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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.

A complex of samarium diiodide (SmI(2)) with tetraglyme catalyzes the intermolecular pinacol coupling of aromatic or aliphatic aldehydes at loadings of 10 mol % in the presence of Me(2)SiCl(2) and Mg. Diastereoselectivity of up to 95/5 (+/-/meso) has been achieved for aliphatic aldehydes and up to 19/81 (+/-/meso) for aromatic aldehydes. De values of up to 99% have been achieved in intramolecular pinacol coupling reactions using the SmI(2)/tetraglyme/Mg/Me(2)SiCl(2) catalytic system.

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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 chlorides with pybox ligands catalyze the enantioselective silylcyanation of aromatic and aliphatic aldehydes with ee's of up to 91% under mild and convenient conditions. Studies of catalysts prepared with pybox ligands of varying enantiomeric purity show no marked nonlinear effects, indicating a monometallic transition state. A mechanism for the catalytic reaction is proposed. Crystal structures of [LnCl2(S-Pri-pybox)2][LnCl4(S-Pri-pybox)] (Ln = Eu, Yb) are reported. The structure of the related triflate complex [La(OTf)3(S-Pri-pybox)2] is also reported. Diastereoselectivity has been observed in the reactions of Ln(OTf)3 with racemic Pri-pybox:  for Ln = Eu, a heterochiral product containing one R- and one S-pybox ligand is observed, whereas for Ln = Yb a racemic mixture of homochiral bis(pybox) complexes is formed.

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