Copper-catalyzed aerobic oxidative coupling: From ketone and diamine to pyrazine
Keyword(s):
X Ray
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Copper-catalyzed aerobic oxidative C–H/N–H coupling between simple ketones and diamines was developed toward the synthesis of a variety of pyrazines. Various substituted ketones were compatible for this transformation. Preliminary mechanistic investigations indicated that radical species were involved. X-ray absorption fine structure experiments elucidated that the Cu(II) species 5 coordinated by two N atoms at a distance of 2.04 Å and two O atoms at a shorter distance of 1.98 Å was a reactive one for this aerobic oxidative coupling reaction. Density functional theory calculations suggested that the intramolecular coupling of cationic radicals was favorable in this transformation.
2013 ◽
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pp. 18994-19001
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2014 ◽
Vol 118
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pp. 25284-25290
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pp. 487-492
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pp. 10807-10818
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pp. 5018-5025
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2009 ◽
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pp. 10350
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2018 ◽
Vol 25
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pp. 529-536
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