Mehring M, Guerrero G, Dahan F, Mutin P H, Vioux A
UMR CNRS 5637, Chimie Moléculaire et Organisation du Solide, Case 007, Université de Montpellier II, 34095 Montpellier, France.
Inorg Chem. 2000 Jul 24;39(15):3325-32. doi: 10.1021/ic000002k.
Reactions of Ti(OiPr)4 with different phosphonic acids RPO3H2 (R = Ph, 4-CNPh, Me, tBu) in organic solvents have been investigated. In the presence of small amounts of water, the new molecular titanium oxide alkoxide phosphonates [Ti4(mu 3-O)(OiPr)5(mu-OiPr)3(RPO3)3].DMSO [R = Ph (1), Me (2), tBu (3), 4-CNPh (4)] were isolated. The single-crystal X-ray structure analyses of 1 and 2 revealed hexacoordinated titanium atoms and a connectivity of (111) for each phosphonate. Under rigorous exclusion of water, the reaction of Ti(OiPr)4 with tert-butylphosphonic acid in toluene gave the titanium phosphonate tetramer [Ti(OiPr)2(tBuPO3)]4 (5). A single-crystal X-ray structure analysis of 5 revealed a 5 + 1 coordination of the titanium atoms as a result of the (112) connectivity of each phosphonate; such a coordination mode has never been reported for a titanium phosphate, phosphonate, or phosphinate. Compounds 1-5 were characterized by FT-IR, 31P MAS NMR, and solution multinuclear NMR (1H, 13C(1H,) 31P(1H)) spectroscopies. 13C CP MAS NMR experiments were carried out on arylphosphonates 1 and 4. Solution NMR experiments were also used to investigate the exchange reaction between 1 and 2 and the conversion of 5 to [Ti4(mu 3-O)(OiPr)5(mu-OiPr)3(tBuPO3)3].iPrOH by partial hydrolysis in the presence of Ti(OiPr)4. The phosphonate clusters 1-5 are soluble in organic solvents and are likely intermediates in the sol-gel processing of inorganic-organic hybrids based on titanium oxide and phosphonate groups that we are currently developing.
研究了四异丙醇钛（Ti(OiPr)4）与不同膦酸RPO3H2（R = 苯基、4-氰基苯基、甲基、叔丁基）在有机溶剂中的反应。在少量水存在下，分离得到了新型分子钛氧化物醇盐膦酸盐[Ti4(μ3 - O)(OiPr)5(μ - OiPr)3(RPO3)3].DMSO [R = 苯基 (1)、甲基 (2)、叔丁基 (3)、4-氰基苯基 (4)]。对1和2的单晶X射线结构分析表明，每个膦酸盐中的钛原子为六配位，连接性为(111)。在严格排除水的情况下，四异丙醇钛与叔丁基膦酸在甲苯中的反应生成了钛膦酸盐四聚体[Ti(OiPr)2(tBuPO3)]4 (5)。对5的单晶X射线结构分析表明，由于每个膦酸盐的(112)连接性，钛原子呈现5 + 1配位；这种配位模式在磷酸钛、膦酸盐或次膦酸盐中从未有过报道。通过傅里叶变换红外光谱（FT-IR）、31P 魔角旋转核磁共振（31P MAS NMR）和溶液多核核磁共振（1H、13C(1H)、31P(1H)）光谱对化合物1 - 5进行了表征。对芳基膦酸盐1和4进行了13C交叉极化魔角旋转核磁共振（13C CP MAS NMR）实验。溶液核磁共振实验还用于研究1和2之间的交换反应以及在四异丙醇钛存在下通过部分水解将5转化为[Ti4(μ3 - O)(OiPr)5(μ - OiPr)3(tBuPO3)3].异丙醇的过程。膦酸盐簇1 - 5可溶于有机溶剂，可能是我们目前正在开发的基于氧化钛和膦酸基团的无机 - 有机杂化材料溶胶 - 凝胶过程中的中间体。
