The selective oxidation of sulfides to sulfoxides in the presence of a new hydrazoneSchiff base zinc(II) complex as catalyst

A new tridentate hydrazone Schiff base ligand of (E)-N'-([۱,۱'-biphenyl]-۴-ylmethylene)isonicotinohydrazide (۴-bpinh), was prepared by the condensation of isonicotinic acid hydrazidewith biphenyl-۴-carboxaldehyde. Then, its nano-sized and single crystal of zinc complex were synthesizedusing sonochemical and heat gradient methods, respectively. The structure of this complex [Zn(۴-bpinh)۲ Br۲]was determined by single-crystal X-ray diffraction, FT-IR, and elemental analysis, FT-IR, XRD, and SEMtechniques. The crystal structure analysis represent the presence of various intermolecular interactions suchas H···H, H···Br, H···N, H···O, H···C and C···C in assembling the molecules of Zn(۴-bpinh)۲Br۲ into a ۳Dsupramolecular network. The catalytic activity of Zn(۴-bpinh)۲Br۲ was studied in the chemoselective oxidationof sulfide derivatives to corresponding sulfoxides using hydrogen peroxide as the green oxidative agent.

Keywords:

Sonochemical synthesis , Schiff base hydrazone , sulfoxides , catalytic activities