Multicomponent Domino [4+2]/[3+2] Cycloadditions of Nitroheteroaromatics: An Efficient Synthesis of Fused Nitrogenated Polycycles

Abstract

Activation by high pressure allows 3-nitroindole and 3-nitropyrrole derivatives to behave as electron-poor heterodienes in multicomponent domino [4+2]/[3+2] cycloaddition processes. The primary [4+2] inverse demand cycloaddition appears to be completely endo selective, while the subsequent [3+2] process shows a total facial selectivity, setting the stereochemistry at ring junction, and an endo/exo selectivity depending on the nature of the heterocycle. In two operations, a polycyclic diamine featuring a quaternary center at ring junction is efficiently generated.