Stereoselective synthesis of functionalized butenolides by the photochemical rearrangement of [2,1]benzisoxazolequinone derivatives
作者:Diego Armesto、Salomé Rodríguez-Morgade、María J. Ortiz、Purificación Vázquez、Tomás Torres
DOI:10.1016/s0040-4020(97)00058-6
日期:1997.3
On direct irradiation 3-alkoxy[2,1]benzisoxazolequinones 1a, 1b, 1c, 1e and 3-N-N-dimethylamino[2,1]benzisoxazolequinone1d undergo rearrangement to the corresponding γ-cyano alkylidenebutenolides 3 in high yield. The reaction is highly stereoselective for compounds 1a, 1b, 1c, and 1d yielding the corresponding Z-butenolides 3 as the only stereoisomer. A mechanism involving triplet nitrene intermediates
在直接辐射下,3-烷氧基[2,1]苯并恶唑啉酮1a,1b,1c,1e和3- N - N-二甲基氨基[2,1]苯并恶唑啉醌1d以高收率重排成相应的γ-氰基亚烷基丁烯内酯3。该反应对于化合物1a,1b,1c和1d具有高度立体选择性,产生相应的Z-丁烯内酯3作为唯一的立体异构体。提出了涉及三线态氮烯中间体的反应机理。