An efficient HOTf-catalyzed 1,4-addition reaction of difluoroenoxysilanes to chromones was developed, providing rapid access to valuable C2-difluoroalkylated chroman-4-ones. 3g showed antiproliferative effect on HCT116 cells with an IC50 of 6.37 μM.
An asymmetric difluoroalkylation using α,α-difluoroenol as the key synthon has been disclosed, providing oxindoles containing a chiral quaternary carbon center in generally good yields and with excellent stereoselectivities.
A visible light-promoted strategy for arylthiodifluoromethylation of thiosulfonates and difluoroenoxysilanes has been developed.
Chiral difluorinated tertiary alcohols are obtained in moderate to excellent yields and high enantioselectivities upon a Cu(II)-catalysed reaction of difluorinated silyl enol ethers and acylpyridine N-oxides.
This tutorial review discusses the role of C–F⋯H–X hydrogen-bonding interactions in enabling new reactivity, as well as enhancing the regioselectivity and enantioselectivity of organic reactions.