Ortho-lithiation ligands from

Investigation of the production of planar chiral ferrocene derivatives of use in catalytic asymmetric chemistry has led to the lithiation of N,AI-dimethylferrocenylmethylamine in the presence of non-stoichiometric levels of the chiral diamine tmcda (20% wrt ferrocenyl ligand). Data suggest the ability of this ligand to promote catalytic stereoselective ortho lithiation through the facile ability of Et20 to replace the chiral auxiliary as the lithiate converts from tmcda-complexed monomer to Et20-complexed dimer with retention of stereochemistry. ... 

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