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Asymmetric syntheses of three-membered heterocycles using chiral amide-based ammonium ylides.

ABSTRACT: The use of carbonyl-stabilised ammonium ylides to access chiral glycidic amides and the corresponding aziridines has so far been limited to racemic trans-selective protocols. We herein report the development of an asymmetric approach to access such compounds with high levels of stereoselectivity using easily accessible chiral auxiliary-based ammonium ylides. The use of phenylglycinol as the chiral auxiliary was found to be superior to Evans or pseudoephedrine-based auxiliaries resulting in good to excellent stereoselectivities in both, epoxidation and aziridination reactions.

SUBMITTER: Pichler M

PROVIDER: S-EPMC4323751 | biostudies-literature | 2015 Feb

REPOSITORIES: biostudies-literature

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Asymmetric syntheses of three-membered heterocycles using chiral amide-based ammonium ylides.

Pichler Mathias M Novacek Johanna J Robiette Raphaël R Poscher Vanessa V Himmelsbach Markus M Monkowius Uwe U Müller Norbert N Waser Mario M

Organic & biomolecular chemistry 20150201 7

The use of carbonyl-stabilised ammonium ylides to access chiral glycidic amides and the corresponding aziridines has so far been limited to racemic trans-selective protocols. We herein report the development of an asymmetric approach to access such compounds with high levels of stereoselectivity using easily accessible chiral auxiliary-based ammonium ylides. The use of phenylglycinol as the chiral auxiliary was found to be superior to Evans or pseudoephedrine-based auxiliaries resulting in good ...[more]

PMID: 25521410

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