474537-07-0Relevant academic research and scientific papers
Efficient pyrido[1,2-a]benzimidazole formation from 2-aminopyridines and cyclohexanones under metal-free conditions
Xie, Yanjun,Wu, Jun,Che, Xingzong,Chen, Ya,Huang, Huawen,Deng, Guo-Jun
supporting information, p. 667 - 671 (2016/02/12)
An efficient procedure for pyrido[1,2-a]benzimidazole preparation from 2-aminopyridines and cyclohexanones under metal-free conditions is described. Non-aromatic cyclohexanones were used as the aryl source via a dehydrogenation-aromatization process using molecular oxygen as the green oxidant.
A metal-free tandem demethylenation/C(sp2)-H cycloamination process of N -Benzyl-2-aminopyridines via C-C and C-N bond cleavage
Liang, Dongdong,He, Yimiao,Liu, Lanying,Zhu, Qiang
, p. 3476 - 3479 (2013/07/26)
A mild, metal-free synthesis of pyrido[1,2-a]benzimidazoles starting with N-benzyl-2-aminopyridines, which employs PhI(OPiv)2 as a stoichiometric oxidant, has been developed. The process is initiated by an unusual PhI(OPiv)2-mediated ipso SEAr reaction, followed by solvent-assisted C-C and C-N bond cleavage.
Photosynthesis and properties of halomethyl derivatives of azinobenzimidazoles
Frolov
, p. 464 - 471 (2007/10/03)
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.
