Metal Tetrahydroborates and Tetrahydroboratometalates, 18 [1] Studies on the Formation of Cadmium(II)-tetrahydroborates with Tetrahydroborate and Iodide

Heinrich Nöth*, M artina Thom ann Institute of Inorganic Chemistry, University of Munich, Meiserstraße 1, D-80333 München Z. Naturforsch. 49b, 9-14 (1994); received August 30, 1993 Cadmium Bis(tetrahydroborate), Tris(tetrahydroborato)cadmate, Tetrakis(tetrahydroborato)cadmate, Iodo Tetrahydroborato Cadmates, nB NMR Spectra, U3Cd NMR Spectra The structure of cadmium tetrahydroborate in THF solution is fluxional on the NMR time scale and best described as Cd[(a-H)2BH2]2rcTHF as indicated by IR data. Reactions of LiBH4 with Cd(BH4)2 in THF yield the monoanion [Cd(BH4)3]_ exclusively, while a dilithium salt Li2[Cd(BH4)4] • 4 diglyme precipitates from diglyme solutions. Equilibria involving ICd(BH4), Cdl2, Cdl3~, [Cd(BH4)3]and/or [ICd(BH4)2]~ result from Cd(BH4)2 and Lil in THF or diglyme. The solvent as well as the cation of the iodide (Cd2+ or Li+) influence the equilibria. This can be explained in terms of the different polarity and chelating ability of the solvents.