Conformational-dependent reaction mechanism: case of acid hydrolysis of N-benzoyl-9-azabicyclo[6.1.0]non-4-ene

Quantum chemical studies of the acid hydrolysis of cis-cis-N-benzoyl-9-azabicyclo[6.1.0]non-4-ene in gas phase and sulfuric acid solution have been carried out. Conformational analysis of reactant and intermediates were done at DFT level of calculations, using different basis sets. Transition states were identified and IRC calculations were done at the same level. In the first step of the reaction, the protonation occurs preferentially on the nitrogen atom. Three products are obtained. The type of mechanism, stepwise or concerted, depends on the stable conformers and the cleaved N–C bond. The main conclusion is that the products of the reaction depend on the nature of the stable conformer of the reactant.