Dinuclear oxidovanadium complexes with dihydrazone ligands derived from diethyl 2,6-dimethylpyridine-3,5-dicarboxylate obtained from Hantzsch reaction; crystal structure and catalytic activity

Two new dihydrazone ligands (H4L1 and H4L2) have been prepared from Hantzsch pyridine ester and after characterization by analytical methods, they have been used in the synthesis of oxidovanadium complexes through their reaction with NH4VO3 in methanol. The oxidovanadium complexes have been characterized by single crystal X-ray analysis, which revealed that both of them are anionic dinuclear complexes with the general formula of (NH4)(2)[(VO2)(2)L-1]center dot (CH3OH)(2)(H2O)(0.33) (1) and (NH4)(2)[(VO2)(2)L-2]center dot (H2O) (2). These complexes have been used in the oxidation of sulfides by H2O2 and the results showed that they can efficiently oxidize sulfides. Temperature, solvent and the ratio of oxidant to sulfide are effective parameters in the selective oxidation of sulfides by 1 and 2 and they can also influence the catalytic activity of these compounds.

Automated summary

Two new dihydrazone ligands were used to synthesize oxidovanadium complexes, which were characterized by single crystal X-ray analysis as anionic dinuclear complexes. These complexes showed efficient oxidation of sulfides, with temperature, solvent, and oxidant-to-sulfide ratio influencing the selective oxidation and catalytic activity.