Ambident Reactivity of Medium-Ring Cycloalkane-1,3-dione Enolates1
journal contributionposted on 30.01.1998, 00:00 by Glenn S. Thompson, Jerry A. Hirsch
Cycloalkane-1,3-diones with ring sizes 7−10 have been converted to their enolates and subjected to a variety of ethylation and methylation reagent/solvent systems. The greatest amount of O-alkylation was encountered using ethyl tosylate in HMPA. The O/C alkylation ratios decreased with almost every reagent/solvent system as the ring size was increased. This trend is consistent with greater steric strain in the conjugated enolate resonance contributor, resulting in diminished O-attack as the ring size is increased.