1,1'-Carbonylbis(3-methylimidazolium) triflate: an efficient reagent for aminoacylations

• Published in: Journal of the American Chemical Society Vol. 111; no. 13; pp. 4856 - 4859
• Main Authors: Saha, Ashis K, Rapoport, Henry, Schultz, Peter
• Format: Journal Article
• Language: English
• Published: WASHINGTON American Chemical Society 01.06.1989; Amer Chemical Soc
• Subjects: Chemistry; Chemistry, Multidisciplinary; Exact sciences and technology; Organic chemistry; Physical Sciences; Science & Technology; Aminoacylation; Five membered ring; Aminoester; Aliphatic compound; Nitrogen heterocycle; Iminium compounds; Saturated compound; Dipeptides; Ureas; Primary alcohol
• ISSN: 0002-7863; 1520-5126
• DOI: 10.1021/ja00195a043

Amino acid carboxyl activation and subsequent coupling with nucleophiles frequently suffer from uncertain risks of racemization, complex reagent preparation, or troublesome side-product removal. All of these difficulties are eliminated with a new, simple reagent, 1,1''-carbonylbis(3-methylimidazolium) triflate (CBMIT), obtainable readily by bis-alkylation of carbonyldiimidazole with methyl triflate. Via a highly reactive acyl imidazolium intermediate, CBMIT couples amino acid components or amino acids and alcohols to give peptides and esters, easily isolated in high yield. The reaction medium remains free of any base, and no loss of optical activity is observed.