Dehydration Reaction of Hydroxyl Substituted Alkenes and Alkynes on the Ru2S2 Complex

A variety of inter- and intramolecular dehydration was found in the reactions of [{Ru(P(OCH3)3)2(CH3CN)3}2(μ-S2)](CF3SO3)4 (1) with hydroxyl substituted alkenes and alkynes. Treatment of 1 with allyl alcohol gave a C3S2 five-membered ring complex, [{Ru(P(OCH3)3)2(CH3CN)3}2{μ-SCH2CH2CH(OCH2CHCH2)S}](CF3SO3)4 (2), via C−S bond formation after C−H bond activation and intermolecular dehydration. On the other hand, intramolecular dehydration was observed in the reaction of 1 with 3-buten-1-ol giving a C4S2 six-membered ring complex, [{Ru(P(OCH3)3)2(CH3CN)3}2 {μ-SCH2CHCHCH2S}](CF3SO3)4 (3). Complex 1 reacts with 2-propyn-1-ol or 2-butyn-1-ol to give homocoupling products, [{Ru(P(OCH3)3)2(CH3CN)3}2{μ-SCRCHCH(OCH2C⋮CR)S}](CF3SO3)4 (4:  R = H, 5:  R = CH3), via intermolecular dehydration. In the reaction with 2-propyn-1-ol, the intermediate complex having a hydroxyl group, [{Ru(P(OCH3)3)2(CH3CN)3}2{μ-SCHCHCH(OH)S}](CF3SO3)4 (6), was isolated, which further reacted with 2-propyn-1-ol and 2-butyn-1-ol to give 4 and ...