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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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Rhodium/Gold Dual Catalysis in Carbene sp 2 C−H Functionalization/Conia‐ene Cascade for the Stereoselective Synthesis of Diverse Spirocarbocycles
Abstract A Rh(II)/Au(I) catalyzed carbene cascade approach for the stereoselective synthesis of diverse spirocarbocycles is described. The cascade reaction involves a rhodium carbene initiatedsp2C−H functionalization followed by a gold catalyzed Conia‐ene cyclization. The cascade reaction accommodates a variety of aryl substituents as well as ring sizes and proceeds with high diastereoselectivity providing access to diverse spirocarbocycles. magnified image
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- Award ID(s):
- 1753187
- PAR ID:
- 10116047
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Synthesis & Catalysis
- Volume:
- 361
- Issue:
- 12
- ISSN:
- 1615-4150
- Format(s):
- Medium: X Size: p. 2951-2958
- Size(s):
- p. 2951-2958
- Sponsoring Org:
- National Science Foundation
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