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Tertiary aminoferrocenes complexed to boron trifluoride (BF 3 ) are shown to undergo asymmetric lithiation with alkyllithiums in the presence of bulky chiral 1,2-diaminocyclohexane ligands. This reaction represents the first BF 3 -activated asymmetric lithiation of a prochiral aromatic amine and the first such transformation to be mediated by a chiral di-A C H T U N G T R E N N U N G amine other than (À)-sparteine. The process provides rapid access to a broad range of enantiomerically enriched 2-substituted-1-aminoferrocenes, including derivatives with uncommon substitution patterns that are of interest in catalysis. The enantioselectivity of the process is high enough (87:13 to 91:9 er) to allow for isolation of single enantiomers of several products after simple recrystallization as either the free aminoferrocenes or their ammonium fluoroborate salts. Both antipodes of the planar chiral 2-substituted-1-aminoferrocene products are accessible, as confirmed by single crystal X-ray diffraction analysis of two compounds with opposite relative stereochemistry. Single-point calculation of thirty-two different transition states of the reaction at the M06-2X/6-311 + gA C H T U N G T R E N N U N G (2d,2p) level produced a computational model that correctly predicted both the sense and extent of chiral induction. Three factors appeared to play important roles in determining enantioinduction during lithiation of BF 3 -complexed tertiary aminoferrocenes: (i) the maintenance of a highly organized eight-membered ring transition state; (ii) the existence of a strong Li···F contact which placed the chiral diamine ligand in close proximity to the ferrocene substrate; (iii) the orientation of the sterically demanding N-alkyl groups of the chiral diamine additives, either away or towards, the aminoferrocene and the alkyllithium. The model may serve as a predictive tool for the rational design of new ligands for this and related asymmetric lithiations.

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