The decarboxylative coupling of diversely substituted benzoic acids with internal alkynes proceeds smoothly in the presence of a [RhCl(cod)]2/1,2,3,4-tetraphenyl-1,3-cyclopentadiene catalyst system to selectively produce highly substituted naphthalene derivatives. The catalyst system is applicable to constructing anthracene and benzo[c]thiophene frameworks through reactions of naphthoic and thiophene-2-carboxylic acids, respectively.
Key words
C–H functionalization - carboxylic acids - decarboxylative coupling - homologation - rhodium catalysis