High nitrogen chemistry: Synthesis and properties of N,N-bis(4,5-dicyano-1-methyl-2-imidazolyl)cyanamide and N,N,N′,N′,N″,N″-hexakis(4,5-dicyano-1-methyl-2-imidazoly)melamine

Abstract

Cyanation of bis(4,5-dicyano-1-methyl-2-imidazoly)amine( 1) using cyanogen chloride gave N,N-bis(4,5-dicyano-1-methyl-2-imidazolyl)cyanamide( 3) as a light yellow solid. Compound 3 is thermally labile and upon heating the NCN bond is cleaved and the reactive amine intermediate readily reacts with the moisture giving 1. Nucleophilic aromatic substitution(S NAr) reaction of the sodium salt of 1 with cyanuric chloride gave N,N,N′,N′,N″,N″-hexakis(4,5-dicyano-1-methyl-2-imidazolyl)melamine( 5), as a white microcrystalline solid. Compound 5 is thermally stable up to 300°C in nitrogen and air. Compound 5 showed strong emission bands at 476 nm in acetonitrile and 448 nm in DMF. Therefore, 5 may be used as a fluorescent probe.