Synlett 2018; 29(06): 717-722
DOI: 10.1055/s-0037-1609339
cluster
© Georg Thieme Verlag Stuttgart · New York

Ruthenium- and Rhodium-Catalyzed Ring-Opening Coupling Reactions of Cyclopropenones with Alkenes or Alkynes

Teruyuki Kondo*
a   Department of Energy and Hydrocarbon Chemistry, Graduate School of Engineering, Kyoto University, Nishikyo-ku, Kyoto 615-8510, Japan   Email: teruyuki@scl.kyoto-u.ac.jp
,
Ryosuke Taniguchi
a   Department of Energy and Hydrocarbon Chemistry, Graduate School of Engineering, Kyoto University, Nishikyo-ku, Kyoto 615-8510, Japan   Email: teruyuki@scl.kyoto-u.ac.jp
,
Yu Kimura
b   Research and Educational Unit of Leaders for Integrated Medical Systems, Center for the Promotion of Interdisciplinary Education and Research, Kyoto University, Nishikyo-ku, Kyoto 615-8510, Japan
› Author Affiliations
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Publication History

Received: 20 January 2018

Accepted after revision: 18 February 2018

Publication Date:
01 March 2018 (online)


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Published as part of the Cluster C–C Activation

Abstract

Ru3(CO)12-catalyzed divergent ring-opening coupling reactions of a cyclopropenone with methyl acrylate (an electron-deficient alkene) are developed. Under an argon atmosphere, a decarbonylative linear codimer is obtained, while cyclopentenones are obtained under carbon monoxide (20 atm) without decarbonylation. While ruthenium complexes show no catalytic activity for the ring-opening cocyclization of cyclopropenones with ethylene (20 atm) or bicyclo[2.2.1]hept-2-ene (2-norbornene), rhodium complexes, especially [RhCl(η4-1,5-cod)]2, show high catalytic activity for the desired cocyclization reactions to give the corresponding cyclopentenones in high yields and selectivities. In addition, [RhCl(η4-1,5-cod)]2 realizes the catalytic ring-opening co­cyclization of cyclopropenones with internal alkynes to give the corresponding cyclopentadienones. In all these reactions, ruthena- or rhodacyclobutenones are considered to be key intermediates, generated by strain-driven oxidative addition of a cyclopropenone C–C bond to an ­active ruthenium or rhodium species.

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