A New Principle in Combinatorial Asymmetric Transition-Metal Catalysis: Mixtures of Chiral Monodentate P Ligands

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

Mixtures of monodentate P-ligands as a means to control the diastereoselectivity in Rh-catalyzed hydrogenation of chiral alkenes

The previously reported concept of using mixtures of monodentate ligands in a combinatorial manner in order to influence enantio- or regioselectivity of transition metal catalyzed processes has been extended to include diastereoselectivity. Accordingly, 1,2- and 1,3-asymmetric induction in the Rh-catalyzed hydrogenation of a chiral allylic alcohol and a chiral homo-allylic alcohol has been stud...

Tandem rhodium catalysis: exploiting sulfoxides for asymmetric transition-metal catalysis.

Sulfoxides are uncommon substrates for transition-metal catalysis due to their propensity to inhibit catalyst turnover. In a collaborative effort with Ken Houk, we developed the first dynamic kinetic resolution (DKR) of allylic sulfoxides using asymmetric rhodium-catalyzed hydrogenation. A detailed mechanistic analysis of this transformation using both experimental and theoretical methods revea...

Ferrocene-Based Chiral Phosphine-Triazines: A New Family of Highly Efficient P,N Ligands for Asymmetric Catalysis

The presence of the additional heterocyclic nitrogen atoms in chiral P,N ligands has an important influence on the asymmetric catalysis, and a clear trend was observed in the present research that the enantioselectivity and reactivity were significantly increased by raising the number of heterocyclic nitrogen atoms in these P,N ligands. Through finely tuning the number of heterocyclic nitrogen ...

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...