Manganese‐Mediated Intermolecular Arylation of H‐Phosphinates and Related Compounds

The intermolecular radical functionalization of arenes with aryl and alkyl H‐phosphinate esters, as well as diphenylphosphine oxide and H‐phosphonate diesters, is described. The novel catalytic Mn^II/excess Mn^IV system is a convenient and inexpensive solution to directly convert C_sp2?H into C?P bonds. The reaction can be employed to functionalize P‐stereogenic H‐phosphinates since it is stereospecific. With monosubstituted aromatics, the selectivity for para‐substitution increases in the order (RO)₂P(O)H<R¹P(O)(OR)H<Ph₂P(O)H, a trend that may be explained by steric effects.