C-O bond formation between terminal alkenes/benzyl alcohols as an arylcarboxy surrogate and carbonyl compounds in a biodegradable deep eutectic solvent (DES) based on choline chloride and urea was performed. By employment of TBAI as catalyst and TBHP as oxidant, various derivatives of carbonyl compounds were benzylated in ? position in good to high yield at 90 °C. Moreover, ?-oxybenzoylation of diethyl malonate with carboxylic acids were performed in the above-mentioned DES by employment of NaI as the catalyst and
TBHP as the oxidant at 60 °C.