Calculation of the ring-current shifts of nuclear magnetic resonance signals caused by aromatic ligands in metal complexes

Abstract

Current-loop calculation has been carried out to estimate the n.m.r. ring-current shifts of protons of 1,10-phenanthroline (phen) ligands in [Co(phen)_m(en)_{3 –m}]³⁺(en = 1,2-ethanediamine; m= 1–3). Comparison of the calculated and observed shifts demonstrated that the calculation correctly predicts the upfield shift of an n.m.r. signal of a proton caused by aromatic ligands in a metal complex.