Hydrogenation alkene, -NORPHOS

On the other hand, the preparation of TV-acetyl- and iV-benzoylferrocenylalanines 102 and 103 by enantioselective catalytic hydrogenation of the Z-alkenes 100 and 101 has been reported (Scheme 29).[6S1 In this case, a comparative study showed that among different chiral ligands for Rh, (+)- or (—)-Norphos were the ones giving the highest enantioselec-tivities (up to 94% ee) in the hydrogenation of 100. 

Enantioselective Hydrogenation of Alkene C=C Double Bonds. (S,S)-NORPHOS has been employed as a catalyst in combination with Rh(I) for enantioselective hydrogenation of alkene carbon-carbon double bonds in a variety of substrates. A representative sampling of these asymmmetric hydrogenations is shown in Table l. ... 

Table 1 Enantioselective hydrogenations of prochiral alkenes catalyzed by a transition-metal-NORPHOS complex ...

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See also in sourсe #XX -- [ ]

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