Alkylation of pyridine-3,5-dicarboxamide and pyridine-3,5-dicarbonitriles by radical substitution

Structural modification of NAD(P) model compounds, N,N,N',N'-tetramethylpyridine-3,5-dicarboxamide ( 1 ), pyridine-3,5-dicarbonitrile ( 2 ), and 4-methylpyridine-3,5-dicarbonitrile ( 3 ), have been explored by the reaction with alkyl radicals such as the 1-adamantyl, tert-butyl, and isopropyl radicals. The alkyl substitutions of compounds 1 , 2 , and 3 with the 1-adamantyl and the tert-butyl radical gave both 2-mono and 2,6-disubstitution products, whereas the reaction of compound 2 with the isopropyl radical gave 2-mono 6c , 2,4-di 7c, 2,6-di 8c , and 2,4,6-trisubstitution 9c products.