Synthesis of 2-substituted pyrimidines and benzoxazoles via a visible-light-driven organocatalytic aerobic oxidation: enhancement of the reaction rate and selectivity by a base
irradiation (λ > 400 nm) of rhenium(I) complexes (P1−P4), a photochemical conversion from 3,4-dihydropyrimidin-2(1H)-ones to pyrimidin-2(1H)-ones at room temperature has been achieved with good to excellent yields in CH3CN−H2O solution containing CCl4 and K2CO3. Luminescence quenching study and product analysis reveal that photoinduced electron transfer between rhenium(I) complex P and 3,4-dihydropyrimidin-2(1H)-ones