화학공학소재연구정보센터
Inorganic Chemistry, Vol.42, No.3, 827-833, 2003
The effect of a 3-benzyl group on the coordination chemistry of homoscorpionate ligands
New homoscorpionate ligands containing a 3-benzyl substituent, hydrotris(3-benzyl-5-methylpyrazol-1-yl)borate, Tp(Bn,Me), and hydrotris(3-benzyl-4-phenylpyrazol-1-yl)borate, Tp(Bn,4Ph), have been synthesized, and the dynamic behavior of a number of metal complexes was studied by NMR. Structures of the complexes TI[Tp(Bn,Me)], 1, TI[Tp(Bn,4Ph)], 2, Co[Tp(Bn,Me)][Tp(Np)], 3, Mo[Tp(Bn.Me)](CO)(2)NO, 4, Co[Tp(Bn,4Ph)][Tp], 5, and Mo[Tp(Bn,Me)](CO)(2)(eta(3)-methallyl), 6, were determined by X-ray crystallography. In the Tp(Bn,Me) ligand, the benzyl group is freely rotating and provides less steric hindrance to the coordinated metal than a neopentyl group, but steric hindrance is increased in the Tp(Bn,4Ph) ligand, where the rotation of the benzyl substituent is restricted by the 4-phenyl substituent.