Studies on Melamine Derivatives. IV

Acylation of Melamine with Nitrobenzoic Anhydrides

Abstract

Diacetylmelamine and o-(or m- or p-) nitrobenzoic anhydride (NBA) in the molar ratio of 1: 2 are reacted by fusion at around 200°C to obtain mono-o-onitrobenzoyl-diacetylmelamine (1) or corresponding m-isomer (2) and p-isomer (3). A partial saponification of (1), (2), and (3) with 5% aqueous solution of sodium hydroxide yielded mono-o-nitrobenzoylmelamine (4), and corresponding m-(5) and p-isomer (6), respectively. These mono-substituted products are also obtainable by boiling melamine (M) in dioxane and o-(or m- or p-) NBA in the molar ratio of 1: 2. Reaction of (4) and o-NBA, (5) and m-NBA, and (6) and p-NBA in dioxane yielded di-o-nitrobenzoylmelamine (7), and corresponding m-iosmer (8), and p-isomer (9). Reaction by fusion of M and o-NBA at around 160°C M and m- and p-NBA at around 200°C in their molar ratio of 1: 4.5 yielded tri-o-nitrobenzoylmelamine 10), and corresponding misomer 11), and p-isomer (12). The products (1)-(12) are new compounds.