6158-99-2Relevant articles and documents
Chemoselective synthesis of quinoxalines and benzimidazoles by silica gel catalysis
Li, Chunmei,Zhang, Furen,Yang, Zhen,Qi, Chenze
supporting information, p. 5430 - 5433 (2014/12/11)
Treatment of nitroolefins and o-phenylenediamine with silica gel catalyst produced quinoxalines mainly in THF, but gave benzimidazoles efficiently in water. Such a solvent-dependent chemoselective reaction has prominent features of affording two cyclized products selectively with the same substrate, short reaction time, operational simplicity, as well as available starting materials and nontoxic catalysts. In addition, the scope and limitations were explored and a plausible reaction mechanism is proposed.
DABCO-catalyzed oxidation of deoxybenzoins to benzils with air and one-pot synthesis of quinoxalines
Qi, Chaorong,Jiang, Huanfeng,Huang, Liangbin,Chen, Zhengwang,Chen, Huoji
experimental part, p. 387 - 396 (2011/04/15)
Aerobic oxidation of deoxybenzoins could be efficiently catalyzed by 1,4-diazabicyclo[2.2.2]octane (DABCO) with air as the sole oxidant to give the corresponding benzils in excellent yields. The effects of reaction conditions, such as different bases, temperature, time and solvent, on the yield of the product were investigated. Moreover, the process has been successfully extended to a one-pot synthesis of quinoxalines from benzyl ketones and aromatic 1,2-diamines. Georg Thieme Verlag Stuttgart New York.
