Dihydroxycoumarin Schiff base synthesis and structure determination from powder diffraction data

The titled compound with systematic name 4-hydroxy-3-((E)-1-(2-((E)-1-(4-hydroxy-2-oxo-2H-chromen-3-yl)ethylideneamino)ethylimino) ethyl)-2H-chromene-2-one is a new tetradentate (ONNO) Schiff-base which was synthesized by condensation of ethylenediamine and 3-acethyl 4-hydroxycoumarin. Its crystal structure was ab initio determined from laboratory X-ray powder diffraction data by using the direct space approach. The structure is monoclinic with space group P21/n and unit cell parameters a = 10.4153(4) Å, b = 12.8319(4) Å, c = 7.48229(15) Å, β = 98.892(3) Å, V = 987.97(5) Å3. The asymmetric part of the structure contains one half of the centrosymmetric molecule. The obtained product was also characterized by infrared, UV–VIS and 1H NMR spectroscopy.