Síntese de 1-[aril(heteroaril)]-5-(3,3,3-trifluor-2-oxopropilideno) pirrolidin-2-onas

Abstract

The synthesis of a series of ten 1-[aryl(heteroaryl)]-5-(3,3,3-trifluoro-2-oxopropilideno) pyrrolidin-2-ones by intramolecular cyclocondensation reaction of methyl 7,7,7-trifluoro-4-[aryl(heteroaryl)amino]-6-oxo-4-heptanoates in excellent yields (69-95%) is reported. The methyl heptanoate intermediates were obtained in three sequential steps: (i) acetalization of 4-oxopentanoic acid with trimethyl orthoformate; (ii) acetylation of the acetal with trifluoroacetic anhydride; (iii) reaction of methyl 7,7,7-trifluoro-4-methoxy-6-oxo-4-heptanoate with primary amines [R NH2, where R = PhCH2, PhCH2CH2, Ph, 4-Me-C6H4, 4-MeO-C6H4, 4-Cl-C6H4, 4-Br-C6H4, 4-NH2-C6H4, pyrid-2-yl, isoxazol-2-yl) to obtain methyl 7,7,7-trifluoro-4-[aryl(heteroaryl)amino]-6-oxo-4-heptanoates in moderate to good yields (57 95%).