Application of Chiral Olefin Ligands in Asymmetric Catalysis

Chiral olefin ligands-new "spectators" in asymmetric catalysis.

Ion-paired chiral ligands for asymmetric palladium catalysis.

Conventional chiral ligands rely on the use of a covalently constructed, single chiral molecule embedded with coordinative functional groups. Here, we report a new strategy for the design of a chiral ligand for asymmetric transition-metal catalysis; our approach is based on the development of an achiral cationic ammonium-phosphine hybrid ligand paired with a chiral binaphtholate anion. This ion...

Asymmetric synthesis of axially chiral anilides by Pd-catalyzed allylic substitutions with P/olefin ligands.

As an attractive class of non-biaryl atropisomeric compounds, C-N axially chiral anilides have received considerable attention, and several methods have been successfully developed for their synthesis. Pd-catalyzed asymmetric allylic amination was proved to be an effective approach for the chiral anilide synthesis, although only moderate enantioselectivity and relatively narrow substrate scope ...

Amino acids as chiral anionic ligands for ruthenium based asymmetric olefin metathesis.

Several amino acid ligands were introduced into the Hoveyda-Grubbs 2nd generation complex by a facile anionic ligand exchange. The chiral pre-catalysts obtained displayed enantioselectivity in asymmetric ring-closing and ring-opening cross-metathesis reactions. Reduction of the lability of the carboxylate ligands was found to be cardinal for improving the observed enantiomeric product enrichment.

Chiral allene-containing phosphines in asymmetric catalysis.

We demonstrate that allenes, chiral 1,2-dienes, appended with basic functionality can serve as ligands for transition metals. We describe an allene-containing bisphosphine that, when coordinated to Rh(I), promotes the asymmetric addition of arylboronic acids to α-keto esters with high enantioselectivity. Solution and solid-state structural analysis reveals that one olefin of the allene can coor...