Stereoselective Hydrogenation of Interior Alkynes over Silicon Carbide‐Supported Palladium Catalysts

Abstract Hydrogenation of interior alkynes with H 2 over supported Pd catalysts typically produces a mixture of alkanes, as well as both cis ‐ and trans ‐alkenes, as the dissociation of H 2 and activation of C≡C and C═C bonds all take place on the Pd surface. To date, only Lindlar catalysts can be industrially used to produce cis ‐alkenes. Herein, we report that SiC‐supported Pd catalysts exhibit exceptional stereoselectivity in the hydrogenation of interior alkynes to cis ‐alkenes. This exceptional stereoselectivity is attributed to a cooperative catalysis of metal Pd and SiC support. Specifically, the SiC surface activates alkynes, whereas the Pd surface dissociates H₂ into reactive hydrogen species. These species then migrate to the SiC surface and react with the activated alkynes to form cis ‐alkenes. The characteristic of SiC surface will provide new strategies for the design of selective hydrogenation catalysts.