STABILIZING OF THE RU-2(6+) CORE - USE OF HIGHLY CHARGED LIGANDS SUCH AS SULFATE AND PHOSPHATE

A new, more convenient, and cleaner synthetic route starting from an Ru2(II,III) carbonate complex to RU2(II,III) sulfate complexes has been developed. This route has also provided, for the first time, a new RU2(II,III) phosphate complex, K4[RU2(HPO4)3(PO4)(H2O)2] (1). Electrochemical oxidation has further transformed these sulfate and phosphate complexes to the corresponding Ru2(III,III) CoMPleXeS. Magnetic susceptibility measurements on K2[RU2(SO)4)4(H2O)2] from 10 to 300 K have confirmed the assignment of the ground state as one arising from an unusual sigma2pi4deltapi*2delta* configuration. The crystal structure of 1 has been determined to be as follows. Space group P2(1)/n (No. 14), a=9.049(l), b=9.418(1), c=10.235(1) angstrom, beta=90.480(9)-degrees, V=872.2(2) angstrom3, Z=2, R=0.023, Ru-Ru distance=2.3052(4) angstrom.