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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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HFIP as a versatile solvent in resorcin[ n ]arene synthesis
Herein, we present 1,1,1,3,3,3-hexafluoroisopropanol (HFIP) as an efficient solvent for synthesizing resorcin[n]arenes in the presence of catalytic amounts of HCl at ambient temperature and within minutes. Remarkably, resorcinols with electron-withdrawing groups and halogens, which are reported in the literature as the most challenging precursors in this cyclization, are tolerated. This method leads to a variety of 2-substituted resorcin[n]arenes in a single synthetic step with isolated yields up to 98%.
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- Award ID(s):
- 2302628
- PAR ID:
- 10630535
- Publisher / Repository:
- Beilstein-Institut
- Date Published:
- Journal Name:
- Beilstein Journal of Organic Chemistry
- Volume:
- 20
- ISSN:
- 1860-5397
- Page Range / eLocation ID:
- 2469 to 2475
- 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/10.3762/bjoc.20.211
