| 474254-35-8

• CAS: 474254-35-8
• 化学式: C₂₄H₁₀Al₂F₅₀O₈Tl₂
• 分子量: 1838.99
• InChiKey: RTMYXXSAYCWBSG-UHFFFAOYSA-L

反应信息

• 作为产物：
  描述：

  thallium(I) fluoride 、 以 二氯甲烷 为溶剂， 以55%的产率得到
  参考文献：
  名称：

  A Thallium Coated Dianion: Trigonal Bipyramidal [F2Al(OR)3]2— Coordinated to Three Tl+ Cations in the Ion Pair [Tl3F2Al(OR)3]+[Al(OR)4]— [R = CH(CF3)2]Dedicated to Professor Dieter Naumann on the Occasion of his 60th Birthday

  摘要：

  The reproducible synthesis of the unusual ionic aluminum compound [Tl3F2Al(OR)(3)](+)[Al(OR)(4)](-) (1) is reported. In the reaction of Li[Al(OR)(4)] [R=C(H)(CF3)(2)] with TIF the initially desired Tl[Al(OR)(4)] only formed with an exact 1:1 stoichiometry, while an excess of TIF led to [Tl3F2Al(OR)(3)](+)[Al(OR)(4)](-) (1). Additionally the x-ray single crystal structure of the byproduct [(R-OH)TlAl-(OR)(3)(mu-F)](2) (2) was determined. Compounds 1 and 2 were characterized by X-ray single crystal structure determinations and 1 also by NMR spectroscopy and an elemental analysis. In 1 the [Tl3F2Al(OR)(3)](+) cation forms a trigonal bipyramid with a pentacoordinate aluminum atom. Three Tl+ cations cover the [F2Al(OR)(3)](2-) dianion core and the charge of the resulting [Tl3F2Al(OR)(3)](+) cation is compensated by a weakly coordinating [Al(OR)(4)](-) anion. Compound 2 contains a centrosymmetric [Al(OR)(3)(mu-F)](2)(2-) dianion core with pentacoordinate aluminum atoms building a distorted edge sharing double trigonal bipyramid. The [Al(OR)(3)(mu-F)](2)(2-) dianion coordinates two [Tl(R-OH)](+) cations giving the non charged molecular [(R-OH)TlAl(OR)(3)(mu-F)](2) (2). Based on BP86/SVP (DFT-) and lattice enthalpy calculations a pathway of the reaction was proposed to rationalize the formation of the [M3F2Al(OR)(3)](+) cation upon reaction of Li[Al(OR)(4)] with MF for M=Tl but not for M=Cs (cf. Cs+ and Tl+ have very similar ionic radii). Using a suitable Born-Haber cycle and in agreement with the experiment, the enthalpies of the reaction of 2 M[Al(OR)(4)] with 2 MF giving [M3F2Al(OR)(3)](+)[Al(OR)(4)](-) and MOR were shown to be favorable for M=Tl by 127 kJ/mol but endothermic for the formation of the hypothetical [Cs3F2Al(OR)(3)](+)[Al(OR)(4)](-) by 95 kJ/mol. It is suggested that in the reaction leading to 1 initially Tl[Al(OR)(4)] is formed, followed by an abstraction of TlOR and Al(OR)(3). The latter very strong Lewis acid reacts subsequently with an excess of TlF yielding 1.

  DOI：

  10.1002/1521-3749(200208)628:8<1821::aid-zaac1821>3.0.co;2-3