Ruthenium-Catalyzed PIII-Directed Remote ε-C–H Alkylation of Phosphines

The ruthenium-catalyzed remote ε-C–H alkylation of phosphines with tertiary alkyl halides has been developed. This novel PIII-directed C–H activation strategy tolerated various functional groups and delivered a wide variety of modified phosphines with excellent meta-site selectivity. Preliminary mechanistic studies indicated that a PIII-assisted ortho-cyclometalation/remote σ-activation pathway might be involved in this methodology.