Palladium-catalyzed C-H alkenylation of arenes using thioethers as directing groups

Thioethers have been proven to be reliable directing groups for palladium catalyzed alkenylation of arenes via C-H activation. Mechanistic investigation reveals that the C-H cleavage of arenes is the turnover-limiting step, and an acetate-bridged dinuclear cyclopalladation intermediate is involved. The alkenylated thioethers can be easily removed and transformed into a variety of useful groups.