930781-40-1Relevant articles and documents
One-Pot Protocol for the Synthesis of Imidazoles and Quinoxalines using N-Bromosuccinimide
Pardeshi, Sachin D.,Sathe, Pratima A.,Vadagaonkar, Kamlesh S.,Chaskar, Atul C.
supporting information, p. 4217 - 4226 (2017/12/07)
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 the N-arylbenzamidine and o-phenylenediamine. Use of an inexpensive NBS as a bromine source as well as an oxidant, water as a solvent and readily available starting materials makes this protocol environmentally benign and economically viable. Substituted imidazoles and quinoxalines were obtained in good to excellent yields with wide functional group compatibility. (Figure presented.).
I2 catalyzed tandem protocol for synthesis of quinoxalines via sp3, sp2 and sp C-H functionalization
Vadagaonkar, Kamlesh S.,Kalmode, Hanuman P.,Murugan, Kaliyappan,Chaskar, Atul C.
, p. 5580 - 5590 (2015/02/05)
One-pot, atom-economic synthesis of quinoxalines has been achieved through generation of arylglyoxal from 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 domino reaction involving C-H functionalization/oxidative cyclization. This metal-free, mechanistically distinct and functional group tolerant tandem approach could be a powerful complement to traditional approaches for the synthesis of quinoxalines. This journal is
Synthesis of functionalized benzimidazoles and quinoxalines catalyzed by sodium hexafluorophosphate bound Amberlite resin in aqueous medium
Ghosh, Pranab,Mandal, Amitava
supporting information, p. 6483 - 6488,6 (2012/12/12)
A very simple, eco-friendly, and versatile method for the selective synthesis of 1,2-disubstituted benzimidazoles and quinoxalines in water-methanol (1:1) mixture with the aid of resin bound hexafluorophosphate ion as catalyst is reported. The method is also effective for the incorporation of quinoxaline nucleus at the A ring of pentacyclic triterpenoid, friedelin. A plausible mechanism for the formation of disubstituted benzimidazole has also been suggested.
