Nuclear magnetic resonance study of the association between adamantanone and the shift reagent Eu(fod)3

Abstract

The association of Eu(fod)₃(L) to adamantanone (S) in CDCl₃ was studied by ¹H n.m.r. spectroscopy. From the concentration dependence of the induced shifts the bound shifts were obtained by an optimization procedure and a gradient method. The equilibrium constants for the formation of complexes LS, LS₂, and LS₃ were calculated. The best fit was found for the two-step association LS,LS₂ with association constants K₁₁ 63 dm³ mol^–1 and K₁₂ 514 dm³ mol^–1. The position of europium in the complex adduct was studied by one- and four-site binding models and both results were statistically compared.