Transmetalation of palladium enolate and its application in palladium-catalyzed homocoupling of alkynes: a room-temperature, highly efficient route to make diynes.
A novel pathway for the homocoupling reaction has been achieved using a similar protocol as the cross-coupling reaction. Ethyl bromoacetate is chosen to initiate the coupling reaction through oxidative addition to a Pd(0) species, and an PdBr(enolate) intermediate is formed. This intermediate can undergo double transmetalation with an alkynyl copper reagent, and reductive elimination produces a variety of diynes in high yields.
Lei
Aiwen
A
Department of Chemistry, Pennsylvania State University, 152 Davey Laboratory, University Park, Pennsylvania 16802, USA.
Srivastava
Manisha
M
Zhang
Xumu
X