Niobia as an efficient catalyst for the epoxidation of dicyclopentadiene

We studied the epoxidation of dicyclopentadiene (DCPD) with hydrogen peroxide over different heterogeneous catalysts. Among them, niobium pentoxide (Nb2O5) catalysts showed promising catalytic activity, giving mono- and di-epoxy DCPD with low amounts of epoxidation byproducts. The epoxidation activity of Nb2O5 largely depends on the reaction solvents. Higher epoxidation performance was observed in the solvents with a certain range of dielectric constants (30 < εr < 40), such as methanol and acetonitrile. The crystallinity of the Nb2O5 catalysts was modified by calcination temperature, which influences the formation of surface peroxo species, and consequently, the extent of the DCPD epoxidation.