Amide-Rhodium Complexes as Catalysts

Abley and McQuillin (44) have reported asymmetric homogeneous hydrogenations catalyzed by rhodium complexes of chiral amides. In initial experiments the catalyst was generated in situ by treating trichlorotripyridylrhodium(III) with sodium borohydride in an optically active amide solvent (Fig. 20). In later work a 5% solution of the amide in diethylene glycol monoethyl ether was used and products with the same optical purities were obtained. This evidence indi- 

Synthesis of rhodium catalysts containing chiral amide ligands. 

Although very little is known about the mechanism of such hydrogenations, Abley and McQuillin assumed that hydrogen transfer occurred in a stepwise fashion. It was claimed that the configuration of the methyl 3-phenylbutanoate 

Chiral amide ligands used in homogeneous hydrogenation reactions. 

Hydrogenation of (Ej- and (Z)-Methyl-p-methylcinnamate with Rhodium (IIIj-Borohydride Complexes of Chiral Amides 

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