Intramolecular solvation effects in the SN2 reaction Cl−+Cl(CH2)nCN

The chemical reactions Cl−+Cl(CH2)nCN (n=2–5) have been studied with ab initio molecular dynamics. The effects of the cyano group on the energy profile of the reactions as the length of the alkilic chain increases have been discussed in terms of electrostatics of the systems. The thermal effects have been computed in the Blue Moon Ensemble showing a large influence on the energy barriers. It has been shown that six membered hydrogen-bonded pre-reactive complexes are stable even at room temperature. The results of the simulation allow for an explanation for the increased reactivity of these systems compared to the parent Cl−+Cl(CH2)nCH3 reactions.

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