The asymmetric synthesis of alkynyl and monofluoroalkenyl isoindolinones from N-methoxy benzamides and α,α-difluoromethylene alkynes is enabled by C-H activation with a chiral CpRh catalyst. Remarkably, product formation is solvent-dependent; alkynyl isoindolinones are afforded in MeOH (up to 86 % yield, 99.6 % ee) whereas monofluoroalkenyl isoindolinones are generated in PrCN (up to 98:2 Z/E, 93 % yield, 86 % ee). Mechanistic studies revealed chiral allene and E-configured alkenyl rhodium species as reaction intermediates. The latter is transformed into the corresponding Z-configured monofluoroalkene upon protonation in the PrCN system and into an alkyne by an unusual anti β-F elimination in the MeOH system. Notably, kinetic resolution processes occur in this reaction. Despite the moderate enantiocontrol for the formation of the chiral allene, the Z-monofluoroalkenyl isoindolinones and alkynyl isoindolinones were obtained in good enantiopurities by one or two sequential kinetic resolution processes.

An ew class of C 2-symmetric, chiral cyclopentadienyl ligand based on planar chiral ferrocene backbone was developed. As eries of its corresponding rhodium(I), iridium(I), and ruthenium(II) complexes were prepared as well. In addition, the rhodium(I) complexes were evaluated in the asymmetricc atalytic intramolecular amidoarylation of olefin-tethered benzamides via CÀHa ctivation. Figure 1. Cp ligands studied in asymmetric CÀHa ctivationreactions.

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The asymmetric synthesis of alkynyl and monofluoroalkenyl isoindolinones from N-methoxy benzamides and a,a-difluoromethylene alkynes is enabled by CÀHactivation with ac hiral CpRh III catalyst. Remarkably,p roduct formation is solvent-dependent;a lkynyl isoindolinones are afforded in MeOH (up to 86 %y ield, 99.6 %e e) whereas monofluoroalkenyl isoindolinones are generated in i PrCN (up to 98:2 Z/E, 93 %yield, 86 %ee). Mechanistic studies revealed chiral allene and E-configured alkenyl rhodium species as reaction intermediates.T he latter is transformed into the corresponding Z-configured monofluoroalkene upon protonation in the i PrCN system and into an alkyne by an unusual anti b-F elimination in the MeOH system. Notably,k inetic resolution processes occur in this reaction. Despite the moderate enantiocontrol for the formation of the chiral allene,t he Z-monofluoroalkenyl isoindolinones and alkynyl isoindolinones were obtained in good enantiopurities by one or two sequential kinetic resolution processes.Supportinginformation and the ORCID identification number(s) for the author(s) of this article can be found under: https://doi.