Rhodium-Catalyzed Enantioposition-Selective Hydroarylation of Divinylphosphine Oxides with Aryl Boroxines.

The rhodium-catalyzed hydroarylation of divinylphosphine oxides (RP(O)(CH=CH2 )2 ) with aryl boroxines ((ArBO)3 ) gives the corresponding monoarylation products (RP(O)(CH=CHAr)CH2 CH3 ) in high yields. One of the two vinyl groups in the phosphine oxide undergoes oxidative arylation while the other one is reduced to an ethyl moiety. These reactions proceed with high selectivity in terms of the enantiotopic vinyl groups in the presence of (R)-DTBM-segphos/Rh to give the P-stereogenic monoarylation products with high enantioselectivity.