PAIR-INDUCED CHEMICAL-SHIFTS (PAIRWISE CORRECTIONS) AND AN ADDITIVITY SCHEME FOR THE ESTIMATION OF AROMATIC H-1-NMR SHIFTS IN POLYSUBSTITUTED BENZENES WITH 2 OR MORE VICINAL SUBSTITUENTS

The aromatic H-1 NMR shifts of ortho-disubstituted benzenes were used to derive 285 pair-induced chemical shifts (pairwise corrections) for vicinal pairs of the substituent set (F, Cl, Br, I, NH2, NHCOMe, NO2, OH, OMe, Me, CHO, COMe, CN, Ph). Using these parameters and a simple additivity scheme, 617 ring H-1 shifts in polysubstituted benzenes with two or more vicinal substituents were reliably predicted with an average standard deviation of 0.08 ppm.