Dai Lin-Fang, Liu Xue-Ru, Tian Yi-Qi, Yi Xiao-Yi, Liu Chao
College of Chemistry and Chemical Engineering, Central South University, Changsha 410083, Hunan, P. R. China.
College of Chemistry and Materials Science, Northwest University, Xi'an 710127, P. R. China.
Inorg Chem. 2023 Apr 17;62(15):6047-6054. doi: 10.1021/acs.inorgchem.2c04528. Epub 2023 Apr 5.
This study used the -butylcalix[6]arene (TBC[6]) as the ligand and successfully synthesized six TBC[6]-stabilized titanium-oxo clusters (TOCs) by the one-step solvothermal reaction. These six compounds were [TiO(TBC[6])] (), {Ti(TBC[6])(EtO)(SaH)} (, HSa = squaric acid), {Ti(TBC[6])(EtO)(Oa)} (, HOa = oxalic acid), [HTi(TBC[6])(BA)(EtO)] (, HBA = benzoic acid), [TiO(TBC[6])(BA)(OPr)] (), and [Ti(TBC[6])(Sal)(EtO)] (, HSal = salicylic acid). These clusters contain one or two TBC[6] ligands, with the biconical or monoconical configuration, greatly increasing the variety of TOCs it could support. The introduction of auxiliary carboxylic ligands can further stimulate the growth of structures, with the cluster core gradually increased from {Ti-TBC[6]-Ti} to {Ti-TBC[6]-Ti}, to {Ti-TBC[6]-Ti}, and finally to {Ti-TBC[6]-Ti-TBC[6]-Ti} with 3.1 nm length. Structural regulation may affect their solution stability, absorption spectra, and photocurrent response. The study of catalytic activities shows that these clusters can be used as recyclable heterogeneous photocatalysts for the oxidation of sulfide to sulfoxide. The catalytic efficiency of the TBC[6]-Ti system is closely related to the cluster structure, and the exposure of the Ti site on the catalyst surface can significantly enhance the catalytic activity of the clusters.
本研究以对叔丁基杯[6]芳烃（TBC[6]）为配体，通过一步溶剂热反应成功合成了六种TBC[6]稳定的钛氧簇（TOC）。这六种化合物分别为[TiO(TBC[6])]（）、{Ti(TBC[6])(EtO)(SaH)}（，HSa = 方酸）、{Ti(TBC[6])(EtO)(Oa)}（，HOa = 草酸）、[HTi(TBC[6])(BA)(EtO)]（，HBA = 苯甲酸）、[TiO(TBC[6])(BA)(OPr)]（）和[Ti(TBC[6])(Sal)(EtO)]（，HSal = 水杨酸）。这些簇包含一个或两个具有双锥或单锥构型的TBC[6]配体，极大地增加了其所能支持的TOC种类。辅助羧酸配体的引入可进一步促进结构的生长，簇核从{Ti-TBC[6]-Ti}逐渐增加到{Ti-TBC[6]-Ti}，再到{Ti-TBC[6]-Ti}，最终到长度为3.1 nm的{Ti-TBC[6]-Ti-TBC[6]-Ti}。结构调控可能会影响它们在溶液中的稳定性、吸收光谱和光电流响应。催化活性研究表明，这些簇可作为可循环使用的多相光催化剂用于将硫化物氧化为亚砜。TBC[6]-Ti体系的催化效率与簇结构密切相关，催化剂表面Ti位点的暴露可显著增强簇的催化活性。
