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A Suitable Functionalization of Nitroindazoles with Triazolyl and Pyrazolyl Moieties via Cycloaddition Reactions.

ABSTRACT: The alkylation of a series of nitroindazole derivatives with 1,2-dibromoethane afforded the corresponding N-(2-bromoethyl)- and N-vinyl-nitro-1H-indazoles. The Cu(I)-catalysed azide- alkyne 1,3-dipolar cycloaddition was selected to substitute the nitroindazole core with 1,4-disubstituted triazole units after converting one of the N-(2-bromoethyl)nitroindazoles into the corresponding azide. The reactivity in 1,3-dipolar cycloaddition reactions with nitrile imines generated in situ from ethyl hydrazono-?-bromoglyoxylates was studied with nitroindazoles bearing a vinyl unit. The corresponding nitroindazole-pyrazoline derivatives were obtained in good to excellent yields.

SUBMITTER: Eddahmi M

PROVIDER: S-EPMC6983193 | biostudies-literature | 2019 Dec

REPOSITORIES: biostudies-literature

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A Suitable Functionalization of Nitroindazoles with Triazolyl and Pyrazolyl Moieties via Cycloaddition Reactions.

Eddahmi Mohammed M Moura Nuno M M NMM Bouissane Latifa L Amiri Ouafa O Faustino M Amparo F MAF Cavaleiro José A S JAS Mendes Ricardo F RF Paz Filipe A A FAA Neves Maria G P M S MGPMS Rakib El Mostapha EM

Molecules (Basel, Switzerland) 20191228 1

The alkylation of a series of nitroindazole derivatives with 1,2-dibromoethane afforded the corresponding N-(2-bromoethyl)- and N-vinyl-nitro-1H-indazoles. The Cu(I)-catalysed azide- alkyne 1,3-dipolar cycloaddition was selected to substitute the nitroindazole core with 1,4-disubstituted triazole units after converting one of the N-(2-bromoethyl)nitroindazoles into the corresponding azide. The reactivity in 1,3-dipolar cycloaddition reactions with nitrile imines gener ...[more]

PMID: 31905680

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