Oxygen-vacancy-boosted visible light driven photocatalytic oxidative dehydrogenation of saturated N-heterocycles over Nb2O5 nanorods

Modulation of photoelectrochemical properties and facilitation of O2 adsorption through defective sites is of great significance for photocatalytic O2-involved organic transformations. Herein, we report an oxygen-vacancy (OV)-rich semiconductor Nb2O5 nanorod via N atoms doping strategy for visible-light driven oxidative dehydrogenation (ODH) of saturated N-heterocycles at room temperature. A spectrum of pharmaceutically important unsaturated N-heteroarene including C-nucleoside analogues was synthesized in good to excellent yields with good tolerance of functional groups. Remarkably, the catalyst is reusable up to 10 times with high stability and is also applicable for gram-scale synthesis under visible light or even sunlight illumination, highlighting the potential for practical application. Comprehensive characterizations and theoretical calculations reveal that the OVs play an essential role on effectively enhancing visible light response and accelerating separation efficiency for photogenerated hole-electron pairs, and also greatly facilitating adsorption and activation of molecular O2 and reactant, thereby substantially boosting the photocatalytic activity.