Oppenheim Julius J, Bagi Sujay, Chen Tianyang, Sun Chenyue, Yang Luming, Müller Peter, Román-Leshkov Yuriy, Dincă Mircea
Inorg Chem. 2021 Dec 6;60(23):18205-18210. doi: 10.1021/acs.inorgchem.1c02850. Epub 2021 Nov 23.
We report the isolation of vanadium(II) in a metal-organic framework (MOF) by the reaction of the chloride-capped secondary building unit in the all-vanadium(III) V-MIL-101 () with 1,4-bis(trimethylsilyl)-2,3,5,6-tetramethyl-1,4-dihydropyrazine. The reduced material, , has a secondary building unit with the formal composition [VV], with each metal ion presenting one open coordination site. Subsequent reaction with O yields a side-on η vanadium-superoxo species, . The MOF featuring V(III)-superoxo moieties exhibits a mild enhancement in the isosteric enthalpy of adsorption for methane compared to the parent V-MIL-101. We present this synthetic methodology as a potentially broad way to access low-valent open metal sites within MOFs without causing a loss of crystallinity or porosity. The low-valent sites can serve as isolable intermediates to access species otherwise inaccessible by direct synthesis.
我们报道了通过全钒（III）V-MIL-101（ ）中氯化物封端的二级构筑单元与1,4-双（三甲基硅基）-2,3,5,6-四甲基-1,4-二氢吡嗪反应，在金属有机框架（MOF）中分离出钒（II）。还原后的材料 具有形式组成为[VV]的二级构筑单元，每个金属离子都有一个开放的配位位点。随后与O反应生成侧基η钒-超氧物种 。与母体V-MIL-101相比，具有V（III）-超氧部分的MOF对甲烷的吸附等量焓略有增强。我们提出这种合成方法是一种潜在的广泛途径，可用于在MOF中获得低价开放金属位点，而不会导致结晶度或孔隙率的损失。低价位点可作为可分离的中间体，以获得通过直接合成无法获得的物种。
