Rhodium ferrocenylphosphine complex, chiral

Asymmetric hydrogenation of a,fi-unsa turated acids.1 2- Aryl-3-methyl-2-bu-tenoic acids (2) undergo highly stereoselective hydrogenation catalyzed by a complex of rhodium with the chiral (aminoalkyl)ferrocenylphosphine (1), but not with... 

In Section 4, it is described that chlorotris(triphenylphosphine)rhodium(I) (7) is quite an effective catalyst for the hydrosilylation of carbonyl compounds. For this reason, extensive studies on asymmetric hydrosilylation of prochiral ketones to date have been based on employing rhodium(I) complexes with chiral phosphine ligands. The catalysts all prepared in situ are rhodium(I) complexes of the type, (BMPP>2Rh(S)a (8) [40] and (DIOP)Rh(S)Cl (6) [41], and a cationic rhodium(III) complex, [(BMPP)2lUiH2(S)2] Q04 (5) [42], where S represents a solvent molecule. An interesting polymer-supported rhodium complex (V) [41], and several chiral ferrocenylphosphines [43], recently developed as chiral ligands, have also been employed for asymmetric hydrosilylation of ketones. Included in this section also are selective asymmetric hydrosilylation of a,0-unsaturated carbonyl compounds and of certain keto esters. 

TABLE 6-1. Asymmetric Hydrogenation of Trisubstituted Acrylic Acids Catalyzed by Chiral Ferrocenylphosphine-Rhodium Complexes... 

Hamada s group has developed the rhodium-catalysed asymmetric hydrogenation of a-amino-)S-ester hydrochlorides via DKR. The reaction proceeded with the catalyst derived from a rhodium complex and a chiral ferrocenylphosphine under hydrogen in the presence of sodium acetate in acetic acid to alford the corresponding awti-jS-hydroxy-a-amino esters with 58-83% ee in a diastereomeric ratio of 92 8 to 97 3 (Scheme 2.83). 

Hayashi, T., T. Mise, S. Mitachi, K. Yamamoto, and M. Kumada Asymmetric Hydrogenation Catalyzed by a Chiral Ferrocenylphosphine-Rhodium-Complex. Tetrahedron Letters 1976, 1133. 

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