Activation of carboxylic acids as their active esters by means of tert-butyl 3-(3,4-dihydrobenzotriazine-4-on)yl carbonate

✍ Scribed by Yochai Basel; Alfred Hassner

• Book ID: 104250748
• Publisher: Elsevier Science
• Year: 2002
• Tongue: French
• Weight: 217 KB
• Volume: 43
• Category: Article
• ISSN: 0040-4039
• DOI: 10.1016/s0040-4039(02)00324-6

✦ Synopsis

Carboxylic acids were activated in the presence of DMAP with tert-butyl carbonates (BOC-OX) 1, which were prepared in situ by reaction of X-OH and di-tert-butyl dicarbonate (BOC 2 O). The most efficient active carbonate proved to be tert-butyl 3-(3,4-dihydrobenzotriazine-4-on)yl carbonate 1a, leading to efficient formation of benzotriazinonyl esters 3 and 6, which are intermediates in reactions with primary and secondary amines to afford amides or peptides in good yield. By-products in the formation of 3 or 6 are the environmentally safe tert-BuOH and CO 2 . The hindered amino acid AIB also forms a dipeptide in good yield.