Photosynthesis and properties of halomethyl derivatives of azinobenzimidazoles

摘要

Photocyclization of 2-(pentafluoroanilino)-,2-(4-chloro-2-iodoanilino)-, and 2-(2-chloro-4-iodoanilino)-4,6-dimethylpyrimidines, as well as 2-(2-chloro-3-methylanilino)pyridine was used to prepare condensed azinobenzimidazoles, including previously unknown 8-chloro-1,3-dimethylpyrimido[1,2-a]benzimidazole and 9-methylpyrido[1,2-a]benzimidazole. With isomeric chloroiodoanilinopyrimidines as example it was shown that the iodine atom affects photocyclization direction. Quaternization of 6,7,8,9-tetrafluoro-1,3-dimethylpyrimido[1,2-a]benzimidazole, 8-chloro-1,3-dimethylpyrimido[1,2-a]benzimidazole, and 9-methylpyrido[1,2-a]benzimidazole with alkylating agents and C-H activity of alkyl groups in the quaternary salts in reactions with orthoformic ester were studied.