A Nuclear Magnetic Resonance Study of the Binding of Trimethylphosphine Selenide to Cadmium Oleate

We report an NMR study on the binding of trimethylphosphine selenide (SePMe₃) to cadmium oleate (Cd­(OA)₂) in CDCl₃ and toluene-<i>d</i>₈. At room temperature in CDCl₃, SePMe₃ binds to Cd­(OA) ₂ in 1:1 ratio with a binding constant of 20 ± 3 as determined by NMR titration. The Cd-bound and free SePMe₃ are in fast exchange on the NMR time scale at room temperature and gives only one ³¹P NMR peak. At ca. 190 K, three ³¹P NMR peaks were observed for a toluene-<i>d</i>₈ solution of 1:1 mixture of Cd­(OA)₂ and SePMe₃. These three peaks were tentatively assigned to free SePMe₃ (9.0 ppm), 1:1 (19.5 ppm), and 2:1 complex between SePMe₃ and Cd­(OA)₂ (18.8 ppm)