Transmetalation of palladium enolate and its application in palladium-catalyzed homocoupling of alkynes: A room-temperature, highly efficient route to make diynes

A Lei, M Srivastava, X Zhang

Index: Lei, Aiwen; Srivastava, Manisha; Zhang, Xumu Journal of Organic Chemistry, 2002 , vol. 67, # 6 p. 1969 - 1971

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Citation Number: 186

Abstract

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.