annulation cascade of unactivated N-alkene-linked indoles with Langlois’ reagent by a radical relay is developed at room temperature under blue LED irradiation. The reaction afforded a series of tri/difluoromethylated pyrrolo[1,2-a]indoles in moderate to good yields. The DFT study suggests that the reaction is ascribed to a rhodamine 6G-induced cyclization cascade involving vinyl addition-radical relay
在室温下,在蓝光 LED 照射下,通过自由基中继,形成了未活化的N-烯烃连接的吲哚与 Langlois 试剂的光催化成环级联。该反应以中等至良好的产率提供了一系列三/二氟甲基化吡咯并[1,2- a ]吲哚。 DFT 研究表明,该反应归因于罗丹明 6G 诱导的环化级联,涉及乙烯基加成自由基中继和氢原子抽象 (HAA) 过程,有趣的是,吡咯并[1,2- a ]吲哚被用作荧光染料进入荧光光谱和活细胞成像。本文展示了通过自由基中继和 HAA 过程进行光催化环化级联的初始示例。
Photoinduced radical-polar-crossover cyanomethylation-cyclization cascade of unactivated N-alkene-linked indoles with bromoacetonitrile towards cyanomethylated pyrrolo[1,2-a]indoles
Unactivated -alkene-linked indoles were established as general substrates for cyanomethylation-cyclization cascade reactions with bromoacetonitrile in a photoinduced condition, generating diverse cyanomethylated pyrrolo[1,2-]indoles with a broad substrate scope in moderate to good yields. The mechanistic study revealed that radical addition, cyclization and radical-polar-crossover (RPC) process were
Modern drug discovery has created an increasing demand for new methods of trifluoromethylation. Herein a novel method for the synthesis of trifluoromethylated fused tricyclic indoles by copper(I) iodide as catalyst has been successfully developed under mild conditions. The corresponding trifluoromethyl indoles were obtained with good to excellent yields (62-89%) and the reaction applies to a different range of functional groups. (C) 2015 Elsevier Ltd. All rights reserved.
A copper-catalyzed domino radical cyclization route to benzospiro-indolizidinepyrrolidinones
作者:Christian V. Stevens、Ellen Van Meenen、Kurt G.R. Masschelein、Yves Eeckhout、Wim Hooghe、Bart D’hondt、Victor N. Nemykin、Viktor V. Zhdankin
DOI:10.1016/j.tetlet.2007.07.211
日期:2007.10
In this Letter the synthesis of benzospiro-indolizidinepyrrolidinones is described by a domino atom transfer radical cyclization reaction using a copper catalyst. The structure of one of the products was established by single crystal X-ray diffraction. The investigated precursors, bearing a homo allyl substituent on the N-indole, result in a 5-exo-trig, followed by a 6-endo-trig cyclization. When the N-indole is substituted with an allyl group, only the spiro-cyclization occurs. (c) 2007 Elsevier Ltd. All rights reserved.
Radical cyclisation of dienes and enynes using TolSO2SePh
作者:Julie E. Brumwell、Nigel S. Simpkins、Nicholas K. Terrett
DOI:10.1016/s0040-4039(00)77533-2
日期:1993.2
Reaction of a number of 1,6-diene or enyne systems with TolSO2SePh, under free radical conditions, results in selenosulphonylation with concommitant C-C bond formation, to give cyclised alkyl or vinyl sulphones containing the synthetically useful phenylselenyl functionality.