Palladium-catalyzedasymmetricallylicalkylation of 1,3-diphenyl-2-propenyl acetate (4) with a dimethyl malonate-BSA-LiOAc system has been successfully carried out in the presence of a new chiral prolinol-derived aminophosphine ligand (3e) in good yield with good enantioselectivity (up to 96% ee).
Development of Chiral (<i>S</i>)-Prolinol-Derived Ligands for Palladium-Catalyzed Asymmetric Allylic Alkylation: Effect of a Siloxymethyl Group on the Pyrrolidine Backbone
A series of novel chiral aminophosphine ligands are designed and readily prepared from (S)-prolinol. The reactivity and selectivity in the palladium-catalyzedasymmetricallylicalkylation of 1,3-diphenyl-2-propenyl acetate with a dimethyl malonate−BSA−LiOAc system using these chiral ligands are evaluated, and the structural elucidation of ligands and palladium complex is also conducted. Moreover,
Formation of Cyclic Phosphonium Salts in Trichlorosilane Reduction of Phosphine Oxides Bearing a Pendant Hydroxyl Group and Their Hydrolysis to Cyclic Phosphine Oxides
作者:Zuo-Gang Huang、Biao Jiang、Ke-Jun Cheng
DOI:10.1080/10426500701280137
日期:2007.6.1
An unusual ring closure to cyclicphosphoniumsalts was observed during trichlorosilane reduction of phosphine oxides with a pendant hydroxylmethyl group. Alkaline hydrolysis of the cyclicphosphoniumsalts afforded a cyclic phosphine oxide and a ring-fission product.