金属触媒を用いた不飽和炭素-炭素結合への硫黄置換基の導入

抄録

A metal-catalyzed introduction of sulfur substituents to unsaturated carbon-carbon bonds is important methodology in organic synthesis. In particular, an addition of thiols is well used as a convenient procedure. As a general rule, the reaction affords anti-Markovnikov type products via a radical process. On the contrary, a report of Markovnikov-type reaction is very restricted. A catalytic procedure has not been extremely exploited. However, we found that a zinc-catalyzed hydrothiolation of alkenes proceeds smoothly in the presence of Brøntsted acid.

A reaction of alkynes with thiols usually affords β-vinyl sulfides via a radical process. The procedure is well researched using various metal catalysts. The reaction can perform region- and stereoselectively. Regrettably, a double hydrosulfenylation of alkynes hardly proceeds. We found that a dihydrosulfenylation of alkyne was promoted by using zinc or nickel catalyst in air, and the desired β-dithioacetals were obtained regioselectively in good yields.

This article describes about a metal-catalyzed convenient regioselective introduction of sulfide-groups to alkenes or alkynes.