Abstract Pyrazine-2, 3-dicarbonitrile (1) reacts with alkyl radicals to give mono-3 and di- alkylated pyrazine-2, 3-dicarbonitriles 4. Similarly 1, 3-dimethyllumazine (2) reacts with alkyl radicals to give 7-alkyl-1, 3-dimethyllumazines 8 as the major product. The reactivity of alkyl radicals decreases in the order tertiary, secondary, and primary, and 1 is more reactive than 2 in those radical substitution reactions.
