Abstract A chemoselective synthesis of tetraketone and xanthene derivatives, by means of tandem Knoevenagel condensation and Michael addition in choline chloride-based deep eutectic solvents (DESs), is presented. The reaction of readily available aldehydes and active methylene compounds in malonic acid-and ZnCl 2-based DES gives various xanthenes derivatives with good to excellent yields under mild reaction conditions. On the ...