A Molecular Orbital Study on the Solvolysis of Aspirin Derivatives and Acyl-α-chymotrypsin

抄録

It was shown by Garrett (1957) that the addition of ethanol to water increased the rate of the solvolysis of aspirin. The solvolysis of aspirin derivatives has been studied by many researchers. However, the mechanism was not able to be explained. In this report, the mechanism of the solvolysis of aspirin derivatives were studied from the quantum chemical point of view by using the Complete Neglect of Differential Overlap/2 method. First, the hydrolysis of phenyl acetates as classical general base catalysis were explained theoretically. Secondly, the solvolysis of aspirin derivatives as concerted general base catalysis were explained theoretically. Thirdly, the solvolysis by using the groups concerned with the solvolysis of aspirin were explained theoretically. The reasonable structures of the solvolysis of aspirin derivatives were obtained, and the mechanism of the solvolysis was explained in terms of the presence of water in the monomer state for the transition state. In addition, as the approach to the mechanism of the hydrolysis of acyl-α-chymotrypsin, the explanations similar to those of the solvolysis of aspirin derivatives were applied.