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Abstract An umpolung 1,4‐addition of aryl iodides to enals promoted by cooperative (terpy)Pd/NHC catalysis was developed that generates various bioactive β,β‐diaryl propanoate derivatives. This system is not only the first reported palladium‐catalyzed arylation of NHC‐bound homoenolates but also expands the scope of NHC‐induced umpolung transformations. A diverse array of functional groups such as esters, nitriles, alcohols, and heterocycles are tolerated under the mild conditions. This method also circumvents the use of moisture‐sensitive organometallic reagents.
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α,β-Dehydrogenation of esters with free O-H and N-H functionalities via allyl-palladium catalysis
A direct and selective method for the α,β-dehydrogenation of esters using palladium catalysis in the presence of free OH and NH functionalities is reported herein. Allyl-palladium catalysis allows for preservation of readily oxidizable functionalities such as amines and alcohols. Furthermore, an economical protocol using LDA was developed for the dehydrogenation of β-amino esters.
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- Award ID(s):
- 1653793
- PAR ID:
- 10090242
- Date Published:
- Journal Name:
- Tetrahedron
- ISSN:
- 1464-5416
- 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/10.1016/j.tet.2018.02.028.
