Metal-organophosphonate chemistry: Hydrothermal syntheses and structures of copper(II)-xylyldiphosphonates with organonitrogen coligands

The hydrothermal reactions of copper(II) acetate monohydrate or copper(II) chloride dihydrate with xylyl-phosphonic acid derivatives in the presence of organonitrogen coligands yielded a series of compounds of the Cu(II)/ligand/xylyl-diphosphonate system. The materials structurally characterized in the study include the parent compound [Cu-2(H2O)(2)(1,4-O3PC8H8PO3)] (1); the o-phenanthroline derivatives: [Cu(H2O)(o-Phen)(1,4-HO3PC8PO3H)]center dot 3H(2)O (2 center dot 3H(2)O), [Cu-2(H2O)(2)(1,4-O3PC8H8PO3)]center dot 3H(2)O (3 center dot 3H(2)O), [Cu(o-phen)(1,4-HO3PC8H8PO3H)]center dot 3H(2)O (4 center dot 3H(2)O), [Cu(o-phen)(1,2-HO3PC8H8PO3H)] (5), and [Cu (o-phen)(1,3-HO3PC8H8PO3H)] (6); the 2,2'-bipyridine derivatives: [Cu-2(H2O)(2)(bpy)(2)(1,4-HO3PC8H8PO3 H-2)(2)(HO3PC8H8PO3H)]center dot H2O (7 center dot H2O); [Cu(bpy)(1,4-HO3PC8H8PO3H)]center dot 2H(2)O (8 center dot 2H(2)O), and [Cu(bpy)(1,3-HO3PC8H8PO3H)] (9); the tetra-2-pyridylpyrazine materials: [Cu-2(H2O)(2)(tpypyz)(1,4-HO3PC8H8PO3H)(2)center dot(1,4-H2O3PC8H8PO3H2)(2)center dot 2H(2)O (10 center dot(H62O3PC8H8PO3H2)(2)center dot 2H(2)O), [Cu-2(tpypyz)(1,2-HO3PC8H8PO3H)(2)]center dot 2H(2)O (11 center dot 2H(2)O), and [Cu4Cl4(tpypyz)(2)(1,4-H2O3PC8H8PO3H)(2)]Cl-2 center dot H2O3PC8H8O3H2 center dot 8H(2)O (12 center dot H2O3PC8H8O3 H-2 center dot 8H(2)O); and the di-2,2'-pyridylamine compound [Cu(2,2dpy)(HO3PC8H8PO3H)] (13). The role of the coligand in modifying the overall dimensionality of the ultimate products is apparent. Rather than observing the common pillared layer frameworks characteristic of metal-diphosphonate materials, the o-phenthroline derivatives, compounds 4 and 5 are two-dimensional, 3 and 6 are one-dimensional and 2 is molecular. For the 2,2'-bipyridyl analogues, 8 is two-dimensional while 9 is one-dimensional and 7 is molecular. Similarly, the tetra-2-pyridylpyrazine derivatives provide a one-dimensional material 10 and two molecular species 11 and 12. (C) 2013 Elsevier B. V. All rights reserved.