Synthesis and structural characterization of an ether-bridged cobalta-bis(dicarbollide): a model for Venus flytrap cluster reagents

Abstract

The synthesis of bis-(1-carboranylmethyl) ether was first published in 1963; however, its subsequent complexation with a transition metal was never reported. We now report the complexation of cobalt and the corresponding X-ray structure for the triphenylmethylphosphonium salt of the cobalta-bis(carboranylmethyl) ether. The cobalt complex crystallized in the monoclinic space group C2/c with a = 21.729(6) Å, b = 9.845(2) Å, c = 35.565(9) Å, β = 105.363(9)°, V = 7336 Å3, and Z = 8. Data were collected using CuKα radiation, to a maximum 2θ = 115°, giving 4123 unique reflections, and the structure was solved by heavy atom methods. The final discrepancy index was R = 0.093, Rw = 0.100 for 1919 independent reflections with I > 3σ(I). This metala-bis(carboranylalkyl) ether is the first in a new class of Venus flytrap compounds (VFC), containing an ether linkage, to be synthesized as model compounds for the development of reagents suitable for use in the radioimmunodetection and radioimmunotherapy of cancer. Keywords: cobalt, radioimmunodetection, radioimmunotherapy, Venus flytrap.