Relative Reactivities of Carbonyl and Thiocarbonyl Groups toward Dimethoxycarbene: Two New Dimethoxythiiranes
作者:Małgorzata Dawid、Grzegorz Mloston、John Warkentin
DOI:10.1002/1521-3765(20020503)8:9<2184::aid-chem2184>3.0.co;2-2
日期:2002.5.3
preferentially at the carbonyl group, rather than the thiocarbonyl group of the four-membered ring. However, the minor product reacted with DMC at the thiocarbonyl group to afford a dimethoxythiirane. A product from a corresponding reaction at the carbonyl group could not be found. A rationale for the apparent reversal of relative reactivities of the carbonyl and thiocarbonyl groups is offered, with supporting
由2,5-二氢-1,3,4-恶二唑与2,2,4,4-四甲基-3-硫代氧代环丁酮热解而生成的二甲氧基卡宾(DMC)反应,主要得到2,2-二甲氧基-3, 3,5,5-四甲基-4-硫代氧杂环戊酮可通过整体插入C-CO键而扩环。从整体插入C-CS键起的4,4-二甲氧基-2,2,5,5-四甲基-3-硫代氧杂环戊酮是次要产物。因此,卡宾优先在羰基而非四元环的硫代羰基上反应。但是,次要产物在硫羰基上与DMC反应,得到二甲氧基硫代硅烷。找不到相应的羰基反应产物。提供了明显逆转羰基和硫代羰基的相对反应性的理由,并提供了支持证据。