Metal-catalyzed asymmetric processes offer one of the most straightforward ways to introduce stereogenic centers Hence, the development of novel chiral ligands that can effectively induce asymmetry in reactions is crucial in modern organic synthesis While many established chiral ligands bind to a metal through heteroatoms, structures that coordinate to metals through carbon atoms have received little attention so far Here, we highlight the increasing number of such chiral chelating olefin ligands as well as their application in a variety of metal-catalyzed transformations

Chiral olefins as steering ligands in asymmetric catalysis.

New Palladium Carbene Catalysts for the Heck Reaction of Aryl Chlorides in Ionic Liquids

New processes for the selective production of 1-octene

Organopalladium complexes containing palladiumpalladium bonds

A highly efficient catalyst for the telomerization of 1,3-dienes with alcohols: first synthesis of a monocarbenepalladium(0)-olefin complex.

The complexes (cod)MCl2 (M = Pd, Pt; cod = cis,cis-1,5-cyclooctadiene) react with Li2(cot) (cot = cyclooctatetraene) in a 1,6-diene/diethyl ether mixture (1,6-diene = hepta-1,6-diene, diallyl ether, dvds (1,3-divinyl-1,1,3,3-tetramethyldisiloxane)) to afford the isolated homoleptic dinuclear Pd0 and Pt0 compounds Pd2(C7H12)3 (1), Pd2(C6H10O)3·C6H10O (2‘; 2:  Pd2(C6H10O)3), Pd2(dvds)3 (3), and Pt2(C7H12)3 (4). When 1−4 are treated with additional 1,6-diene the equally homoleptic but mononuclear derivatives of type M(1,6-diene)2 (5−8) and with ethene the mixed alkene complexes (C2H4)M(1,6-diene) (9−12) are obtained in solution. Complexes 1−12 react with donor ligands such as phosphanes, phosphites, or tBuNC to give isolated complexes of types L−M(1,6-diene) (13−41), which have also been prepared by other routes. In all complexes the metal centers are TP-3 coordinated:  complexes 1−4 contain chelating and bridging 1,6-diene ligands, whereas the other complexes contain a chelating 1,6-diene ligand and an η2-a...

Günter Cestaric

Papers

1,6-Diene Complexes of Palladium(0) and Platinum(0): Highly Reactive Sources for the Naked Metals and [L−M0] Fragments

Hepta-1,6-diene and diallyl ether complexes of palladium(0) and platinum(0):a route to L–M(alkene)2 complexes containing non-activated alkenes