Anhydrous alkali metal lanthanide binaphtholates M 3 [Ln(binol) 3 ] (M ) Li, Na; Ln ) lanthanide or yttrium; H 2 binol ) binaphthol) are prepared by reaction of [Ln{N(SiMe 3 ) 2 } 3 ] with 3 equiv of MHbinol. Reaction of [Ln{N(SiMe 3 ) 2 } 3 ] (Ln ) Y or Yb) with 3 equiv of rac-LiHbinol gives a racemic mixture of RRS-and SSR-Li 3 [Ln(binol) 3 ] 2 as the only product. In contrast, reaction of [Ln{N(SiMe 3 ) 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 3-proton of the unique binol ligand in RRS-and SSR-Li 3 [Y(binol) 3 ] is shifted upfield by interaction with the π-system of a neighboring naphthyl ring. Analysis of paramagnetically induced 1 H 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(binol) 3 ]‚THF, 2a; rac-[Na(THF) 2 ] 3 [Y(binol) 3 ], 3; [Li(OEt 2 )] 3 -[Eu(S-binol) 3 ]‚[Li(OEt 2 )] 3 [Eu(S-binol) 3 (H 2 O)]‚2Et 2 O, 4; [Li(THF) 2 ] 2 [Li(OEt 2 )][Yb(S-binol) 3 ]‚ THF, 5; [Na(THF) 2 ] 3 [Yb(S-binol) 3 ], 6; [Na(THF) 2 ] 3 [La(S-binol) 3 (H 2 O)], 7.

Anhydrous lithium lanthanide binaphtholates have been prepared by reaction of lanthanide tris(silylamides) with 3 equiv of LiHbinol. Li3[Y(R-binol)3]·6THF has been characterized by single-crystal X-ray diffraction, and Li3[La(S-binol)3]·6THF has been shown to be an effective reagent for the enantioselective addition of MeLi to a range of aldehydes.

Complexes of lanthanide triflates Ln(OTf)3 with polyether (MeO(CH2CH2O) n Me) and poly(ethylene glycol) (HO(CH2CH2O) n H) ligands (n = 2−4) have been prepared and characterized, and the activity of these complexes as Lewis acid catalysts has been investigated. The complexes [Ln(OTf)3(HO(CH2CH2O) n H)] have been shown to catalyze the allylation of a range of aldehydes with allyltributylstannane, and the complexes [Ln(OTf)3(MeO(CH2CH2O) n Me)] catalyze the Diels−Alder addition of N-crotonyloxazolidinone to cyclopentadiene. The single-crystal X-ray structures of [Dy(OTf)2(H2O)2(MeO(CH2CH2O)4Me)][OTf] and [La(OTf)3(THF)(HO(CH2CH2O)4H)] are reported.

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