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.
Silver-Catalyzed Stereoselective [3+2] Cycloadditions of Cyclopropyl-Indanimines with Carbonyl Compounds
作者:Hsiao-Hua Hung、Yi-Ching Liao、Rai-Shung Liu
DOI:10.1002/adsc.201300090
日期:2013.5.17
Silver‐catalyzed stereoselective [3+2] cycloadditions between mono‐substituted cyclopropyl‐indanimines and aldehydes are reported. The stereochemical course of the reaction is rationalized with a cyclic transition state. The resulting indanimine cycloadducts are not readily hydrolyzed unless external aldehydes are present with the silver catalyst. Notably, this hydrolysis process leads to a change
Gold-Catalyzed Cyclization/Oxidative [3+2] Cycloadditions of 1,5-Enynes with Nitrosobenzenes without Additional Oxidants
作者:Chun-Hao Chen、Yen-Ching Tsai、Rai-Shung Liu
DOI:10.1002/anie.201209850
日期:2013.4.22
Golden control: The title reaction (see scheme) proceeds with high stereocontrol to generate the heterocyclic products in good yield. Experiments to probe the mechanism were performed.