Platinum/Scandium-Cocatalyzed Cascade Cyclization and Ring-Opening Reaction of Tertiary Amines with Substituted Salicylaldehydes to Synthesize 3-(Aminoalkyl)coumarins

The synthesis of 3-(aminoalkyl)coumarins starting with a platinum/scandium-cocatalyzed oxidative dehydrogenation of α,β-C(sp3)−H bonds of tertiary amines in the presence of ambient oxygen followed by reactions with substituted salicylaldehydes is revealed. The in situ formed enamines reacted with various salicylaldehydes, which resulted in the development of a one-pot synthetic protocol involving aldol reaction, cyclization, and then ring-opening.