Synthesis and reactivity of 5,6-dibromo-1,2-diformylazulene

Abstract

The reaction of 3,4-dibromothiophene-1,1-dioxide (1) with 3,4-diformyl-6-dimethylaminofulvene (2) gave 5,6-dibromo-1,2-diformylazulene (3) in one step. This reaction is easy and useful for synthesis of 1,2-diformylazulene derivatives. And azulene derivatives were synthesized by using functional groups of (3).