Elemental Sulfur Mediated Synthesis of Pyrrolo[1,2-a]quinoxalines from 1-(2-Nitroaryl)pyrroles
作者:Tung T. Nguyen、Nam T. S. Phan、Tuan H. Ho、Nhu T. A. Phan、Thuyen T. C. Ho、Duyen L. M. Tran
DOI:10.1055/a-1534-0466
日期:2021.11
Methods to afford pyrrolo[1,2-a]quinoxalines often require the use of prefunctionalized aniline precursors, transition metals, and/or harsh conditions. Herein we describe a simple coupling of 1-(2-nitroaryl)pyrroles and arylacetic acids, in the presence of elemental sulfur, to furnish the fused heterocycles in good yields. The conditions are compatible with many functionalities including ester, nitrile
Direct Synthesis of Pyrrolo[1,2-α]quinoxalines <i>via</i> Iron-Catalyzed Transfer Hydrogenation between 1-(2-Nitrophenyl)pyrroles and Alcohols
作者:Simin Chun、Jiwon Ahn、Ramachandra Reddy Putta、Seok Beom Lee、Dong-Chan Oh、Suckchang Hong
DOI:10.1021/acs.joc.0c02145
日期:2020.12.4
Herein, we describe novel iron-catalyzed transferhydrogenation between alcohols and 1-(2-nitrophenyl)pyrroles for the synthesis of pyrrolo[1,2-α]quinoxalines. The tricarbonyl (η4-cyclopentadienone) iron complex catalyzed the oxidation of alcohols and the reduction of nitroarenes, and the corresponding aldehydes and aniline were generated in situ. The resulting Pictet–Spengler-type annulation/oxidation
A ruthenium-catalyzed [5+1] annulation of 1-(2-aminophenyl)pyrroles with α-carbonyl sulfoxonium ylides is reported. This reaction provides a one-step method for synthesizing pyrrolo[1,2-a]quinoxaline derivatives under ambient conditions. The system proceeds with a short reaction time and a high functional-group tolerance. Notably, this divergent protocol tolerates β-keto sulfoxonium ylides and can
Copper-Catalyzed Synthesis of Alkyl-Substituted Pyrrolo[1,2-a]quinoxalines from 2-(1H-Pyrrol-1-yl)anilines and Alkylboronic Acids
作者:Rulong Yan、Xin Guan
DOI:10.1055/s-0037-1610743
日期:2020.3
A radical pathway for the construction of pyrrolo[1,2-a]quinoxalines by using 2-(1H-pyrrol-1-yl)anilines and alkylboronic acids has been developed. Features of this process include Cu catalysis, readily accessible starting materials, and simple operations. Alkylboronic acids are used for the construction of pyrrolo[1,2-a]quinoxaline derivatives, and the desired products are obtained in moderate yields
Efficient synthesis of pyrrolo[1,2-a]quinoxalines catalyzed by a Brønsted acid through cleavage of C–C bonds
作者:Caixia Xie、Lei Feng、Wanli Li、Xiaojun Ma、Xinkun Ma、Yihan Liu、Chen Ma
DOI:10.1039/c6ob01401a
日期:——
An efficient and convenient one-pot domino reaction for the direct synthesis of pyrrolo[1,2-a]quinoxalines has been developed. This approach utilizes an imine formation reaction, SEAr reaction and cleavage of C–C bonds catalyzed by a Brønsted acid. β-Diketones and β-keto esters are both well tolerated to give the corresponding products in moderate to excellent yields.
已经开发了用于直接合成吡咯并[1,2- a ]喹喔啉的有效且方便的一锅多米诺反应。该方法利用用于形成亚胺的反应,S È氩反应和裂解由布朗斯台德酸催化的C-C键。β-二酮和β-酮酯均具有良好的耐受性,可以以中等至极好的收率得到相应的产物。