Struktur und reaktivität von ytterbiumbenzamidinaten

Abstract

Abstract The ytterbium(II) benzamidinates [RC6H4C(NSiMe3)2]2Yb(THF)2 (1a: R  H, 1b: R  OMe) react with diaryl diselenides and ditellurides to give ytterbium(III) complexes of the type [RC6H4C(NSiMe3)2]2Yb(SeR′)(THF) (2: R  H, R′  Ph; 3: R  H, R′  Mes) and [RC6H4C-(NSiMe3)2]2Yb(TeR′)(THF) (4: R  OMe, R′  Mes), respectively. The molecular structure of [PhC(NSiMe3)2]2Yb(SeMes)(THF) (3) has been determined by X-ray crystallography (triclinic, space group P 1 , a 1064.9(3), b 1377.1(3), c 3690(3) pm, α 68.61(2), β 89.46(3), γ 72.82(1)°, Z = 4, 10531 observed reflexions, R = 0.045). Moreover the strongly temperature-dependent 1H NMR spectra of 2 and 3 are discussed and 171Yb NMR spectra of some ytterbium(II) chelate complexes are reported.