Second generation catalytic asymmetric synthesis of tamiflu: Allylic substitution route

Catalytic asymmetric synthesis of Tamiflu, an important antiinfluenza drug, was achieved. After the catalytic enantioselective desymmetrization of meso-aziridine 3 with TMSN3, using a Y catalyst (1 mol %) derived from ligand 2, an allylic oxygen function and C1 unit on the CC double bond were introduced through cyanophosphorylation of enone and allylic substitution with an oxygen nucleophile. This second generation route of Tamiflu is more practical than our previously reported route.