Theoretical study of the Diels-Alder Reaction in the Synthesis of Abietane Diterpenes

Density functional theory (DFT), at the B3LYP/6-311 G(d,p) level of theory and Moller-Plesse Theory (MP2/6-311 G(d,p) has been performed to study the mechanism, potential energy surface of the Diels-Alder Reaction in the Synthesis of Abietane Diterpenes. The obtained results indicate that the reaction is concerted and synchronous process, which is interpreted with Frontier Orbital Theory. And finally, The enthalpies and activation energies of reactions are given, -36.6710 kJ·mol^-1 and 180.2946 kJ·mol^-1, respectively. The reaction is exothermic, which is in full agreement with experimental observations.