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Enantiomerically pure alpha-amino aldehydes from silylated alpha-amino acids.

ABSTRACT: The disilylation of alpha-amino acids 1 to provide 2 (72-87%) was achieved without racemization. An unprecedented borane-mediated semi-reduction strategy was devised to convert 2 to stable, isolable oxazaborolidines 3 (100%) which were hydrolyzed to provide 5 (49-60%) as pure, stable compounds. Analysis of the Mosher amides (8) of the gamma-amino esters 7 reveals that < or =2% racemization occurs in the 1 --> 8 conversions.

SUBMITTER: Soto-Cairoli B

PROVIDER: S-EPMC2563420 | biostudies-literature | 2008 Jan

REPOSITORIES: biostudies-literature

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Enantiomerically pure alpha-amino aldehydes from silylated alpha-amino acids.

Soto-Cairoli Buddy B de Pomar Jorge Justo JJ Soderquist John A JA

Organic letters 20071220 2

The disilylation of alpha-amino acids 1 to provide 2 (72-87%) was achieved without racemization. An unprecedented borane-mediated semi-reduction strategy was devised to convert 2 to stable, isolable oxazaborolidines 3 (100%) which were hydrolyzed to provide 5 (49-60%) as pure, stable compounds. Analysis of the Mosher amides (8) of the gamma-amino esters 7 reveals that < or =2% racemization occurs in the 1 --> 8 conversions. ...[more]

PMID: 18092797

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