Direct synthesis of alkynylphosphonates from alkynes and phosphite esters catalyzed by Cu/Cu2O nanoparticles supported on Nb2O5

The aerobic oxidative coupling of alkynes and phosphite esters can be catalyzed by Cu/Cu2O nanoparticles supported on Nb2O5 (Cu/Cu2O@Nb2O5) to efficiently afford alkynylphosphonates. The catalyst can be reused by filtration and reduction. According to the results of control experiments and characterization data, the supporter Nb2O5 can reduce the electronic density of Cu and absorb the phosphite esters due to its strong Lewis acid sites, which may enhance the reaction efficiently.