Nolte, M; Pantenburg, I; Meyer, G
[{Hg(CF3)(2)}(ThpH)(H2O)](H2O) (1), [{Hg-4(ThP)(4)}(ClO4)(4)(H2O)(8)](H2O)(4) (2), [{Hg(ThpH)(2)} (NO3)](NO3) (3) and {Hg(Thp)Cl}(H2O) (4) (ThpH = theophylline, C7H8N4O2) have been synthesized by slow evaporation of aqueous solutions of the mercuric salts Hg(CF3)(2), Hg(ClO4)(2), Hg(NO3)(2), or HgCl2 and theophylline. Their crystal structures were determined on the basis of single crystal X-ray data. The coordination polymers 1 and 2 crystallize with triclinic symmetry, P (1) over bar (no. 2), with a = 468.8(2), b = 1256.4(5), c = 1445.5(6) pm, alpha = 67.15(3), beta = 89.21(3), gamma = 89.40(3)degrees and a = 833.6(1), b = 1862.7(2), c = 2182.9(2) pm, alpha = 111.61(1), beta = 90.98(1), gamma = 95.51(1)degrees, respectively. 3 and 4 crystallize with monoclinic symmetry, Pc (no. 7), a = 1194.1 (1), b = 1258.8(2), c = 735.5(2) pm, beta = 96.96(2)degrees and P2(1)/n (no. 14), a = 1069.0(2), b = 911.6(1), c = 1089.9(2) pm and beta = 96.87(2)degrees. In 1 the theophylline molecules are non-coordinating to mercury and leave the Hg(CF3)2 molecule unchanged. Only weak electrostatic attractions to one keto-oxygen atom of theophylline and one water molecule hold this co-crystallisate together. In 2, the theophyllinate anion, Thp(-), strongly coordinates with both N(7) and N(9) to Hg-II forming a large ring with eight Hg atoms that incorporates the water molecules. One sort of nitrate ions in 3 is weakly attached to Hg-II with the theophylline molecules still bound strongly through N(9). The chloride ligand and the theophyllinate ion seem to have the same strengths as ligands in 4 as they are both attached to Hg-II with the shortest distances possible.