Transition metal complexes of substituted 2,2′-biquinolines. Part 1. The crystal and molecular structures of [8,8′-bis(aminomethyl)-2,2′-biquinoline]dichloromanganese(II) and [8,8′-bis(aminomethyl)-2,2′-biquinoline]chlorocopper(II) chloride

Abstract

The potentially quadridentate ligand, 8,8′-bis(aminomethyl)-2,2′-biquinoline (L¹) was prepared in 41% overall yield from 8,8′-dimethyl-2,2′-biquinoline by conversion to the 8,8′-bis(bromomethyl) derivative with N-bromosuccinimide, followed by reaction with NaN₃ and reduction with LiAlH₄. The complexes [Cu(L¹)Cl]Cl and [Mn(L¹)Cl₂] have been prepared and structurally characterised. The copper is in a distorted five-co-ordinate square-based pyramidal environment in [Cu(L¹)Cl]Cl with the co-ordinated chloride occupying the axial site; in contrast, the manganese complex exhibits a distorted octahedral geometry about the metal.