Two new “onium” fluorosilicates, the products of interaction of fluorosilicic acid with 12-membered macrocycles: structures and spectroscopic properties
作者:Vladimir O. Gelmboldt、Eduard V. Ganin、Marina S. Fonari、Yurii A. Simonov、Larisa V. Koroeva、Alim A. Ennan、Stepan S. Basok、Sergiu Shova、Hanspeter Kählig、Vladimir B. Arion、Bernhard K. Keppler
DOI:10.1039/b703645k
日期:——
Two novel compounds, (L1H)2[SiF6]·2H2O (1) and (L2H)2[SiF5(H2O)]2·3H2O (2), resulting from the reactions of H2SiF6 with 4â²-aminobenzo-12-crown-4 (L1) and monoaza-12-crown-4 (L2), respectively, were studied by X-ray diffraction and characterised by IR and 19F NMR spectroscopic methods. Both complexes have ionic structures due to the proton transfer from the fluorosilicic acid to the primary amine group in L1 and secondary amine group incorporated into the macrocycle L2. The structure of 1 is composed of [SiF6]2â centrosymmetric anions, N-protonated cations (L1H)+, and two water molecules, all components being bound in the layer through a system of NHâ¯F, NHâ¯O and OHâ¯F hydrogen bonds. The [SiF6]2â anions and water molecules are assembled into inorganic negatively-charged layers via OHâ¯F hydrogen bonds. The structure of 2 is a rare example of stabilisation of the complex anion [SiF5(H2O)]â, the labile product of hydrolytic transformations of the [SiF6]2â anion in an aqueous solution. The components of 2, i.e., [SiF5(H2O)]â, (L2H)+, and water molecules, are linked by a system of NHâ¯F, NHâ¯O, OHâ¯F, OHâ¯O hydrogen bonds. In a way similar to 1, the [SiF5(H2O)]â anions and water molecules in 2 are combined into an inorganic negatively-charged layer through OHâ¯F and OHâ¯O interactions.
两种新化合物,(L1H)2[SiF6]·2H2O (1) 和 (L2H)2[SiF5(H2O)]2·3H2O (2),由 H2SiF6 与 4â²-氨基苯并-12- 反应产生分别通过 X 射线衍射研究了 Crown-4 (L1) 和 monoaza-12-crown-4 (L2),并通过红外和 19F NMR 光谱方法进行了表征。由于质子从氟硅酸转移到L1中的伯胺基和并入大环L2中的仲胺基,两种配合物都具有离子结构。 1的结构由[SiF6]2-中心对称阴离子、N-质子化阳离子(L1H)+和两个水分子组成,所有组分通过NH-F、NH-O系统结合在层中和 OH−F 氢键。 [SiF6]2-阴离子和水分子通过OH-F氢键组装成带负电的无机层。 2 的结构是稳定复杂阴离子 [SiF5(H2O)]– 的罕见例子,该阴离子是 [SiF6]2– 阴离子在水溶液中水解转化的不稳定产物。 2 的组成部分,即 [SiF5(H2O)]−、(L2H)+ 和水分子,通过 NH−F、NH−O、OH−F、OH− 系统连接O氢键。与1类似,2中的[SiF5(H2O)]-阴离子和水分子通过OH-F和OH-O相互作用结合成无机负电荷层。