Abstract
Tris(trifluoromethyl)boron complexes have unusual properties and may find applications in many fields of chemistry, biology, and physics. To gain insight into their NMR properties, the isotropic ^11^B, ^13^C, and ^19^F NMR chemical shifts of a series of tris(trifluoromethyl)boron complexes were systematically studied using the gauge‐included atomic orbitals (GIAO) method at the levels of B3LYP/6‐31 + G(d,p)//B3LYP/6‐31G* and B3LYP/6‐311 + G(d,p)//B3LYP/6‐311 + G(d,p). Solvent effects were taken into account by polarizable continuum models (PCM). The calculated results were compared with the experimental values. The reason that the structurally inequivalent fluorine atoms in a specific species give a same chemical shift in experimental measurements is attributed to the fast rotation of CF~3~ group around the BC(F~3~) bond because of the low energy barrier. The calculated ^11^B, ^13^C(F~3~), and ^19^F chemical shifts are in good agreement with the experimental measurements, while the deviations of calculated ^13^C(X, X = O, N) chemical shifts are slightly large. For the latter, the average absolute deviations of the results from B3LYP/6‐311 + G(d,p)//B3LYP/6‐311 + G(d,p) are smaller than those from B3LYP/6‐31 + G(d,p)//B3LYP/6‐31G*, and the inclusion of PCM reduces the deviation values. The calculated ^19^F and ^11^B chemical shieldings of (CF~3~)~3~BCO are greatly dependent on the optimized structures, while the influence of structural parameters on the calculated ^13^C chemical shieldings is minor. Copyright © 2009 John Wiley & Sons, Ltd.