Sodium tri(pyrazol-1-yl)-germanate and -stannate: new tridentate ‘claw-ligands’ containing group 14 metals

Abstract

[(thf)₃Na{(pz)₃Ge}]1 and [(thf)₂(pzH)Na{(pz)₃Sn}]₂2(pz = pyrazol-1-yl) are obtained by the reaction of pzNa with GeCl₂·dioxane and SnCl₂, respectively, in a 3 : 1 molar ratio in thf (thf = tetrahydrofuran); the X-ray structure determination shows that the [(pz)₃Ge]^– unit in 1 is a tridentate ligand to the sodium, while the [(pz)₃Sn]^– unit in 2 is only bidentate resulting in dimerisation to produce overall a twelve-membered ring system.