Inorganic Chemistry, Vol.42, No.1, 96-106, 2003
Arene-ruthenium complexes of an acyclic thiolate-thioether and tridentate thioether derivatives resulting from ring-closure reactions
The reaction of [(eta(6)-arene)RuCl2](2) (arene = C6Me6, 1,4-MeC6H4CHMe2) with a large excess of the dianion of bis(2-mercaptoethyl) sulfide, (HSCH2CH2)(2)S, obtained from deprotonation of the dithiol with freshly prepared NaOMe, gives the deep red, monomeric complexes [(eta(6)-arene)Ru(eta(3)-C4H8S3)] (arene = C6Me6 (5), 1,4-MeC6H4CHMe2 (6)) in which the dianion is bound to the metal atom through one thioether and two thiolate sulfur atoms. Complex 5 reacts with [(eta(6)-C6Me6)RuCl2](2) (4) in a 2:1 mole ratio to give a quantitative yield of the chloride salt of a binuclear cation [{(eta(6)-C6Me6)Ru}(2)Cl(mu(2)-eta(2):eta(3)-C4H8S3)](+) (7) in which the thiolate sulfur atoms of the [(eta(6)-C6Me6)Ru(eta(3)-C4H8S3)] group bridge to a (eta(6)-C6Me6)RuCl unit. This compound is also obtained directly from the reaction of 4 with the dithiolate, if the Ru dimer is used in large excess. The binuclear complex [{(eta(6)-C6Me6)Ru}(2)(MeCN)(mu(2)-eta(2):eta(3)-C4H8S3)](PF6)(2).MeCN, (9)(PF6)(2).MeCN, is obtained by treatment of (7)Cl with NH4PF6 in acetonitrile. Protonation of 5 with HCl gave the mono- and diprotonated derivatives viz. [(eta(6)-C6Me6)Ru(eta(3)-C4H9S3)]Cl, (8)Cl, and [(eta(6)-C6Me6)Ru(eta(3)-(CH10S3)-H-4)]Cl-2, (10)Cl-2, respectively. The reaction of 5 with methyl iodide gives both the mono- and di-S-methylated derivatives. Treatment of 5 with dibromoalkanes, Br(CH2)(n)Br (n = 1-5), effects ring closure to give the (eta(6)-C6Me6)Ru dications containing the trithia mesocyclic zS3 (z = 8-12) ligands, isolated as their PF6 salts. The X-ray crystal structures of 5, 6, the solvates of (7)Cl and (9)(PF6)2, and the trithia mesocyclic Ru complexes (eta(6)-C6Me6)Ru(zS3)(PF6)(2) (z = 8-11) are reported.