Abstract

Cross-coupling reactions of alcohols and anilines for the synthesis of imines and secondary amines are highly atom-efficient processes. In this study, a visible light photocatalytic procedure was developed for the synthesis of imines on Au nanoparticles supported on TiO2 nanosheets. AuNPs/TNSs drive the photocatalytic dehydrogenation of the alcohol into an aldehyde, accompanied by the formation of molecular hydrogen, resulting in the condensation of the aldehyde with aniline to obtain the respective imine. Biomass-derived alcohols such as vanillyl, veratryl alcohol, and myrtenol were successfully evaluated in the dehydrogenative condensation with aniline to obtain the respective imines in high yields. Electrochemical analysis confirmed that the high yield of imine (95%) is due to the strong interaction of Au nanoparticles with the TiO2 nanosheet support, which generates a better separation of the photogenerated electron-hole pairs and a faster interfacial charge transfer, which improves the photocatalytic properties related to the calculated values of photonic efficiency (xi).