POLYOL METAL-COMPLEXES .2. COPPER(II) COMPLEXES WITH MULTIPLY DEPROTONATED ETHYLENE-GLYCOL, ANHYDRO-ERYTHRITOL, OR METHYL ALPHA-D-MANNOPYRANOSIDE AS LIGANDS

Violet to blue crystals of the polyolate cuprates Li2[Cu(eth2-)2].6 H2O (1), A2[Cu(eryAn2-)2].4 H2O, A = Na (2a), K (2b), and Li3[Cu(Me-alpha-manpH2[2,3]2-)(Me-alpha-manpH[2,3,4]3-)].5 H2O (3) with anionic ligands derived from ethylene glycol (ethH2), anhydro-erythritol (eryAnH2), or methyl alpha-D-mannopyranoside (Me-alpha-manpH4), resp., are formed by the reaction of alkali metal hydroxide with cupric hydroxide and the proper polyol in aqueous solution. X-ray crystal structure determinations were carried out on all new compounds. In 1 - 3 deprotonated polyols form chelate complexes with copper ions; additionally, the polyolate ligands bind to alkali metal ions and/or they act as acceptors in asymmetric hydrogen bonds. In 3 one of the two O-2,O-3-mannosidato ligands is present as a trianion: O-4 is deprotonated, too, but instead of copper, the O-4-alkoxide group binds two lithium ions. The new compounds are discussed with respect to copper complexes of cellulose in alkaline media.