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A simple procedure for the preparation of enantiopure ethyl α-hydroxyalkyl ketones

✍ Scribed by Ricardo Martín; Oscar Pascual; Pedro Romea; Roser Rovira; Fèlix Urpí; Jaume Vilarrasa

Publisher
Elsevier Science
Year
1997
Tongue
French
Weight
286 KB
Volume
38
Category
Article
ISSN
0040-4039

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✦ Synopsis

Amides derived from pyrrolidine and methyl (S)-lactate, methyl (S)-2-hydroxy-3-phenylpropanoate, or methyl (S)-2-hydroxy-3-methylbutanoate, after O-benzylation and O-silylation have been treated with EtLi or EtMgC1 under suitable conditions, to give excellent overall yields of enantiopure ethyl ketones. The chelating ability of ct-OBn amides (and even of a-O-TBS amides, which has been demonstrated by NMR to be better than that of N-OMe amides) accounts for the performance of the approach.

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