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Asymmetric Synthesis of Spiropyrazolones by Sequential Organo- and Silver Catalysis.

ABSTRACT: A stereoselective one-pot synthesis of spiropyrazolones through an organocatalytic asymmetric Michael addition and a formal Conia-ene reaction has been developed. Depending on the nitroalkene, the 5-exo-dig-cyclization could be achieved by silver-catalyzed alkyne activation or by oxidation of the intermediate enolate. The mechanistic pathways have been investigated using computational chemistry and mechanistic experiments.

SUBMITTER: Hack D

PROVIDER: S-EPMC4725220 | biostudies-literature | 2016 Jan

REPOSITORIES: biostudies-literature

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Asymmetric Synthesis of Spiropyrazolones by Sequential Organo- and Silver Catalysis.

Hack Daniel D Dürr Alexander B AB Deckers Kristina K Chauhan Pankaj P Seling Nico N Rübenach Lukas L Mertens Lucas L Raabe Gerhard G Schoenebeck Franziska F Enders Dieter D

Angewandte Chemie (International ed. in English) 20151216 5

A stereoselective one-pot synthesis of spiropyrazolones through an organocatalytic asymmetric Michael addition and a formal Conia-ene reaction has been developed. Depending on the nitroalkene, the 5-exo-dig-cyclization could be achieved by silver-catalyzed alkyne activation or by oxidation of the intermediate enolate. The mechanistic pathways have been investigated using computational chemistry and mechanistic experiments. ...[more]

PMID: 26676875

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