Reductive debromination of 1-methyl-2,4,5-tribromoimidazole mediated by dry tetramethylammonium fluoride in aprotic solvents
Document title: Reductive debromination of 1-methyl-2,4,5-tribromoimidazole mediated by dry tetramethylammonium fluoride in aprotic solvents
Journal: Journal of the Brazilian Chemical Society
Database: PERIÓDICA
System number: 000310988
ISSN: 0103-5053
Authors: 1

2

3
Institutions: 1Fundacao Oswaldo Cruz, Far-Manguinhos, Rio de Janeiro. Brasil
2Universidade Federal do Rio de Janeiro, Instituto de Quimica, Rio de Janeiro. Brasil
3Toyama Medicinal and Pharmaceutical University, Faculty of Pharmaceutical Sciences, Toyama. Japón
Year:
Season: Jun
Volumen: 12
Number: 3
Pages: 417-421
Country: Brasil
Language: Inglés
Document type: Artículo
Approach: Experimental, aplicado
English abstract The reaction of dry tetramethylammonium fluoride (TMAF) with 1-methyl-2,4,5-tribromoimidazole in different polar aprotic solvents was investigated. Products of reductive debromination were obtained rather than fluorine substitution, indicating that TMAF is strongly basic in such conditions. A reaction carried out in d6-DMSO showed that the solvent is the proton source. Dimethylformamide was less effective that DMSO, N,N-dimethylacetamide or N-methylpirrolidone as a proton donor and we were able to effect significant fluorination in this solvent
Portuguese abstract Neste trabalho investigou-se a reação entre fluoreto de tetrametilamônio seco (TMAF) e 1-metil-2,4,5-tribromoimidazol em diferentes solventes apróticos polares. Nas reações feitas em DMSO, N,N-dimetilacetamida e N-metilpirrolidona, os principais produtos foram provenientes da desbrominação redutiva e não da fluoração, como esperado, mostrando que o TMAF é fortemente básico nestas condições. A reação feita em DMSO deuterado mostrou que o solvente é a principal fonte de próton. A dimetilformamida foi o solvente menos efetivo como doador de prótons, mas forneceu um rendimento significativo do produto fluorado 4,5-dibromo-2-flúor-1-metilimidazol
Disciplines: Química
Keyword: Química farmacéutica,
Química orgánica,
Debrominación reductora,
Tribroimidazol,
Fluoroimidazol
Keyword: Chemistry,
Medicinal chemistry,
Organic chemistry,
Reductive debromination,
Tribroimidazole,
Fluoroimidazole
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