Cryptates with macrotricyclic ligands. The structure of the sodium [3]-cryptate [(C 32H 64N 4O 10)Na 2]I 2

Abstract

The macrotricyclic ligand C 32H 64N 4O 10 forms with sodium iodide the 1:2 complex of the [3]-cryptate type, (Na 2⊂L)I 2 (L = C 32H 64N 4O 10). This compound crystallizes in space group P2 1/c with a = 8.726(4), b = 10.114(7), c = 24.422(11) Å, β = 103.89(4)°, Z = 2. The structure was determined from diffractometer data by the heavy atom method and refined by least-squares to R(F) = 0.057 for 1927 reflections. The structure consists of centrosymmetric cations (Na 2⊂L) 2+ and I − anions; the sodium ions are accommodated inside the tricyclic ligand, with each bonded to two nitrogen and five oxygen atoms of L. The NaN distances are 2.70(1) and 2.73(1) and the NaO range from 2.39(1) to 2.48(1) Å. The iodide ions no longer interact with the sodium ions: all the Na +⋯I − separations exceed 5 Å. The distance between the sodium ions inside L is 6.40 Å.