3265-14-3Relevant articles and documents
Rh2(OAc)4-catalyzed regioselective intermolecular C-H insertion reactions: Novel synthesis of 2-pyrrol-3′-yloxindoles
Muthusamy, Sengodagounder,Gunanathan, Chidambaram
, p. 1783 - 1786 (2002)
Regioselective synthesis of 2-pyrrol-3′-yloxindoles has been achieved by the reactions of cyclic diazo carbonyl compounds la-e with pyrrole and substituted pyrroles (2a-d) in the presence of rhodium(II) acetate catalyst via intermolecular C-H insertion reaction.
Visible-Light-Mediated Cyclopropanation Reactions of 3-Diazooxindoles with Arenes
Zhao, Shuai,Chen, Xiang-Xiang,Gao, Nan,Qian, Mingcheng,Chen, Xin
, p. 7131 - 7140 (2021)
The cyclopropanation reaction of 3-diazooxindoles with arenes was first accomplished using visible-light irradiation. A series of spiro[norcaradiene-7,3′-indolin]-2′-ones were synthesized for the first time in high yields and with excellent diastereoselectivities. The synthetic usefulness of this catalyst-free photochemical methodology is illustrated by the further controllable rearrangement and epoxidation reactions.
Copper-Catalyzed Oxidation of Hydrazones to Diazo Compounds Using Oxygen as the Terminal Oxidant
Liu, Wenbin,Twilton, Jack,Wei, Bo,Lee, Maizie,Hopkins, Melissa N.,Bacsa, John,Stahl, Shannon S.,Davies, Huw M. L.
, p. 2676 - 2683 (2021/03/03)
A mild method for accessing diazo compounds via aerobic oxidation of hydrazones is described. This catalytic transformation employs a Cu(OAc)2/pyridine catalyst and molecular oxygen from ambient air as the terminal oxidant, generating water as the sole byproduct and affording the desired diazo compounds within minutes at room temperature. A broad array of electronically diverse aryldiazo esters, ketones, and amides can be accessed. Pyridine dramatically enhances the rate of the reaction by solubilizing the copper catalyst and serving as the Br?nsted base in the turnover-limiting proton-coupled oxidation of hydrazone by copper(II). Insights gained from mechanistic studies led to expansion of the scope of this method to include diaryl hydrazones, delivering diaryl diazomethane derivatives, which cannot be accessed via established diazo transfer methods. The products of this method may be employed in rhodium carbene catalysis without isolation of the diazo intermediate to afford cyclopropane products in good yield with high enantioselectivity.
Construction of 2-alkynyl aza-spiro[4,5]indole scaffolds: Via sequential C-H activations for modular click chemistry libraries
Zhang, Jun,Wang, Mengmeng,Wang, Huiying,Xu, Hui,Chen, Junjie,Guo, Ziqiong,Ma, Biao,Ban, Shu-Rong,Dai, Hui-Xiong
, p. 8656 - 8659 (2021/09/04)
Herein, we have developed a strategy of sequential C-H activations of indole to construct novel 2-alkynyl aza-spiro[4,5]indole scaffolds, which incorporated both alkyne and spiro-units into indole. Gram-scale synthesis and a one-pot, three-step synthesis demonstrated the utility of this protocol. Hybrid conjugates with an oseltamivir derivative further offered a powerful tool for the construction of a versatile spiroindole-containing library via click chemistry. This journal is