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Abstract A Pd‐catalyzed heterocyclization/carbonylation/arylation cascade reaction between β,γ‐unsaturated N−Ts hydrazones and commercially available arylboronic acids as coupling partners is described, producing 2‐pyrazoline‐ketone derivatives in 11–78% yield. A detailed statistical analysis of reactivity patterns of boronic acids provided key information about the limitations of the method, highlighting the challenges of degradation pathways. Our methodology offers a tool for synthesizing diverse 2‐pyrazoline‐ketone derivatives, expanding the toolbox of accessible N−N‐heterocycles.
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Advances in Selected Heterocyclization Methods
Abstract This Account summarizes efforts in our group toward synthesis of heterocycles in the past decade. Selected examples of transannulative heterocyclizations, intermediate construction of reactive compounds en route to these important motifs, and newer developments of a radical approach are outlined. 1 Introduction 2 Transannulative Heterocyclization 2.1 Rhodium-Catalyzed Transannulative Heterocyclization 2.2 Copper-Catalyzed Transannulative Heterocyclization 3 Synthesis of Heterocycles from Reactive Precursors 3.1 Synthesis of Heterocycles from Diazo Compounds 3.2 Synthesis of Heterocycles from Alkynones 4 Radical Heterocyclization 4.1 Light-Induced Radical Heterocyclization 4.2 Light-Free Radical Heterocyclization 7 Conclusion
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- Award ID(s):
- 1955663
- PAR ID:
- 10473948
- Publisher / Repository:
- Thieme
- Date Published:
- Journal Name:
- Synlett
- Volume:
- 34
- Issue:
- 13
- ISSN:
- 0936-5214
- Page Range / eLocation ID:
- 1554 to 1562
- 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/10.1055/s-0042-1751429
