Iron, copper, and cobalt complexes of hydrotris(3-phenylpyrazolyl)borate and dihydrobis(3-phenylpyrazolyl)borate. Synthesis and X-ray crystallographic characterization

The scorpionate ligands containing 3-phenylpyrazole have been identified as possessing intermediate steric bulk, due to the wide range of structural types that have been characterized in complexes of these ligands. In this paper, we report the syntheses and structures of a number of complexes containing hydrotris(3-phenylpyrazol-1-yl)borate and dihydrobis(3-phenylpyrazolyl)borate which further manifest the versatility of these ligands. The syntheses and solid-state structures of Tp(Ph)Fe(SCN)(THF) (I), Tp(Ph) Fe(NO3)(2) (II), Tp(Ph)CuCl(pz(Ph)) (III), Tp(Ph)Cu(SCN)(pz(Ph)) (IV), Bp(2)(Ph) Co (V), and Tp(Ph)Bp(Ph)Co (VI) are reported (Tp(Ph) = hydrotris(3-phenylpyrazolylborate); Bp(Ph) = dihydrobis(3-phenylpyrazolylborate); pz(Ph) = 3-phenylpyrazole). Compound I displays a trigonal bipyramidal coordination sphere, while III and IV are square-pyramidal. Compound H contains one monodentate and one bidentate nitrate ligand in a distorted octahedral coordination sphere. Compound V is tetrahedral and VI is octahedral with an agostic Co-H interaction in the sixth coordination site. (C) 2001 Elsevier Science Ltd. All rights reserved.