Reaction of [Cp(*)Ru(mu-OMe)](2), 1 with dithiocatechol yields the singly coordinatively unsaturated dinuclear complex Cp(*)Ru(mu(2) eta(4)-oC(6)H(4)S(2))RuCp(*) (7). Reaction of 7 with P(OMe)(3) gave (CP(*)RU>(2)(mu(2):mu(2)-S2C6H4)(P(OMe)(3)) (8) The molecular structure of 8 was determined from single crystal X-ray diffaction (space group P (1) over bar, a=8.367(2),b=11.723(3), c=17.252(8) Angstrom, (alpha=94.71(3), beta= 93.37(3), gamma=69.46(2)degrees, Zeta=2, R=0.056, R(w)=0.055) and reveals strong coordination of one Ru center to a double bond of the bridging dithiocatechol ligand. The reactions are contrasted to those of 1 and 2 with catechol to give exclusively pi-complexation.