TY - JOUR
T1 - Criegee intermediate decomposition pathways for the formation of o-toluic acid and 2-methylphenylformate
AU - Lakmuang, Chaiyaporn
AU - Kroeger, Asja A.
AU - Karton, Amir
PY - 2020/6
Y1 - 2020/6
N2 - We use Gaussian-4 theory to investigate the reaction mechanism for the conversion of a 2-methylstyrene-based Criegee intermediate into o-toluic acid and 2-methylphenylformate. o-Toluic acid can be formed via an α-hydroxyalkyl-hydroperoxide intermediate with an activation energy of ΔG‡298 = 82.9 kJ mol−1 for the rate-determining-step (RDS). The RDS for the formation of 2-methylphenylformate has an activation energy of ΔG‡298 = 61.9 kJ mol−1. Formation of the o-toluic acid product is more exergonic by 67.4 kJ mol−1. Consistent with recent experimental results, our high-level calculations show that o-toluic acid is the thermodynamic product and 2-methylphenylformate is the kinetic product.
AB - We use Gaussian-4 theory to investigate the reaction mechanism for the conversion of a 2-methylstyrene-based Criegee intermediate into o-toluic acid and 2-methylphenylformate. o-Toluic acid can be formed via an α-hydroxyalkyl-hydroperoxide intermediate with an activation energy of ΔG‡298 = 82.9 kJ mol−1 for the rate-determining-step (RDS). The RDS for the formation of 2-methylphenylformate has an activation energy of ΔG‡298 = 61.9 kJ mol−1. Formation of the o-toluic acid product is more exergonic by 67.4 kJ mol−1. Consistent with recent experimental results, our high-level calculations show that o-toluic acid is the thermodynamic product and 2-methylphenylformate is the kinetic product.
KW - Atmospheric chemistry
KW - CCSD(T)
KW - Criegee intermediates
KW - G4 theory
KW - Unimolecular rearrangement
UR - http://www.scopus.com/inward/record.url?scp=85082866810&partnerID=8YFLogxK
U2 - 10.1016/j.cplett.2020.137399
DO - 10.1016/j.cplett.2020.137399
M3 - Article
AN - SCOPUS:85082866810
SN - 0009-2614
VL - 748
JO - Chemical Physics Letters
JF - Chemical Physics Letters
M1 - 137399
ER -