A computational (DFT) study on aza-Claisen rearrangement: Effect of temperature, solvent and substitution on activation barrier

The effect of temperature, solvent and substitution on aza-Claisen rearrangement has been studied using DFT. A contour diagram of potential energy surface (PES) of transition state (TS) is represented to explain the variation of activation barrier of aza-Claisen rearrangements for different substitutions. A comparison of aza-Claisen rearrangement with aza-cope, oxy- and thio-Claisen rearrangement has also been presented. The possible causes have been explored for the drastic conditions required for aza-Claisen rearrangement.