Eco-friendly α,β-C(sp 3 )-H difunctionalization of tertiary amines via sequential [1,5]-hydride transfer and hetero-Diels-Alder cyclization.

An unprecedented eco-friendly multi-component domino reaction for the synthesis of novel N , O -acetals is reported. The protocol involves sequential coupling, [1,5]-hydride transfer and hetero-Diels-Alder cyclization. This new strategy enables direct α,β-difunctionalization of cyclic amines utilizing enamines generated in situ . The methodology features high atom and step economy, excellent regioselectivity, a simple work-up procedure and molecular diversity.