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Abstract Aryl tosylates are an attractive class of electrophiles for cross‐coupling reactions due to ease of synthesis, low price, and the employment of C−O electrophiles, however, the reactivity of aryl tosylates is low. Herein, we report the Ni‐catalyzed C(sp2)−C(sp3) Kumada cross‐coupling of aryl tosylates with primary and secondary alkyl Grignard reagents. The method delivers valuable alkyl arenes by cross‐coupling with challenging alkyl organometallics possessing β‐hydrogens that are prone to β‐hydride elimination and homo‐coupling. The reaction is catalyzed by an air‐ and moisture stable‐Ni(II) precatalyst. A broad range of electronically‐varied aryl tosylates, including bis‐tosylates, underwent this transformation, and many examples are suitable at mild room temperature conditions. The combination of Ar−X cross‐coupling with the facile Ar−OH activation/cross‐coupling strategy permits for orthogonal cross‐coupling with challenging alkyl organometallics. Furthermore, we demonstrate that the method operates with TON reaching 2000, which is one of the highest turnovers observed to date in Ni‐catalyzed cross‐couplings. magnified image
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Fluorocyclization of N ‐Propargyl Carboxamides by λ 3 ‐Iodane Catalysts with Coordinating Substituents
Abstract Aiming at the enhanced catalytic activity of fluoro‐λ3‐iodane generated from iodoarene precatalyst with Selectfluor and HF⋅pyridine, this study focused on the λ3‐iodanes bearing coordinating substituents. Compared to 4‐iodoanisole as a precatalyst of our previous method,N‐methyl‐2‐iodobenzamide or 2‐iodobenzamide worked well in the fluorocyclization ofN‐propargyl carboxamides to oxazoles. Control experiments suggest the equilibrium mixture of iodane‐amine complexes and cyclic iodane fluorides would be involved in the present catalysis. magnified image
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- Award ID(s):
- 1759798
- PAR ID:
- 10159778
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Synthesis & Catalysis
- Volume:
- 362
- Issue:
- 14
- ISSN:
- 1615-4150
- Format(s):
- Medium: X Size: p. 2997-3003
- Size(s):
- p. 2997-3003
- Sponsoring Org:
- National Science Foundation
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