Page 229 - Catalysts for Fine Chemical Synthesis Vol 1 - Robert & Poignant

employment of catalysts working in tandem 217

R 2
OR 3
R 1 HN
OH O

Table 13.1 Sequential asymmetric hydrogenation of g-(acylamino)-g, d-
unsaturated-b-keto esters catalysed by Rh[(cod)(S)-BiNAP] CIO ÿ and
‡
4
RuBr 2 [(S)-BiNAP].
Solvent R 1 R 2 R 3 Yield % ee %
EtOH Ac Ph Et 99 >95
MeOH Ac Ph Me 99 >95
t-BuOH Ac Ph t-Bu no reaction ±
Et Boc Ph Et 99 >95
Et Ac 4-Cl-C 6 H 4 Et 90 >95

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