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O-Heterocycles from Unsaturated Carbonyls and Dimethoxycarbene
Jean-Philippe Croisetière1, Claude Spino1
1Département de Chimie , Université de Sherbrooke , 2500 Boulevard Université , Sherbrooke , Quebec J1K 2R1 , Canada.
The Journal of Organic Chemistry
|April 24, 2018
Summary
A novel (4+1)-annulation reaction creates cyclic orthoesters from dimethoxycarbene and unsaturated carbonyls. These intermediates are versatile precursors for synthesizing various O-heterocycles like furans.
Area of Science:
- Organic Chemistry
- Heterocyclic Chemistry
Background:
- O-heterocycles are important structural motifs in medicinal chemistry and materials science.
- Efficient synthetic routes to diverse O-heterocycles are highly sought after.
Purpose of the Study:
- To develop a new synthetic methodology for accessing O-heterocycles.
- To explore the utility of cyclic orthoesters as versatile intermediates.
Main Methods:
- The study employs a (4+1)-annulation reaction between dimethoxycarbene and α,β-unsaturated carbonyl compounds.
- Subsequent chemical transformations are used to convert the resulting cyclic orthoesters into other O-heterocycles.
Main Results:
- The (4+1)-annulation reaction successfully yields cyclic orthoesters.
- These orthoesters can be efficiently converted into methoxyfurans, furanones, and furans in a few steps.
Conclusions:
- A new and efficient route to O-heterocycles has been established.
- Cyclic orthoesters serve as valuable building blocks for diverse heterocyclic structures.
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