ic0c00118_si_001.pdf (1.45 MB)
Gas Adsorption of Mixed-Valence Trinuclear Oxothiomolybdenum Glycolates
journal contribution
posted on 2020-03-18, 19:33 authored by Lan Deng, Xing Dong, Dong-Li An, Wei-Zheng Weng, Zhao-Hui ZhouTrinuclear oxothiomolybdenum(IV)
glycolates (H2glyc, glycolic acid) with 2-methylimidazole
(2-mim), 4-methylimidazole (4-mim), and sulfite, Na2[MoIV3(μ3-S)(μ2-O)3(glyc)3(2-mim)3]·1.5H2O (1), (4-Hmim)6[MoIV3(μ3-S)(μ2-O)3(glyc)3(4-mim)3]2[MoVIO2(glyc)2] (2), and Na3(4-Hmim)[MoIV3(μ3-S)(μ2-O)3(SO3)(glyc)3(4-mim)]·8H2O (3), have been isolated in reduced media, where 4-methylimidazole
trinuclear oxothiomolybdenum(IV) glycolates in 2 coprecipitate
with dioxomolybdenum(VI) glycolate, exhibiting unusual mixed valences
of 4+ and 6+. Large downfield shifts of glycolates have been observed
in solid-state and solution 13C (1H) NMR spectra
with coordination to Mo, indicating obvious dissociation of soluble 1 and 3 in solution. Investigations of the coordination
modes and conversions among the three complexes give insight into
the reactivities of trinuclear oxothiomolybdenum(IV) complexes. Channels
with 3.1 × 7.0 Å2 diameters exist in 2, showing reversible O2 absorption of 65.03 mg at 29.9
bar compared with little or no adsorption of N2, H2, CO2, and CH4 at room temperature,
respectively. Moreover, trinuclear 2- or 4-methylimidazole oxothiomolybdenum(IV)
glycolates 1 and 3 show only a few adsorptions
for O2 under the same conditions.
