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This article describes the first enantioselective synthesis of the Tasmanian marine alkaloid (+)-cylindricine B. The concise construction of the compound hinged on dearomative retrosynthetic logic combined with a tactical advance in the generation of congested, cyclic, alpha-tertiary amine centers. The scope of this key coupling reaction was explored in addition to providing a synthetic application for Cu-catalyzed enantioselective dearomatization of N-acyl-pyridiniums. The synthesis proceeds in five or six steps from commercially available starting materials.
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Synthesis of N-Acyl Pyrroles and Isoindoles from Oxime Ester Precursors via Transition-Metal-Catalyzed Iminocarboxylation
Abstract We describe Pt(II)- and Fe(III)-catalyzed iminocarboxylations of oxime esters conjugated with 1,3-enyne and an ortho-alkynylarene moiety, followed by a spontaneous O→N acyl migration of the enol carboxylate intermediate to generate N-acyl pyrroles and isoindoles. The reaction scope for pyrrole synthesis is general, whereas the formation of isoindoles has a relatively narrow scope because of their instability.
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- Award ID(s):
- 2055055
- PAR ID:
- 10431471
- Date Published:
- Journal Name:
- Synlett
- Volume:
- 34
- Issue:
- 12
- ISSN:
- 0936-5214
- Page Range / eLocation ID:
- 1487 to 1491
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1055/s-0042-1751377
