Selenourea as a hydrogen bond donor catalyst and source of selenium for metal-, activator-free synthesis of selenoesters in a batch and flow reactor

A new metal- and activator-free method for the synthesis of selenoesters from carboxylic acids, Michael acceptors, and selenourea is reported. This is the first reported method for the synthesis of selenoesters directly from carboxylic acids, using selenourea as a nucleophile, source of selenium, and an activator of carbonyl group. A new multifunctional selenourea (source of selenium, activator, base) has been synthesized, tried in a flow reactor to reduce impurity and reaction time.