Cobalt-Catalyzed, Aminoquinoline-Directed Functionalization of Phosphinic Amide sp² C–H Bonds

In this paper, we introduce arylphosphinic acid aminoquinoline amides as competent substrates for cobalt-catalyzed sp² C–H bond functionalization. Specifically, the feasibility of their coupling with alkynes, alkenes, and allyl pivalate has been demonstrated. Reactions are catalyzed by simple Co­(NO₃)₂ hydrate in ethanol or mixed dioxane/<i>t</i>BuOH solvent in the presence of Mn­(OAc)₃·2H₂O additive, sodium pivalate, or acetate base and use oxygen from the air as an oxidant. Directing group removal affords ortho-functionalized <i>P</i>,<i>P-</i>diarylphosphinic acids