Stereoretentive O-to-C rearrangement of vinyl acetals: solvent cage effects as a stereocontrol element.
Stereoretentive O-to-C rearrangement of vinyl acetals: solvent cage effects as a stereocontrol element.
复制标题
乙烯基缩醛的立体保留O-C重排：作为立体控制元素的溶剂笼效应。
DOI：
10.1021/ja026972j
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发表时间：
2002
影响因子：
15
通讯作者：
Rovis,Tomislav
中科院分区：
文献类型：
--
作者：
Zhang,Yongda;Reynolds,NathanT;Manju,Kavita;Rovis,Tomislav
Me3Al和BF3·oet2协同作用可诱导Lewis酸介导的手性乙烯缩醛重排，产生立体保持产物。在该反应中获得的选择性（86:14至96:4）与依靠氧羰基面偏控制新形成的立体中心时观察到的选择性是互补的。有证据表明，该反应是通过溶剂笼中离子对的紧密结合而发生的。通过离子中间体将C−O键的立体化学转化为C−C键的立体中心，是对类似的已建立的方法（如Claisen重排）的补充。
The Lewis acid-mediated rearrangement of chiral vinyl acetals may be induced to provide the product of stereoretention using Me3Al and BF3·OEt2in concert. The selectivities obtained in this reaction (86:14 to 96:4) are complementary to that observed when relying on oxocarbenium facial bias to control the newly formed stereocenter. Evidence is presented that this reaction occurs by tight ion-pair binding in the solvent cage. The relay of C−O bond stereochemistry to a C−C bond stereocenter via ionic intermediates is an addition to similar established methods such as the Claisen rearrangement.