The N-nitrosopyridinium cation (PyNO') forms a series of intermolecular EDA complexes with aromatic hydrocarbons which show distinctive charge-transfer absorption bands in the visible region. Upon standing at room temperature, the EDA complexes in acetonitrile undergo a redox transformation into nitric oxide and oxidative pyridine adducts at the ips0 positions of such electronrich donors as 1,4-dimethylnaphthalene and durene-the latter of which has been structurally characterized by X-ray crystallography. Since the same adducts are formed when the EDA complexes (at low temperatures) are deliberately irradiated at their charge-transfer absorption bands, an electrontransfer mechanism is readily delineated for both the thermal and photochemical activation of the aromatic EDA complexes with PyNO'.The nitronium ion (NO,+) and the nitrosonium ion (NO') are the most active electrophiles for effecting the nitration and nitrosation, respectively, of different aromatic substrates. ' 9 ' As coordinatively unsaturated cations, NO, + and NO' are subject to ready anation to form neutral adducts (such as nitryl chloride and nitrosyl chlorides from chloride salt^),^ and they Paper 3/06 1 7 1 J
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.