Nucleophilic Nitration of Selected Aza-aromatics: Experiments and Modelling
نویسندگان
چکیده
Nitration of isoquinoline and phthalazine has been successfully demonstrated using a novel process which does not require strong acids. In this study, nitration of isoquinoline was repeated and the method applied to 1-nitroisoquinoline and the azaaromatics quinoline, quinazoline, quinoxaline and pyridine. Nitration of only quinoline was observed, with a product yield lower than that reported for nitration of isoquinoline. For 1-nitroisoquinoline and quinoxaline, the substrates were recovered essentially unchanged. For quinazoline and pyridine, neither the substrates nor any reaction products were isolated. In no case was multiple nitration detected. Thus, while the scope of the reaction is broader than initially reported, it is clearly not a universal method for nitrating aza-aromatics. Molecular modelling calculations have identified a correlation between the acidity of the intended nitration site and the observed yield, which might be used to screen potential substrates for this nitration technique.
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