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Enantioselective organocatalytic aminomethylation of aldehydes: a role for ionic interactions and efficient access to beta2-amino acids.

ABSTRACT: Organocatalytic Mannich addition of aldehydes to a formaldehyde-derived iminium species catalyzed by proline-derived chiral pyrrolidines provides beta-amino aldehydes with >/=90% ee. Mechanistic analysis of the proline-catalyzed reactions suggests that non-hydrogen-bonded ionic interactions at the Mannich reaction transition state can influence stereochemical outcome. The beta-amino aldehydes from our process bear a substituent adjacent to the carbonyl and can be efficiently converted to protected beta2-amino acids, which are important building blocks for beta-peptide foldamers that display useful biological activities.

SUBMITTER: Chi Y

PROVIDER: S-EPMC2715144 | biostudies-literature | 2006 May

REPOSITORIES: biostudies-literature

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Enantioselective organocatalytic aminomethylation of aldehydes: a role for ionic interactions and efficient access to beta2-amino acids.

Chi Yonggui Y Gellman Samuel H SH

Journal of the American Chemical Society 20060501 21

Organocatalytic Mannich addition of aldehydes to a formaldehyde-derived iminium species catalyzed by proline-derived chiral pyrrolidines provides beta-amino aldehydes with >/=90% ee. Mechanistic analysis of the proline-catalyzed reactions suggests that non-hydrogen-bonded ionic interactions at the Mannich reaction transition state can influence stereochemical outcome. The beta-amino aldehydes from our process bear a substituent adjacent to the carbonyl and can be efficiently converted to protect ...[more]

PMID: 16719457

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