Summary Endocyclic alkylation of ketone enolates is shown to depend critically upon the size of the so formed ring and six- but not five-membered cyclic ketones can be synthesized in this way; a rationale for this difference is presented. ... KETONIC substances of the general type (1) can be de- protonated to the isomeric enolates (2) or (3) which, in principle, may be intramolecularly alkylated (when Y is a leaving group) to the ring structures (4) or (5). Since these ...
