Titanium-47 and titanium-49 nuclear magnetic resonance in titanium(IV)-halogen compounds
Titanium-47 and titanium-49 nuclear magnetic resonance in titanium(IV)-halogen compounds
复制标题
钛(IV)-卤素化合物中的钛 47 和钛 49 核磁共振
DOI：
10.1021/ja00774a020
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发表时间：
1972
影响因子：
15
通讯作者：
H. Spinney
中科院分区：
文献类型：
--
作者：
R. G. Kidd;R. W. Matthews;H. Spinney
本文测定了TiCl_4、TiBr_4、TiF_（62）_3及TiCl_4-TiBr_4、TiCl_4-TiI_4二元混合物的~（47）Ti和~（49）Ti NMR谱的化学位移数据。卤素配体对钛核屏蔽作用的增强顺序为I，Br< Cl。TiCl_4和TiBr_4在惰性溶剂中稀释时，其共振峰不发生位移。这为纯液体中存在单体分子提供了证据。TiCl 4和TiBr 4的混合物只有一个共振信号，其化学位移与组分的摩尔分数呈线性关系，表明母体化合物与混合物种TiCl 3Br、TiCl 2Br 2和TiClBr 3之间发生了快速交换。近年来已经报道了四面体或假四面体含卤素环境中各种原子的NMR的广泛化学位移数据。显然，毫无例外地，所研究的原子核屏蔽增加的顺序是Cl< Br< I。特别是“B、1· 2 13 C、3~ 7 27 A1、S
Chemical shift data for the 47Ti and 49Ti nmr of TiCl4, TiBr4, and TiF62_, and binary mixtures of TiCl4-TiBr4, TiCl4-TiI4, have been determined. The order of increasing shielding of the titanium nucleus by the halogen ligands is I, Br< Cl. The resonance absorptions for TiCl4 and TiBr4 are unshifted on dilution of these compounds in inert solvents. This provides evidence for the existence of monomeric molecules in the neat liquids. The mix-ture of TiCl4 and TiBr4 showed just one resonance signal, the chemical shift of which varied linearly with the mole fraction of the components, indicating rapid exchange between the parent compounds and the mixed species TiCl3Br, TiCl2Br2, and TiClBr3. xtensive chemical shift data for the nmr of various atoms in tetrahedral or pseudo-tetrahedral halogen-containing environments have been reported in re-cent years. Apparently without exception, the order of increasing shielding of the nucleus under investigations is Cl< Br< I. In particular, the nuclei for which this trend has been found are“B, 1· 2 13C, 3~ 7 27A1, S