Main Group Pyrazolates—the X-Ray Structures of [Al( η 2 -Bu t 2 pz) 3 ], [SnMe 3 ( η 1 -Ph 2 pz)] and [GePh

From metathesis reactions between AlCl3, SnMe3Cl, or GePh3Br and the appropriate potassium 3,5-disubstituted pyrazolate [K(R2pz)] the complexes [Al(Bu t2pz)3], [SnMe3(Ph2pz)], [SnMe3(Bu t2pz)], and [GePh3(Bu t2pz)] have been obtained. The X-ray structure of [Al(Bu t2pz)3] shows the complex to be monomeric with ? 2 -pyrazolate groups, in a quasi-trigonal prismatic array: the first monomeric homoleptic tris(pyrazolato) complex of any element. X-Ray structures of [SnMe3(Ph2pz)] and [GePh3(Bu t2pz)] reveal mononuclear species with distorted tetrahedral stereochemistries and ? 1 -pyrazolate groups. Comparisons of spectroscopic data between [SnMe3(Ph2pz)] and [SnMe3(Bu t2pz)] suggest the latter is also four-coordinate with an ? 1 -Bu t2pz ligand.