Substituent-induced chemical shifts in 3- and 4-substituted styrenes: definition of substituent constants and determination of mechanisms of transmission of substituent effects by iterative multiple linear regression

摘要: Iterative multiple linear regression analysis of substituent-induced chemical shifts in 3- and 4-substituted styrene derivatives is used to redefine σF substituent constants (with respective standard errors ca. 0.01 0.005). Correlations with the data for various model systems indicate that these are applicable sets involving both shift acidity measurements aprotic media. The approach we have a homogeneous set large number variables particularly suited providing well-defined dual parameter more common neutral substituents.Correlations individual nuclei entirely consistent previously proposed effects field, resonance, polarization effects. From results other systems, it concluded respectively pure field resonance constants. It pointed out combination detaile...