N-(3-aminopropil) piperidina como precursora na síntese de 1,3-tiazolidin-4-onas.

Abstract

A systematic series of thirteen unpublished thiazolidinones were synthesized through cyclocondensation reaction between N-(3-aminopropyl)piperidine, substituted arenaldehydes (2-F, 3-F, 4-F, 2-Cl, 3-Cl, 4-Cl, 2-NO2, 3-NO2, 4-NO2, 2-OCH3, 3-OCH3, 4-OCH3, 4-CH3) and the mercaptoacetic acid. The stequiometric relationship of reactants was 1 equivalent of amine, 1 equivalent of aldehyde and 3 equivalent of mercaptoacetic acid. These 1,3-thiazolidin-4-ones were synthesized by multicomponent one-pot metodology using conventional termal heating in a Dean-Stark trap for azeotropic removal of water. First occurred the addition of amine with the arenealdehyde to afford the imine intermediate in situ for 2 hours of reaction. After that, the mercaptoacetic acid was added and the reaction was carried out over 3 hours more to occur the intramolecular cyclization to formation of products, in a 5 hours total reaction time. If necessary the compounds were purified by column chromatography with a mixture of hexane/ethyl acetate 8:2 as the eluent. The yields of the isolated products were in the range of 47-82%. All compounds are novel in the literature and were identified by gas chromatography coupled with mass spectrometry (GC-MS) and 1H and 13C nuclear magnetic resonance (NMR) in the 200/500 MHz spectrometer in CDCl3.