Rhodium-Catalyzed Enantioselective Defluorinative alpha-Arylation of Secondary Amides

摘要

We exploited the reactivity of an electronically biased Michael acceptor to perform a defluorinative alpha-arylation reaction using a chiral diene(L*)-rhodium catalyst. Through this methodology, we are able to obtain various secondary amides, containing a tertiary alpha-stereocenter and a ,alpha-unsaturated gem-difluoro olefin, with excellent enantioselectivities. This methodology addresses the limitations of the previously described alpha-arylation methods to construct stereo-labile tertiary alpha-stereocenters. Further investigation of the reaction via in situ F-19 NMR monitoring suggests that the formation of the product leads to the inhibition of the active rhodium catalyst.