Cyclopropanespiro-β-lactones derived from 4-[(Z)-ethylidene]-3-methyloxetan-2-one: diastereoselective formation and rearrangement reactions
作者:Niall W.A. Geraghty、Patrick McArdle、Laverne M.A. Mullen
DOI:10.1016/j.tet.2011.03.013
日期:2011.5
formation of cyclopropanespiro-β-lactones. In contrast to most alkene cyclopropanations, including those involving diketene, the reaction occurs diastereoselectively. A computational model of the reaction has been developed that accounts for the observed stereochemistry. The metal promoted thermal rearrangement of these spiro compounds is also unusual in that it affords pyranones, rather than the decarboxylation
单取代的重氮酯和酮与4-[(Z)-亚乙基] -3-甲基氧杂环丁烷-2-酮的金属催化反应导致形成环丙烷螺-β-内酯。与大多数烯烃环丙烷化反应(包括涉及双烯酮的反应)相反,该反应是非对映选择性的。已经开发了解释所观察到的立体化学的反应的计算模型。这些螺环化合物的金属促进的热重排也是不同寻常的,因为它提供吡喃酮,而不是通常提供β-内酯的脱羧产物,或由双烯酮衍生的环丙烷螺-β-内酯形成的呋喃酮。