Visible light promoted tandem dehydrogenation-deaminative cyclocondensation under aerobic conditions for the synthesis of 2-aryl benzimidazoles/quinoxalines from <i>ortho</i>-phenylenediamines and arylmethyl/ethyl amines
作者:Firdoos Ahmad Sofi、Rohit Sharma、Ravi Rawat、Asit K. Chakraborti、Prasad V. Bharatam
DOI:10.1039/d0nj03002c
日期:——
Visible light promoted dominosynthesis of 2-aryl benzimidazoles is reported through the reaction of ortho-phenylenediamines and arylmethyl amines underaerobicconditions. The methodology has wide substrate scope and tolerates a wide range of functional groups affording the products in high yields. The use of arylethyl amines instead of arylmethyl amines gives 2-aryl quinoxalines.
I<sub>2</sub> catalyzed tandem protocol for synthesis of quinoxalines via sp<sup>3</sup>, sp<sup>2</sup> and sp C–H functionalization
作者:Kamlesh S. Vadagaonkar、Hanuman P. Kalmode、Kaliyappan Murugan、Atul C. Chaskar
DOI:10.1039/c4ra08589b
日期:——
One-pot, atom-economic synthesis of quinoxalines has been achieved through generation of arylglyoxalfrom easily available ethylarenes, ethylenearenes and ethynearenes, and subsequent condensation with o-phenylenediamines. Catalytic I2 with TBHP as an oxidant in DMSO is the system of choice for this dominoreaction involving C–H functionalization/oxidative cyclization. This metal-free, mechanistically
One-Pot Protocol for the Synthesis of Imidazoles and Quinoxalines using<i>N</i>-Bromosuccinimide
作者:Sachin D. Pardeshi、Pratima A. Sathe、Kamlesh S. Vadagaonkar、Atul C. Chaskar
DOI:10.1002/adsc.201700900
日期:2017.12.11
N‐bromosuccinimide (NBS)‐mediated one‐pot, green, efficient and practical synthesis of substituted imidazoles and quinoxalines has been achieved by the reaction of styrenes with N‐arylbenzamidines and o‐phenylenediamines, respectively, in a water:1,4‐dioxane mixture. The reaction involves formation of an α‐bromo ketone as an intermediate in the presence of NBS and water, followed by condensation with
Direct Aerobic Oxidative Reactions of 2-Hydroxyacetophenones
作者:Subas Chandra Sahoo、Utpal Nath、Subhas Chandra Pan
DOI:10.1002/ejoc.201700909
日期:2017.8.17
Metal-free and external-oxidant-free aerobicoxidative reactions of 2-hydroxyacetophenones are developed. The reactions are based on the aerobic formation of small equilibrium quantities of 2-keto aldehydes. Phthalides, quinoxalines, α-ketoamides, and olefins can be formed in moderate to good yields directly from alcohols. DIPEA = diisopropylethylamine.
Organocatalytic Green Approach Towards the Fabrication of Fused Benzo
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<i>N</i>
‐containing Heterocycles Facilitated by Ultrasonic Irradiation
作者:Ridaphun Nongrum、George Kupar Kharmawlong、Jims World Star Rani、Noimur Rahman、Arup Dutta、Rishanlang Nongkhlaw
DOI:10.1002/jhet.3680
日期:2019.10
transformations in organic synthesis offers a significant potential environmental benefit. This article reports the exploration of meglumine, a nontoxic and biodegradable amino sugar, as an organocatalyst for the synthesis of biologically active 1H‐dibenzo[b,e][1,4]diazepin‐1‐ones, highly regioselective benzimidazole derivatives and derivatives of quinoxalines. Operational simplicity, mild reaction conditions, shorter