Gas-Phase Pyrolysis Mechanisms of 3-Anilino-1-Propanol: Density Functional Theory Study

The gas-phase pyrolytic decomposition mechanisms of 3-anilino-1-propanol with the products of aniline, ethylene, and formaldehyde or N-methyl aniline and aldehyde were studied by density functional theory. The geometries of the reactant, transition states, and intermediates were optimized at the B3LYP/6-31G (d, p) level. Vibration analysis was carried out to confirm the transition state structures, and the intrinsic reaction coordinate method was performed to search the Minimum energy path. Four possible reaction channels are shown, including two concerted reactions of direct pyrolytic decomposition and two indirect channels in which the reactant first becomes a ring-like intermediate, followed by concerted pyrogenation. One of the concerted reactions in the direct pyrolytic decomposition has the lowest activation barrier among all the four channels, and so, it occurs more often than others. The results appear to be consistent with the experimental outcomes. (C) 2008 Wiley Periodicals, Inc. Int J Quantum Chem 109: 1036-1044, 2009