Tbf lithium

These results raise the question whether Tbf lithium also forms separated ion pairs in the solid state when other coordinating solvents such as dime-thoxyethane (DME) are used. Therefore, Tbf lithium was prepared by deprotonation of TbfH by n-butyUithium in toluene. The white precipitate was hltered and redissolved in DME (Scheme 6.6). Cooling the resulting yellow solution to -80 °C yields blocky yellow crystals (melting point 98 °C), suitable for X-ray diffraction. Like V TbfLi(DME)3 (VI) crystallizes in space group P-1, the triclinic unit cell contains 0.25equiv of DME in addition to four separated ion pairs of VI (Fig. 6.3). Like in the case of V, also for VI, two symmetry independent molecules are found in the unit cell. However, the structural data are identical with respect to the standard deviation for that reason, only one molecule is discussed. 

Treatment of the 9-fluoro-l,4-dien-3-ol (15) with 3.5 g-atoms of lithium and l-methoxy-2-propanol in ammonia reductively cleaves the allylic 3-hy-droxyl group to give tbf corresponding 3-desoxy compound, but the fluorine... 

As depicted in Scheme 6.13, compound IX was reacted with lithium phenoxides in a toluene slurry to form an array of Tbf titanium monophenoxides of the general formula TbfIlCl20Ar. Generally, working up the reaction... 

The efficient syntheses of IVa allows an effective access to the organometallic chemistry of the Tbf moieties. Using the remarkable r -coordinated lithium salts y and VI, monosubstituted titanium(IV) alkoxides and aryloxides become available. The Tbf moiety is coordinated as a sterically demanding Cp derivative in an ii fashion to the titanium centers. The formal benzannula-tion of the fluorenyl system, as present in the Tbf titanium complexes, leads to large mono Cp complexes of high thermal stability compared to ii -fluorenyl titanium derivatives. Due to its heUcal twist, the T -coordinated Tbf ligands show Cl symmetry in the solid state but seem to interconverse in solution. Additionally, the titanium complexes were subjected to polymerization experiments of styrene to some extent. 

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