Development of Highly Stereoselective Reaction in Metal and Hetero-Atom Combined Reaction Filed

点击翻译按钮获取中文摘要

(1) An addition of various organolithium compounds to imine or hydrazine derived from optically active 2-formy1-1,3-oxathiane gave amine derivatives with high diastereoselectivity (>99% de) in good yields.(2) Diastereoselective 1,4-addition reaction of optically active 2-butenoy1-1,3-oxathiane was studied. The addition of organocupper reagent in the presence of YbCl_3 provided 1,4-adduct as a single diastercomeric compound. On the other hand, treatment with organomagnesium reagent in the presence of a catalytic amount of CuBr gave the other diastereomer with high diastereoselectivity.(3) Lanthanoid triflate proved to be a good catalyst for the 1,4-addition reaction of various amines to alpha, beta-unsaturated esters. The reaction was succesfully applied to a diastereoselective synthesis of optically active beta-lactams.(4) Stereoselective alkylation of 2-alky1-2-formylamide with alky1-aluminium dichloride was achieved. An addition of trialkylaluminium or alkylmanganese chloride to 2-methy1-3-oxo-amide gave the corresponding 3-hydroxy-2-methylamide with high stereoselectivity.