Preparation of quinoxalines, dihydropyrazines, pyrazines and piperazines using tandem oxidation processes
作者:Steven A. Raw、Cecilia D. Wilfred、Richard J. K. Taylor
DOI:10.1039/b307177b
日期:——
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 reactive 1,2-dicarbonyl intermediates. Modifications of the procedure allow the formation of pyrazines and piperazines.
α-羟基酮在MnO2介导的氧化下,随后与芳香或脂肪族1,2-二胺原位捕获,分别生成喹喔啉或二氢吡嗪,这一过程在一个反应釜中完成,避免了分离高度反应性1,2-二酮中间体的需要。对该工艺的修改可以生成吡嗪和吡咯啉。