We recently developed a cross-course collaborative experiment involving borodeuteride reduction of acetophenone in the sophomore organic laboratory, followed by determination of a kinetic isotope effect (KIE) for hypochlorite oxidation of the 1-phenylethanol product in the physical chemistry laboratory. The reduction/labeling experiment works quite effectively for the organic students, incorporating NMR and GC-MS in the analysis of the isotopically labeled alcohol. The KIE experiment also works well for the physical chemistry students, reinforcing GC-MS use for identification of isotopes (qualitative) measurement of rate (quantitative) and illustrating the application of labeled compounds for determination of KIE. However, at times we have observed variation in the observed rates for the oxidation reaction as well as an apparent induction period. The KIE experiment is based on a biphasic oxidation involving aqueous hypochlorite (bleach) and an ethyl acetate solution of 1-phenylethanol with naphthalene as an internal standard. We investigated parameters for the oxidation reaction in a systematic way, controlling for potential influences such as light, temperature and pH. Our results to date will be presented.

Assessment of variability in a kinetic isotope effect experiment based on a biphasic oxidation

251st National Meeting (2016)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.