Synthesis and crystal structure of aqua(2.2.2-cryptand)(perchlorato-O)lead(II) diaqua(2.2.2-cryptand)lead(II) tris(perchlorate)

A mixed complex aqua(2.2.2-cryptand)(perchlorato-O)lead(II) diaqua(2.2.2-cryptand)lead(II) tris(perchlorate), [Pb(2.2.2-Crypt)(CIO₄)(H₂O)]⁺ [Pb(2.2.2-Crypt)(H₂O)₂]²⁺ (ClO ₄ ^? )₃, is synthesized and studied by X-ray diffraction analysis. The crystals are orthorhombic: space group Pbca, a = 19.118 Å, b = 15.360 Å, c = 39.020 Å, Z = 8. The structure is solved by a direct method and refined by the full-matrix least-squares method in the anisotropic approximation to R = 0.089 for 7712 reflections (CAD-4 automated diffractometer, λMoK _α radiation). In each of the two complex cations of the host-guest type in the structure, the Pb²⁺ cation is coordinated by all the eight heteroatoms (6O + 2N) of the cryptand ligand and by two O atoms of the water molecule and ClO ₄ ^? anion or by two O atoms of two water molecules. In the crystal, alternating complex cations and ClO ₄ ^? anions are linked into infinite chains (along the z axis) through interionic hydrogen bonds O-H···O-Cl.