Synthesis and Structure of the Acylhydrazone Schiff Base

T Salicylaldehyde-2-(4-isobutylphenyl)-propionyl hydrazone Schiff base(H2L)has been synthesized and characterized by elemental analysis,IR,1H-NMR spectrum and single-crystal X-ray diffraction.Single-crystal X-ray diffraction analysis showed that H2L is of monoclinic system,space group P21/c with α=5.6844(5),b=33.568(3),c=9.6959(9)(A),β=91.758(2)°,V=1849.2(3)(A)3,Mr=324.41,F(000)=696,Z=4,Dc=1.165 g/cm3,/2=0.076 mm-1,R=0.0448 and wR=0.1221.In the solid form,the strong intramolecular hydrogen bonds make H2L fully extended into an E isomer about the N=N bond,and each molecule interacts with two neighbors to form 1D hydrogen-bonded chains.The Schiff base presents two different sets of signals in the 1H-NMR and 13C-NMR spectra in either chloroform or dimethylsulfoxide solution,showing the presence of both E and Z isomers.