Continuous-Flow Sequential Schotten–Baumann Carbamoylation and Acetate Hydrolysis in the Synthesis of Capecitabine

Capecitabine is an important anticancer drug whose synthesis comprises late-stage carbamoylation and ester hydrolysis. Herein we report the use of the Schotten–Baumann reaction in order to perform these transformation in one pot both in batch and under continuous flow. In batch, capecitabine was obtained in 82% yield in 5 h, while under continuous flow it was obtained in 81% yield in 30 min. This one-pot reaction reduces the chemical waste produced, labor, time, and cost and additionally comprises the use of environmentally friendly solvents and reagents as well as energy-efficient and safe methods, all of which fulfill the requirements of a green process.