CLAISEN REARRANGEMENT OF CHORISMIC ACID AND RELATED ANALOGS - AN AB-INITIO MOLECULAR-ORBITAL STUDY

The structure and energies of the reactant and transition state for the Claisen rearrangement of chorismic acid and related analogues have been determined using ab initio molecular orbital methods. The rate acceleration found for chorismic acid compared to that of allyl vinyl ether is attributed to both reactant destabilisation and transition state stabilisation. The electronic effects responsible for the observed rate retardation associated with the ring carboxy and hydroxy groups have been identified.