THE CRYSTAL-STRUCTURES OF THE CRYPTATES AG(C222)X, X=CLO4-, NO3-, CLO3-, BRO3-, IO4-, REO4-, BF4-, PF6-, ASF6-, AND NA(C222)X, X=CLO4-, IO4-, REO4-

Single crystal structure determinations of the complexes of 21,24-hexa oxa-1,10-diazabicyclo-[8.8.8]hexacosane, C18H36N2O6 (=C222), with AgCl O4 (1) [R32, a=8.589(2)Angstrom, c=27.553(11)Angstrom, T=92K] and NaIO 4 (2) [Peen, a=10.402(5)Angstrom, b=13.452(9)Angstrom, c=17.172(9)Angs trom, T=293K] were performed. The cell constants of the cryptates Ag(C 222)X (X=NO3-, C1O(3)(-), BrO3-, ClO4-, IO4-, ReO4-, BF4-, PF6-, AsF6- ) and of Na(C222)ClO4 were determined from powder diffraction data, an d are all isotypic to (1). Indexing of the powder spectrum of Na(C222) ReO4 resulted in an orthorhombic unit cell comparable to that of (2), but with a c-axis reduced by one half. In these compounds the metal ca tions lying at the centres of the ligand cavities are clearly separate d from the anions [>5.4 Angstrom]. In both the AgClO4 and NaIO4 comple xes the metal cations have coordination numbers of 8, but the coordina tion types are quite different: Whereas the Ag+ ion prefers N to O coo rdination [2xAg...N 2.372(3)Angstrom, 6xAg...O 2.834(3)Angstrom], at t he Na+ ion the situation is inverted [2xNa...N 2.710(5)Angstrom, 6xNa. ..O 2.403(4)Angstrom-2.529(4) Angstrom]. The metal-ligand distances an d the conformational changes of the C222 ligand are discussed taking a s a basis the data of all known crystal structures containing this lig and.