A Double Deprotonation Strategy for Cascade Annulations of Palladium–Trimethylenemethanes and Morita–Baylis–Hillman Carbonates to Construct Bicyclo[3.1.0]hexane Frameworks
作者:Zhen‐Hong Yang、Peng Chen、Zhi‐Chao Chen、Zhi Chen、Wei Du、Ying‐Chun Chen
DOI:10.1002/anie.202102842
日期:2021.6.14
species having an activated alkene moiety through a second deprotonation process, which then undergo cascade [1+2]/[3+2] annulations to furnish complex bicyclic [3.1.0]hexane frameworks having three contiguous quaternary stereogenic centers with good to excellent enantioselectivity. Moreover, by using benzoyl aldehyde-derived substrates, a [1+4]/[3+2] annulation sequence is similarly developed to produce
在这里,我们报告说,在 Morita-Baylis-Hillman 碳酸盐的存在下,可以实现通过去质子化策略对 Tsuji 的 2-(氰甲基)烯丙基碳酸酯进行化学选择性活化以生成钯-三亚甲基甲烷 1,3-偶极子。以下 S N 2'-加成能够通过第二次去质子化过程形成具有活化烯烃部分的新 1,3-偶极物质,然后进行级联 [1+2]/[3+2] 环化以提供复杂的双环[3.1.0] 己烷骨架具有三个连续的四元立体中心,具有良好到出色的对映选择性。此外,通过使用苯甲醛衍生的底物,类似地开发了 [1+4]/[3+2] 环化序列以产生稠合的环戊二烯 [b] 呋喃结构。