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Abstract Regio‐ and stereoselective distal allylic/benzylic C−H functionalization of allyl and benzyl silyl ethers was achieved using rhodium(II) carbenes derived from N‐sulfonyltriazoles and aryldiazoacetates as carbene precursors. The bulky rhodium carbenes led to highly site‐selective functionalization of less activated allylic and benzylic C−H bonds even in the presence of electronically preferred C−H bonds located α to oxygen. The dirhodium catalyst Rh2(S‐NTTL)4is the most effective chiral catalyst for triazole‐derived carbene transformations, whereas Rh2(S‐TPPTTL)4works best for carbenes derived from aryldiazoacetates. The reactions afford a variety of δ‐functionalized allyl silyl ethers with high diastereo‐ and enantioselectivity. The utility of the present method was demonstrated by its application to the synthesis of a 3,4‐disubstitutedl‐proline scaffold.
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Carbenes from cyclopropanated aromatics
The generation of saturated carbenes (A) and unsaturated carbenes (B) from cyclopropanated aromatic systems is reviewed.
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- Award ID(s):
- 1955874
- PAR ID:
- 10552772
- Publisher / Repository:
- Royal Society of Chemistry
- Date Published:
- Journal Name:
- Organic & Biomolecular Chemistry
- Volume:
- 21
- Issue:
- 48
- ISSN:
- 1477-0520
- Page Range / eLocation ID:
- 9482 to 9506
- 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/10.1039/d3ob01525d
