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Hydrothermal Synthesis and Structure of a Dinuclear Molybdenum(III) Hydroxy Squarate with a Mo-Mo Bond.

ABSTRACT: The reaction of molybdenum(II) and chromium(II) acetates with squaric acid in degassed and deionized water under hydrothermal conditions at 150 °C is described. The products have been formulated as M2(?-OH)2(?-C4O4)2(H2O)4·2H2O, where M = Cr (1) and Mo (2), based on combustion elemental analysis, infrared spectroscopy, magic angle spinning (MAS) solid-state carbon-13 nuclear magnetic resonance (NMR), and single-crystal X-ray diffraction. The edge-shared bioctahedral structures involve doubly bridging hydroxide ligands and ?-squarate ligands. The chromium compound lacks a direct metal-metal-bonding interaction, while in contrast the molybdenum compound contains a Mo-Mo bond [2.491(2) Å]. The nature of the Mo-Mo-bonding interaction is compared with that of other similar d3-d3 dimers.

SUBMITTER: Barber GD

PROVIDER: S-EPMC7066654 | biostudies-literature | 2020 Mar

REPOSITORIES: biostudies-literature

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Hydrothermal Synthesis and Structure of a Dinuclear Molybdenum(III) Hydroxy Squarate with a Mo-Mo Bond.

Barber Greg D GD George Christy C Hogg Kathryn K Johnstone Shae T ST Pacheco Carlos N CN Yennawar Hemant P HP Van Der Sluys William G WG

ACS omega 20200228 9

The reaction of molybdenum(II) and chromium(II) acetates with squaric acid in degassed and deionized water under hydrothermal conditions at 150 °C is described. The products have been formulated as M2(μ-OH)2(μ-C4O4)2(H2O)4·2H2O, where M = Cr (1) and Mo (2), based on combustion elemental analysis, infrared spectroscopy, magic angle spinning (MAS) solid-state carbon-13 nuclear magnetic resonance ( ...[more]

PMID: 32175513

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