Stereo- and regiocontrol of acyclic systems via the lewis acid mediated reaction of allylic stannanes with aldehydes
作者:Yoshinori Yamamoto、Hidetaka Yatagai、Yuji Ishihara、Norihiko Maeda、Kazuhiro Maruyama
DOI:10.1016/0040-4020(84)80007-1
日期:1984.1
The reaction of crotyltrialkylstannanes (1) with aldehydes in the presence of BF3,OEt2, produces the corresponding erythro homoallyl alcohols (2) predominantly regardless of the geometry of the double bond. Further, the Lewis acid mediated reaction exhibits the enhanced Cram selectivity in comparison with other allylic organometallic reactions which proceed in the absence of Lewis acids. Use of AlCl3-i-PrOH
在BF 3,OEt 2存在下,巴豆基三烷基锡烷(1)与醛的反应主要产生相应的赤型均烯丙基醇(2),而与双键的几何形状无关。此外,与在不存在路易斯酸的情况下进行的其他烯丙基有机金属反应相比,路易斯酸介导的反应显示出提高的Cram选择性。使用AlCl 3 -i-PrOH作为路易斯酸完全改变了反应过程;产生线性加合物(12)而不是支链加合物(13)。1-BF 3,OEt 2的反应该系统被用于(±)Prelog-Djerassi乳酸(16)和(-)芦竹内酯(19)的短时和立体选择性合成。