The ligands [hydrotris(3-cyclohexylpyrazol-1-yl)borate, [Tp(Cy)](-), tetrakis(3-cyclohexylpyrazol-1-yl) borate, [pzdegreesTp(Cy)](-), and hydrotris(3-cyclohexyl-4-bromopyrazol-1-yl)borate, [Tp(Cy),(4Br)](-) were synthesized and characterized as their Tl(l) derivatives. They were converted to a variety of tetrahedral LMX and octahedral LML' complexes, as well as to the dinuclear nickel carbonate complex [NI(Tp(Cy))](2)(CO3), 4, and the compound Ni[Tp(Cy,4Br)][pz(Cy,4Br)](3)(H)(2), 5. The structures of Co[Tp(Cy)]Cl, 1, Co[Tp(Cy,4Br)]Cl, 2, Co[Tp(Cy,4Br)]NCS, 3, [Ni(Tp(Cy))](2)(CO3), 4, Ni[Tp(Cy),(4Br)][pz(Cy,4Br)](3)(H)(2), 5, and Mo[Tp(Cy)]-(CO)(2)(eta(3)-methallyl), 6, were determined by X-ray crystallography. The structures of paramagnetic heteroleptic complexes Co[Tp(Cy)][Tp], Co[Tp(Cy)][Tp*], Co[Tp(Cy,4Br)][Tp], and Co[Tp(Cy,4Br)[Tp*] were established by NMR. The homoleptic compounds Co[Tp(Cy)](2) and Co[Tp(Cy,4Br)](2) rearrange thermally to Co[Tp(Cy)*](2) and to Co[Tp((Cy,4Br)*)](2), respectively, containing one 5-cyclohexyl group/ligand.