Syntheses, crystal structures and electrospray mass spectra of coordination polymers of an N,N′-bis(3-pyridylmethyl)-1,4-benzenebis(methylamine) ligand and silver(I) salts

Four new coordination frameworks {[Ag-2(L1)](NO3)(2).2H(2)O}(n) (1), {[Ag(L1)](CF3COO).2.5H(2)O), (2), {[Ag-2(L1)(2)][1,4-C6H4(COO)(2)].7H(2)O)(n) (3) and {[Ag(L1)]ClO4}(n) (4) were obtained by the reaction of N,N'-bis(3-pyridylmethyl)-1,4 -benzenebis(methylamine) (Ll) with the corresponding silver(l) salts. X-ray diffraction analyses reveal that complex 1 has an infinite 1D chain structure, in which L1 acts as a tetradentate ligand. Complexes 2, 3 and 4 have 21) network structures, and the L1 tigands in these complexes adopt two different coordination modes: one kind of ligand coordinates four silver(I) atoms using its four N atoms, and the other kind of ligand connects only two silver(I) atoms with the two N atoms of the benzenebis(methylamine) unit, while the pyridine units remain free of coordination. Complex {[Ag(L2)]ClO4)(n) (5) was synthesized by reaction of N,N'-bis(3-pyridylmethyl)1,4-benzenebis(methyleneamine) (L2) with silver(I) perchlorate. It has a novel ID chain structure, which is different from that of 4 due to the different flexibility of the ligands L1 and L2. All of these complexes form 2D or 3D structures stabilized by hydrogen bonding, C-H...pi and pi-pi interactions. The results revealed that the nature of the counteranions and the flexibility of the ligand have an impact on the structure of the supramolecular architectures. The complexes were also characterized by electrospray mass spectrometry. ((C) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004).