Double stereodifferentiation in the lewis acid promoted crotylation of (S)-2-Alkoxypropanal with chiral β-Alkyl (E)-Crotylsilanes
作者:Nareshkumar F. Jain、Pier F. Cirillo、Roberta Pelletier、James S. Panek
DOI:10.1016/0040-4039(95)01895-o
日期:1995.11
induction have been evaluated in the Lewis acid promoted addition of (E)crotylsilanes (S)-1 and (R)-2 to (S)-2-alkoxypropanal 3 and 7. These aldehydes are substituted at the α-position with benzyloxy (OBn) to reinforce chelation and tert-butyldiphenylsilyloxy (TBDPSO) groups to prevent chelation with bidentate Lewis acids. The nature of the Lewis acid and the chirality of the silane reagent were found
在路易斯酸促进的(E)-巴豆基硅烷(S)-1和(R)-2加到(S)-2-烷氧基丙醛3和7中,已经评估了1,2-不对称诱导的意义和水平。在α位被苄氧基(OBn)取代以增强螯合,叔丁基二苯基甲硅烷氧基(TBDPSO)基团防止与二齿路易斯酸发生螯合。发现路易斯酸的性质和硅烷试剂的手性在羰基二甲醚面选择性的方向和水平上起着关键作用。