Used by many researchers in catalysis, N-Heterocyclic carbenes (NHC) can play a variety of roles in chemistry. Last month, Catherine Cazin and her co-workers at the University of St Andrews have published two articles in ChemComm, showing that their NHC complexes can be successfully used as either transfer agents or for efficiently catalysing ring closing metathesis (RCM) reactions.
The first article reports a way to easily prepare inexpensive copper synthons as NHC transfer agents to generate catalytically active gold and palladium complexes. It is the first example showing the transfer of NHC ligand from one metal centre to another. Furthermore, the resulting gold and palladium complexes are ones that are frequently used in transition metal-mediated catalysis.
The second article reports how a ruthenium-based metathesis catalyst fluctuates between trans- and cis-isomer upon heating. It is the first example of an indenylidene complex bearing monodentate (NHC and phosphite) ligands that exhibit cis-configuration. The catalytic studies also showed that these systems are able to efficiently promote RCM reactions using very low loading levels and seem to last longer than other pre-catalysts currently used.
Both these papers are free to access until the 8th of October, so why not click on the links above, download and read the articles today!
Please feel free to blog any thoughts or comments below too!
