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Microwave-assisted Intramolecular Dehydrogenative Diels-Alder Reactions for the Synthesis of Functionalized Naphthalenes/Solvatochromic Dyes
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Ni-Catalyzed Reductive Ring Contraction via Desulfurative Cross-Coupling
1Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford St., Cambridge, Massachusetts 02138, United States.
Journal of the American Chemical Society
|July 10, 2025
Summary
This study introduces a novel catalytic method for synthesizing complex heterocycles by removing sulfur atoms from C-S-C bonds. The new nickel-catalyzed desulfurization operates under mild conditions, offering a significant advancement in synthetic chemistry.
Area of Science:
- Organic Chemistry
- Synthetic Chemistry
- Heterocyclic Chemistry
Background:
- Construction of carbon-carbon (C-C) bonds via sulfur atom extrusion from C-S-C motifs is crucial for synthesizing complex heterocycles.
- Existing homogeneous metal systems for desulfurization require harsh conditions and lack catalytic turnover due to stable sulfido complex formation.
Purpose of the Study:
- To develop a mild, catalytic method for desulfurization to form C-C bonds.
- To enable efficient synthesis of a broad range of fused heterocycles.
Main Methods:
- Utilized an accessible nickel (Ni) precatalyst.
- Employed inexpensive additives.
- Performed the reaction under mild conditions.
Main Results:
- Achieved rapid access to a wide scope of fused heterocycles.
- Demonstrated a catalytic solution for desulfurization, overcoming limitations of previous methods.
- Preliminary mechanistic studies provided insights into C-S bond activation and additive effects.
Conclusions:
- The developed Ni-catalyzed desulfurization offers an efficient and mild route to complex heterocycles.
- The method presents a significant improvement over existing desulfurization techniques.
- Understanding the mechanism aids in further optimization and application of this transformation.
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