New building blocks, 3,5-dihydro-1H-thieno[3,4-c]pyrrole 2,2-dioxides; preparation and their Diels–Alder reaction with dimethyl acetylenedicarboxylate

Abstract

New building blocks, 3,5-dihydro-1H-thieno[3,4-c]pyrrole 2,2-dioxides 1, have been prepared and react with dimethyl acetylenedicarboxylate to give new types of compound: 7-aza-2,3-dimethylenenorbornene A, the 1:2 adduct B, 1a,3a,6,9-tetrahydrobenz[g]indole C, and dihydroindolosulfolene D depending on the reaction conditions and the N-substituent.