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Abstract [3+n]‐Cycloaddition reactions that employ donor‐acceptor cyclopropanes using either chiral catalysts and racemic cyclopropanes or achiral catalysts and chiral, non‐racemic, cyclopropanes have become useful transformations for the construction of carbocyclic and heterocyclic compounds, with both processes offering mechanistic and structural advantages in ring formation. Although the vast majority of asymmetric cycloaddition reactions of donor‐acceptor cyclopropanes have been performed with racemic cyclopropane compounds catalyzed by Lewis acids with chiral ligands, optically active cyclopropane compounds can serve the same role using Lewis acids without chiral ligands. This review covers the use of chiral catalysts with racemic donor‐acceptor cyclopropanes and the use of chiral non‐racemic donor‐acceptor cyclopropanes with achiral Lewis acid catalysts.
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Use of Unprecedented Intramolecular 1, 3‐Dipolar Cycloaddition Reaction in meso ‐Nitrile Oxide‐Containing BODIPYs as a New Pathway for the Preparation of Fused NIR Platforms
Abstract Meso‐nitrile oxide group in 1,7‐Diphenyl‐containing BODIPYs can be involved in highly unusual [3+2] intramolecular cycloaddition reaction with the formation of the dihydrobenzo[d]isoxazole‐containing BODIPYs. Oxidation of these compounds results in the formation of unprecedented either benzisoxazole‐ or benzo[b]azepine‐fused fully conjugated NIR absorbing BODIPYs. The photophysical properties and electronic structures of the target compounds were studied by an array of experimental and theoretical methods.
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- Award ID(s):
- 2153081
- PAR ID:
- 10508830
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Chemistry – A European Journal
- Volume:
- 30
- Issue:
- 35
- ISSN:
- 0947-6539
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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