New approaches to degenerate interconversions of organic structures : 1. Levels of structural degeneracy and computer-aided search for degenerate rearrangements

The general methodology of systematic search for degenerate interconversions must be based on a certain hierarchy of degeneracy.The levels and sublevels of the proposed hierarchy are represented by topological and structural types and subtypes of degeneracy, which correspond to specific equations and to graphs identifying them.Graph operations that enable an efficient search for arbitrary types of organic reactions are formulated, and problems specific to generation of degenerate transformations are considered.In conclusion, results of computer-aided search (using the ARGENT-1 software) for new heteroderivatives and structural analogs of the Cope reaction are discussed.Many of the rearrangements thus found (especially [3,3]-shifts in cations and anions, which have not been studied to date) can be subjects of experimental investigations.