Dibromoisobenzofuran as a formal equivalent of didehydroisobenzofuran: reactive platform for expeditious assembly of polycycles.

Two-directional annulation of dibromoisobenzofuran, a formal equivalent to didehydroisobenzofuran, was developed. Importantly, selective bromine-lithium exchange allows the tandem generation of benzynes and dual cycloadditions with two different arynophiles. Also described is the application to the synthesis of a substituted pentacene.