Efficient synthesis of spiro diheterocycles via multi-component dicyclization reaction

Abstract

A facile synthetic protocol for the preparation of spiro diheterocycles from easily available 2′-aminoacetophenones, isocyanates and 1,4-benzoquinones or quinone monoimines under mild conditions has been developed. This multi-component transformation is characterized by efficient construction of two heterocycles and one valuable quaternary carbon in one pot via an in situ cyclization–respiroannulation strategy. Moreover, this reaction showed a broad substrate scope, and generated diverse five-membered oxaspiros.