Ruthenium‐Catalyzed ortho C−H Borylation of Arylphosphines

Abstract Efficient, phosphine‐directed ortho C−H borylation of arylphosphine derivatives was achieved using Ru catalysts for the first time. The reaction is applicable to various tertiary arylphosphine and arylphosphinite derivatives to give ( o ‐borylaryl)phosphorus compounds in high yields. This reaction enables easy access to a variety of functionalized phosphine ligands and ambiphilic phosphine boronate compounds, thus realizing a new late‐stage modification of phosphorus compounds.