En Route to an Efficient Catalytic Asymmetric Synthesis of AS-3201

A catalytic asymmetric synthesis of AS-3201 via catalytic asymmetric amination with a novel lanthanum−amide complex is described. The amination reaction proceeded efficiently with as little as 1 mol % of catalyst loading, allowing for an efficient access to the key intermediate for the synthesis of AS-3201, a potent aldose reductase inhibitor.