Synthesis of Furan-3-carboxylic and 4-Methylene-4,5-dihydrofuran-3-carboxylic Esters by Direct Palladium Iodide Catalyzed Oxidative Carbonylation of 3-Yne-1,2-diol Derivatives
A variety of 3-yne-1,2-diol derivatives 1, bearing a primary or secondary alcoholic group at C-1, have been efficiently converted into high value added furan-3-carboxylic esters 2 in one step by PdI2/KI-catalyzed directoxidativecarbonylation, carried out in alcoholic media under relatively mild conditions (100 °C under 40 atm of a 4/1 mixture of CO and air). Carbonylated furans 2 were obtained in