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Asymmetric Syntheses via Heterocyclic Intermediates, XLV. Asymmetric Synthesis of Diastereomerically and Enantiomerically Pure 3-Substituted (2R,3S)-serine Methyl Esters

✍ Scribed by Beulshausen, Tessa ;Groth, Ulrich ;Schöllkopf, Ulrich

Publisher
John Wiley and Sons
Year
1991
Tongue
English
Weight
297 KB
Volume
1991
Category
Article
ISSN
0947-3440

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✦ Synopsis

Abstract

The titanium derivative 2 of the bislactim ether 1 of cyclo(‐L‐Val‐Gly‐) reacts with aldehydes and ketones 3 highly diastereoselectively to give the syn‐addition products 4. Upon hydrolysis with diluted trifluoroacetic acid the compounds 4 yield besides methyl L‐valinate the (2__R__,3__S__)‐threo‐serine methyl esters 5.

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