The syntheses and C, O, Si and P NMR spectra of a series of Mo(CO) ((PPh O) Y(R)R′) (Y(R) = P(O), Si(Me); R′=alkyl, haloalkyl, aryl) and [Mo(CO) (PPh O) ] Si complexes are given. The chemical shift ranges of the cis and trans carbonyl C and O, phenyl C(1) C and P resonances are relatively large and, with the exception of the cis carbonyl O chemical shifts, the correlations between the chemical shifts of the various resonances are excellent. These correlations are consistent with the model of metal carbonyl C and O chemical shifts proposed by Bodner and Todd. In addition they allow the model to be extended to include the diphenylphosphinite P chemical shifts in these complexes. The excellent correlations may be due to the presence of the chelate ring which limits the rotation around the molybdenum-phosphorus bond and to the fact that all three groups directly bonded to the phosphorus remains constant. © 1985. 13 17 29 31 13 17 13 31 17 13 17 31 4 2 2 4 2 2 2
