Abstract Procedures for the dimerization of acrolein to form 3, 4-dihydro-2H-pyran-2- carboxaldehyde by microwave induced synthesis have been developed. Significant rate- enhancement and yield increase were observed. 3, 4-Dihydro-2H-pyran-2-carboxaldehyde was obtained in 91% yield under microwave irradiation for 5 minutes instead of 39% yield by reacting at 190 C for 40 min or at 160 C for 4 hr.
