(NHC)NiH-Catalyzed Intermolecular Regio- and Diastereoselective Cross-Hydroalkenylation of Endocyclic Dienes with α-Olefins
作者:Xiaoyan Lian、Weihao Chen、Liang Dang、Yuchen Li、Chun-Yu Ho
DOI:10.1002/anie.201703706
日期:2017.7.24
3‐product selectivity (i.e., with the H atom at C4 and the alkenyl group at C3 of the diene) was observed, which is different from the selectivity of known dimerizations of α‐olefins with both acyclic Co and Fe systems. The influence of the various substituents on the NHC, 1,3‐diene, and α‐olefin on the chemo‐, regio‐, and diastereoselectivity was studied. High levels of chirality transfer were observed
使用一组中性(NHC)Ni II H(OTf)催化剂和阳离子Ni II,可以在最少被α-烯烃取代的位置上实现内环1,3-二烯的高选择性交叉氢化烯基化具有新型NHC配体的催化剂。在杂原子辅助下,通常以等量的两种底物和2-5 mol%的催化剂负载量获得高收率的跳过的二烯。观察到稀有的4,3-产物选择性(即,H原子位于二烯的C4和烯基在C3上),这与已知的α-烯烃在无环Co和Fe系统中的二聚反应的选择性不同。研究了各种取代基对NHC,1,3-二烯和α-烯烃的化学,区域和非对映选择性的影响。用手性环己二烯衍生物观察到高水平的手性转移。