192372-28-4Relevant academic research and scientific papers
Synthesis, characterisation and reactions of 1,3-bis(trimethylsilyl)-1-aza-allyl-lanthanide complexes; X-ray structures of [Sm(LL′)2I(thf)], [Yb(LL′)2] and [RN=C(But) CH(R)]2 (thf = tetrahydrofuran, LL′ = η3-N(R)C(But) CHR, R=SiMe3)1
Hitchcock, Peter B.,Lappert, Michael F.,Tian, Shun
, p. 1 - 12 (1997)
Several lanthanide(II) and lanthanide(III) complexes of formula [Ln(LL′)2X(thf)n] (LL′ = η3-N(R)C(But)CHR, R = SiMe3; X = Cl, n = 1 and Ln = Ce 1 or Nd 2; or X = I, n = 1 and Ln = Sm 3; or X = I, n = 0 and Ln = Yb 4), [Sm(LL′)2(thf)] 5 and [Yb(LL′)2] 6 have been synthesised by the reaction of the appropriate lanthanide(II) or lanthanide(III) halide with two equivalents of 1,3-bis(trimethylsilyl)-1-aza-allyl-potassium [K(LL′)]n. Oxidation of 6 with Ag(OTf) afforded [Yb(LL′)2(OTf)] 7 (Tf = SO2CF3). The reaction of 6 with half an equivalent of I2 yielded as the main oxidative product 4 but also led to ligand coupling, forming [RN=C(But)CH(R)]2 8, which was also prepared by the reaction of [K(LL′)]n with I2. Treatment of 6 with two equivalents of PhCN yielded the previously known β-diketiminate [Yb(L′L″)2] [L′L″ = N(R)C(Ph)C(H)C(But)NR]. Complexes 1-8 were identified by C, H and N elemental analysis, multinuclear (1H, 13C, 29Si{1H}, 17Yb or 19F) NMR and mass spectra, of which 3, 6 and 8 were additionally characterised by single crystal X-ray diffraction.
Synthesis, characterisation and alkylation reactions of lanthanide β-diketiminates; crystal structures of and
Hitchcock, Peter B.,Lappert, Michael F.,Tian, Shuh
, p. 1945 - 1952 (2007/10/03)
Treatment of two equivalents of the sodium β-diketiminate Na(L-L) 1 with a lanthanide metal(III) chloride, LnCl3, yielded the mononuclear complex (Ln = Ce 3, Pr, Nd 5, Sm or Yb); similarly two equivalents of 1 with TmI3 gave (L-L = N(R)C(Ph)C(H)C(Ph)NR; R = SiMe3>.When 3 was mixed with either one or two equivalents of Li(CHR2) in diethyl ether, the only new cerium-containing product was 9.Lanthanide metal(III) β-diketiminates (Ln = Sm or Yb) or and 13 were obtained from (Ln = Sm or Yb) and K(L-L) in thf, or YbI2 and K(L-L) or K(L-L') in Et2O t)NR; thf = tetrahydrofuran>.The various lanthanide metal β-diketiminates were characterised by elemental analysis, mass spectrometry and multinuclear NMR spectra.The last of these indicated (by variable-temperature experiments) that for 13 two isomers were present.X-Ray diffraction data for 5 and 9 revealed that for each of these crystalline mononuclear complexes the metal atom is well shielded, due to the extremely sterically demanding monoanionic - ligand, which has some η5 character in these molecules.
