Transformations of 3-aryl-2-chloro-2-imidoylaziridines: novel entries to 4-chloro-2,5-diaryl-1H-imidazoles and 2-chloro-2-acylaziridines
作者:Filip Colpaert、Sven Mangelinckx、Nicola Giubellina、Norbert De Kimpe
DOI:10.1016/j.tet.2010.11.082
日期:2011.2
The reactivity of stereochemically defined 3-aryl-2-chloro-2-imidoylaziridines, an unexplored class of substituted aziridines, was investigated under various reaction conditions. 2-Chloro-2-imidoylaziridines underwent a novel thermal rearrangement by reflux in acetonitrile via C–C bond cleavage to 4-chloro-2,5-diarylimidazoles in high yield. Alternatively, a novel efficient entry toward 2-aroyl-2-chloroaziridines
Aluminum Chloride Mediated Reactions of N-Alkylated Tosylhydrazones and Terminal Alkynes: A Regioselective Approach to 1,3,5-Trisubstituted Pyrazoles
作者:Meng Tang、Yun Wang、Hu Wang、Yuanfang Kong
DOI:10.1055/s-0035-1561646
日期:——
Abstract Aluminum chloridemediated reactions of N-alkylated tosylhydrazones and terminal alkynes are reported. The protocol is applied to a wide range of substrates, and demonstrates excellent functional group tolerance. A series of 1,3,5-trisubstituted pyrazoles is prepared in good to high yields with complete regioselectivity. Aluminum chloridemediated reactions of N-alkylated tosylhydrazones and
This application relates to a process for the preparation of substituted and unsubstituted 1-alkyl-3,5-diphenylpyrazole compounds by reacting a 3,5-diphenyl (substituted or unsubstituted) pyrazole with an excess of dialkyl sulfate, in the presence of aqueous alkali hydroxide and a quaternary ammonium phase transfer catalyst.