Study Of Synthesis Of α-(4-Substituted Phenyl) Isobutyric Acid By 1,2-Aryl Shift Rearrangement Reaction

a-aryl alkyl carboxylic acid is an important organic intermediates, which was widely used in medicine, pesticide and other fields. This paper studied the new synthetic methods of a-aryl alkyl carboxylic acid compounds. A series of substituted benzene, such as Fluorobenzene, Toluene, Anisole, was used as the raw materials. By the procedures of Friedel-crafts acyl reaction, bromination reaction, protection reaction of carbonyl group,1,2-aryl shift Rearrangement reaction, hydrolysis and acidification reaction of esters, a novel synthetic method of a-(4-substituted phenyl) isobutyric acid was finally designed and developed.The better conditions of this novel method were determined by optimization of the whole process, including the temperature, time, concentration of the Friedel-crafts acyl reaction et al; the temperature and concentration of the bromination reaction; the solvent, protector, catalyst, time and concentration of the protection reaction of carbonyl group, the solvent, catalyst and time of the 1,2-aryl shift Rearrangement reaction et al and the solvent, volume ratio and dosage of base of the hydrolysis reaction et al. The target products and intermediates were identified by spectru analysis and structure identification.The novel method that is used to synthesize a-(4-substituted phenyl) isobutyric acid has several advantages, including the cheap raw materials, the less toxic solvents, and the higher yield of products, the simple process flow that is easy to industrial production.