SYNTHESES AND C-13 NMR INVESTIGATIONS OF AN EXTENSIVE SERIES OF [HB(3,5-ME2PZ)3]CD(ALKYL) COMPLEXES

The complexes [HB(3,5-Me2pz)3]CdR (pz = pyrazolyl ring; R = methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, phenyl) are prepared by the reaction of dialkylcadmium complexes with 1 equiv of TI[HB(3,5-Me2pz)3]. These complexes are air stable in the solid phase and do not thermally decompose in solution below 80-degrees-C. They undergo ligand-exchange reactions with dialkylcadmium compounds and poly(pyrazolyl)borate complexes of cadmium. The effect of the [HB(3,5-Me2pz)3]Cd group on the chemical shifts in the C-13 NMR spectra of alkyl carbon atoms has been determined. The chemical shifts of the metal-bonded alkyl carbon atoms, especially for the methyl derivative (-17.98 ppm), are shifted to an unusually high field.