Investigation of Oxidation Reaction Products of 2-Phenylethanol Using Synchrotron Photoionization

A photolytically Cl-initiated oxidation reaction of 2-phenylethanol (2PE) was carried out at the Advanced Light Source (ALS) in the Lawrence Berkeley National Laboratory. Using the multiplex photoionization mass spectrometer, coupled with the tunable vacuum ultraviolet radiation of the ALS, data were collected at low pressure (4-6 Torr) and temperature (298-550 K) regimes. Data analysis was performed via characterization of the reaction species photoionization spectra and kinetic traces. Products and reaction pathways are also computed using the CBS-QB3 composite method. The present results suggest primary products m/ z = 30 (formaldehyde), 106 (benzaldehyde), and 120 (phenylacetaldehyde) at 298 K, and m/ z = 120 (phenylacetaldehyde) at 550 K. Branching fractions at room temperature are 27 ± 6.5% for formaldehyde, 24 ± 4.5% for benzaldehyde, and 25 ± 5.8% for phenylacetaldehyde and 60 ± 14% for phenylacetaldehyde at 550 K.