Efficient synthesis of new 1-[Alkyl(aryl)]-5-(3,3,3-trihalo-2-oxopropylidene)pyrrolidin-2-ones

Abstract

Este trabalho mostra a síntese, em bons rendimentos (57-95%), de duas séries de 1-alquil(aril) amino-2-oxo-5-(2-oxo-3,3,3-trialopropiliden)-pirrolidinas 5 e 6, a partir dos intermediários 4-[alquil(aril)amino]-6-oxo-7,7,7-trialo-4-hepteno-atos de metila 3 e 4 obtidos por substituição da metoxila-nos precursores 4-metoxi-6-oxo-7,7,7-trialo-4-heptenoatos de metila 1 e 2, pela série de aminas primárias RNH 2 , onde R = PhCH 2 , PhCH 2 CH 2 , Ph, 4-MeC 6 H 4 , 4-MeOC 6 H 4 , 4-ClC 6 H 4 , 4-BrC 6 H 4 , 2-piridnil, 5-metil-3-isoxazolil, 4-NH 2 C 6 H 4 . A estrutura molecular dos produtos inéditos foi atribuída a partir dos dados de RMN 1 H, 13 C e espectrometria de massas. A configuração geométrica dos compostos 3d e 5b foi confirmada pelos dados de difração de raios-X em monocristal.Reactions of methyl 4-methoxy-6-oxo-7,7,7-trihalo-4-heptenoates 1 and 2 with primary amines RNH 2 , where R = PhCH 2 , PhCH 2 CH 2 , Ph, 4-MeC 6 H 4 , 4-MeOC 6 H 4 , 4-ClC 6 H 4 , 4-BrC 6 H 4 , 2-pyridyl, 5-methyl-3-isoxazolyl, 4-NH 2 C 6 H 4 affording methyl 4-[alkyl(aryl)amino]-6-oxo-7,7,7-trihalo-4-heptenoates 3, 4, in good yields (57-95%), which suffer quantitative intramolecular cyclocondensation to produce 1-alkyl(aryl)-5-(2-oxo-3,3,3-trihalopropylidene)pyrrolidin-2-ones 5, 6, are reported. The structures of the isolated new products were assigned by means of 1 H, 13 C NMR measurements and mass spectrometry. The Z and E configuration of compounds 3d and 5b respectively were established from X-ray crystallography.