Kinetics of the Diels–Alder addition of acrolein to cyclohexa‐1,3‐diene and its reverse reaction in the gas phase

Abstract

Abstract The Diels–Alder addition of acrolein to cyclohexa‐1,3‐diene has been studied between 486 and 571°K at pressures ranging from 55 to 240 torr. The products are endo‐ and exo‐5‐formylbicyclo[2.2.2]oct‐2‐ene (endo‐ and exo‐FBO), and their formations are second order. The rate constants (in l./mole · sec) are given by The retro‐Diels–Alder pyrolysis of endo‐FBO has also been studied. In the ranges of 565–638°K and 6–38 torr, the reaction is first order, and its rate constant (in sec −1 ) is given by The reaction mechanism is discussed. The heat of formation and the entropy of endo‐FBO are estimated.