13C and 19F NMR chemical shifts of the iron carbene complex (CO)4FeCF2 - A case study at DFT level

The structure and chemical shifts of the carbene complex (CO)4FeCF2 were investigated at DFT level. The CF2 ligand will occupy an equatorial position in a trigonal bipyramidal iron complex. The carbenic C atom is calculated to be much more deshielded with respect to the CO ligand at both BP86 and B3LYP level. Anisotropies of 13C chemical shifts of carbenic C can show us the certain direction where the attack of nucleophilic regents may take place. The 19F NMR chemical shift is predicted to be in the range of 160-180 ppm respect to the standard CCl3F scale by GIAO calculations.