Cascade coupling/cyclization process to N-substituted 1,3-dihydrobenzimidazol-2-ones.

Area of Science:

• Organic Chemistry
• Synthetic Methodology
• Medicinal Chemistry

Background:

• 1,3-dihydrobenzimidazol-2-one scaffolds are prevalent in pharmaceuticals and organic materials.
• Efficient and versatile synthetic routes are crucial for accessing diverse analogs.

Purpose of the Study:

• To develop a novel and efficient method for the synthesis of N-substituted 1,3-dihydrobenzimidazol-2-ones.
• To explore the functional group tolerance of the developed synthetic methodology.

Main Methods:

• Utilized methyl o-haloarylcarbamates as starting materials.
• Employed a copper(I) iodide (CuI) and amino acid co-catalyzed coupling reaction with primary amines.
• Performed a subsequent intramolecular condensative cyclization to form the benzimidazolone core.

Main Results:

• Successfully assembled a range of N-substituted 1,3-dihydrobenzimidazol-2-ones.
• Demonstrated broad functional group tolerance, including vinyl, nitro, carboxylate, amide, ester, ketone, and silyl ether groups.
• The reaction conditions proved robust and compatible with diverse substituents.

Conclusions:

• The developed CuI/amino acid catalyzed protocol provides an effective route to N-substituted 1,3-dihydrobenzimidazol-2-ones.
• This method offers a valuable tool for synthesizing complex molecules containing the benzimidazolone core, with potential applications in drug discovery and materials science.