Author(s)

Mamadou Guy-Richard Kone, Sopi Thomas Affi, Nahossé Ziao^*, Kafoumba Bamba, Edja Florentin Assanvo

Laboratoire de Thermodynamique et de Physico-Chimie du Milieu, UFR SFA, Université Nangui Abrogoua, Abidjan, République de CÔte-d’Ivoire.

In this work, we have focused our investigations on the protonation sites predilection in the benzimidazolyl- chalcones (BZC) derivatives. Particularly, we are interested in the study of geometrical and energetical parameters. BZC are well known for their particularly nematicidal activity. Ten (10) BZC derivatives coded BZC-1 to BZC-10, with various larvicidal concentrations, have been selected for this work. They all are different one from another by the phenyl ring which is substituted by electron modulators such as alkyl, hydroxyl, alkoxy, aminoalkyl, halogen and nitro or replaced by the furan. Quantum chemical methods, namely HF/6-311 + G(d,p) and MPW1PW91/6- 311 + G(d,p) theory levels have been used to determine the geometrical and energetical parameters by the protonation on each heteroatom of the BZC derivative. An accuracy results with relatively less time consuming has been obtained using Hartree-Fock (HF) and Density Functional Theory methods (DFT/MPW1PW91). The calculations results allow identifying the sp² nitrogen as the preferential site of protonation in BZC derivative compounds.

Benzimidazolyl-Chalcone, Quantum Chemistry, Protonation, Proton Affinity, Gas Phase Basicity

Kone, M. , Affi, S. , Ziao, N. , Bamba, K. and Assanvo, E. (2016) Protonation Sites in Benzimidazolyl-Chalcones Molecules: An ab Initio and DFT Investigation. Computational Chemistry, 4, 65-72. doi: 10.4236/cc.2016.43006.