(3+3)-Annulation of Carbonyl Ylides with Donor-Acceptor Cyclopropanes: Synergistic Dirhodium(II) and Lewis Acid Catalysis

Martin Petzold; Peter G Jones; Daniel B Werz

doi:10.1002/anie.201814409

(3+3)-Annulation of Carbonyl Ylides with Donor-Acceptor Cyclopropanes: Synergistic Dirhodium(II) and Lewis Acid Catalysis

Angew Chem Int Ed Engl. 2019 May 6;58(19):6225-6229. doi: 10.1002/anie.201814409. Epub 2019 Mar 13.

Authors

Martin Petzold¹, Peter G Jones², Daniel B Werz¹

Affiliations

¹ Technische Universität Braunschweig, Institute of Organic Chemistry, Hagenring 30, 38106, Braunschweig, Germany.
² Technische Universität Braunschweig, Institute of Inorganic and Analytical Chemistry, Hagenring 30, 38106, Braunschweig, Germany.

PMID: 30758111
DOI: 10.1002/anie.201814409

Abstract

The first (3+3)-annulation process of donor-acceptor cyclopropanes using synergistic catalysis is reported. The Rh₂ (OAc)₄ -catalyzed decomposition of diazo carbonyl compounds generated carbonyl ylides in situ. These 1,3-dipoles were converted with donor-acceptor cyclopropanes, activated by Lewis acid catalysis, to afford multiply substituted pyran scaffolds in high yield and diastereoselectivity. Extensive optimization studies enabled access to 9-oxabicyclo[3.3.1]nonan-2-one and 10-oxabicyclo[4.3.1]decen-2-ol cores, exploiting solvent effects on intermediate reactivity.

Keywords: carbonyl ylides; cycloaddition; cyclopropanes; donor-acceptor systems; synergistic catalysis.

Grants and funding

GAINBYSTRAIN/European Research Council/International