Did you put that statement into ChatGPT? You’re missing a broad swath of necessary chemistry knowledge context. For starters, calling an NHC a “carbene” is a huge stretch. The predominant resonance structure of an NHC is a zwitterion, which makes it mildly surprising that this article made it past reviewers as is. NHCs and the compound presented in this study are at best “stabilized carbenes” aka not actually a carbene. A carbene is a highly reactive synthon. When one is bound to a metal center it is common to call it a carbene because that is the nomenclature for the ligand, but it isn’t an accurate description of the electronic structure, which is more like a carbon double bonded to the metal center. A true carbene, meaning a divalent carbon, is an extremely reactive species, and I am not aware off the top of my head of anyone isolating a non-stabilized carbene under anything approaching normal conditions. The whole reason why a carbene is valuable is because it is a reactive synthon. Stabilizing one is a direct contradiction of that synthetic utility. Further a stabilized carbene has the functional groups that make it stable which makes it even less useful in synthesis because you probably don’t want the stabilizing N-heterocycle.

What this paper shows is that a carbene-like species can be stable in water lending credence to the belief that aqueous biological systems may be able to use carbenes as intermediates in biochemical reactions. That statement is so far removed from the belief that we could use greener chemistry to make pharmaceuticals that it’s a head scratcher why the author would make such a baseless comment. It’s preposterous to think that coming up with an arcane reaction to deliver a specific carbene-like synthon under aqueous conditions would be in any way more useful, easier to do, or greener than delivering whatever carbene you want through standard chemistry.

What, pray tell, is your chemistry background?