The new organic ligand: 3-(5-Carboxy-2-chlorophenylaminomethylene)-2-methoxychroman-4-one. Structural, spectral and thermal aspects

The new organic ligand, 3-(5-carboxy-2-chlorophenylaminomethylene)-2-methoxychroman-4-one was synthesized. The crystal structure, FTIR, UV–VIS and 1H NMR spectra, and thermal stability of this chromanone have been analysed. It is the first X-ray structure determination of 3-(5-carboxy-2-chlorophenylaminomethylene)-2-methoxychroman-4-one. It has been found that reaction between 3-formylchromone and 3-amino-4-chlorobenzoic acid allows to obtain derivative of 4-chromanone by the mechanism of nucleophilic addition, accompanied by the opening of the pyrone ring. The FTIR spectra and X-ray analysis showed the presence of methoxy-group and intramolecular and intermolecular hydrogen bonds. According to the thermal investigation this compound is stable up to 128 °C in air atmosphere, above this temperature the ligand decomposes. This chromanone may be used as precursor to synthesis metal chelates.