Synthesis and characterisation of an octaazamacrobicyclic ligand using alkali-metal ions as templates; characterisation of a dicopper complex as the perchlorate salt

Abstract

A polyazamacrobicyclic compound (cryptand) has been synthesised in good yield from tris(2-aminoethyl)amine and glyoxal as a [2 + 3] condensation product in the presence of rubidium or caesium ion as a template. On reduction by NaBH₄ this gives a potentially multidentate ligand N(CH₂CH₂-NHCH₂CH₂NHCH₂CH₂)₃N (L) for transition-metal ions. A dicopper complex [Cu₂L(ClO₄)][ClO₄]₃ has been isolated in the solid state as the perchlorate salt and characterised by elemental analysis, electrochemistry, room-temperature magnetic susceptibility, IR, electronic and EPR spectroscopy.