Pyrolysis of polycyclic perhydroarenes. 3. 1-n-decylperhydropyrene and structure-reactivity relations

1-n-Decylperhydropyrene (DPP) was pyrolyzed neat at temperatures between 400 and 475 °C. DPP disappearance followed first-order kinetics, and the Arrhenius parameters for the first-order rate constant were A (s^-1) = 10^9.5±5.0 and E = 42.9 ± 16.5 kcal/mol, where the uncertainties are the 95% confidence intervals. DPP pyrolysis generated numerous primary products, and the primary products with the highest initial selectivities were, in order of decreasing abundance, perhydropyrene plus 1-decene, methylene perhydropyrene plus n-nonane, tetradecahydropyrene plus n-decane, and methylperhydropyrene plus nonene. This ordering of product pairs is completely analogous to that observed from pyrolysis of an alkylcyclohexane, but it differed from that observed for the pyrolysis of other polycyclic n-alkylnaphthenes. Eight other n-alkylperhydroarenes were pyrolyzed at temperatures between 400 and 450 °C. The resulting kinetics data were used to test three structure-reactivity correlations in the literature for the pyrolysis kinetics of saturated cyclic compounds and to update one of these correlations so that it becomes consistent with the kinetics of long-chain n-alkylperhydroarenes.