Synthesis, metallation and nucleophilic reactivity of 2,6-bis(trialkylsilyl)-<i>4H</i>-thiopyrans
作者:Tiziano Nocentini、Jean-Philippe Bouillon、Antonella Capperucci、Charles Portella
DOI:10.1080/17415993.2013.789517
日期:2013.12.1
-4H-thiopyran. Its lithium salt exhibited also interesting properties: Peterson olefination products were formed under reaction with aldehyde, and a stable thiabenzene was effectively obtained with n-hexylbromide. The role of the silyl substituents was decisive to explain the particular aspects of the reactivity of these silyl substituted thiopyrans. GRAPHICAL ABSTRACT
我们在本文中报告了 (i) 通过 1,5-双(酰基硅烷) 硫化-环化合成 2,6-双(三烷基甲硅烷基)-4H-噻喃和 (ii) 这些噻喃的锂化以及它们的锂盐与各种亲电试剂。大多数反应导致 4 位和 2 位碳的烷基化,前者通常更具区域选择性。在正己基溴的情况下发生在硫原子上的部分反应。有效且完全区域选择性的三甲基甲硅烷基化产生了 2,4,6-三(三烷基甲硅烷基)-4H-噻喃。它的锂盐也表现出有趣的特性:与醛反应形成彼得森烯化产物,与正己基溴有效地获得稳定的噻苯。甲硅烷基取代基的作用对于解释这些甲硅烷基取代的噻喃的反应性的特定方面是决定性的。