A fluorous-tagged linker from which small molecules are released by ring-closing metathesis

Area of Science:

• Organic Chemistry
• Synthetic Chemistry
• Catalysis

Background:

• Nitrogen heterocycles are crucial scaffolds in medicinal chemistry and materials science.
• Efficient and scalable synthesis of diverse nitrogen heterocycles remains a challenge.
• Ring-closing metathesis (RCM) is a powerful tool for forming cyclic structures.

Purpose of the Study:

• To develop a fluorous-tagged linker system for parallel synthesis of nitrogen heterocycles.
• To achieve simultaneous "cyclization-release" of products and catalyst liberation.
• To demonstrate the versatility of the method for small-, medium-ring, and macrocyclic compounds.

Main Methods:

• Design and synthesis of a fluorous-tagged sulfonamide linker.
• Functionalization of the linker using Fukuyama-Mitsunobu reactions with unsaturated alcohols.
• Purification of functionalized linkers via fluorous-solid-phase extraction (F-SPE).
• Ring-closing metathesis using a fluorous-tagged Grubbs-Hoveyda catalyst.
• Purification of cyclic products by F-SPE to remove linker and catalyst.

Main Results:

• Successful synthesis of a fluorous-tagged linker and its functionalization.
• Demonstration of "cyclization-release" of nitrogen heterocycles coupled with catalyst liberation.
• Efficient purification of diverse cyclic products using F-SPE.
• Preparation of a wide range of small-, medium-ring, and macrocyclic nitrogen heterocycles.
• Validation of the linker design using a non-fluorous model.

Conclusions:

• The fluorous-tagged linker system provides an efficient and streamlined approach for synthesizing nitrogen heterocycles.
• The "cyclization-release" strategy simplifies purification and enables parallel synthesis.
• This method is broadly applicable for constructing diverse cyclic nitrogen-containing compounds.