The coupling of Fmoc-Val-OH to NH₂-Tyr(t-Bu)-Wang resin and its kinetics were studied under microwave irradiation and conventional heating. The effect of reaction temperature on reaction rate was determined and the macroscopic kinetic parameters were obtained. The reaction stage is 2.3 and the activation energy is 104.7 kJ/mol under 300 W microwave irradiation, while the reaction stage is 2.9 and the activation energy is 142.4 kJ/mol under normal heating. The microwave irradiation brought the coupling yield of 68% under conventional heating up to 95% and the time required was shorten to 1/14 of that in conventional method.

Key words: solid phase peptide synthesis, coupling reaction, action kinetics, microwave synthesis