A redetermination of bis(ethylenediamine-N,N')bis(perchlorato-O)copper(II)

Reaction of copper(II) perchlorate with excess ethylenediamine (en) in aqueous solution gave the title complex, [Cu(ClO 4 ) 2 (C 2 H 8 N 2 ) 2 ]. The cation is centrosymmetric with a mean Cu-N distance of 2.016 (2) A. There are semi-coordinate bonds to the perchlorate ions with a Cu-O distance of 2.579 (4) A. The N-Cu-N angle is 84.69 (9)°, as expected for chelating en. The structure is stabilized by hydrogen bonds from three of the perchlorate O atoms to amino H atoms within each molecule and between molecules, linking them into chains.