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Sequential, Electrochemical-Photochemical Synthesis of 1,2,4-Triazolo-[4,3-a]pyrazines
Joseph Yount1,2, Megan Morris3, Noah Henson4
1School of Materials Engineering, Purdue University, 205 Gates Road, West Lafayette, IN, 47906, USA.
Abstract:
1,2,4-triazolo-[4,3-a]pyrazine was prepared via a two-step electrochemical, photochemical process. First, a 5-substituted tetrazole is electrochemically coupled to 2,6-dimethoxypyrazine to yield 1,5- and 2,5- disubstituted tetrazoles. Subsequent photochemical excitation of the 2,5-disubstituted tetrazole species using an ultraviolet lamp releases nitrogen gas and produces a short-lived nitrilimine intermediate. Subsequent cyclization of the nitrilimine intermediate yields a 1,2,4-triazolo-[4,3-a]pyrazine backbone. The scope of this reaction was explored using various tetrazoles and pyrazines. Materials produced were identified using chemical analytical techniques and computationally studied for potential application as an insensitive energetic material.
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