226945-24-0Relevant articles and documents
Amide-stabilized, diamagnetic chromium(II) nitrosyl complexes
Jandciu, Eric W.
, p. 1994 - 2004 (2008/10/08)
Treatment of Cr(NO)(NiPr2)3 with 2 equiv of PhCO2H affords Cr(NO)(NiPr2)(O2CPh)2 (1) in good yields. Reaction of CpNa-DME with 1 produces CpCr(NO)(NiPr2)(OC(O)Ph) (2), which subsequently yields a series of 18-valence-electron (18e) complexes, CpCr(NO)(NiPr2)(R) (R = η1-Cp (3), CH2SiMe3 (4), η1-CH2Ph (5), Ph (6), CPh=CH2 (7), C≡CCMe3 (8), C≡CPh (9)) when treated with additional CpNa-DME or 1 equiv of the appropriate R2Mg·x(dioxane) reagent. 2-9 are low-spin (S = 0) compounds, and their electronic stability is attributed to the strong, synergic π-bonding interactions present in the [Cr(NO)(NiPr2)]2+ core, as indicated both by the NMR and IR spectra of these complexes and by the solid-state molecular structures of 2-4. The strong-field nitrosyl and amide ligands also enforce a diamagnetic configuration on the 14e bis(hydrocarbyl) complexes Cr(NO)(NiPr2)R2 (R = CH2SiMe3 (10), CH2Ph (11), o-tolyl (12)), which are obtained in good yields by reaction of 1 with 2 equiv of the corresponding R2Mg·x(dioxane) reactants. The solid-state molecular structures of 10 and 11 have also been established by single-crystal X-ray crystallographic analyses. Variable-temperature NMR spectroscopy was employed to study the fluxional processes occurring in 1, 10, and 11.
