Allylic Displacements and a Novel Ester-Ether Interchange in Fused Cyclobutanones

Article abstract of DOI:10.1021/jo00367a012

Chlorophenylcyclobutanone 11, prepared by chlorophenylketene addition to cyclohexene, reacts readily with simple and hindered carboxylic acids in a cine substitution to produce keto esters 14.The acyloxy and phenyl substituents in 14c are shown by X-ray diffraction to be cis oriented; nevertheless 14 reacts with NaOMe at 20 deg C by an unusual ester-ether interchange to produce 15 and the released carboxylate RCO2^-.These reactions apparently proceed via an oxyallyl cation intermediate.The behaviors of related cyclobutanones 4, 6, and 11 with methoxide are contrasted.