Effect of Spiro Ring Size on the Photochemical Ring Expansion of Dispiro Substituted Cyclobutane-1,3-diones
作者:Koji Kimura、Masakazu Takamura、Shigeru Koshibe、Masayoshi Juro、Yoshihiro Fukuda、Yoshinobu Odaira
DOI:10.1246/bcsj.49.741
日期:1976.3
The photochemical ring expansion of dispiro substituted cyclobutane-1,3-diones in methanol has been investigated. The formation of ring expansion product was strongly dependent on the spiro ring size of dispiro substituent. The ring expanded acetal was obtained in a low yield when the spiro ring of dispiro substituted cyclobutane-1,3-diones was a five- or seven-membered ring. This is the first example
研究了二螺取代的环丁烷-1,3-二酮在甲醇中的光化学扩环。扩环产物的形成强烈依赖于二螺取代基的螺环尺寸。当双螺取代的环丁烷-1,3-二酮的螺环为五元环或七元环时,扩环缩醛的收率较低。这是环丁烷-1,3-二酮光化学扩环的第一个例子。假设了一种机制。