Didehydroisobenzofuran: A New Reactive Intermediate for Construction of Isoacenofuran

Abstract

An efficient generation method of didehydroisobenzofuran, a new heteroaryne species, was developed by bromine/lithium exchange of the dibromoisobenzofuran. The reactive intermediate, thus generated, was trapped by appropriate arynophile to give the [2+2], [2+3], and [2+4] cycloadducts, respectively. Moreover, the reaction could be applied to the syntheses of isoanthracenofurans (anthra[2,3-c]furans), a new class of heteroacenes, with isoelectoronic structure to the corresponding acenoheteroles (anthra[2,3-b]furans).

Keywords: conjugated molecules; didehydroisobenzofuranes; isoacenofuranes; polycycles; reactive intermediates.