López Carlos Silva, Alvarez Rosana, Vaz Belén, Faza Olalla Nieto, de Lera Angel R
Departamento de Química Orgánica, Universidade de Vigo, Lagoas-Marcosende, 36310 Vigo, Galicia, Spain.
J Org Chem. 2005 Apr 29;70(9):3654-9. doi: 10.1021/jo0501339.
[reaction: see text] A comprehensive scan of the transition state space for the reaction of 2-(trimethylsiloxy)furan and methacrolein (24 combinations) offered a satisfactory explanation of the high like diastereoselectivity obtained experimentally in the Mukaiyama vinylogous aldol reaction of these and related partners. It was determined that the syn-gamma-hydroxyalkylbutenolides are formed preferentially following a g(+) orientation of the two reactants with the aldehyde in the s-trans conformation. Diastereoselectivity is shown to be caused by a combination of subtle effects favoring the formation of the like product.
[反应：见正文] 对2-(三甲基硅氧基)呋喃与甲基丙烯醛反应的过渡态空间进行全面扫描（24种组合），为这些反应物及相关反应物在Mukaiyama烯丙型羟醛缩合反应中实验所获得的高非对映选择性提供了令人满意的解释。已确定，顺式-γ-羟烷基丁烯内酯优先在两种反应物呈g(+)取向且醛处于s-反式构象时形成。非对映选择性表明是由有利于形成同类产物的细微效应组合所致。
