Copper-catalyzed radical -selective hydroboration of ynamides with -heterocyclic carbene boranes.

Vinylboron compounds are important compounds in organic chemistry and biology. In this communication, we developed a copper(I)-catalyzed, highly regio- and stereoselective radical -hydroboration of ynamides with -heterocyclic carbene (NHC)-ligated borane is reported, which leads to a series of -boryl enmides that can be conveniently transformed into various multi-substituted enamides. Further investigation showcased that our method is robust and scalable. The mechanism of this unique reaction is studied and discussed.