Terephthalate and N-Oxide Isonicotinate Complexes of the {MoI} Cluster

The reaction of (TBA)[MoI(OAc)] with terephthalic acid and isonicotinic acid N-oxide afforded new complexes, (TBA)[MoI(ООС–CH–COOH)](I) and (TBA)[MoI(ООС– CHNO)] (II), respectively. The optimized synthesis of complex II involves microwave activation of the reaction mixture at 130°C in a Teflon reactor of the ETHOS UP Milestone microwave setup. According to X-ray diffraction data, the molybdenum atoms in the cluster cores of I and II are monodentately coordinated by carboxylate ligands. The cluster anions of complex I [MoI(ООС–CH–COOH)] are combined into a three-dimensional structure, the crystal structure contains solvate molecules. Samples of complexes I and II were characterized by elemental analysis for C, H, N, IR spectroscopy, electrospray mass spectrometry and proton magnetic resonance. For powder samples of I and II, bright phosphorescence with emission maxima at ~680 nm, φ = 15%, τ = 125 μs (I) and φ = 12%, τ = 137 μs (II) (in air at λ = 440 nm) was revealed.