STRUCTURE OF A TETRANUCLEAR COBALT(II)-COBALT(III) COMPLEX OF BIS-(2-HYDROXYETHYL)AMINE, [CO4(NH(C2H4OH)2)2(NH(C2H4O)2(4](CLO4)2

The structure of [Co4DetaH2)2(Deta)4](ClO4)2 (where DetaH2 represents bis(2-hydroxyethyl)amine and Deta2- represents the anion formed by removing two protons from bis(2-hydroxyethyl)amine) has been determined crystallographically and consists of tetranuclear cations and perchlorate anions. The compound crystallizes in the monoclinic space group P21/c with two formula units in a unit cell of dimensions a = 8.747 (2) Å, b = 17.408 (4) Å, c = 13.597 (3) Å, β = 111.45 (2)°, ρ?exptl = 1.80 g/cm3, and ρcalcd = 1.82 g/cm3. The structure was solved by Patterson methods. Least-squares refinement converged at final values of R = 0.045 and Rw = 0.035 for 2719 reflections with I ≥ 2σ(I). The centrosymmetric tetranuclear cation contains two cobalt(III) ions, each coordinated by two tridentate Deta2- ligands in a cis-facial arrangement. These Co(Deta)2- units bridge through the three oxygens of one face to the cobalt(II) ions; one oxygen coordinates both cobalt(II) ions, and each of the other two oxygens coordinates one of the cobalt(II) ions. The octahedral coordination of each cobalt(II) ion is completed by a bidentate (N,0) DetaH2 ligand. Cobalt(III)-oxygen distances range from 1.888 (3) to 1.940 (3) A; cobalt(III)-nitrogen distances are 1.968 (4) and 1.957 (4) A. Cobalt(II)-oxygen distances range from 2.045 (3) to 2.225 (3) A, and the cobalt(II)-nitrogen distance is 2.241 (4) A. © 1979, American Chemical Society. All rights reserved.