Copper‐Catalyzed Azide–Ynamide Cyclization to Generate α‐Imino Copper Carbenes: Divergent and Enantioselective Access to Polycyclic N‐Heterocycles
作者:Xin Liu、Ze‐Shu Wang、Tong‐Yi Zhai、Chen Luo、Yi‐Ping Zhang、Yang‐Bo Chen、Chao Deng、Rai‐Shung Liu、Long‐Wu Ye
DOI:10.1002/anie.202007206
日期:2020.10.5
Here an efficient copper‐catalyzed cascade cyclization of azide‐ynamides via α‐imino copper carbene intermediates is reported, representing the first generation of α‐imino copper carbenes from alkynes. This protocol enables the practical and divergent synthesis of an array of polycyclic N‐heterocycles in generally good to excellent yields with broad substrate scope and excellent diastereoselectivities
Hf(IV)-Catalyzed Enantioselective Epoxidation of <i>N</i>-Alkenyl Sulfonamides and <i>N</i>-Tosyl Imines
作者:José Luis Olivares-Romero、Zhi Li、Hisashi Yamamoto
DOI:10.1021/ja211880s
日期:2012.3.28
Asymmetric epoxidation of allylic and homoallylic amine derivatives catalyzed by Hf(IV)-bishydroxamic acid complexes is described. Under similar conditions, aldimine and ketimine produced oxaziridines. The sulfonyl group is demonstrated to be an effective directing group for these transformations.