Indium(III)-catalyzed hydrative cyclization of 1,7-diynyl ethers

Area of Science:

• Organic Chemistry
• Synthetic Chemistry
• Catalysis

Background:

• Diynyl ethers are versatile precursors in organic synthesis.
• Cyclization reactions are crucial for constructing heterocyclic compounds.
• Tetrahydrofuran derivatives have applications in pharmaceuticals and materials science.

Purpose of the Study:

• To report a new hydrative cyclization of 1,7- and 1,8-diynyl ethers.
• To synthesize 2,2-disubstituted tetrahydrofurans with exocyclic enone appendages.
• To explore the reaction's scope, mechanism, and potential applications.

Main Methods:

• Utilized catalytic indium(III) iodide (InI(3)) and p-toluenesulfonic acid (p-TSA) as a co-catalyst.
• Investigated reaction conditions for optimization.
• Performed mechanistic studies and subsequent transformations.

Main Results:

• Successfully prepared several 2,2-disubstituted tetrahydrofurans with exocyclic enone appendages.
• Demonstrated the efficiency and scope of the hydrative cyclization.
• Showcased the transformation of the products into a C-nucleoside analog.

Conclusions:

• The reported hydrative cyclization is an effective method for synthesizing complex tetrahydrofuran derivatives.
• The reaction provides a valuable synthetic pathway for accessing molecules with potential biological activity.
• Further transformations highlight the utility of this methodology in medicinal chemistry.