Treatment of the potassium salts of the Tp(x) ligands hydrotris(5-methyl-3-py*-pyrazolyl)borate Tp(3Py,Me) (py* = 3-pyridyl) and Tp(Pic,Me) (py* 5-alpha-picolyl) with zinc halides or with Zn(ClO4)(2) and KOH yields the halide complexes Tp(3Py,Me)Zn-Hal (Hal = F, Cl, Br, I) and the hydroxide complexes Tp(3Py,Me)Zn-OH and Tp(Pic,Me)Zn-OH, as well as the bis(ligand) complex (Tp(3Py,Me))(2)Zn. AU Tp(3Py,Me)Zn-X complexes show a tendency for dimerization, using one pyridyl group each of the two Tp(3Py,Me) units to coordinate to the zinc ion of the opposite Tp(3Py,Me)Zn fragment, as evidenced by the solid state structures of Tp(3Py,Me)Zn-F (strong interaction) and Tp(3Py,Me) Zn-I (weak interaction) and by a variable-temperature NMR. study of Tp(3Py,Me)Zn-OH. Despite the steric bulk of the Tp(3Py,Me) ligands, the his(ligand) complex (Tp(3Py,Me))(2)Zn contains zinc bound to all pyrazole nitrogen donor atoms in an octahedral fashion. Tp(3Py,Me)Zn-F crystallizes in the triclinic space group with a = 11.123(5) Angstrom, b = 11.638(7) Angstrom, c = 13.793(4) Angstrom, alpha = 72.34(3)degrees, beta = 75.32(3)degrees, gamma = 73.09(5)degrees, and Z = 2. Tp(3py,Me)Zn-I crystallizes in the monoclinic space group C2/c with a = 18.922(1) Angstrom, b = 10.476(4) Angstrom, c = 31.444(1) Angstrom, beta = 101.99(4)degrees, and Z = 8. (Tp(3Py,Me))(2)Zn crystallizes in the monoclinic space group C2/c with a = 18.330(2) Angstrom, b = 13.876(1) Angstrom, c = 21.616(1) Angstrom, beta = 115.96(7)degrees, and Z = 4.