Reaction of substituted anthracenes and a butadiene with nitric oxide: product formation determined by EPR spectroscopy.
When nitric oxide (NO), generated from nitric acid and copper, was reacted with a series of 9,10-substituted anthracenes, only 9,10-dimethylanthracene gave EPR detectable nitroxide radicals, although the expected bicyclic nitroxide arising from cheletropic NO addition across the 9,10-positions was not observed. Purity of the NO is crucial as the presence of higher oxides of nitrogen leads to radicals by hydrogen abstraction which are trapped by NO and the resultant nitroso compounds produce stable nitroxides detectable by EPR. In contrast the acyclic system, 3,4-diphenyl-2,5-dimethyl-2,4-hexadiene gives rise to an EPR spectrum consistent with cheletropic NO addition, although higher oxides of nitrogen again mediate the formation of different nitroxides.
Pfeiler
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CIDC, School of Chemistry, Queensland University of Technology, Brisbane, Australia.
Grice
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Bottle
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Hanson
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GR
D000873:Anthracenes / Q000737:chemistry*; D002070:Butadienes / Q000737:chemistry*; D004578:Electron Spin Resonance Spectroscopy; D009569:Nitric Oxide / Q000737:chemistry*
D000873:Anthracenes; D002070:Butadienes; D009569:Nitric Oxide