We herein describe a highly diastereoselective rhodium(I)-catalyzed C−F bond functionalization of gem-difluoroalkenes with arylboronic acids. In contrast to previously developed Pd(II)-and Pd(0)-catalyzed methods, the Rh(I)/BINAP catalytic system enabled the C−F bond arylation of both trisubstituted β,βdifluorostyrenes and tetrasubstituted β,β-difluoroacrylates in >99:1 dr toward the synthesis of valuable monofluoroalkenes. Experimental and computational studies suggested a plausible migratory insertion/β-F elimination mechanism with the [Rh(I)-Ar] species.

Stereoselective synthesis of tetrasubstituted vinylsilanes is a challenging task. We herein report a novel palladium(0)-catalyzed defluorosilylation of β,β-difluoroacrylates to access tetrasubstituted vinylsilanes containing the monofluoroalkene motif in excellent diastereoselectivities (>99:1). This is our first example of C− heteroatom bond formation from the C−F bond under such a Pd catalytic manifold.

We herein describe selective C–F bond functionalizations of tetrasubstituted gem-difluoroalkenes and trisubstituted monofluoroalkenes using Grignard reagents without the transition metal catalyst. β,β-Difluoroacrylates react with Grignard reagents under mild conditions to afford tetrasubstituted (E)-β-monofluoroacrylates. Experimental and computational studies revealed that the selectivity stems from the intrinsic reactivity difference between the (E)- and (Z)-isomers toward excess Grignard reagent, which leads to the resolution of the two products.

We herein describe a highly selective Rh­(I)-catalyzed defluorinative coupling of boronic acids with (E)-β-monofluoroacrylates. In contrast to previous methods, the trisubstituted (Z)-alkene products were obtained in excellent dr with an inversion of double bond geometry. Experimental and computational studies established that Rh­(I)-facilitated β-F elimination is favored over competing β-H elimination and protodemetalation.

We herein describe a nucleophilic vinylic substitution (SNV) of trisubstituted monofluoroalkenes with excellent stereocontrol (d.r. > 99:1). Starting from (E)-β-monofluoroacrylates, various trisubstituted (E)-alkenes containing O/N/S-substituent groups at the vinylic position can be obtained under simple conditions. Furthermore, (E,E)-divinyl ethers can be generated through dimerization of the monofluoroalkenes, triggered by adventitious water in the reaction mixture.