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Isolating Free Carbenes, their Mixed Dimers and Organic Radicals
Published on: April 19, 2019
Bicyclic (Alkyl)(amino)carbenes (BICAACs): Stable Carbenes More Ambiphilic than CAACs
Eder Tomás-Mendivil1,2, Max M Hansmann1, Cory M Weinstein1
1UCSD-CNRS Joint Research Chemistry Laboratory (UMI 3555), Department of Chemistry and Biochemistry, University of California, San Diego , La Jolla, California 92093-0358, United States.
Abstract:
A straightforward strategy allows for the synthesis of storable bicyclic (alkyl)(amino)carbenes (BICAACs), which feature enhanced σ-donating and π-accepting properties compared to monocyclic (alkyl)(amino)carbenes (CAACs). Due to the bicyclo[2.2.2]octane skeleton, the steric environment around the carbene center is different from that of CAACs and similar to that observed in classical N-heterocyclic carbenes. The different electronic properties of BICAACs as compared to CAACs allow for ligand exchange reactions not only at a metal center, but also at main group elements.
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