CORRELATION OF ULTRAVIOLET SPECTRA WITH STRUCTURE VIA THE INTEGRATED MOLECULAR AND ELECTRONIC TRANSFORMS

摘要

The integrated molecular transform (FTm) has been used for the correlation of the structures of organic molecules with their physicochemical, thermodynamic, and pharmacological properties; it is also an excellent conformation index and functions as a discriminator of classical chemical structure types. In this study, it is used along with our recently introduced normalized molecular moment (M-n), and new structure indices, viz the integrated electronic transform (FTe), the integrated charge transform (FTc), and the electronic moment (M-e), to establish appropriate models for the title subject. Initially, the principal absorption maxima in each of several series were regressed against the structural indices to determine which index best represented the structures in the context of the absorption data. The indices were then selectively regressed against the absorption data to generate absorbance estimation equations. In a series of multicyclic hydrocarbons, the FTm functioned as a topological structure discriminator as well as a structure surrogate. In the topological subsets, the FTe and FTc also were selectively useful. For a series of conjugated dienes, the FTm, and the M-n were statistically appropriate. In a series of substituted benzenes, the discrimination of halobenzenes was apparent and could be represented by either the FTm, FTe, or M-e indices. For other variously substituted benzenes, the FTm is the extant model and further work with larger, structurally delineated series is warranted. For a series of monoalkyl-substituted nitrobenzenes, the FTm and FTe parameters are appropriate variables. Satisfactory correlation of molar absorptivities was not possible in this study as it would require absorption curve integration in the range where the maxima occurs. (C) 1997 John Wiley & Sons, Inc. [References: 25]