A formalism for the classification and design of organic reactions III. The class of (+ ‐ )nC reactions

This paper deals with reactions involving an odd number of atoms. The bonds between the atoms alternatingly increase or decrease by one unit but one of the bonds remains unaffected. The reaction operator in terms of the formalism employed in the two previous papers thus is (+ ‐)nC in which C indicates the Constancy of the last mentioned bond. Many synthetically important processes belong to this class, among others acid‐ or base‐induced eliminations, ditto additions, isomerisations and substitutions, dipolar cycloadditions, fragmentations and tele‐reactions.