Chiral Calcium Phosphate-Catalyzed Enantioselective Amination of 3-Aryl-2-oxindoles with Dibenzyl Azodicarboxylate.

A chiral calcium phosphate-catalyzed enantioselective amination of 2-oxindoles with dibenzyl azodicarboxylate has been developed, affording the products in consistently high yields and excellent enantioselectivity. This synthetic method features low catalyst loading and a high catalytic efficiency. Moreover, the practical value of this process is well demonstrated by a scale-up experiment and a trial of catalyst recovery and reuse.