The mystery of the benzene-oxide/oxepin equilibrium
- The equilibrium between benzene oxide (1) and oxepin (2) is of large importance for understanding the degradation of benzene in biological systems and in the troposphere. Our studies reveal that at cryogenic temperatures, this equilibration is governed by rare heavy-atom tunneling. In solid argon at 3 K, 1 rearranges to 2 via tunneling with a rate constant of approximately 5.3×10−5 s−1. Thus, in a nonpolar environment, 2 is slightly more stable than 1, in agreement with calculations at the CCSD(T) level of theory. However, if the argon is doped with 1 % of H2O or CF3I as typical hydrogen or halogen bond donors, respectively, weak complexes of 1 and 2 are formed, and now 2 is tunneling back to form 1. Thus, by forming non-covalent complexes, 1 becomes slightly more stable than 2 and the direction of the heavy-atom tunneling is reversed.
| Author: | Tim SchleifORCiDGND, Melania Prado MeriniORCiDGND, Wolfram SanderORCiDGND |
|---|---|
| URN: | urn:nbn:de:hbz:294-99289 |
| DOI: | https://doi.org/10.1002/anie.202010452 |
| Parent Title (German): | Angewandte Chemie International Edition |
| Subtitle (German): | heavy-atom tunneling reversed by solvent interactions |
| Publisher: | Wiley-VCH |
| Place of publication: | Hoboken, New Jersey |
| Document Type: | Article |
| Language: | English |
| Date of Publication (online): | 2023/05/30 |
| Date of first Publication: | 2020/08/20 |
| Publishing Institution: | Ruhr-Universität Bochum, Universitätsbibliothek |
| Tag: | halogen bonding; matrix isolation; noncovalent interactions; rearrangement; tunneling |
| Volume: | 59 |
| Issue: | 46 |
| First Page: | 20318 |
| Last Page: | 20322 |
| Note: | Dieser Beitrag ist auf Grund des DEAL-Wiley-Vertrages frei zugänglich. |
| Institutes/Facilities: | Lehrstuhl für Organische Chemie II |
| open_access (DINI-Set): | open_access |
| faculties: | Fakultät für Chemie und Biochemie |
| Licence (English): |  Creative Commons - CC BY-NC-ND 4.0 - Attribution-NonCommercial-NoDerivatives 4.0 International |
