Scott S. Mason

Bis[dihydrobis(1-pyrazolyl)borate]cadmium(II): a monomeric, severely distorted tetrahedral complex of cadmium(II)☆

Abstract The crystal structure of the complex [H 2 B(pz) 2 ] 2 Cd has been determined: orthorhombic, Pbca, a = 16.052(3), b = 13.935(3), c = 14.974(4) A , V = 3349.4(13) A 3 , Z = 8, R(F) = 3.61% . It is the first structurally characterized non-porphyrin CdN 4 complex. It is monomeric in the solid state with a pseudotetrahedral geometry about the cadmium atom. The NCdN angles are distorted by the approximate 93° bite angle of the ligand; the interligand NCdN angles also are distorted, ranging from 106.9 to 131.7°. These distortions are the result of intermolecular packing forces and are facilitated by the spherical set of valence orbitals for Cd 2+ .

Solution state 113Cd NMR investigation of an extensive series of [HB(3,5-Me2pz)3]Cd(alkyl) complexes

Abstract Analysis of the 113Cd NMR chemical shifts of a series of alkylcadmium complexes of the formula [HB(3,5-Me2pz)3]CdR (R = methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl and phenyl) demonstrates that the large chemical shift difference between the methyl and ethyl derivatives of alkylcadmium complexes is simply a β effect. On average, substitution of a hydrogen atom in [HB(3,5-Me2pz)3]CdCH3 by an alkyl substituent causes a chemical shift of the 113Cd resonance by 49.2 ppm in the shielding direction. The γ and δ and effects are negligible.