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Abstract The development of a platinum‐catalyzed desaturation of cyclic ketones to their conjugated α,β‐unsaturated counterparts is reported in this full article. A unique diene‐platinum complex was identified to be an efficient catalyst, which enables direct metal‐enolate formation. The reaction operates under mild conditions without using strong bases or acids. Good to excellent yields can be achieved for diverse and complex scaffolds. A wide range of functional groups, including those sensitive to acids, bases/nucleophiles, or palladium species, are tolerated, which represents a distinct feature from other known desaturation methods. Mechanistically, this platinum catalysis exhibits a fast and reversible α‐deprotonation followed by a rate‐determining β‐hydrogen elimination process, which is different from the prior Pd‐catalyzed desaturation method. Promising preliminary enantioselective desaturation using a chiral‐diene‐platinum complex has also been obtained.
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Synthesis of α,β-unsaturated epoxy ketones utilizing a bifunctional sulfonium/phosphonium ylide
Herein, a new protocol for rapid synthesis of α,β-unsaturated epoxy ketones utilizing a bifunctional sulfonium/phosphonium ylide is described. This approach comprises two sequential chemoselective reactions between sulfonium and phosphonium ylides and two distinct aldehydes, which allows for the rapid construction of a variety of unsymmetric α,β-unsaturated epoxy ketones. This methodology allows the rapid construction of the core reactive functionality of a family of lipid peroxidation products, the epoxyketooctadecenoic acids, but can be further broadly utilized as a useful synthon for the synthesis of natural products, particularly those derived from oxidized fatty acids. Accordingly, a protocol utilizing this approach to synthesize the epoxyketooctadecenoic acid family of molecules is described.
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- Award ID(s):
- 1904530
- PAR ID:
- 10315689
- Date Published:
- Journal Name:
- Chemical Communications
- Volume:
- 57
- Issue:
- 58
- ISSN:
- 1359-7345
- 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/10.1039/d1cc02475b
