Realizing Metal-Free Carbene-Catalyzed Carbonylation Reactions with CO

Many organic and main-group compounds,
usually acids or bases,
can accelerate chemical reactions when used in substoichiometric quantities,
a process known as organocatalysis. In marked contrast, very few of
these compounds are able to activate carbon monoxide, and until now,
none of them could catalyze its chemical transformation, a classical
task for transition metals. Herein we report that a stable singlet
ambiphilic carbene activates CO and catalytically promotes the carbonylation
of an o-quinone into a cyclic carbonate. These findings
pave the way for the discovery of metal-free catalyzed carbonylation
reactions.