Volatile tris-tertiary-alkoxides of yttrium and lanthanum. The x-ray crystal structure of [La3(OBut)9(ButOH)2]
1991; Elsevier BV; Volume: 10; Issue: 10 Linguagem: Inglês
10.1016/s0277-5387(00)81368-6
ISSN1873-3719
AutoresD. C. Bradley, Halina Chudzynska, Michael B. Hursthouse, Majid Motevalli,
Tópico(s)Coordination Chemistry and Organometallics
ResumoTertiary alkoxides of yttrium and lanthanum have been prepared by addition of excess tertiary alcohol to the metal tris-(bis-trimethylsilylamides), M{N(SiMe3)2}3 (M = Y, La), and characterized by elemental analyses, NMR, IR and mass spectroscopy. With t-butanol and t-amyl alcohol the alcoholates [Y3(OBut)9(ButOH)2] (1), [Y3(OAmt)9 (AmtOH)2] (2) and [La3(OBut)9(ButOH)2] (3) were isolated. With higher tertiary alcohols the tris-t-alkoxides [M(OR)3] were obtained [M = Y, R = CMe2Pri (4), CMeEtPri (5), CEt3 (6); M = La, R = CMe2Pri (7), CMeEtPri (8)] as dimers. The coordinated ButOH in 1 could be replaced by THF or pyridine but not by trimethylamine. The X-ray crystal structure of 3 showed that the La3 triangle is capped by two μ3-OBut groups with three μ2-OBut bridges as in [La3(μ3-OBut)2(μ-OBut)3(OBut)4(ButOH)2]. The variable temperature NMR data suggest that compounds 1 and 2 have the same structure in solution as compound 3.
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