An Easy Entry into Schiff Base Molecules Bearing a Pendant Primary Alcohol Function for Hydrogen Bonding

Abstract

A series of mono-oxidized pyridine, bipyridine, terpyridine and pyridine/pyridazine frameworks were prepared using MnO 2 as oxidant. Corresponding Schiff bases were prepared with aromatic or aliphatic amines carrying various functions such as paraffin chains, terminal acrylates and a second nitrogen atom. Various flexible tethers have been used for the ditopic ligands synthesis. These ligands formed dinuclear helicates for the shorter chains. The dinuclear copper(I) complex prepared from the CH 2 -CH 2 bridge is aggregated in the solid state by a hydrogen bonded network of the residual primary alcohol groups. For the longer spacers the ditopic ligand wraps around a single copper(I) centre forming a mononuclear complex. A significant merit of this work is that it allows the preparation of ligands and complexes retaining the hydroxymethyl function, which are likely to help to stabilize multidimensional networks in the solid state.