Abstract
The synthesis of several new oxidation products of tris(N,N′-disubstituted dithiocarbamato)ruthenium(III), Ru(R2dtc)3, where R = C2H5 and CH3 is described. Photolysis of Ru(Et2dtc)3 in CHCl3 or CH2Cl2 or reaction with gaseous HCl in benzene yields two new chlorine-containing compounds. One of the compounds is green and is formulated as Ru(Et2dtc)3Cl. The crystal structure of this compound has been determined by three-dimensional single-crystal x-ray analysis. The space group is P21/c with lattice constants a = 9.077 (3) Å, b = 10.244 (3) Å, c = 27.805 (13) Å, and β = 93.06 (3)°. The structure was solved by conventional heavy-atom techniques and refined by least-squares methods to a conventional R of 0.055 for 1061 independent reflections. The density of 1.50 g/cm3 computed from the unit cell volume of 2582 Å3 on the basis of four Ru[S2CN(C2H5)2]3Cl molecules per unit cell agrees well with the 1.53 g/cm3 determined by flotation methods. The structure consists of well-separated monomeric molecules, each composed of three bidentate Et2dtc ligands and a chlorine atom with the donor atoms arranged in a distorted pentagonal-bipyramidal configuration around the ruthenium(IV) ion. Two Et2dtc ligands span equatorial positions while one spans an equatorial and an axial position. The chlorine atom occupies the other axial position. The average Ru-S distance is 2.40 Å and the distances between adjacent sulfur atoms in the equatorial plane are very similar and range from 2.75 to 3.02 Å, all of which are much shorter than the van der Waals contact distance of 3.4 Å. The reaction chemistry of Ru(Et2dtc)3Cl is discussed, the most notable reaction being with AgBF4 in acetone solution which yields [Ru2(Et2dtc)5]BF4, thiuram disulfide, and Ru(BF4)3. The general nature of the oxidation reaction of Ru(R2dtc)3 is discussed and related oxidation reactions with iodine are described. 1H NMR properties of Ru(Et2dtc)3Cl are also discussed in detail.