Sphericity and Sphericity Indices. A Non-Mathematical Approach on the Mathematical Basis for Restructuring Stereochemistry

摘要

Topicity terms for stereochemical relationships (homotopic, enantiotopic, diastereotopic, etc.) and topicity terms for stereochemical attributes (chirotopic and achiotopic) have been combined to discuss the stereochemistry of tetrahedral molecules. Stereochemical discussions due to such combined usage have exhibited complicated features that would cause misunderstanding or confusion. On the other hand, Sphericity terms (homospheric, enantiospheric, and hemispheric), which are based on orbits of ligands (or other objects), have been clarified to provide us with a simpler terminology for such stereochemical discussions. Sphericity indices have been defined and applied to examining the existence of derivatives.