A Stable Homodinuclear Biscobalt(III)–Schiff Base Complex for Catalytic Asymmetric 1,4-Addition Reactions of β-Keto Esters to Alkynones


  • This work was supported by a Grant-in-Aid for Scientific Research (S) (to M.S.), for Scientific Research on Priority Areas (no. 20037010, Chemistry of Concerto Catalysis, to S.M.), and for Encouragements for Young Scientists (A) (to S.M.) from JSPS and MEXT.


Two metal cooperation: A homodinuclear Co2–Schiff base complex Co2(OAc)21 promoted the asymmetric 1,4-addition of β-keto esters to alkynones under solvent-free conditions in air (see scheme). The reactions proceeded without air or moisture sensitivity in high yields and with high enantioselectivities (99–91 % ee) at room temperature under highly concentrated conditions (neat–20 M) with 0.1–2.5 mol % catalyst loading.

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