In this Account strategies using zeolites as media to achieve chiral induction are presented. Diastereomeric excesses as high as 90% and enantiomeric excesses up to 78% have been obtained with selected systems within zeolites. The same systems show no asymmetric induction in solution. Chiral induction is dependent on the alkali ions present in the zeolites. Alkali ions control not only the exte...

Flexible protected 1,3,4-trihydroxy-2-butanone is synthesized in high enantiomeric excesses by using asymmetric homo- and cross- acyloin coupling of aliphatic aldehydes catalyzed by benzaldehyde lyase.

Introduction: The finding of slight to significant enanti-omeric excesses for several indigenous amino acids in the Mur-chison and Murray CM-type meteorites [1-3] could point toward an exogenous origin of biological homochirality on the early Earth. UV circularly polarized light (UV-CPL) in the presolar cloud has been proposed as one possible source of the initial amino acid symmetry [4]. Howev...

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There is overwhelming evidence that meteorites bring a-methylated amino acids to earth with some L(S) enantiomeric excess. How does that get transferred into normal biological molecules? In this brief account, we show that an a-methylated amino acid, D(R)-a-methylvaline, can react with pyruvate and phenylpyruvate salts in dry mixtures to form alanine and phenylalanine with L enantiomeric excess...