Wang Ming-Zhong, Wong Man-Kin, Che Chi-Ming
Department of Chemistry and Open Laboratory of Chemical Biology of the Institute of Molecular Technology for Drug Discovery and Synthesis, The University of Hong Kong, Pokfulam Road, Hong Kong, China.
Chemistry. 2008;14(27):8353-64. doi: 10.1002/chem.200800040.
An efficient method for intermolecular hydroarylation of aryl and aliphatic alkenes with indoles using a combination of [(PR(3))AuCl]/AgOTf as catalyst under thermal and microwave-assisted conditions has been developed. The gold(I)-catalyzed reactions of indoles with aryl alkenes were achieved in toluene at 85 degrees C over a reaction time of 1-3 h with 2 mol% of [(PR(3))AuCl]/AgOTf as catalyst. This method works for a variety of styrenes bearing electron-deficient, electron-rich, and sterically bulky substituents to give the corresponding products in good to high yields (60-95%). Under microwave irradiation, coupling of unactivated aliphatic alkenes with indoles gave the corresponding adducts in up to 90% yield. Selective hydroarylation of terminal C=C bond of conjugated dienes with indoles gave good product yields (62-81%). On the basis of deuterium-labeling experiments, a reaction mechanism involving nucleophilic attack of Au(I)-coordinated alkenes by indoles is proposed.
已开发出一种高效方法，即在热和微波辅助条件下，使用[(PR(3))AuCl]/AgOTf组合作为催化剂，实现吲哚与芳基烯烃和脂肪族烯烃的分子间氢芳基化反应。吲哚与芳基烯烃的金（I）催化反应在甲苯中于85℃下进行，反应时间为1 - 3小时，使用2 mol%的[(PR(3))AuCl]/AgOTf作为催化剂。该方法适用于各种带有缺电子、富电子和空间位阻大的取代基的苯乙烯，能以良好至高产率（60 - 95%）得到相应产物。在微波辐射下，未活化的脂肪族烯烃与吲哚的偶联反应能以高达90%的产率得到相应加合物。共轭二烯的末端C = C键与吲哚的选择性氢芳基化反应能得到良好的产物产率（62 - 81%）。基于氘标记实验，提出了一种反应机理，即吲哚对金（I）配位的烯烃进行亲核进攻。
