Reaction of Alkenesulfonyl Chlorides with Olefins Catalyzed by a Ruthenium(II) Complex. A Novel Method for Synthesis of (E,E)-1,4-Diaryl-1,3-butadienes

Article abstract of DOI:10.1021/jo00225a009

In the presence of a catalytic amount of dichlorotris(triphenylphosphine)ruthenium(II) (1), alkenesulfonyl chloride (2) was found to react with vinylarenes to give 1:1 adducts (3) in high yield under mild conditions.Dehydrochlorination from the adducts 3 to afford divinyl sulfones (4) takes place by raising the reaction temperature from 80 to 130 deg C.Upon further reaction at 150 deg C, (E,E)-1,4-diaryl-1,3-butadienes (5) are formed in high yield if both of the alkenyl substituents of the sulfonyl chloride and the alkene have aryl groups.The time course of the reaction indicates that the addition of 2 to vinylarenes giving 1:1 adducts 3, dehydrochlorination from the adducts 3 giving divinyl sulfones 4, and desulfonylation from the divinyl sulfone 4 giving 1,3-butadienes 5 proceed successively.The usefulness of the reaction for the syntheses of (E,E)-1,4-diaryl-1,3-butadiene is described.On the other hand, 2 reacts with alkyl olefins in the presence of 1 to give 1:1 adducts (12) with extrusion of sulfur dioxide.