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Preparation of quinoxalines, dihydropyrazines, pyrazines and piperazines using tandem oxidation processes. | LitMetric

Alpha-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.

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http://dx.doi.org/10.1039/b307177bDOI Listing

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