Asymmetric copper-catalyzed alkynylallylic monofluoroalkylations with fluorinated malonates
Han-Yu Lu1,2,3, Zi-Han Li1,3, Guo-Qiang Lin1,2
1State Key Laboratory of Chemical Biology, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Shanghai, 200032, China.
Abstract:
The unprecedented copper-catalyzed asymmetric alkynylallylic monofluoroalkylation reaction is described via the use of 1,3-enynes and fluorinated malonates. A series of 1,4-enynes bearing a monofluoroalkyl unit are achieved in high yields, excellent regio- and enantioselectivity and high E/Z selectivity. The asymmetric propargylic monofluoroalkylation is also developed. The reliability and synthetic value of the work are highlighted by a gram-scale test and a couple of downstream transformations. Preliminary mechanistic studies unveil a negative nonlinear effect for the catalytic process.
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