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The ferrocenic ammonium (Rp)- and (Sp)-[1-CH2NR(3-)-2-CH3-C5H3Fe-C5H5] iodide salts with R=CH3, C2H5, n-C3H7, n-C4H9, were synthesized starting from the (Rp)- and (Sp)-[1-CH2N(CH3)2-2-CH3-C5H3Fe-C5H5] amines obtained in their optically active forms through asymmetric cyclopalladation of [C5H5Fe-C5H4CH2N(CH3)2]. 1H NMR studies of these planar chiral 1,2-disubstituted ferrocenic ammonium iodide salts in the presence of the (Delta)-(tris(tetrachlorobenzenediolato)phosphate(V) anion), [(Delta)-Trisphat] support the formation of specific diastereomeric ion pairs. Such intermolecular interactions can be related to the self-assembly of the two-dimensional optically active compounds [[(Sp)-1-CH2N(n-C3H7)3-2-CH3-C5H3Fe-C5H5][Mn (Delta)-Cr(C2O4)3]] and [[(Rp)-1-CH2N(n-C3H7)3-2-CH3-C5H3Fe-C5H5][Mn (Lambda)-Cr(C2O4)3]] starting from the resolved (Rp)- and (Sp)-[1-CH2N(n-C3H7)3-2-CH3-C5H3Fe-C5H5]+ ion associated to the racemic anionic building block rac-[Cr(C2O4)3]3- and Mn2+. Both enantiomeric forms of the networks behave as ferromagnets with a Curie temperature of 5.7 K.

/k(R)-1 are 1.7 and 1.6, respectively. Based on the known X-ray structural data for the active site of GO, it has been tentatively suggested that the enantioselectivity originates from the hydrophobic contact between the enzyme tyr-68 residue and the h 5 -C 5 H 5 ring of 1 , and a hydrogen bond network formed by his-516 and/or his-559 residues and the carboxylic group of the ferrocene derivative. The findings reported confirm the existence of enantioselective electron transfer between oxidoreductases and organometallic compounds with a planar chirality. The lack of kinetic enantioselectivity may be a result of i) the incorrect ratelimiting step, ii) unfavorable pH region, and iii) the deficit of charged groups attached to ferrocenes.

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