Process for the preparation of adapalene

摘要

A process for the preparation of a compound of formula (I), or a salt thereof wherein R is H, C₁-C₈ alkyl, aryl or aryl-C₁-C₈ alkyl; comprising the reaction between a compound of formula (II) wherein R₁ and R₂ are independently hydrogen, C₁-C₈ alkyl, aryl, aryl-C₁-C₈ alkyl, or R₁ and R₂, taken together, form a -(CH₂)_m-V-(CH₂)_n- group, in which V is NR₃ or C(R₃)₂ wherein R₃ is hydrogen, C₁-C₈ alkyl, aryl or aryl-C₁-C₈ alkyl; and m and n, which can be the same or different, are 1 or 2; with a compound of formula (III) in which R₄ and R₅ are independently C₁-C₈ alkyl, aryl or aryl-C₁-C₈ alkyl; in the presence of a Ni (II) salt, an organic ligand and a basic agent, to obtain a compound of formula (I) wherein R is C₁-C₈ alkyl, aryl or aryl-C₁-C₈ alkyl and, if desired, its conversion to a compound of formula (I) wherein R is hydrogen or to a salt thereof.