Gold-Catalyzed Cascade Cyclization and 1,3-Difunctionalization To Access Polysubstituted Furans
1Jiangsu Key Laboratory of Advanced Catalytic Materials & Technology, School of Petrochemical Engineering, Changzhou University, Changzhou 213164, P. R. China.
Organic Letters
|January 12, 2021
Summary
This study introduces novel gold-catalyzed reactions for synthesizing complex molecules from alkynyl enones and N,O-acetals. Selective control over 1,3-difunctionalization pathways, including oxyaminomethylation and aminomethylamination, was achieved by optimizing gold catalysts and reaction conditions.
Area of Science:
- Organic Chemistry
- Catalysis
- Synthetic Methodology
Background:
- Cascade reactions offer efficient synthetic routes to complex molecular architectures.
- Gold catalysis has emerged as a powerful tool for activating alkynes and enabling diverse transformations.
- N,O-acetals serve as versatile nucleophilic partners in organic synthesis.
Purpose of the Study:
- To develop novel gold-catalyzed cascade reactions for the 1,3-difunctionalization of 2-(1-alkynyl)-2-alken-1-ones.
- To explore the selective synthesis of 1,3-oxyaminomethylation and 1,3-aminomethylamination products.
- To investigate tandem cyclization and 1,4-oxyaminomethylation reactions.
Main Methods:
- Utilizing various gold catalysts (e.g., Au(I), Au(III) complexes) to mediate cascade cyclization and difunctionalization.
- Systematic variation of reaction parameters, including solvents, temperature, and catalyst loading.
- Employing N,O-acetals as key nucleophilic reagents in the presence of activated alkynyl enones.
Main Results:
- Discovery of novel gold-catalyzed cascade cyclization and 1,3-difunctionalization of alkynyl enones with N,O-acetals.
- Selective formation of 1,3-oxyaminomethylation and 1,3-aminomethylamination products by tuning gold catalysts and conditions.
- Successful achievement of tandem cyclization and 1,4-oxyaminomethylation pathways.
Conclusions:
- Gold catalysis provides an effective platform for controlling distinct cascade reaction pathways.
- The developed methodology offers access to novel heterocyclic compounds with potential applications.
- This work expands the scope of gold-catalyzed cascade reactions and difunctionalization strategies.
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