A Novel Method for Characterization of Three-Dimensional Reaction Fields Based on Electrostatic and Steric Interactions toward the Goal of Quantitative Analysis and Understanding of Organic Reactions

A novel characterization method named FRAU ( F ield-characterization for r eaction a nalysis and u nderstanding), which numerically characterizes field around molecules based on electrostatic and steric interactions with pseudoreactant, has been developed for giving numeric measures of factors controlling reactions. FRAU estimates three kinds of features (FRAU features), i.e., extent of reaction field, electrostatic features, and steric features. Power of the FRAU features as discriminators recognizing similarities and differences of characteristics of structures and roles of reagents in reactions have been examined by 39 reagents containing Mg or B atoms. Similarities in these features were analyzed with the help of a s elf- o rganizing m ap (SOM). Good correspondences were found between the features, structures, and the role of the reagents in reaction. The results show abilities of FRAU to give useful numeric characterization of reagents.