Diastereodivergent synthesis of chromeno[2,3-]chromenes by tuning all of the reactivity centers of isocyanoacetate.

A novel diastereodivergent tricyclization of isocyanoacetates with -quinone methides was accomplished for the efficient synthesis of chromeno[2,3-]chromene derivatives. All three reactive centers of isocyanoacetate reacted sequentially with two -QMs, affording the products with four adjacent stereocenters in a diastereoselective manner. The asymmetric version was preliminarily investigated.