Solid-State ~(139)La and ~(15)N NMR Spectroscopy of Lanthanum-Containing Metallocenes

摘要

Lanthanide-containing metallocenes date back to the early 1950s,when Wilkinson reported the synthesis of compounds of the form (C_5H_5)_3Ln (Ln = Sc,Y,La,Ce,etc.).Initial development in this area was slow,due to the instability of these species;however,more recently,this area has shown spectacular growth,largely due to the unique structural and physical properties of these complexes,along with their novel reactivity and potential applications in catalytic processes.X-ray crystallography has been the primary means of structural characterization for these systems.Solid-state NMR has been utilized less frequently since many of these metallocenes are paramagnetic;however,there are some reports of solid-state NMR of the metal nuclei in these systems (e.g.,~(171)Yb and ~(89)Y).