Preparation method of 2-methyl-3-biphenylmethanol

Abstract

The invention relates to a preparation method of 2-methyl-3-biphenylmethanol. The 2-methyl-3-biphenylmethanol is prepared by carrying out catalyst preparation, a first Grignard reaction, a coupling reaction, and a second Grignard reaction, and carrying out series of steps of filtration, recrystallization, drying and the like. According to the invention, the method which does not adopt tetrahydrofuran as a solvent adopts toluene as the solvent. The method of the invention, which well solves problems of the 2-methyl-3-biphenylmethanol catalyst preparation with toluene as the solvent and adopts pure benzene as a coupling agent, allows no byproducts to be generated.

Description

Technical field [0001] The invention relates to the field of fine chemical synthesis, and specifically relates to a preparation method for a two-step Grignard reaction to synthesize the pesticide intermediate biphenyl alcohol monomer (2-methylbiphenyl-3-methanol). Background technique [0002] Biphenyl alcohol, also known as 2-methyl-3-phenylbenzyl alcohol, is mainly used in the production of the pesticide bifenthrin and as a synthetic raw material for other pharmaceutical products. Biphenyl alcohol is a white crystal with a special smell of alcohol. It is soluble in toluene, methanol, ethyl acetate, acetone and other organic solvents, and insoluble in water. The current synthesis method mainly uses 2,6-dichlorotoluene as raw material. Using tetrahydrofuran as the solvent, through a two-step Grignard reaction, use dimethylformamide to react to generate 2-methyl-3-phenylbenzaldehyde, and then use potassium borohydride to reduce it to the product; or use "Patent No. ZL20071013...

AI Technical Summary

Problems solved by technology

Biphenyl alcohol is a white crystal with a special smell of alcohol, soluble in toluene, methanol, ethyl acetate, acetone and other organic solvents, insoluble in water; the current synthesis method mainly contains 2,6-dichlorotoluene as raw material, Using tetrahydrofuran as a solvent, through a two-step Grignard reaction, react with dimethylformamide to generate 2-methyl-3-phenylbenzaldehyde, and then reduce it to the product with potassium borohydride; or use "patent number ZL200710130941. 7 The patent name is: 2-Methyl-3-phenylbenzyl alcohol clean production process" to produce biphenyl alcohol. Both of the above two methods use tetrahydrofuran as the solvent for the Grignard reaction. Tetrahydrofuran solvent generally contains about 5-15% of water, and it is difficult to remove water by general rectification methods, so the tetrahydrofuran recovered by the above method can only be used for other purposes, and cannot be returned to the system for reuse