Fluoro bridges

Caulton and coworkers found that fluoride ligands in certain Ir complexes promote oxidative addition reactions [44]. This group s results showed that the fluoride complex lr(H)2F(P Bu2Ph)2 rapidly activated C—H bonds under dehydrogenation conditions. The reactive intermediate in these reactions may be a fluoro-bridged analogue of compounds 4-12, namely [lr(p-F)(P Bu2Ph)2]2. This would explain the improved reactivity in the Ir-catalyzed OHA reaction in the presence of cocatalytic naked fluoride . 

The structure of the polymeric complex [U02F2(Me2S0)] consists of zigzag chains of uranium atoms linked by di-fi-fluoro bridges the coordination geometry about each uranium... 

The NiSn is deposited from a nickel(II) chloride-tin(II) chloride bath containing NH4HF2 since the metals are deposited in an accurate 1 1 ratio the involvement of a species such as NiSnF4 has been suggested. It has also been proposed that fluoro-bridged complexes are present and the possibility of trichloro- or trifluoro-stannate(II) complexes has been considered, X3Sn- Nin. A laser Raman study of the solution failed to reveal evidence of species other than aquonickel(II) species and fluorotin(II) species.38... 

A novel fluoro-bridged complex, pentafluoro-l,4-disilacyclohexane anion (206), was reported to undergo unusual intramolecular fluoride ion exchange between two silicon atoms, synchronized with a ring inversion process235. 

The tetramer Cp6 Yb4(/r-F)4 consists of two Cp2 Yb(/r-F)YbCp units centrosymmet-rically related and connected through fluoro bridges [151]. In the complex Yb111 is tetrahedral and Yb11 is trigonal as shown in Fig. 6.13. 

The yellow-green 0s02F3, made by reaction of a 1 1 mixture of 0s04 with OsF6 at 750 °C, is probably a tetramer or an infinite chain structure with single fluoro bridges.524... 

The X-ray crystal structure of the solid shows it to be tetrameric in the solid state with a structure closely akin to that of [RuF5]4, the metal atoms lying at the comers of a rhombus and linked by cis fluoro bridges (Os—F (bridge) = 2.03 A, mean Os—F(bridge)—Os angle = 137°). The mean Os —F terminal distance is 1,84 A (Figure 36). 

Structural Studies of Salts of Cis and Trans -Fluoro-Bridged Polymers of GeFs and of the GeFs Monomer... 

T. E. Mallouk, B. Desbat and N. Bartlett, Structural Studies of Salts of Cis and Trans //-Fluoro-Bridged Polymers of GeF and of GeFg Monomer, J. Inorg. Chem. 23 (1984) 3160-3166. 

The /X3-fluoro bridged cubane cores in molecules such as [Ni4(F)4(5-methylpyrazole)i2](BF4)4 show weak antiferromagnetic coupling and a corresponding maximum in x at 9 K 231). 

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