Double Bond Stabilizing Abilities of Formyl, Carbo-tert-butoxy, and Carbomethoxy Substituents

Article abstract of DOI:10.1021/jo00135a011

Equilibrium constants for reactions of the type trans-MeCH=CHCH2COX <-> trans-EtCH=CHCOX, where X is H, OMe, and O-t-Bu, have been determined in tert-butyl alcohol solution at various temperatures by using basic catalysts.These equilibrium constants for formation of the conjugated isomer, extrapolated to 25 deg C, are 24, 4.9, and 5.1 for the aldehyde, methyl ester, and tert-butyl ester, respectively.Possible explanations for the relative magnitudes of these equilibrium constants are discussed.