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Abstract Propargylic ethers serve as useful intermediates for the synthesis of a variety of complex targets. However, propargylic substitution of prefunctionalized alkyne starting materials remains the dominant method for the synthesis of propargyl ethers, while direct etherification of simple alkynes via propargylic C−H functionalization remains largely underreported. Herein, we report an organometallic umpolung approach for iron‐mediated C−H propargylic etherification. A telescopic protocol for iron‐mediated C−H deprotonation followed by mild oxidative coupling with alcohols enabled the use of simple or functionalized alkynes for the expedient synthesis of propargylic ethers with excellent functional group compatibility, chemoselectivity and regioselectivity.
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Intermolecular Allylic C−H Etherification of Internal Olefins
Abstract Herein we report on the development of an oxidative allylic C−H etherification reaction, utilizing internal olefins and alcohols as simple precursors. Key advances include the use of RhCp* complexes to promote the allylic C−H functionalization of internal olefins and the compatibility of the oxidative conditions with oxidatively sensitive alcohols, enabling the direct etherification reaction. Preliminary mechanistic studies, consistent with C−H functionalization as the rate determining step, are presented.
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- Award ID(s):
- 1700982
- PAR ID:
- 10077231
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Angewandte Chemie International Edition
- Volume:
- 57
- Issue:
- 45
- ISSN:
- 1433-7851
- Page Range / eLocation ID:
- p. 14911-14915
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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