Kinetics and mechanism of the aminolysis of thiophenyl methylacetates in acetonitrile

Abstract

and cross-interaction constant ρXZ is relatively large and positive (0.90). These trends are consistent with the rate-limiting breakdown of a tetrahedral intermediate, T ± . The proposed mechanism is also supported by adherence of the rate data to the reactivity-selectivity principle (RSP). The kinetic isotope effects, kH/kD, are greater than unity (1.3-1.4) suggesting a possibility of hydrogen-bonded four-centered transition state. The activation parameters, ΔH ≠ and ΔS ≠ , are consistent with this transition-state structure.