Enantioselective synthesis of quaternary α-aminophosphonates by organocatalytic Friedel-Crafts reactions of indoles with cyclic α-ketiminophosphonates

An efficient enantioselective Friedel-Crafts reaction of indoles and cyclic α-ketiminophosphonates was developed using a chiral phosphoric acid (CPA) catalyst. This reaction provides facile access to optically active quaternary α-aminophosphonates in high yields and up to 98% enantioselectivity.