The Effect of Microwave Irradiation Towards Carbodiimide-Mediated Esterifications on Solid Phase
Alexander Stadler and Oliver Kappe,
Karl-Franzens UniversityDate Posted: Tuesday, September 19, 2006
One of the most common solid-phase reactions in combinatorial synthesis involves the coupling of an acid (i.e. an amino acid) to polystyrene solid supports (i.e. Wang or Merrifield resin). A number of publications have reported the coupling of carboxylic acids to Merrifield resin via the cesium salt method and the esterification of Wang resin using carbodiimide either via the isourea method or the symmetrical anhydride method. Since the reaction times using conventional conditions have been reported to be rather long (16-48 h) we have investigated the effects of microwave irradiation towards both of these reactions using benzoic acid derivatives.
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