Late-Stage Diversification of Biarylphosphines throughRhodium(I)-Catalyzed C–H Bond Alkenylation with Internal Alkynes

We report herein P­(III)-directed C–H bond alkenylation of (dialkyl)- and (diaryl)­biarylphosphines using internal alkynes. Chloride-free [Rh­(OAc)­(COD)]2 acts as a better catalyst than commercially available [RhCl­(COD)]2. Conditions were developed to control the mono- and difunctionalization depending on the alkyne stoichiometry. One of these novel bisalkenylated (dialkyl)­biarylphosphines was employed for the preparation of a palladium­(II) complex, and some of these functionalized ligands outperformed their corresponding unfunctionalized phosphines in Pd-catalyzed amidation with sterically hindered aryl chlorides.