Efficient method for the synthesis of hetarenoindanones based on 3-arylhetarenes and their conversion into hetarenoindenes

A series of hetarenoindanones have been prepared by direct double metalation of the appropriate 3-phenylhetarene with butyllithium in the presence of TMEDA followed by treatment of the resulting dilithium compound with ethyl NiV-dimethylcarbamate. All hetarenoindanones were reduced according to Wolff-Kishner by hydrazine in the presence of KOH to the corresponding hetarenoindenes.