ChemRxiv
These are preliminary reports that have not been peer-reviewed. They should not be regarded as conclusive, guide clinical practice/health-related behavior, or be reported in news media as established information. For more information, please see our FAQs.
Cressy_et_al_manuscript_and_SI.pdf (10.34 MB)
0/0

Tuning Rh(II)-Catalyzed Cyclopropanation with Tethered Thioether Ligands

preprint
submitted on 05.08.2020 and posted on 06.08.2020 by Derek Cressy, Cristian Zavala, Anthony Abshire, William Sheffield, Ampofo Darko
Dirhodium(II) paddlewheel complexes have high utility in diazo-mediated cyclopropanation reactions and ethyl diazoacetate is one of the most commonly used diazo compounds in this reaction. In this study, we report our efforts to use tethered thioether ligands to tune the reactivity of Rh-carbene mediated cyclopropanation of olefins with ethyl diazoacetate. Microwave methods enabled the synthesis of a family of Rh-complexes in which tethered thioether moieties were coordinated to axial sites of the complex. Different tether lengths and thioether substituents were screened to optimize cyclopropane yeilds and minimize side product formation. Furthermore, good yields were obtained when equimolar diazo and olefin were used. Structural and spectroscopic investigation revealed that tethered thioethers changed the electronic structure of the rhodium core, which was instrumental in the performance of the catalysts. Computational modeling of the catalysts provided further support that the tethered thioethers were responsible for increased yields.

History

Email Address of Submitting Author

adarko@utk.edu

Institution

University of Tennessee

Country

United States of America

ORCID For Submitting Author

0000-0003-1725-4907

Declaration of Conflict of Interest

No conflict of interest

Exports