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

(1)将各种有机锂化合物与光学活性2-甲酰基-1，3-氧杂硫烷衍生的亚胺或肼加成，得到高非对映选择性(&gt；99%de)的胺类衍生物。(2)光学活性2-丁烯基-1，3-氧杂硫烷的非对映选择性1，4-加成反应。在YbCl3存在下，有机试剂的加入使1，4-加合物成为单一的非对映化合物。另一方面，在催化量的CuBr存在下，用有机镁试剂处理另一个非对映异构体，得到了具有高非对映选择性的另一个非对映异构体。(3)三氟化镧是各种胺1，4-加成反应的良好催化剂。该反应成功地应用于光学活性β-内酰胺的非对映选择性合成。(4)实现了2-烷基-2-甲酰胺与烷基-二氯化铝的立体选择性烷基化反应。在2-甲基-3-氧代酰胺中加入三烷基铝或烷基氯化锰，得到具有高立体选择性的相应的3-羟基-2-甲基酰胺。

(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.