Direct Conversion of Nitriles into Alkene "Isonitriles"
1Department of Chemistry, Drexel University, 32 S. 32 nd Street, Philadelphia, PA, 19104-2875, USA.
Angewandte Chemie (International Ed. in English)
|October 26, 2016
Summary
Researchers developed a direct, one-pot synthesis for alkene isocyanides, valuable intermediates for creating substituted naphthalenes. This method efficiently produces challenging aromatic compounds via a novel cycloaddition reaction.
Area of Science:
- Organic Chemistry
- Synthetic Chemistry
Background:
- Alkene isocyanides are valuable synthetic intermediates.
- Direct synthesis of aromatic alkene isocyanides is challenging.
Purpose of the Study:
- To develop an efficient and direct synthetic route to alkene isocyanides.
- To utilize these isocyanides for the synthesis of substituted naphthalenes.
Main Methods:
- A one-pot sequence involving RLi addition to nitriles, trapping with isopropylformate, and dehydration with phosphoryl chloride.
- Copper(I) cyanide (CuCN) catalysis for formyl imine to N-formyl enamine equilibration.
- A [4+2]-type cycloaddition/1,3-H shift/decyanation sequence.
Main Results:
- Efficient and direct synthesis of aromatic alkene isocyanides.
- Demonstration of an unusual cycloaddition cascade for naphthalene synthesis.
Conclusions:
- The developed method provides a streamlined approach to synthesize challenging alkene isocyanides.
- This methodology enables access to substituted naphthalenes through a novel reaction pathway.
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