Co(CO)
anol under relatively mild conditions (at pressures of
up to 50 atm) . This procedure can be used instead
of the reaction of benzyl chloride with highly toxic so-
dium cyanide. A batch of PAA (~40 kg) was prepared
by this method for the first time in Russia and was
tested in production of antibiotics. Naphthylacetic acid
was prepared similarly. This compound is an inter-
mediate product in production of Naphthizin pharma-
ceutical, Heteroauxin plant growth stimulant, and
a valuable monomer, phenylenediacetic acid (Table 1).
Methyl monochloroacetate enters into this reaction
at a higher CO pressure (up to 10 atm) to form malon-
ic acid. Practically significant fatty-aromatic and