The two new pyrazole-based dinucleating ligands 3,5-bis(fluoren-9-ylmethyl)-1H-pyrazole (H 3 L a ) and 3,5-bis(inden-3-ylmethyl)-1H-pyrazole (H 3 L b ) have been prepared and structurally characterized in the case of H 3 L a , and their lithium complexes Li 3 L a and Li 3 L b are reported. These systems can be viewed as coupled dinucleating versions of two widely used Cp fragments bearing pendant amino or amido side chains, which is confirmed by the crystal structure of the solvent-separated ion pair [Li 2 L a (thf) 4 ][Li(thf) 4 ]. In solution, 7 Li NMR spectroscopy indicates the predominant presence of contact ion pairs. The crystal structure of the partially lithiated compound [Li 2 HL a (thf) 5 ] is also presented.
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