Metal chirality transmitters

Cinchona Alkaloids as Chirality Transmitters in Metal-Catalyzed Asymmetric Reductions... 

It would be required of an ideal chiral ligand to form chiral catalysts with as many metals as possible, which in turn are able to catalyze a great number of reactions and allow of broad substrate variability without loss of selectivity. There are no such universal ligands yet, but binaphthyls 1 come close to this ideal. The C2 axially-sym-metric biaryl frame is an excellent transmitter of chiral information, and the possibility of varying the coordination sites X (e. g. la-h) [2] enables the use of a wide range of metals. 

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