| Abstract: | The use of Orbital Correspondence Analysis in Maximum Symmetry (OCAMS) for determining the allowed course of a reaction is described in terms of the familiar “A, S” notation. Several well known thermal and photochemical reactions are used as examples: Polyene cyclization; the fragmentation and dimerization of cyclobutadiene; π4 + π2] cycloaddition; the isomerization of Dewar-benzene. The relation of OCAMS to the classical correlation procedures of Woodward and Hoffmann and of Longuet-Higgins and Abrahamson is brought out, as are the sources of the occasionally contradictory predictions of OCAMS and of the classical procedures. |
