Asymmetric total synthesis of (-)-alpha-kainic acid using an enantioselective, metal-promoted ene cyclization.

[figure: see text] A short and efficient asymmetric total synthesis of the title compound 1, which is an important neurotransmitter, has been achieved. The synthesis features a metal-promoted, enantioselective ene reaction that provides entry into the kainic acid ring system from very simple precursors. Moreover, the zirconium-mediated Strecker reaction, which represents an outgrowth of earlier amide-to-imine methodology developed in our laboratory, demonstrates remarkable chemoselectivity and stereoselectivity.