Gas-phase pyrolytic reaction of 3-anilino-1-propanol derivatives: kinetic and mechanistic study

3-Anilino-1-propanol derivatives 4a-c, 5a-c, 6a-c containing primary, secondary, and tertiary alcohols and PhNH, PhNMe, and (Ph)₂N were prepared and subjected to gas-phase pyrolysis in a static reaction system. The pyrolytic reactions were homogeneous and followed a first-order rate equation. Reactions took place by retro-ene process, with the exception of compounds 5a and 5b. Analysis of the pyrolysate showed the products to be N-substituted aniline and carbonyl compounds. The kinetic results and product analysis of each of the nine investigated 3-amino alcohols are rationalized in terms of a plausible transition state for the elimination pathway.