Dioxopyrrolines. XLV. (2+2)Photocycloaddition of 4-ethoxycarbonyl-5-aryl-1H-pyrrole-2,3-dione to cyclopentene derivatives: Formation of dihydropyridones.
作者:Takehiro SANO、Yoshie HORIGUCHI、Kazue IMAFUKU、Yoshisuke TSUDA
DOI:10.1248/cpb.38.366
日期:——
Photocycloaddition reactions of 4-ethoxycarbonyl-5-aryl-1H-pyrrole-2, 3-dione (1) with cyclopentadiene, indene, and cyclopentene gave the dihydropyridones 8, 11, and 12 as major products, respectively. Formation of them can be rationalized by assuming the formation of a 2s + 2a adduct predicted by the stereoselection rule and subsequent skeletal rearrangement. The stereochemical results seem to support the hypothesis that the donor-acceptor interaction as theoretically deduced by Epiotis plays an important role in determining the stereochemical pathway of photocycloaddition.
4-乙氧羰基-5-芳基-1H-吡咯-2,3-二酮(1)与环戊二烯、茚和环戊烯的光环加成反应分别主要生成二氢吡啶酮8、11和12。它们的形成可以通过假设形成由立体选择规则预测的2s + 2a加合物并随后发生骨架重排来合理化。立体化学结果似乎支持了Epistis从理论上推导的供体-受体相互作用在决定光环加成的立体化学途径中起重要作用这一假设。