Inclusion of 4,4'-Bipyridine (γbpy) in Its Copper(II) Aqua Perchlorato Complex. Crystal Structure of [Cu( γbpy )(H₂O)₂(ClO₄)₂]_n.( γbpy )_n

Abstract

An example of a 4,4'-bipyridine ( γbpy ) clathrate in its copper(II) complex has been established. The compound, [Cu( γbpy )(H₂O)₂(ClO₄)₂]_n.( γbpy )_n, crystallizes in the monoclinic space group C2/c with a 16.651(3), b 11.089(2), c 14.360(3) Ǻ, β 116.45(3)°, V 2373.9(8)Ǻ³. The crystal structure comprises γbpy -bridged linear polymeric [Cu( γbpy )(H₂O)₂(ClO₄)₂]_n chains, where the copper atom, located on a crystallographic twofold axis, is coordinated in an elongated octahedral environment by two nitrogen atoms of the bridging γbpy ligands (Cu-N 1.998(4)Ǻ) and two water molecules (Cu-O 1.968(3)Ǻ) at the equatorial positions, and two perchlorate oxygen atoms at the axial positions (Cu-O 2.414(4)Ǻ). The chains are interconnected by hydrogen bonds between the aqua ligands and the uncoordinated perchlorate oxygen atoms to form two-dimensional layers with cavities each enclosing a γbpy molecule. Hydrogen bonding between the aqua ligands and the nitrogen atoms of the solvate γbpy molecules further extends the structure into a three-dimensional network in the solid.