Lysenko, Andrey B. Senchyk, Ganna A. Domasevitch, Konstantin V. Kobalz, Merten Krautscheid, Harald Cichos, Jakub Karbowiak, Miroslaw Neves, Patrícia Valente, Anabela A. Gonçalves, Isabel S. Triazolyl, Imidazolyl, and Carboxylic Acid Moieties in the Design of Molybdenum Trioxide Hybrids: Photophysical and Catalytic Behavior Three organic ligands bearing 1,2,4-triazolyl donor moieties, (<i>S</i>)-4-(1-phenylpropyl)-1,2,4-triazole (<i>trethbz</i>), 4-(1,2,4-triazol-4-yl)­benzoic acid (<i>trPhCO</i><sub>2</sub><i>H</i>), and 3-(1<i>H</i>-imidazol-4-yl)-2-(1,2,4-triazol-4-yl)­propionic acid (<i>trhis</i>), were prepared to evaluate their coordination behavior in the development of molybdenum­(VI) oxide organic hybrids. Four compounds, [Mo<sub>2</sub>O<sub>6</sub>(<i>trethbz</i>)<sub>2</sub>]·H<sub>2</sub>O (<b>1</b>), [Mo<sub>4</sub>O<sub>12</sub>(<i>trPhCO</i><sub>2</sub><i>H</i>)<sub>2</sub>]·0.5H<sub>2</sub>O (<b>2a</b>), [Mo<sub>4</sub>O<sub>12</sub>(<i>trPhCO</i><sub>2</sub><i>H</i>)<sub>2</sub>]·H<sub>2</sub>O (<b>2b</b>), and [Mo<sub>8</sub>O<sub>25</sub>(<i>trhis</i>)<sub>2</sub>(<i>trhisH</i>)<sub>2</sub>]·2H<sub>2</sub>O (<b>3</b>), were synthesized and characterized. The monofunctional <i>tr</i>-ligand resulted in the formation of a zigzag chain [Mo<sub>2</sub>O<sub>6</sub>(<i>trethbz</i>)<sub>2</sub>] built up from <i>cis-</i>{MoO<sub>4</sub>N<sub>2</sub>} octahedra united through common μ<sub>2</sub>-O vertices. Employing the heterodonor ligand with <i>tr/–CO</i><sub>2</sub><i>H</i> functions afforded either layer or ribbon structures of corner- or edge-sharing {MoO<sub>5</sub>N} polyhedra (<b>2a</b> or <b>2b</b>) stapled by <i>tr</i>-links in axial positions, whereas −CO<sub>2</sub>H groups remained uncoordinated. The presence of the <i>im-</i>heterocycle as an extra function in <i>trhis</i> facilitated formation of zwitterionic molecules with a protonated imidazolium group (<i>imH</i><sup><i>+</i></sup>) and a negatively charged −CO<sub>2</sub><sup>–</sup> group, whereas the <i>tr-</i>fragment was left neutral. Under the acidic hydrothermal conditions used, the organic ligand binds to molybdenum atoms either through [N–N]-<i>tr</i> or through both [N–N]-<i>tr</i> and μ<sub>2</sub>-CO<sub>2</sub><sup>–</sup> units, which occur in protonated bidentate or zwitterionic tetradentate forms (<i>trhisH</i><sup><i>+</i></sup> and <i>trhis</i>, respectively). This leads to a new zigzag subtopological motif (<b>3</b>) of negatively charged polyoxomolybdate {Mo<sub>8</sub>O<sub>25</sub>}<sub><i>n</i></sub><sup>2<i>n</i>–</sup> consisting of corner- and edge-sharing <i>cis-</i>{MoO<sub>4</sub>N<sub>2</sub>} and {MoO<sub>6</sub>} octahedra, while the tetradentate zwitterrionic <i>trhis</i> species connect these chains into a 2D net. Electronic spectra of the compounds showed optical gaps consistent with semiconducting behavior. The compounds were investigated as epoxidation catalysts via the model reactions of achiral and prochiral olefins (<i>cis</i>-cyclooctene and <i>trans</i>-β-methylstyrene) with <i>tert</i>-butylhydroperoxide. The best-performing catalyst (<b>1</b>) was explored for the epoxidation of other olefins, including biomass-derived methyl oleate, methyl linoleate, and prochiral dl-limonene. ligand;compound;Molybdenum Trioxide Hybrids;protonated imidazolium group;acidic hydrothermal conditions;trPhCO 2 H;zigzag subtopological motif;zwitterionic tetradentate forms;μ 2;MoO 5 N;imidazol -4-yl acid;biomass-derived methyl oleate;trans -β- methylstyrene;tetradentate zwitterrionic trhis species;Mo 8 O 25;trethbz;Mo 4 O 12;MoO 4 N 2;Mo 2 O 6 2017-04-03
    https://acs.figshare.com/articles/dataset/Triazolyl_Imidazolyl_and_Carboxylic_Acid_Moieties_in_the_Design_of_Molybdenum_Trioxide_Hybrids_Photophysical_and_Catalytic_Behavior/4810978
10.1021/acs.inorgchem.6b02986.s002