Acetic Anhydride → 5-(4-Acetamidophenyl)-3-methyl-2(1H)-pyrazinone

Participants

Reaction Steps

5-(4-Aminophenyl)-3-methyl-2(1H)-pyrazinone hydrobromide (1.0 g) in water (25 ml) was treated with acetic anhydride and sodium acetate in a similar manner to that described in Example 3. On recrystallisation from aqueous acetic acid the title compound (0.68 g) had m.p.>300° C.; δ(DMSO-d6) inter alia 2.08 (3H,s, CO--CH3), 2.39 (3H, d, 3-CH3), 10.0 (1H, s, NHCO); ν(Nujol mull) 1655 (C=0) cm-1.

Provenance & Evidence