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The preparation of copper ascorbate in CH 2 Cl 2 is described. The reaction between copper(II) methoxide and L-ascorbic acid in the presence of N,N,N H ,N H -tetramethylethylenediamine (TMEDA) and under strictly anaerobic conditions leads to the formation of a stable Cu(II)-ascorbate complex. No redox reaction takes place. Spectroscopic evidence suggest that the compound is polymeric where Cu(II) is chelated by the enolic oxygens of one ascorbate unit and the side chain alcoholic oxygens of another.

The structure of the title compound, C6H18N22+.2Cl−, has been determined and has a centre of symmetry. The mol­ecule has strong intermolecular hydrogen bonding between each Cl− and an N—H bond [Cl⋯N = 3.012 (3) Å].

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The oxidative and non-oxidative alkali-catalyzed reactions of Lascorbic acid have attracted great interest, since similar degradation products are formed as in its metabolism. 1,2 The effects of the metal ions on the degradation of Ldehydroascorbic acid and oxalate formation with Co(II) and Gd(II) ions as a decomposition product of L-ascorbic acid in aqueous metal solutions have been clarified. 3,4 The title compound was prepared from mixtures of L-ascorbic acid (0.14 g, 0.8 mmol), N,N,N′,N′-tetramethyl-1,2-diaminoethane (0.12 mL, 0.8 mmol) and copper(II) methoxide (0.1 g, 0.8 mmol) in absolute methanol (70 mL). After filtration, a blue solution was set aside for crystallization at ambient temperature for a few days. Suitable blue crystals were obtained by recrystallization from ethanol.The results of an X-ray structure determination are given in Tables 1 -4