Quantitative structure-electrochemistry relationships of α, β-unsaturated ketones

The half-wave potential (E12) of 26 substituted α,β-unsaturated ketones in non-aqueous acetonitrile were used in Hammett type quantitative structure-activity relationship (QSAR) analysis. A linear relationship between E12 and the electronic substituent constant, σx and reaction constant grR was revealed for 17 substituted chalcones. Linear regression equations were calculated using only the sum of σx,para + σx,meta of all substituents. It was found that the production of the substituted 1,2-oxaphosphol-4-en in the redox reaction of the α,β-unsaturated ketones and trialkyl phosphite can be predicted from the E12 values of the α,β-unsaturated ketones measured in nonprotic solvent. The E12 values also give a linear correlation with the conversions of the starting ketones.