Gas-Phase Kinetics of Elimination Reactions of Pentane-2,4-Dione Derivatives

Article abstract of DOI:10.1002/kin.550270510

Gas-phase elimination reactions of pentane-2,4-dione, methyl acetoacetate, ethyl acetoacetate, 3-phenylhydroazopentane-2,4-dione, and ethyl 3-oxo-2-phenylhydrazonobutyrate have been measured in the temperature ranges of 744-783, 662-695, 614-663, 604-664, and 503-555 K, respectively, using a flow-thermolysis technique.These compounds undergo unimolecular first-order elimination reactions, for which log A = 11.9, 11.2, 11.7, 11.5, and 11.7 s^-1 and E_a = 198.3, 167.1, 141.7, 165.6, and 141.7 kJ mol^-1, respectively.The kinetic data and product analysis shows that the reactions are highly affected by the electronic nature of the substituents at the carbonyl and methylene carbon atoms of the substrates investigated.