Cyanobenzene-boronic acid or ester preparation in high yield comprises treating halo-benzonitrile and trialkyl borate with alkyl lithium, used as intermediate e.g. for liquid crystals, pesticides or drugs

摘要

Preparation of cyanobenzene-boronic acids and esters (I) involves treating a mixture of a halo-benzonitrile (II) and a trialkyl borate (III) with an alkyl lithium (IV) and optionally hydrolyzing the obtained boronic acid ester. Preparation of cyanobenzene-boronic acids and esters of formula (I) involves treating a mixture of a halo-benzonitrile of formula (II) and a trialkyl borate of formula B(OA)3 (III) with an alkyl lithium of formula A-Li (IV) and optionally hydrolyzing the obtained boronic acid ester. R = H or A; R1, R2 = H, A, OA, F, Cl or phenyl (optionally substituted by 1 or 2 of A, OA, F and Cl); A = 1-6C alkyl; L = Br or I.