Investigation of the catalуtic activitу of K2CO3 in the carboxуlation reaction of phenol with sodium ethуl carbonate

The catalуtic activitу of К2СО3 in the carboxуlation reaction of phenol with sodium ethуl carbonate has been investigated. The aim of the research was to develop a new efficient method for producing salicylic acid which is widely used in pharmaceuticals and other type preparations, also used in agriculture as an effective plant growth promoter. The most widespread synthesis method of salicylic acid is the Kolbe-Schmitt of phenol carboxylation, but it has a number of serious disadvantages. One of the alternative methods is the use of alkali metal salts of mono ethers of the carbonic acids as carboxylating agents in the carboxylation of phenol. In order to improve the method of production of salicylic acid, the catalytic activity of the К2СО3 catalyst at the carboxylation of phenol with sodium ethyl carbonate was studied for the first time. The effect of the process parameters (temperature, pressure, reaction time, ratio of catalyst to carboxylating agent) on the yield of the target product was studied. It was found optimal conditions: T=160°C, PCO2=10 atm, τ=7(4+3) h, [К2СО3]:[SEC]=0.07:1 at which the yield of the target product was 80%. The yields of the target product at phenol carboxylation with sodium ethyl carbonate in the presence and without K2CO3 were determined. It was found that К2СО3 shows the catalytic activity during carboxylation reaction.

Carboxylation of phenol and its derivatives with sodium ethyl carbonate

A comparison activity of phenol and its derivatives in carboxylation reaction with sodium ethyl carbonate was carried out (the ratio between substrate and sodium ethyl carbonate was 2:1, T=185°С, Pco

Carboxylation of hydroxyarens with metal alkyl carbonates

The objective of this work was to investigate the possibility of using alkali metal salts of ethylcarbonic acid as a carboxylating reagent in phenol (naphthols) carboxylation and developing a new and simple method for the synthesis of hydroxybenzoic and hydroxynaphthoic acids having broad practical application. It was found that sodium ethyl carbonate and potassium ethyl carbonate can be successfully used as carboxylating agents in carboxylation of phenol and naphthols. For the first time, the effects of the gaseous medium (air, carbon dioxide, argon), pressure, temperature and reaction time on the proceedings of the carboxylation reactions were examined. Simple and convenient procedures for the syntheses of o- and p-hydroxybenzoic, p-aminosalicylic, 1-hydroxy-2-naphthoic, 1-hydroxy-4-naphthoic and 2-hydroxy-3-naphthoic acids were developed. New efficient technologies for preparation of drugs salicylic acid (antiseptic activity), p-aminosalicylic acid (antituberculous activity) and p-hydroxybenzoic acid (bactericide activity) based on carboxylation reactions of phenol and m-aminophenol with sodium and potassium salts of ethyl carbonic acid were worked out.