THE STATISTICAL GENERATION OF SCS VALUES AND INTERACTION FACTORS FOR THE C-13 NMR-SPECTRA OF ARENES

A new methodology which statistically determines substituent chemical shifts (SCS) and interaction factors of adjacent groups for use in the C-13 NMR spectroscopy of arenes is described. From a data base of 15, 255 signals we have computed several hundred of these ''statistical'' SCS values (SSCS values), and interaction factors for many common pair s of groups. Some interaction factors for 1,2,3-substitution are also reported. When these SSCS values and interaction factors are used to p redict the signal position they are found to give a correlation coeffi cient of predicted verses observed values of 0.994 with a standard dev iation of 1.5 ppm.