78460-97-6Relevant academic research and scientific papers
S-Demethylation of Nitrogen Heterocycles
Chen, Shih-Fong,Panzica, Raymond P.
, p. 303 - 307 (2007/10/02)
When 3-chloro-4,5-diaminopyridazine (2) was treated with sodium methylmercaptide in refluxing N,N-dimethylformamide, two heterocycles were formed and isolated, neither of which was the expected 3-methylthio-4,5-diaminopyridazine (3).A thorough spectral analysis of these heterocycles showed them to be 4-methylthioimidazopyridazine (5) and imidazopyridazine-4-thione (6).N,N-Dimethylformamide was found to provide the one carbon unit required for the formation of 5.The origin of 6 was shown to be a result of S-demethylation of 5.S-Demethylation of 3 could also be effected with sodium methylmercaptide in methyl sulfoxide without the occurrence of annulation.In methyl sulfoxide the process of demethylation was accelerated and occurred at lower temperature.
