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Under carefully controlled experimental conditions, a series of metal nitrate complexes of dibenzylsulfoxide (DBSO) have been synthesized and isolated (for the dipositive Co, Ni, Cu and Zn elements). The compounds were characterized by use of infrared-, ultraviolet-, and visible spectra. Their stoichiometric compositions appeared to be [M- (DBSO) 3 (NO 3 ) 2 ], where MCo, Ni and Cu; and [M(DBSO) 3.5 (NO 3 ) 2 ], where MZn. The additional information concerning the nature of bonding and structural geometry was derived from X-ray diffraction analysis, molecular conductivities, molecular weight and magnetic susceptibility measurements. The infrared spectra indicated that, in all cases, coordination occurred through the oxygen atom of the DBSO ligand. Both analyses and spectral studies suggest that the transition metal ions manifest a coordination number of six. The slight decrease in metal ion radius across the first transition metal series does not affect the number of DBSO molecules bonded to the M 2+ ion, but the only variation in total coordination of cation might be attributed to the DBSO competition with nitrato groups for the coordination site due to the ability of the anion to enter the coordination sphere.

The kinetics of acid hydrolysis of Co(tren)Cl2+ (tren = β,β′,β″-triaminotriethylamine) and Co(tren-d6)2+ have been studied in H2O and D2O at 25°. The solvent and β-deuterium isotope effects for these complexes are quite different from those observed for other CoIII-amine complexes. These data indicate that the solvent isotope effect is dependent on the nature of the complex, and provide further support for the proposed distortion of tren complexes.

Reviews the chemistry of transition metal complexes that are able to bind reversibly to molecular oxygen, particularly complexes of iridium, rhodium, and cobalt.