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Rh-catalyzed Reagent-Free Ring Expansion of Cyclobutenones and Benzocyclobutenones.

ABSTRACT: Here we report a reagent-free rhodium-catalyzed ring-expansion reaction via C-C cleavage of cyclobutenones. A variety of poly-substituted cyclopentenones and 1-indanones can be synthesized from simple cyclobutenones and benzocyclobutenones. The reaction condition is near pH neutral without additional oxidants or reductants. The potential for developing a dynamic kinetic asymmetric transformation of this reaction has also been demonstrated. Further study supports the proposed pathway involving Rh-insertion into the cyclobutenone C-C bond, followed by β-hydrogen elimination, olefin insertion and reductive elimination.

SUBMITTER: Chen PH

PROVIDER: S-EPMC5201212 | biostudies-literature | 2015 Oct

REPOSITORIES: biostudies-literature

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Rh-catalyzed Reagent-Free Ring Expansion of Cyclobutenones and Benzocyclobutenones.

Chen Peng-Hao PH Sieber Joshua J Senanayake Chris H CH Dong Guangbin G

Chemical science 20150710 10

Here we report a reagent-free rhodium-catalyzed ring-expansion reaction via C-C cleavage of cyclobutenones. A variety of poly-substituted cyclopentenones and 1-indanones can be synthesized from simple cyclobutenones and benzocyclobutenones. The reaction condition is near pH neutral without additional oxidants or reductants. The potential for developing a dynamic kinetic asymmetric transformation of this reaction has also been demonstrated. Further study supports the proposed pathway involving Rh ...[more]

PMID: 28042458

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