Transition-metal-catalyzed decarbonylation reactions of aliphatic carboxylic acids produce olefins via one carbon degradation. Recently, tremendous progress has been made in the development of new protocols for the synthesis of linear olefins by the formal acyl C–O activation mechanism of ubiquitous carboxylic acids. Various transition metals including nickel, palladium, iridium and iron have been shown to catalyze the reaction and achieve excellent yields and selectivity. The use of new ligand systems has resulted in unprecedented control of selectivity of elementary steps in the catalytic cycle. The development of new acyl precursors expands the access to α-olefins and offers promising perspectives for applications in preparative organic synthesis. In this article, we highlight the recent noteworthy developments in the transition-metal-catalyzed decarbonylation of carboxylic acids and discuss future challenges in this field.
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Scalable Electrochemical Decarboxylative Olefination Driven by Alternating Polarity**
Abstract A mild, scalable (kg) metal‐free electrochemical decarboxylation of alkyl carboxylic acids to olefins is disclosed. Numerous applications are presented wherein this transformation can simplify alkene synthesis and provide alternative synthetic access to valuable olefins from simple carboxylic acid feedstocks. This robust method relies on alternating polarity to maintain the quality of the electrode surface and local pH, providing a deeper understanding of the Hofer‐Moest process with unprecedented chemoselectivity.
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- Award ID(s):
- 2002158
- PAR ID:
- 10467363
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- Angewandte Chemie International Edition
- ISSN:
- 1433-7851
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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