Construction of Two- and Three-Dimensional\nCoordination Polymers from Cobalt Trimesate

Abstract

Two new cobalt 1,3,5-benzenetricarboxylate (trimesic acid, TMA) coordination polymers\nwere synthesized and structurally characterized: [Co₃(H₂O)₆(TMA^3-)(TMA^2-)(TMA^1-)]·2H₂O\n(<b>1</b><b>) </b>and K[Co₃(TMA^3-)(TMA^2-)₂]·5H₂O <b></b>(<b>2</b>). <b>1</b> crystallizes in the hexagonal system, space group\n<i>P</i>6₅22 (no. 179), with <i>a</i> = 16.7265(2), <i>c </i>= 20.5822(4) Å, <i>V</i> = 4986.9(2) ų, and <i>D</i>_c = 1.889 g\ncm^-3. <b>2</b> is monoclinic, space group <i>P</i>2/<i>c </i>(no. 13), with <i>a</i> = 9.6096(1), <i>b</i> = 12.5610(1), <i>c </i>=\n13.9736(2) Å, <i>β</i> = 109.239(1)°, <i>V</i> = 1592.50(3) ų, and<i> D</i>_c = 1.938 g cm^-3. <b>1</b> is two-dimensional\nand formed by a “dense” stacking of {Co₃(H₂O)₆(TMA^3-)(TMA^2-)(TMA^1-)} layers. In compound\n<b>2</b> the connection of sinusoidal chains of cobalt octahedra by two types of trimesate ions gives\na three-dimensional network with pentahydrated channels.