Halogenation and Solvent Induced Shielding and Deshielding Effects in ¹H NMR and ¹³C NMR of Adamantane Derivatives

Abstract

Our study intent to report the halogenation and solvent influence on the adamantane moieties through ¹H NMR and ¹³C NMR using both experimental and computational techniques. Halogenation and solvent influence of adamantane in the NMR are quantified on the basis of the chemical shifts. Halogenation effects on the chemical shifts are mainly due to the deshielding effect caused by the high electronegativity on the halogenation position and its resultant effects on the surrounding chemical environment. Induction effect as a result of halogenation gives rise to normal halogen dependence (NHD) in the chemical shifts for ¹³C NMR of adamantane halides. On the other hand, adamantane derivatives demonstrate remarkable variations in the NMR spectra for solvents due to the significant influence of the solvent environment possessed by the various solvent parameters. To study solvent influence, we used CDCl₃ and DMSO‐d₆ solvents. Both measured and computed NMR spectra show strong agreement with each other. Noticeable variations obtained in the Lewis structure, global parameters, and electrostatic potential for all adamantane moieties also provide the support to the strong role of solvents and halogenation effects.