68240-87-9Relevant academic research and scientific papers
Photoreactions of 4,5-diarylimidazoles: Singlet oxygenation and cyclodehydrogenation
Purushothaman, E.,Pillai, V. N. Rajasekharan
, p. 290 - 293 (2007/10/02)
4,5-Diarylimidazoles (1) undergo singlet oxygenation and cleavage to give N,N'-diaroylureas (2) on irradiation in alcoholic solutions in the presence of methylene blue as sensitizer. 5-Methoxy-4,5-diphenylimidazolin-2-one (5) and 4,5-dimethoxy-4,5-diphenylimidazolidin-2-one (6) have been reported as the principal products in the dye-sensitized irradiation of 4,5-diphenylimidazole in methanol.The formation of diaroylureas appears to proceed through the intermediacy of the corresponding imidazolin-2-one.A mechanistic pathway for the photochemical dye-sensitized oxygenation of the imidazoles is suggested.The photochemical cyclodehydrogenation reaction of the stilbene system present in 4,5-diarylimidazoles has also been carried out.
Chlorinated imidazole derivatives and a process for preparing them
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, (2008/06/13)
Imidazole derivatives, useful as intermediates for making herbicides, having the formula STR1 wherein X is chlorine, lower alkyl mono- or polysubstituted by chlorine, or aryl which is optionally mono- or polysubstituted by halogen and/or lower alkyl and R1 and R2 are identical or different and are chlorine or phenyl optionally substituted by halogen and/or lower alkyl. The imidazole derivatives are prepared by converting an imidazole derivative having the formula STR2 wherein X' is hydrogen, lower alkyl or aryl optionally substituted by halogen atom and/or lower alkyl and R'1 and R'2 are identical and represent hydrogen and/or phenyl optionally substituted by halogen and/or lower alkyl By means of hydrogen chloride, in the absence of water, into the corresponding hydrochloride, subsequently reacting with hydrochloride with an excess of chlorine at elevated temperature.
