Poly[(S)-3-vinyl-2,2'-dihydroxy-1,1'-binaphthyl](L*)was obtained by taking off the protecting groups of poly[(S)-3-vinyl-2,2'-bis(methoxymethoxy)-1,1'-binaphthyl](poly-1).L*was proved to keep a stable ...Poly[(S)-3-vinyl-2,2'-dihydroxy-1,1'-binaphthyl](L*)was obtained by taking off the protecting groups of poly[(S)-3-vinyl-2,2'-bis(methoxymethoxy)-1,1'-binaphthyl](poly-1).L*was proved to keep a stable helical con-formation in solution.The application of helical L*in the asymmetric addition of diethylzinc to aldehydes has been studied.The catalytic system employing 10 mol%of L*and 150 mol%of Ti(OiPr)_(4) was found to promote the addi-tion of diethylzinc to a wide range of aromatic aldehydes,giving up to 99%enantiomeric excess(ee)and up to 93%yield of the corresponding secondary alcohol at 0℃.The chiral polymer can be easily recovered and reused with-out loss of catalytic activity as well as enantioselectivity.展开更多
基金National Natural Science Foundation of China(No.21172186)Doctor Student Research Foundation of Chinese Education Ministry(No.20134301110004)for financial support of this work.
文摘Poly[(S)-3-vinyl-2,2'-dihydroxy-1,1'-binaphthyl](L*)was obtained by taking off the protecting groups of poly[(S)-3-vinyl-2,2'-bis(methoxymethoxy)-1,1'-binaphthyl](poly-1).L*was proved to keep a stable helical con-formation in solution.The application of helical L*in the asymmetric addition of diethylzinc to aldehydes has been studied.The catalytic system employing 10 mol%of L*and 150 mol%of Ti(OiPr)_(4) was found to promote the addi-tion of diethylzinc to a wide range of aromatic aldehydes,giving up to 99%enantiomeric excess(ee)and up to 93%yield of the corresponding secondary alcohol at 0℃.The chiral polymer can be easily recovered and reused with-out loss of catalytic activity as well as enantioselectivity.
