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Towards an Asymmetric Organocatalytic ?-Azidation of ?-Ketoesters.

ABSTRACT: Detailed investigations concerning the organocatalytic (asymmetric) ?-azidation of prochiral ?-ketoesters were carried out. It was shown that the racemic version of such a reaction can either be carried out under oxidative conditions using TMSN? as the azide-source with quaternary ammonium iodides as the catalysts, or by using hypervalent iodine-based electrophilic azide-transfer reagents with different organocatalysts. In addition, the latter strategy could also be carried out with modest enantioselectivities when using simple cinchona alkaloid catalysts, albeit with relatively low yields.

SUBMITTER: Tiffner M

PROVIDER: S-EPMC6100502 | biostudies-literature | 2018 May

REPOSITORIES: biostudies-literature

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Towards an Asymmetric Organocatalytic α-Azidation of β-Ketoesters.

Tiffner Maximilian M Stockhammer Lotte L Stockhammer Lotte L Schörgenhumer Johannes J Röser Katharina K Waser Mario M

Molecules (Basel, Switzerland) 20180511 5

Detailed investigations concerning the organocatalytic (asymmetric) α-azidation of prochiral β-ketoesters were carried out. It was shown that the racemic version of such a reaction can either be carried out under oxidative conditions using TMSN₃ as the azide-source with quaternary ammonium iodides as the catalysts, or by using hypervalent iodine-based electrophilic azide-transfer reagents with different organocatalysts. In addition, the latter strategy could also be carried out with modest enant ...[more]

PMID: 29751597

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