Theoretical investigation of mechanism, stereochemistry, kinetics and thermodynamic of diels-alder reactions of strained molecules

Diels-Alder reactions are studied in detail both experimental and theoretical in recent years. Stereochemistry, mechanism, kinetic and thermodynamic of these reactions are mainly studied as theoretical. In this study, Diels Alder reactions of strained molecules were in detailed investigated. Diels-Alder reactions of three group molecules which are mono-, di-, tricyclic molecules, strained anhydrides and heteromolecules were investigated. The reactions of first and second group with cyclopentadiene and the reactions of third group with furan were studied. Theoretical calculations for each molecules were performed in gas and liquid phase and then their results were compared. Geometric and electronic structure of each diene were investigated by DFT methods and pyramidalization parameters of double bonds, energy of HOMO and LUMO orbitals and electron density on these orbitals were calculated. Relations which are between direction of reactions and these parameters were determined. PES for each reactions were calculated by B3LYP/6-31+G(d,p) and transition states of reactions were determined. In transition states, bond length that are between diene and dienophile and bond order were calculated. According to the stability of transition states and products of reactions, reactions were determined to occur under kinetic or thermodynamic control. According to results from theoretical calculations, experimental results were evaluated and both results were found to be in conformity with.