NMR-Untersuchungen an Organoelement(IVb)-phosphinen, III 1 Phosphor-Wolfram-Kopplungskonstanten in Pentacarbonyl-trimethylelement(IVb)-phosphin-Wolfram-Komplexen / NMR-Studies on Organoelement(IV b)-phosphines, III 1 Phosphorus-Tungsten Coupling Constants in Pentacarbonyl-trimethylelement(IVb)-phosphine Tungsten Complexes

Nuclear spin-spin coupling constants 1 J( 31 P- 183 W) are reported of trimethyl element (IVb)-phosphine substituted pentacarbonyl-tungsten complexes of the type [(CH 3 ) 3 E] n PR 3-n W(CO)5 (E = C, Si, Ge, Sn; R = t C 4 H 9 , C 6 H 5 ; n = 0, 1, 2, 3). Variations in the size of coupling constants are shown to depend mainly on the different ligand electronegativities.