Spectroscopic and thermal studies of chromium(III), molybdenum(VI) and ruthenium(0) complexes of maleic hydrazide

Interaction of maleic hydrazide (LH2) with [Cr(CO)6] in air at atmospheric pressure resulted in the formation of the complex [(LH)Cr(μ-O)2Cr(LH)] (1). Reaction of LH2 with [Mo(CO)6] in air also gave the complex [(LH2)O2Mo(μ-O)2MoO2(LH2)] (2). Under the same conditions, the reaction of LH2 with [Ru3(CO)12] resulted in the formation of the tricarbonyl complex [Ru(CO)3(LH2)] (3). The complexes were characterized by elemental analysis, IR, and 1H NMR spectroscopy. The thermal properties of the complexes were investigated by thermogravimetry technique.