Solvent-Controlled Copper-Catalyzed Radical Decarboxylative Coupling for Alkenyl C(sp2)-P Bond Formation

The first solvent-controlled copper-catalyzed oxidative decarboxylative coupling of alkenyl acids with P(O)H compounds for alkenyl C(sp(2))-P bond formation by a freeradical process is reported. The reaction enables the highly chemo-and stereoselective synthesis of various (E)-alkenylphosphonates and (E)-alkenylphosphinate oxides in moderate to good yields. On the basis of this catalytic system, styr-enes and b-nitrostyrene as well as alkenyl acids can also give the corresponding products by cross-dehydrogenative coupling and denitration, respectively. By altering the oxidant, the oxyphosphorylation of styrenes with P(O)H compounds readily yields beta-ketophosphonates. The reaction described here enables a versatile and practical avenue for the formation of valuable C-P bonds.