Variations around 1D coordination polymers built from the triarylamine scaffold and Hg(II) or Cd(II)

摘要

Two tripodal ligands 1 and 2, derived from triarylamine (tris[4-(pyridin-4-yephenyl]amine (1) and tris(4'(pyridin-4-yl) [1,1' biphenyl]-4-yeamine (2)), have been synthesized and used for the formation of new 1D coordination networks. The synthesis and complete characterization of new 2 is described. Both ligands, that present the same geometry but different metrics, have been combined with V shape metalloligands (MX2)-X-II (M = Hg and X = Cl or M = Cd and X = I). The solid-state structures of the four new 1D coordination polymers (1-HgCl2, 1-HgCl2 center dot CHCl3, 2-HgCl2 and 2-CdI2 ) have been studied using X-ray diffraction on single crystals. The packing of networks and solvent molecules, when present within crystals, is mainly governed by pi-pi interactions. Depending on the nature of the ligand and the metalloligand, two types of coordination modes are observed: (i) ligand 1 may behave as a V shape connector with one pyridyl group remaining uncoordinated, and tetracoordinated Hg(II) cation leading, in 1-HgCl2, to a helicoidal arrangement; and (ii) ligands 1 and 2, when assembled with HgCl2 and CdI2 lead to a ladder-like structure (1-HgCl2 CHCl3, 2-HgCl2 and 2-CdI2), resulting from the recognition of the T-shape ligand (1 or 2), whereas all the pyridyl groups are involved in the coordination with the pentacoordinated M(II) cation. The tuning of the geometrical parameters of the 1D ladderlike networks appears possible through the initial choice of ligands.