Method for synthesizing benzoic acid compound from benzyl alcohol compound by ultrasonic-assisted oxidation

Abstract

The invention belongs to the field of synthesis of organic intermediates, and specifically discloses an ultrasonic-assisted synthesis method for a benzoic acid compound. The method comprises the following step: promoting air oxidation of benzyl alcohol by using diethylene glycol dimethyl ether under an ultrasonic-assisted action so as to obtain the benzoic acid compound, wherein a benzyl alcohol raw material is benzyl alcohol, or a benzoic acid derivative containing one to five substituents at different positions on the benzene ring of benzyl alcohol; and a reaction accelerator is the diethylene glycol dimethyl ether. The method provided by the invention has the advantages of easily-available raw materials, simple and convenient reaction conditions, short reaction time, greenness, energy conservation, high reaction selectivity and yield, excellent compatibility of substrate functional groups, and high application value.

Description

technical field [0001] The invention belongs to the technical field of organic intermediate synthesis, and in particular relates to a synthesis method of benzoic acid compounds. Background technique [0002] Benzoic acid is widely used in food, medicine, dyestuff and other chemical fields, and it is also an important class of organic synthesis intermediates. At present, a large number of literatures have reported the synthesis methods of benzoic acid, including: toluene liquid phase oxidation, benzonitrile hydrolysis, toluene chlorination hydrolysis, phthalic anhydride hydrolysis, alcohol oxidation and so on. [0003] Liquid-phase oxidation of toluene is currently the most important method for producing benzoic acid, which is usually produced by catalytic air oxidation of toluene with catalysts such as cobalt and manganese. However, this type of reaction has a low single conversion rate and requires multiple cycles of oxidation reactions. Functional group tolerance is limit...

AI Technical Summary

Problems solved by technology

[0016] (1) The three routes all use a large amount of strong base as a reaction accelerator. After the reaction, an excessive amount of protic acid needs to be added for acid-base neutralization treatment, which is incompatible with alkaline-sensitive functional groups, such as ester groups, cyano groups, etc.;

[0017] (2) Routes 1 and 3 need to use a large amount of organic solvents, which will cause adverse effects on the environment when increasing the reaction cost;

[0018] (3) Routes 2 and 3 require the use of noble metal catalysts and ligands, the reaction cost is high, and the problem of metal residues may occur in the synthesis of pharmaceutical intermediates

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