Organocatalytic Dearomative [4 + 2] Cycloadditions of Biomass-Derived 2,5-Dimethylfuran with ortho-Quinone Methides: Access to Multisubstituted Chromanes.

The organocatalytic dearomative [4 + 2] cycloadditions of biomass-derived 2,5-dimethylfuran with ortho-quinone methides were developed, affording two diffferent types of multisubstituted chromanes in high yields and excellent diastereoselectivities. The controllable synthesis of these two types of multisubstituted chromanes could be achieved by succinctly varying the reaction conditions.