Phosphine-Catalyzed Annulations of 4,4-Dicyano-2-Methylenebut-3-enoates with Maleimides and Maleic Anhydride
作者:Xiao-Nan Zhang、Gen-Qiang Chen、Xiang-Ying Tang、Yin Wei、Min Shi
DOI:10.1002/anie.201406100
日期:2014.9.26
A novel phosphine‐catalyzed [4+1] annulation of maleimides with 4,4‐dicyano‐2‐methylenebut‐3‐enoates has been developed to afford spirocyclic products, and the maleimides serves as C1 synthons. Moreover, a phosphine‐catalyzed formal [3+2] annulation between 4,4‐dicyano‐2‐methylenebut‐3‐enoates and maleic anhydride has been also achieved, and maleic anhydride behaved as a C3 synthon in the reaction
已开发出一种新的膦催化的马来酰亚胺与4,4-二氰基-2-亚甲基丁-3-烯酸酯的[4 + 1]环化反应,可提供螺环产物,而马来酰亚胺可作为C 1 合成子。此外,还实现了膦催化的4,4-二氰基-2-亚甲基丁-3-烯酸酯与顺丁烯二酸酐之间的正[3 + 2]环化反应,顺丁烯二酸酐 在反应中可作为C 3合成子。提供官能化的环戊烯酮。稳定的含两性离子化合物是两种圆环中的关键反应中间体,并已成功分离。在控制实验和氘标记实验的基础上提出了合理的机制。