Synthesis and Characterization of Tbf Lithium

The crystals obtained are suitable for X-ray structure analysis V crystallizes in space group P-1 the triclinic unit cell contains four separated ion pairs. As to be seen in the ORTEP plot (Fig. 6.2), the tetrabenzo[a,c,g,i]fluorenide anion is not planar but exhibits a slightly helical distortion due to the steric repulsion of the aromatic ring protons. 

The tetrabenzoliuorenid complexes V and VI represent rare examples of T °-coordinated carbanions employing simple Lewis bases, like THF or DME, instead of crown ethers for coordinative saturation of the cation. 

NMR experiments were performed on VI in order to inspect if the compound also exists as separated ion pairs in solution, especially in nonpolar 

TABLE 6.1 Selected H (ppm, CtDe, 500.13MHz, 300 K) NMR Data of Compounds V and VI 

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