ANALYSIS OF ORGANIC-REACTIONS ON THE FRAMEWORK OF A 3-DIMENSIONAL REACTION DIAGRAM .1. CUBIC DIAGRAM AND ITS APPLICATION TO NUCLEOPHILIC-SUBSTITUTION REACTIONS

A three dimensional reaction diagram is proposed for the analysis of n ucloeophilic substitution reactions. In contrast to the More O'Ferrall approach this diagram includes not only the movement of the transitio n state along the reaction coordinate, but also along the two perpendi cular coordinates. One coordinate considers the variations on the dist ance between nucleophile, leaving group, and electrophilic center. The other perpendicular coordinate reflects the extent of single electron shift from one of these fragments to another. A theoretical treatment of the energy variation in the cubic diagram is developed. The main p arameters which have an influence on reactivity in nucleophilic substi tutions are analyzed. Comparison of the application of a cubic diagram for the analysis of reactivity with some known approaches is given.