The first cobalt‐catalyzed cross‐coupling of aryl tosylates with alkyl and aryl Grignard reagents is reported. The catalytic system uses CoF3and NHCs (NHC=N‐heterocyclic carbene) as ancillary ligands. The reaction proceeds via highly selective C−O bond functionalization, leading to the corresponding products in up to 98 % yield. The employment of alkyl Grignard reagents allows to achieve a rare C(sp2)−C(sp3) cross‐coupling of C−O electrophiles, circumventing isomerization and β‐hydride elimination problems. The use of aryl Grignards leads to the formation of biaryls. The C−O cross‐coupling sets the stage for a sequential cross‐coupling by exploiting the orthogonal selectivity of the catalytic system.
Sulfones as Synthetic Linchpins: Transition-Metal-Free sp 3 -sp 2 and sp 2 -sp 2 Cross-Couplings Between Geminal Bis(sulfones) and Organolithium Compounds
- NSF-PAR ID:
- 10059550
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Chemistry - A European Journal
- Volume:
- 24
- Issue:
- 36
- ISSN:
- 0947-6539
- Page Range / eLocation ID:
- 9066 to 9074
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract -
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