EFFECTIVE NEW COBALT(II) DIOXYGEN CARRIERS DERIVED FROM DIMETHYLGLYOXIME BY THE REPLACEMENT OF THE LINKING PROTONS WITH BF-2+

The cobalt(II) complexes of modified dimethylglyoximes in which the linking protons have been replaced by BF2 +groups (abbreviated [Co(R2GlyoxBF2)2] (structure I) and Co(cis-C10GlyoxBF2)] (structure II)) are effective dioxygen carriers. In contrast to the parent compounds, which have linking protons, [Co(R2GlyoxBF2)2] (R = methyl, phenyl, benzyl, mesityl) and [Co(cis-C10GlyoxBF2)] form one-to-one dioxygen complexes of the Pauling type, and in the cases of the (Me2glyoxBF2) and cis-C10GlyoxBF2complexes, it has been shown that the oxygenation-deoxygenation cycle can be repeated many times without noticeable autoxidation. The equilibrium constants for 02adduct formation have been measured for the bridged complex and for the methyl derivative over the temperature range from −20 to 0 °C. The thermodynamic parameters ΔH and ΔS were calculated from the van’t Hoff relationship. © 1990, American Chemical Society. All rights reserved.