Synthesis and crystal structure of novel mononuclear Mo(IV) and Mo(III) complexes containing bis(3,5-dimethylpyrazol-1-yl)acetate anion as ligand

Reaction of bis(3,5-dimethylpyrazol-1-yl)acetic acid (Hbdmpza) with [MoCl4(Ac)2], in acetonitrile (Ac) at room temperature results in obtaining [Mo(IV)Cl3(bdmpza)]∙Ac (1) (Ac = acetonitrile). The treatment of 1 in pyridine (py) gives pyH[Mo(III)Cl3(bdmpza)]∙2py (2) (py = pyridine. The complexes were characterized by X-ray structure analysis, UV-visible and IR spectroscopy. The coordination spheres in the molecule [MoCl3(bdmpza)] and in the anion [MoCl3(bdmpza)]– are the same. Both species exhibit a six-coordinate distorted octahedral geometry. They differ only in the oxidation state of the central molybdenum ion.

Graphical AbstractTwo novel mononuclear neutral octahedral Mo(IV) and Mo(III) complexes have been prepared. The reaction of [MoCl4(CH3CN)2] with tripod heteroscorpionate N,N,O-ligand (Hbdmpza) results in [MoIVCl3(bdmpza)] (1). By reduction with pyridine 1 changes into [MoIIICl3(bdmpza)]– (2).Figure optionsDownload full-size imageDownload as PowerPoint slideResearch Highlights► Synthesis of Mo(IV) and Mo(III) complexes with N,N,O-scorpionate ligand Hbdmpza. ► Complexes: [MoCl3(bdmpza)] ∙ CH3CN and pyH[MoCl3(bdmpza)]∙2py. ► X-ray crystal structure analysis, IR and UV-Vis spectra of complexes