Syntheses and crystal structures of [Bp~(Bu~t, Me)]ZnX, [Bp~(Bu~t, Pr~i)]ZnX (X = Me, I) and {[Bp~(Bu~t, Me)]Cd(#mu#-I)}_2: mononuclear versus dinuclear bis(pyrazolyl)hydroborato zinc and cadmium complexes

摘要

The bis(pyrazolyl)hydroborato zinc and cadmium complexes, [Bp~(Bu~t, R]ZnX (R = Me, Pr~i; X = Me, i) and {[Bp~(Bu~t, Me]Cd(#mu#-I)}_2 are obtained readily by reaction of the respective thallium reagents Tl[Bp~(Bu~t, R] with MX_2. The molecular structures of [Bp~(Bu~t, Pr~i)]ZnX (X = Me, I) and {[Bp~(Bu~t, Me]Cd(#mu#-I)}_2 have been determined by X-ray diffraction, demonstrating that the zinc complexes are mononuclear with a trigonal planar coordination geometry, whereas the cadmium complex is dinuclear. As such, the observation demonstrates that cadmium shows less of a preference to form trigonal planar three-coordinate complexes than does zinc.