Gas-free alkoxycarbonylation of aryl iodides in a phosphonium-based deep eutectic solvent with Mo(CO) 6 as a solid CO source.

Pd-catalyzed alkoxycarbonylation of aryl iodides has been explored, for the first time, in phosphonium-based deep eutectic solvents under gas-free conditions, by using Mo(CO) 6 as the CO source. The method allows the preparation of ethylene glycol and glycerol esters in high yields (up to 99%), short reaction times and under mild reaction conditions with a very low catalyst loading (0.5 mol%).