(IPr)CuF-catalyzed α-site regiocontrolled: Trans -hydrofluorination of ynamides

With Et₃N·3HF as the fluorination reagent, (IPr)CuF-catalyzed α-site regiocontrolled trans-hydrofluorination of ynamides has been achieved, affording (Z)-α-fluoroenamides in moderate to excellent yields. It was interesting to note that the regioselectivity of the reaction is reversed to that observed in the (Ph₃P)₃CuF-catalyzed hydrofluorination of ynamides. Additionally, a variety of different ynamides including oxazolidinonyl-, imidazolyl-, and N-sulfonyl ynamides were suitable for the reaction system and the subsequent oxidation of the fluorinated products enables a convenient synthesis to α-fluoroimides.