Cl2 molecular elimination reaction from 1,2-dichloroethane

The transition state energy for Cl2 molecular elimination from 1,2-dichloroethane is computed at compostite CBS-Q (based on B3LYP/6-31++G(d) optimized structure) and G3MP2 (based on MP2/6-31++G(d) optimized structure) levels of theory. Forward rate constants are calculated as 4.25E11 T0.826·exp(−93.4 kcal mol−1/RT) and 7.62E10 T0.892·exp(−98.5 kcal mol−1/RT) s−1, respectively for these two methods. Intrinsic reaction coordinate (IRC) analysis is performed to verify the transition state structures. While the overall, elimination of Cl2 plus olefin formation has a relative low ΔHrxn; the reaction with these barriers is evaluated to be not important in thermal reactions of chlorocarbons.