Heterocycles nitrogen containing, acridine

Fragment ions Nitrogen-containing heterocyclics, such as pyridines, quinolines, and acridines, lose HCN and/or H2CN from their molecular ions. 

Compounds called azarenes containing one or more heterocyclic nitrogen atoms (e.g. pyridine, quinoline, acridine) have low-lying n —> n transitions, which explains their relatively low fluorescence quantum yields in hydrocarbons. 

Examples of the addition of solvent molecules to nitrogen-containing heterocycles, arising via initial hydrogen abstraction from the solvent, have again been described. The mechanism of this reaction with reference to six-membered aza-aromatic compounds has been the subject of a recent review,137 and in the reaction of acridine with alcohols and ethers, a radical-pair intermediate has been detected.138 Hydrogen abstraction is also implicated in the conversion of 4-quino-linecarbonitrile (172) into the alcohol (173) on irradiation in ethanol 139 the... 

Hydrodenitrogenation. Heterocyclic compounds containing nitrogen in coal liquids are either basic (pyridines, quinolines and acridines) or non-basic (pyrroles, indoles and carbazoles). Attempts have been made to study these model compounds to highlight the mechanism involved in hydrodenitrogenation process. 

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