163428-97-5Relevant academic research and scientific papers
An efficient and convenient protocol for the synthesis of quinoxalines and dihydropyrazines via cyclization-oxidation processes using HClO4·SiO2 as a heterogeneous recyclable catalyst
Das, Biswanath,Venkateswarlu, Katta,Suneel, Kanaparthy,Majhi, Anjoy
, p. 5371 - 5374 (2007)
A convenient and straightforward method has been developed for the synthesis of quinoxalines and dihydropyrazines (DHPs) using α-bromo ketones and 1,2-diamines in the presence of silica supported perchloric acid (HClO4·SiO2) at room temperature. The quinoxalines and DHPs were presumably formed via cyclization-oxidation. The catalyst works under heterogeneous conditions and can be recycled.
Preparation of quinoxalines, dihydropyrazines, pyrazines and piperazines using tandem oxidation processes
Raw, Steven A.,Wilfred, Cecilia D.,Taylor, Richard J. K.
, p. 2286 - 2287 (2003)
α-Hydroxyketones undergo MnO2-mediated oxidation followed by in situ trapping with aromatic or aliphatic 1,2-diamines to give quinoxalines or dihydropyrazines, respectively, in a one pot procedure which avoids the need to isolate the highly rea
Asymmetric Hydrogenation of 2-Aryl-5,6-dihydropyrazine Derivatives with Chiral Cationic Ruthenium Diamine Catalysts
Li, Yong,He, Yanmei,Chen, Fei,Fan, Qinghua
, p. 991 - 994 (2016/02/18)
The first asymmetric hydrogenation of unfunctionalized 2-substituted and 2,3-disubstituted 5,6-dihydropyrazines catalyzed by chiral cationic Ru-diamine complex (R,R)-1a was developed, affording chiral piperazine derivatives with good enantioselectivities (up to 89% ee).
Tandem oxidation processes for the preparation of nitrogen-containing heteroaromatic and heterocyclic compounds
Raw, Steven A.,Wilfred, Cecilia D.,Taylor, Richard J.K.
, p. 788 - 796 (2007/10/03)
α-Hydroxy ketones undergo manganese dioxide-mediated oxidation followed by in situ trapping with aromatic or aliphatic 1,2-diamines to give quinoxalines or dihydropyrazines, respectively, in a one-pot procedure which avoids the need to isolate the highly reactive dicarbonyl intermediates. The scope and limitations of these procedures are outlined and modifications to this procedure are discussed in which reduction is carried out in the same reaction vessel, generating piperazines, or oxidation, leading to pyrazines.
