This communication expresses aromatisation of 1,4-dihydropyridines to pyridine derivatives with the help of alumina supported benzimidazolium fluorochromate (BIFC) and quinolinium fluorochromate (QFC) as oxidants undersolvent-free microwave irradiation. Moderate to excellent yield (80-98%) of pyridine derivatives were achieved by this methodology.
Oxidative aromatization of Hantzsch 1,4-dihydropyridines by cupric bromide under mild heterogeneous condition
作者:Forid Saikh、Rimpa De、Somnath Ghosh
DOI:10.1016/j.tetlet.2014.09.025
日期:2014.11
A mild heterogeneous oxidizing agent, cupricbromide has been utilized for the oxidative aromatization of Hantzsch 1,4-dihydropyridines to the corresponding pyridine derivatives in excellent yields with the isolation of products by simple work-up procedure.
A variety of Hantzschester1,4-dihydropyridines are efficiently oxidized to their corresponding pyridine compounds with iodineundernormalconditions and ultrasoundirradiation. The reactions were carried out in refluxing CH 3 CN.
Aromatization of 1,4-dihydropyridines with selenium dioxide
作者:Xiao-hua Cai、Hai-jun Yang、Guo-lin Zhang
DOI:10.1139/v05-058
日期:2005.3.1
1,4-Dihydropyridines were aromatized to corresponding pyridinesusing stoichiometric selenium dioxide at ambient temperature in a yield of 87%~98%.Key words: 1,4-dihydropyridines, aromatization, oxidation, pyridine derivatives, selenium dioxide.