1H NMR study of the substituent transmission effects through SO2 and CO groups in p,p′-disubstituted derivatives of phenyl phenacyl sulphones (β-keto sulphones)

Abstract

The NMR proton chemical shifts of the CH₂ group in phenyl phenacyl sulphones (β-keto sulphones)p-X-C₆H₄SO₂CH₂COC₆H₄-Y-p, measured in (CD₃)₂ are used to study transmission of the substituent effect through SO₂ and CO groups. Contrary to the estimation of this effect from CH₂-acidities [ρ(SO₂) < ρ(CO)]⁴ the results were that ρ(SO₂) > ρ(CO), and it was shown that application of σ_p⁺ gives a significantly better correlation than that with σ_p. These findings have been interpreted on the basis of structural data.