Crystal Structure of Di[oxydiacetatozinc(ii)]4,4'-Bipyridine

Abstract

Figure 1. ORTEP plot of the centrosymmetric title complex at the 50% probability level. Selected bond distances and angles: Znl-Ol = 2.060(2), Znl-03 = 2.064(2), Znl-05 = 2.122(2), Znl-Olw = 2.090(3), Znl-02w = 2.137(3), Znl-N1 = 2.063(3) Ä; Ol-Znl-03 = 152.3(1), Ol-Znl-05 = 76.1(1), Ol-Znl-Olw = 93.8(1), Ol-Znl-02w = 88.9(1), Ol-Znl-N1 = 103.5(1), 03-Znl-05 = 76.3(1), 03-Znl-Olw = 87.5(1), 03-Znl-02w = 87.8(1), 03-Znl-N1 = 104.2(1), 05-Znl-Olw = 87.4(1), 05-Znl-02w = 88.3(1), 05-Znl-N1 = 178.2(1), Olw-Znl-N1 = 90.9(1), Olw-Znl-02w = 174.3(1), 02w-Znl-N1 = 93.4(1)°. Symmetiy transformation: /= 1 -χ, 1 -y, 1 -z. CommentThe 4,4'-bipyridine spacer ligand has been used for the construction of an enormous .number of supramolecular one-, two-and three-dimensional metal-organic assemblies. Interest in the oligonuclear analogs is much less intense [1,2] despite the obvious advantage of a greater possibility for the formation of crystals by recrystallization that should result from these compounds with lower molecular weights. For the zinc(II) metal system in particular, the attempt to synthesize the 4,4'-bipyridine complex of zinc isophthalate afforded a photoluminescent layer-structured compound [3] whereas with zinc succinate, a chain compound is formed from the succinato entity, the 4,4'-bipyridine using only one of the nitrogen atoms to coordinate [4], Blocking three coordination sites by a tridendate dicarboxylato group should lead to the formation of a binuclear complex, and this has now been verified by the centrosymmetric title zinc oxydiacetate adduct. The octahedral geometry is completed by one half of the 4,4'-bipyridine ligand, and by two water molecules that are trans-to each other (Figure 1). The dinuclear units are connected by hydrogen bonds; the carboxyl oxygen atoms each forms only one hydrogen bond [2.730(3), 2.766(3) Ä] and the carbonyl oxygen atoms each form a pair of hydrogen bonds [2.791(4), 2.831(4) A; 2.811(4), 2.842(4) A] to fiirnish a network structure (Figure 2). In the mononuclear 2,2'-bipyrine adduct, the dianion also chelates to the zinc atom, which is also coordinated by a water molecule in an octahedral environment [5], ExperimentalThe title compound was obtained from a hydrothermal synthesis by reacting zinc nitrate, oxydiacetic acid, 4,4'-bipyridine and sodium hydroxide in a 1:1:1:2 molar ratio at 140 °C for 60 hours. CHN analysis: C 32.61, Η 4.20, Ν 4.32%. Calc. for C 18 H 2 8N 2 0 16 Zn 2 : C 32.80, Η 4.28, Ν 4.25%. 321Brought to you by | Purdue University Libraries Authenticated Download Date | 6/8/15 2:52 PM

Thiodiacetate and Oxydiacetate Cobalt Complexes: Synthesis, Structure and Stereochemical Features

“…Selected structural data are collected in Table 5. Complex 9 is isostructural with the zinc analogue [{Zn(oda)(H 2 O) 2 } 2 (μ‐4,4′‐bipy)] · 2H 2 O 23. Other cobalt complexes containing a tridentate dianionic ligand may be related to the present species 24…”