Coordination polymeric structures in the sodium salt of 4-chloro-3-nitrobenzoic acid and the sodium and potassium salts of 4-nitroanthranilic acid

Wermuth

2014

Acta Crystallogr C

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The structures of two hydrated salts of 4-aminophenylarsonic acid (p-arsanilic acid), namely ammonium 4-aminophenylarsonate monohydrate, NH4(+)·C6H7AsNO3(-)·H2O, (I), and the one-dimensional coordination polymer catena-poly[[(4-aminophenylarsonato-κO)diaquasodium]-μ-aqua], [Na(C6H7AsNO3)(H2O)3]n, (II), have been determined. In the structure of the ammonium salt, (I), the ammonium cations, arsonate anions and water molecules interact through inter-species N-H...O and arsonate and water O-H...O hydrogen bonds, giving the common two-dimensional layers lying parallel to (010). These layers are extended into three dimensions through bridging hydrogen-bonding interactions involving the para-amine group acting both as a donor and an acceptor. In the structure of the sodium salt, (II), the Na(+) cation is coordinated by five O-atom donors, one from a single monodentate arsonate ligand, two from monodentate water molecules and two from bridging water molecules, giving a very distorted square-pyramidal coordination environment. The water bridges generate one-dimensional chains extending along c and extensive interchain O-H...O and N-H...O hydrogen-bonding interactions link these chains, giving an overall three-dimensional structure. The two structures reported here are the first reported examples of salts of p-arsanilic acid.

Section: Figurementioning

confidence: 74%

The three-dimensional hydrogen-bonded structures in the ammonium and sodium salt hydrates of 4-aminophenylarsonic acid

Wermuth

2014

Acta Crystallogr C

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“…The type of structure extension through the para-related nitro and carboxylate substituent groups of the PNBA À ligand found in (I), (II) and (III) is similar to those found in the alkali metal salts of 4-nitroanthranilic acid, viz. the sodium (a dihydrate) and potassium (a monohydrate) (Smith, 2013b), rubidium (a monohydrate; Smith, 2014b) and caesium (a monohydrate; Smith & Wermuth, 2011) salts. Within the six known examples of group 1 metal salts with PNBA, the nitrogroup participation in structure extension occurs in four examples, namely (I)-(III) and the K adduct salt (Shrivastava & Speakman, 1961).…”

Section: Figurementioning

confidence: 99%

The structures of the isomorphous potassium and rubidium salts of 4-nitrobenzoic acid and an overview of the metal complex stereochemistries of the alkali metal salt series with this ligand

2015

Acta Crystallogr C

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4-Nitrobenzoic acid (PNBA) has proved to be a useful ligand for the preparation of metal complexes but the known structures of the alkali metal salts of PNBA do not include the rubidium salt. The structures of the isomorphous potassium and rubidium polymeric coordination complexes with PNBA, namely poly[μ2-aqua-aqua-μ3-(4-nitrobenzoato)-potassium], [K(C7H4N2O2)(H2O)2]n, (I), and poly[μ3-aqua-aqua-μ5-(4-nitrobenzoato)-rubidium], [Rb(C7H4N2O2)(H2O)2]n, (II), have been determined. In (I), the very distorted KO6 coordination sphere about the K(+) centres in the repeat unit comprise two bridging nitro O-atom donors, a single bridging carboxylate O-atom donor and two water molecules, one of which is bridging. In Rb complex (II), the same basic MO6 coordination is found in the repeat unit, but it is expanded to RbO9 through a slight increase in the accepted Rb-O bond-length range and includes an additional Rb-O(carboxylate) bond, completing a bidentate O,O'-chelate interaction, and additional bridging Rb-O(nitro) and Rb-O(water) bonds. The comparative K-O and Rb-O bond-length ranges are 2.7352 (14)-3.0051 (14) and 2.884 (2)-3.182 (2) Å, respectively. The structure of (II) is also isomorphous, as well as isostructural, with the known structure of the nine-coordinate caesium 4-nitrobenzoate analogue, (III), in which the Cs-O bond-length range is 3.047 (4)-3.338 (4) Å. In all three complexes, common basic polymeric extensions are found, including two different centrosymmetric bridging interactions through both water and nitro groups, as well as extensions along c through the para-related carboxylate group, giving a two-dimensional structure in (I). In (II) and (III), three-dimensional structures are generated through additional bridges involving the nitro and water O atoms. In all three structures, the two water molecules are involved in similar intra-polymer O-H...O hydrogen-bonding interactions to both carboxylate and water O-atom acceptors. A comparison of the varied coordination behaviour of the full set of Li-Cs salts with 4-nitrobenzoic acid is also made.

“…For the structures of caesium 4-nitroanthranilate and caesium 3,5dinitrosalicylate, see: Smith & Wermuth (2011) and Meng (2011), respectively. For the structures of the sodium and potassium 4-nitroanthranilates, see: Smith (2013).…”

Section: Related Literaturementioning

confidence: 99%

Poly[bis(μ-2-amino-4-nitrobenzoato)di-μ-aqua-dirubidium]

2014

Acta Cryst E

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Key indicators: single-crystal X-ray study; T = 200 K; mean (C-C) = 0.006 Å; R factor = 0.046; wR factor = 0.075; data-to-parameter ratio = 12.3.In the structure of the title salt, [Rb 2 (C 7 H 5 N 2 O 4 ) 2 (H 2 O) 2 ] n , the asymmetric unit comprises two independent and different seven-coordinate Rb + cations, one forming an RbO 7 polyhedron, the other a RbO 6 N polyhedron, each of which is considerably distorted. The RbO 7 polyhedron comprises bridging O-atom donors from two water molecules, three carboxylate groups, and two nitro groups. The RbO 6 N polyhedron comprises the two bridging water molecules, one monodentate amine N-atom donor, one carboxyl O-atom donor and three O-atom donors from nitro groups (one from the chelate bridge). The extension of the dinuclear unit gives a three-dimensional polymeric structure which is stabilized by both intra-and intermolecular amine N-HÁ Á ÁO and water O-HÁ Á ÁO hydrogen bonds to carboxyl and water O-atom acceptors, as well as a number of inter-ring -interactions [minimum centroid-centroid separation = 3.364 (2) Å ]. The title salt is isostructural with the analogous caesium salt.