Abstract A palladium‐catalyzed dearomativesyn‐1,4‐oxyamination protocol using non‐activated arenes has been developed. This one‐pot procedure utilizes arenophile chemistry, and the correspondingpara‐cycloadducts are treated with oxygen nucleophiles via formal allylic substitution, providing direct access tosyn‐1,4‐oxyaminated products. The reaction conditions permit a range of arenes, as well as different O‐nucleophiles, such as oximes and benzyl alcohols. Moreover, this process was established in an asymmetric fashion, delivering products with high enantioselectivity. The dearomatized products are amenable to a multitude of further derivatizations ranging from olefin chemistry to C−H activation, giving rise to a diverse set of new functionalities. Overall, this dearomative functionalization offers rapid and controlled formation of molecular complexity, enabling straightforward access to functionalized small molecules from simple and readily available arenes.
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Nickel-catalyzed arylative substitution of homoallylic alcohols
Direct coupling of unactivated alcohols remains a challenge in synthetic chemistry. Current approaches to cross-coupling of alcohol-derived electrophiles often involve activated alcohols such as tosylates or carbonates. We report the direct arylative substitution of homoallylic alcohols catalyzed by a nickel-bisphosphine complex as a facile method to generate allylic arenes. These reactions proceed via formation of an allylic alcohol intermediate. Subsequent allylic substitution with arylboroxine nucleophiles enables the formation of a variety of allylic arenes. The presence of p -methoxyphenylboronic acid is crucial to activate the allylic alcohol to achieve high product yields.
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- Award ID(s):
- 1955529
- PAR ID:
- 10400434
- Date Published:
- Journal Name:
- Chemical Science
- Volume:
- 13
- Issue:
- 39
- ISSN:
- 2041-6520
- Page Range / eLocation ID:
- 11607 to 11613
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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