Focused microwave-assisted parallel synthesis of bis-benzimidazoles

ORGN 341

Mei-Jung Lin, Wei-Bin Yeh, and Chung-Ming Sun. Department of Chemistry, National Dong Hwa University, 1, Sec.2, Da-Hseuh Rd, Shou-Feng, Hualien 974, Taiwan
Combinatorial parallel synthesis of bis-benzimidazoles by focused (mono-modal) microwave irradiation is described. Polymer immobilized o-phenylenediamines as a versatile template was synthesized under microwave irradiation. The resulting PEG bound diamines was N-acylated with 4-fluoro-3-nitrobenzoic acid selectively in primary aromatic amino moiety. Nucleophilic aromatic substitution of obtained amide was performed with different amines then cyclized to benzimidazole in acidic condition. Successive reduction, cyclization with various aldehydes yielded 5-(benzimidazol-2-yl)benzimidazoles. The desired products were released from the polymer support to afford the tri-substituted bis-benzimidazoles in good yields and purity.
 

Physical Organic, Combinatorial, Materials, Molecular Recognition
8:00 PM-10:00 PM, Tuesday, March 30, 2004 Anaheim Convention Center -- Hall A, Poster

Sci-Mix
8:00 PM-10:00 PM, Monday, March 29, 2004 Anaheim Convention Center -- Hall A, Sci-Mix

Division of Organic Chemistry

The 227th ACS National Meeting, Anaheim, CA, March 28-April 1, 2004