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[摘要]：Enantioselective allylation of aromatic and alpha,beta-unsaturated aldehydes with allyltrichlorosilane catalyzed by two diastereoisomeric (R,R-ax,R)- and (R,S-ax,R)-bis-1,1'-[5,6,7,8-tetrahydro-3-(tetrahydrofuran-2-yl)isoquino line] N,N'-dioxides was studied. The course of the reaction was profoundly influenced by the chosen solvent. The (R, S-ax, R) catalyst efficiently promoted the reaction in THF with enantioselectivity up to 96%. On the other hand, the allylation of aromatic aldehydes in the presence of the (R,R-ax,R) catalyst proceeded only in MeCN (up to 67% ee), and the level of asymmetric induction was strongly influenced by the presence of electron-donating and -accepting groups in the aldehyde. The allylation of a, alpha,beta-unsaturated aldehydes proceeded only in dichloromethane (enantioselectivity up to 68%). |
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