Comins, D. L., O Connor, S., Regioselective Substitution in Aromatic Six-Membered

Comins, D. L., O Connor, S., Regioselective Substitution in Aromatic Six-Membered Nitrogen Heterocycles, 44, 199. 

C-substitution of nitrogen heterocycles , Vorbriiggen, H. and Maas, M., Heterocycles, 1988, 27, 2659 (discusses electrophilic and radical substitutions, lithiations and the use of iV-oxides) Regioselective substitution in aromatic six-membered nitrogen heterocycles , Comins, D. L. and O Connor, S., Adv. Heterocycl. Chem., 1988, 44, 199 (discusses electrophilic, nucleophilic and radical substitution, and metallation). 

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