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Updated: May 1, 2026

Isotopic Effect in Double Proton Transfer Process of Porphycene Investigated by Enhanced QM/MM Method
Published on: July 19, 2019
A general approach to mechanism in multiproduct reactions: product-specific intermolecular kinetic isotope effects
Shuhuai Xiang1, Matthew P Meyer
1Department of Chemistry and Biochemistry, University of California , Merced, California 95343, United States.
Abstract:
Here we report a general method for the measurement of (13)C kinetic isotope effects at natural abundance for reactions that yield two or more products concurrently. We use, as an example, a recently reported Co-catalyzed reaction between cyclopentene and 1-phenyl-1-propyne. High-precision intermolecular (13)C isotope effects are reported for both the formal [2+2] cycloaddition (major) and Alder-ene (minor) reaction products. Mechanistic possibilities that are in accord with observed isotope effect measurements are discussed.
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