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Asymmetric Syntheses via Heterocyclic Intermediates, XLIV. Asymmetric Synthesis of Methyl (2R,3S)-2-Amino-3-cyclopropyl-3-hydroxyalkanoates via Diastereoselective Simmons-Smith Reactions

✍ Scribed by Groth, Ulrich ;Schöllkopf, Ulrich ;Tiller, Thomas

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

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✦ Synopsis

Abstract

The cyclopropanation of the bislactim ethers 3 with diiodomethanes and diethylzinc proceeds in good yields and with high diastereoselectivities, affording the cyclopropyl bislactim ethers 6. Protection of the hydroxy group and subsequenthydrolysis furnish virtually enantiomerically and diastereomerically pure methyl (2__R__,3__S__)‐2‐amino‐3‐cyclopropyl‐3‐hydroxyalkanoates 8. The bislactim ethers of type 3 are obtained by a known method diastereomerically pure, starting from the bislactim ether of cyclo(‐L‐Val‐Gly‐).

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