Novel dicyanido-bridged dicationic RuIIISSRuIII complexes [{ Ru(P(OCH3)3)2}2(µ-S2)(µ-X)2{µ-m-C6H4(CH2CN)2}]- (CF3SO3)2 (4, X Cl, Br) were synthesized by the abstraction of the two terminal halide ions of [{RuX(P(OCH3)3)2}2- (µ-S2)(µ-X)2] (1, X = Cl, Br) followed by treatment with m-xylylenedicyanide. 4 reacted with 2,3-dimethylbutadiene to give the C4S2 ring-bridged complex [{ Ru(P(OCH3)3)2}2{µ-SCH2C(CH3)=C(CH3)CH2S}(µ-X)2{µ-m-C6H4(CH2-CN)2}](CF3SO3)2 (6, X Cl, Br). In addition, 4 reacted with 1-alkenes in CH3OH to give alkenyl disulfide complexes [{Ru(P(OCH3)3)2}2{µ-SS(CH2CCHR)}(µ-CI)2{µ-m-C6H4(CH2CN)2}](CF3SO3) (7: R CH2CH3, 9: R = CH2- CH2CH3) and alkenyl methyl disulfide complexes [{Ru(P(OCH3)3)2}2{µ-S(CH3)S(CH2C=HR)}(µ-Cl)2{µ-m-C6H4(CH2- CN)2}](CF3SO3)2 (8: R = CH2CH3, 10: JR = CH2CH2CH3) via the activation of an allylic C-H bond followed by the elimination of W or condensation with CH3OH. Additionally, the reaction of 4 with 3-penten-1-ol gave [{Ru- (P(OCH3)3)2}2{µ-SS(CH2C=CHCH2OH) }(µ-Cl)2{µ-m-C6H4(CH2CN)2}](CF3SO3) (11) via the elimination of H+ and [{Ru(P(OCH3)3)2}2(µ-SCH2CH=CHCH2S)(µ-Cl)2{µ-m-C6H4(CH2CN)2}](CF3SO3)2 (12) via the intramolecular elimination of a H2O molecule. 12 was exclusively obtained from the reaction of 4 with 4-bromo-1-butene. [ABSTRACT FROM AUTHOR]