Gold-Catalyzed Oxidative Cyclization of 1,5-Enynes Using External Oxidants
作者:Dhananjayan Vasu、Hsiao-Hua Hung、Sabyasachi Bhunia、Sagar Ashok Gawade、Arindam Das、Rai-Shung Liu
DOI:10.1002/anie.201102581
日期:2011.7.18
Golden circle: Two gold‐catalyzed oxidativecyclizations of 1,5‐enynes using 8‐methylquinoline N‐oxide are presented (see example). Experimental results indicate that both reactions proceed through prior oxidation of alkyne to form α‐carbonyl intermediates and subsequent intramolecular carbocyclization.
Generation of Donor/Donor Copper Carbenes through Copper-Catalyzed Diyne Cyclization: Enantioselective and Divergent Synthesis of Chiral Polycyclic Pyrroles
作者:Feng-Lin Hong、Ze-Shu Wang、Dong-Dong Wei、Tong-Yi Zhai、Guo-Cheng Deng、Xin Lu、Rai-Shung Liu、Long-Wu Ye
DOI:10.1021/jacs.9b09303
日期:2019.10.23
yields with wide substratescope and excellent enantioselectivities (up to 97:3 e.r.). Importantly, this protocol represents the first copper-catalyzed asymmetric diyne cyclization. Moreover, mechanisticstudies revealed that the generation of donor/donor copper carbenes is presumably involved in this 1,5-diyne cyclization, which is distinctively different from the related gold catalysis, and thus it constitutes