SYNTHESIS AND CRYSTAL-STRUCTURE OF THE 1/1 PD(II) COMPLEX OF 1,4,7,10-TETRAOXA-13,16,19,22-TETRAAZACYCLOTETRACOSANE

The synthesis and structural characterization of [1.Pd](PF6)2, complex 3, where 1 = 1,4,7,10-tetraoxa-13,16,19,22-tetraazacyclotetracosane, are reported. The palladium atom in the complex is coordinated by the four ligand nitrogen atoms in an essentially square planar structure (average Pd-N bond length=2.040(1) angstrom). A further weak apical interaction exists (2.98 angstrom) to one O atom of the ligand. The pale yellow crystals of Pd(C16H36N4O4) (PF6)2 are monoclinic with unit-cell dimensions a = 15.222(7), b = 20.480(9), c = 8.733(4) angstrom, beta = 91.53(4)-degrees, V = 2722(2) angstrom3, space group P2(1)/c (No. 14) and Z = 4. Crystals of [1.Pd](PF6)2 are, thus, isomorphous with those of a Cu(PF6)2 salt of 1, complex 2, reported earlier (J. L. Sessler, J. W. Sibert, J. D. Hugdahl and V. Lynch, Inorg. Chem., 28 (1989) 1417-1419). The coordination around Cu, however, is better described as square pyramidal with a long Cu-O axial contact (2.47(2)).