Pinwheel-shaped heterobimetallic lanthanide alkali metal binaphtholates: Ionic size matters!

被引：72

作者：

Aspinall, HC ^{[1
]}

Bickley, JF ^{[1
]}

Dwyer, JLM ^{[1
]}

Greeves, N ^{[1
]}

Kelly, RV ^{[1
]}

Steiner, A ^{[1
]}

机构：

[1] Univ Liverpool, Dept Chem, Donnan & Robert Robinson Labs, Liverpool L69 7ZD, Merseyside, England

来源：

ORGANOMETALLICS | 2000年 / 19卷 / 25期

关键词：

D O I：

10.1021/om0006256

中图分类号：

O61 [无机化学];

学科分类号：

070301 ; 081704 ;

摘要：

Anhydrous alkali metal lanthanide binaphtholates Ms[Ln(binol)(3)] (M = Li, Na; Ln = lanthanide or yttrium; H(2)binol = binaphthol) are prepared by reaction of [Ln{N(SiMe3)(2)}(3)] with 3 equiv of MHbinol. Reaction of [Ln{N(SiMe3)(2)}(3)] (Ln = Y or Yb) with 3 equiv of rac-LiHbinol gives a racemic mixture of RRS- and SSR-Li-3[Ln(binol)(2)](2) as the only product. In contrast, reaction of [Ln{N(SiMe3)(2)}(3)] with 3 equiv of rac-NaHbinol gives a racemic mixture of RRR- and SSS-Na-3[Ln(binol)(3)] when Ln = Y. When Ln =Yb, a 3:1 mixture of RRR-/SSS- and RRS-/SSR-Na-3[Ln(binol)(3)] is formed. Complexes have been characterized in solution by NMR spectroscopy. The S-proton of the unique binol ligand in RRS- and SSR-Li-3[Y(binol)(3)] is shifted upfield by interaction with the pi -system of a neighboring naphthyl ring. Analysis of paramagnetically induced H-1 NMR shifts of Yb complexes shows them to be entirely dipolar in origin. X-ray crystal structures have been determined for the following compounds: rac-[Li(THF)(2)](3)[Y(binpl)(3)].THF, 2a; rac-[Na(THF)(2)](3)[Y(binol)(3)], 3; [Li(OEt2)](3-)[Eu(S-binol)(3)] .[Li(OEt2)](3)[Eu(S-binol)(3)(H2O)].2Et(2)O, 4; [Li(THF)(2)](2)[Li(OEt2)][Yb(S-binol)(3)]. THF, 5; [Na(THF)(2)](3)[Yb(S-binol)(3)], 6; [Na(THF)(2)](3)[La(S-binol)(3)(H2O)], 7.

引用

页码：5416 / 5423

页数：8

共 20 条

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ABRAHAM RJ, COMMUNICATION

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