Synthesis and X‐ray Crystal Structure of Bis[oxamide dioximato‐κ 2 N , N′ ](oxamide dioxime‐κ 2 N , N′ )cobalt(III) Perchlorate Hexahydrate

Co(OAc) 2 reacts with oxamide dioxime (H 2 oxado) in water in the presence of ClO 4 – ions to produce [Co(Hoxado) 2 (H 2 oxado)]ClO 4 · 6H 2 O ( 1 ), where Hoxado – is the anion of H 2 oxado, derived from the deprotonation of one of the two hydroximinic groups, and in which oxidation of Co II to Co III (in air) had occurred. 1 is the first example of a salt in which the cation, [Co(H 2 oxado) 3 ] 3+ , is doubly deprotonated to generate the chiral cation, [Co(Hoxado) 2 (H 2 oxado)] + . The central cobalt cation is pseudo‐octahedrally coordinated by six nitrogen atoms. In the solid state, the complex cations form centro‐symmetric dimers via O–H ··· O bridges. The bulk structure is consolidated by an extended three‐dimensional network of O–H ··· O and N–H ··· O bridges that interconnect the ionic constituents and the water molecules.