1,2-Addition to trifluoromethylated ß-enamino diketones: regioselective synthesis of trifluoromethyl-containing azomethine pyrazoles and isoxazoles.
Org Biomol Chem
; 18(13): 2524-2537, 2020 04 01.
Article
em En
| MEDLINE
| ID: mdl-32196053
A simple and efficient methodology for highly regioselective synthesis of azomethine pyrazoles and isoxazoles containing a trifluoromethyl group is reported. The cyclocondensation of trifluoromethylated ß-enamino diketones (TBED) with phenylhydrazine and hydroxylamine hydrochloride, in the presence of BF3, provided 5-aryl-4-[(tert-butyl)iminomethyl]-3-trifluoromethylazoles by aza-Michael-type 1,2-addition. The scope of the reaction was expanded by transimination with arylamines in a one-pot method starting from TBED. Thus, 83 novel 4-[(alkyl/aryl)iminomethyl]-3-trifluoromethylazoles were obtained with high regioselectivity and in yields of 51 to 89%.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Idioma:
En
Revista:
Org Biomol Chem
Assunto da revista:
BIOQUIMICA
/
QUIMICA
Ano de publicação:
2020
Tipo de documento:
Article
País de afiliação:
Brasil
País de publicação:
Reino Unido