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Palladium-catalyzed Suzuki–Miyaura cross-coupling or aryl halides is widely employed in the synthesis of many important molecules in synthetic chemistry, including pharmaceuticals, polymers and functional materials. Herein, we disclose the first palladium-catalyzed decarbonylative Suzuki–Miyaura cross-coupling of amides for the synthesis of biaryls through the selective activation of the N–C(O) bond of amides. This new method relies on the precise sequence engineering of the catalytic cycle, wherein decarbonylation occurs prior to the transmetallation step. The reaction is compatible with a wide range of boronic acids and amides, providing valuable biaryls in high yields (>60 examples). DFT studies support a mechanism involving oxidative addition, decarbonylation and transmetallation and provide insight into high N–C(O) bond activation selectivity. Most crucially, the reaction establishes the use of palladium catalysis in the biaryl Suzuki–Miyaura cross-coupling of the amide bond and should enable the design of a wide variety of cross-coupling methods in which palladium rivals the traditional biaryl synthesis from aryl halides and pseudohalides.
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C–O-Selective Cross-Coupling of Chlorinated Phenol Derivatives
Abstract Chemoselective cross-coupling of phenol derivatives is valuable for generating products that retain halides. Here we discuss recent developments in selective cross-couplings of chloroaryl phenol derivatives, with a particular focus on reactions of chloroaryl tosylates. The first example of a C–O-selective Ni-catalyzed Suzuki–Miyaura coupling of chloroaryl tosylates is discussed in detail. 1 Introduction 2 Density Functional Theory Studies on Oxidative Addition at Nickel(0) 3 Stoichiometric Oxidative Addition Studies 4 Development of a Tosylate-Selective Suzuki Coupling 5 Conclusion and Outlook
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- Award ID(s):
- 1848090
- PAR ID:
- 10314741
- Date Published:
- Journal Name:
- Synlett
- Volume:
- 32
- Issue:
- 15
- ISSN:
- 0936-5214
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1055/a-1503-6330
