CHIRAL METAL-COMPLEXES .46. THE STRUCTURE OF 1(6,9)]OCTADECANE)PERCHLORATOCOPPER(II)PERCHLORATE

Thecrystalandmolecularstructure of 4R,12R-dimethyl)-1,5,9,13-tetraazat ricyclo[12,2,1, 1(6,9)]-octadecane}perchloratocopper(II) perchlorate, [Cu(S-mac5)ClO4]ClO4 has been determined by X-ray analysis. Crystal da ta: C16H32N4O8Cl8Cl2Cu is monoclinic, space group P2(1), a = 11.340(3) , b = 13.713(2), c = 15.002(1) Angstrom, beta = 97.13(1)degrees, Z = 4 . The structure was refined by full-matrix least-squares procedures to R = 0.056 for 3494 non-zero (I > 2 sigma(I) reflections and with eta = 1.03(11) confirming the configurations at the chiral centres. The tw o independent cations are structurally equivalent with the N-4 macrocy cle coordinating to the copper atom in a square-planar arrangement wit h Cu-N-sec of 1.988(6) and Cu-N-tert of 2.019(5) Angstrom, and a squar e-based pyramidal geometry is completed by an oxygen atom of a perchlo rate ion, Cu-O 2.63(1) Angstrom. Folding of the non-chelate five-membe red rings produces a conformation such that one face of the complex io n is more available for axial coordination of unidentate ligands.