Ring Expansion of Diazo-Functionalized 4-Hydroxycyclobutenone: Catalytic Ring Opening and Recyclization to 2(5<i>H</i>)-Furanone/Cyclopentenedione and Thermal 4π−8π Electrocyclic Ring Opening−Closure to Diazepinedione
作者:Masatomi Ohno、Masashi Noda、Yoshihiko Yamamoto、Shoji Eguchi
DOI:10.1021/jo980523d
日期:1999.2.1
cyclopentene-1,3-dione via an alpha-carbocation intermediate and a carbenoid (carbene) intermediate, respectively. Thermal rearrangement of some of these compounds led to the formation of diazepinediones without the extrusion of nitrogen through tandem 4pi electrocyclic ring opening and 8pi electrocyclic ring closure processes.
在C-4处带有重氮基团的4-羟基环丁烯酮经酸催化和Rh催化(也光催化)分解,通过α-羰基化中间体和a生成2(5H)-呋喃酮和/或环戊烯-1,3-二酮。类胡萝卜素(卡宾)中间体。其中一些化合物的热重排导致二氮杂二酮的形成而没有通过串联的4pi电动开环和8pi电动闭环过程挤出氮气。