Page 475 - Cascade_Biocatalysis_Integrating_Stereoselective_and_Environmentally_Friendly_Reactions

19.4 Combination of Substrate Synthesis and Derivatization Step(s) 451

O
Ph
N Ph
N H OH
H
(S)-ADH, buffer,
O (S,S)-91 (5 mol%), OH O i-PrOH 25% (v/v), OH OH
O rt NADH, rt
H +
Solvent-free Aqueous
Cl Cl Cl
89 90 conditions medium (1R,3S)-93
(4 equiv) (R)-92 >95% overall conversion
In situ-formed, 80% product-related
not isolated
conversion
dr(syn : anti) = 1 : 10
>99% ee
Scheme 19.28 One-pot synthesis of a 1,3-diol based on combination of organocatalytic aldol reaction under neat condi-
tions and alcohol dehydrogenase-catalyzed reduction.