title: Tungsten-183 NMR study of cis-[W(CO)4(PPh3)(4-RC5H4N)]; effect of varying the σ donor strength of the pyridine.
abstract: Tungsten-183 NMR data are reported for the complexes cis-[W(CO)4(PPh3)(4-RC5H4N)] (R = H, Me, Ph, COMe, COPh, OMe, NMe2, Cl, NO2). The (183)W chemical shift (obtained by indirect detection using (31)P) is found to correlate with the Hammett σ function for the group R, with (183)W shielding increasing approximately linearly with the donor strength of the pyridine over a range of 93 ppm. The X-ray structures of cis-[W(CO)4(PPh3)(4-MeOC5H4N)] and cis-[W(CO)4(PPh3)(4-PhCOC5H4N)] are also reported.
authors: Molecular Sciences Institute, School of Chemistry, University of the Witwatersrand, Johannesburg, South Africa. laurence.carlton@wits.ac.za
authors: Laurence
authors: L
authors: Carlton
authors: Lebohang V
authors: LV
authors: Mokoena
authors: Manuel A
authors: MA
authors: Fernandes
mesh_terms: D007554:Isotopes / Q000737:chemistry; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000737:chemistry*; D011725:Pyridines / Q000737:chemistry*; D014414:Tungsten / Q000737:chemistry*
chemical_list: D007554:Isotopes; D009942:Organometallic Compounds; D011725:Pyridines; C023666:pyridine; D014414:Tungsten