Chiral lanthanide shift reagents for

Chiral lanthanide shift reagents for soft Lewis bases have been prepared by mixing a chiral lanthanide tris-P-diketonate such as Ln (facam) 3 or Ln(hfbc)3 with a silver P-diketonate such as Ag(fod) (fod = 2,2-dimethyl-6,6,7,7,8,8,8-heptafluorooctane-3,5 dione). Addition of the two reagents leads to the formation of a binuclear reagent as illustrated in Equation [3]. The binuclear reagent consists of an ion pair between a lanthanide tetrakis chelate anion and a silver cation. 

Liu JH, Tsay JT. Use of chiral lanthanide shift reagents for the nuclear magnetic resonance spectrometric determination of amphetamine enantiomers. Analyst 1982 107 544—549. 

Ghosh I, Zeng H, Kishi Y. Appfication of chiral lanthanide shift reagents for assigmnent of absolute configuration of alcohols. Org. Lett. 2004 6 4715-4718. 

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