Synthesis of 1,2-diamino imidazole derivatives by the reaction of benzaldehyde guanylhydrazone with ?-haloalkyl aryl ketones

Abstract

2-Amino-1-benzylideneamino-4-arylimidazoles were obtained by the reaction of benzaldehyde guanylhydrazone with 4-alkyl- and 4-aryl-Ω-haloacetophenones. Side products of this reaction were cis- and trans-1,1′-bis(benzylideneamino)-4,4′-diaryl-2,2′-azoimidazoles. The corresponding 2-amino-1-benzylideneaminoimidazole and 1-benzyl-ideneaminoimidazo[l,2-a]imidazole were obtained in the reaction of α-bromopropiophenone with benzaldehyde guanylhydrazone. The 2-amino-1-benzylideneamino-4-arylimidazoles were converted by successive reactions to 1,2-diatnino-4-arylimidazoles and then to imidazo[1,2-b]-1,2,4-triazine derivatives —dyes for liquid crystals with positive dichroism.