作者:Yu, Heng-Bin、Chen, Yang-Guang、Tian, Yin、Xie, Ming-Sheng、Guo, Hai-Ming
DOI:10.1021/acscatal.4c02072
日期:——
With electronically unbiased styrenes and indenes as dienophiles, a highly enantioselective all-carbon-based inverse-electron-demand Diels–Alder reaction of electron-deficient 2-pyrones is reported. Using C1-symmetric imidazolidine-pyrroloimidazolone pyridine as the tridentate ligand and Ni(OTf)2 as the Lewis acid, diverse bridged bicyclic lactones were obtained in high yields (88–97% yields), diastereoselectivities
以电子无偏苯乙烯和茚作为亲双烯体,报道了缺电子 2-吡喃酮的高度对映选择性全碳基逆电子需求狄尔斯-阿尔德反应。使用C 1 -对称咪唑烷-吡咯并咪唑酮吡啶作为三齿配体和Ni(OTf) 2 作为路易斯酸,高产率地获得了多种桥联双环内酯(88-97%)产率)、非对映选择性(>95:5 dr)和对映选择性(90–99% ee)。环烯胺和2,3-二氢呋喃也是合适的亲二烯体。 DFT 计算支持 Ni(II) 络合物催化反应的协同 [4 + 2] 环加成机制,具有由空间因素引起的高对映选择性。