Imidazole-imidazole stacking in some inorganic complexes

Abstract Reaction of CuCl 2  · 2H 2 O with the 1:1 condensate (L) of 2-(2-aminoethyl)pyridine and 1-methyl-2-imidazolecarboxaldehyde in methanol yields monomeric CuLCl 2 .H 2 O ( 1 ). Recrystallisation of 1 from aqueous methanol medium containing excess of PF 6 − affords the 1D coordination polymer [CuLCl] n (PF 6 ) n ( 2 ). A chloride bridge results in the coordination polymer. A face-to-face interaction is observed between the imidazole rings in 2 . The interaction influences the structure and magnetic properties of 2 markedly. The complex 2 is ferromagnetic with a J value of 1.79 ± 0.01 cm −1 . The imidazole fragments in 2 are coordinated to the metal. In mononuclear [ HgL 2 ″ ] (ClO 4 ) 2 , where L′′ is the 1:2 condensate of ethylenediamine and 1-methyl-2-imidazolecarboxaldehyde, the imidazolyl moieties are not under the direct influence of the metal. Here the imidazole – imidazole interaction is angular and more distant.