Chiral hexanuclear ferric wheels

Abstract

The homochiral iron(III) wheels [Fe(6){(S)-pedea}(6)Cl(6)] and [Fe(6){(R)-pedea)}(6)Cl(6)] [(R)- and (S)-2; pedea = phenylethylaminodiethoxide] exhibit high optical activities and antiferromagnetic exchange. These homochiral products react with each other, producing the centrosymmetric, crystallographically characterized [Fe(6){(S)-pedea}(3){(R)-pedea}(3)Cl(6)] diastereomer [(RSRSRS)-2]. (1)H NMR and UV-vis studies indicate that exchange processes are slow in both homo- and heterochiral systems but that, upon combination, the reaction between (R)- and (S)-2 occurs quickly.