metal-organic compounds
Poly[aqua(μ3-2-hydroxy-5-nitrobenzoato-κ3O1:O1′:O2)rubidium]
aFaculty of Science and Technology, Queensland University of Technology, GPO Box 2434, Brisbane, Queensland 4001, Australia, and bSchool of Biomolecular and Physical Sciences, Griffith University, Nathan, Queensland 4111, Australia
*Correspondence e-mail: g.smith@qut.edu.au
In the structure of title compound, [Rb(C7H4NO5)(H2O)]n, the centrosymmetric cyclic dimeric repeating unit comprises two irregular RbO4 complex centres bridged by the carboxylate groups of the 5-nitrosalicylate ligands. The coordination about each Rb atom is completed by a monodentate water molecule and a phenolic O-atom donor which gives a bridging extension [Rb—O range = 3.116 (7)–3.135 (5) Å]. The polymeric structure is stabilized by intermolecular water O—H⋯Ocarboxylate hydrogen bonds and weak inter-ring π–π interactions [minimum ring centroid separation = 3.620 (4) Å]. An intramolecular O—H⋯O hydrogen bond between phenol and carboxylate groups is also present.
Related literature
For the structures of some Rb complexes with aromatic carboxylic acids, see: Dinnebier et al. (2002); Wiesbrock & Schmidbaur (2003); Smith et al. (2007). For the structure of 5-nitroasalicylic acid and some salts and metal complexes of this acid, see: Kumar et al. (2003); Smith et al. (2005); Morgant et al. (2006).
Experimental
Crystal data
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Refinement
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Data collection: CrysAlis PRO (Oxford Diffraction, 2010); cell CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SIR92 (Altomare et al., 1994); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008) within WinGX (Farrugia, 1999); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: PLATON.
Supporting information
https://doi.org/10.1107/S1600536811037561/nk2111sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536811037561/nk2111Isup2.hkl
The title compound was synthesized by heating together under reflux for 15 minutes, 1 mmol quantities of 5-nitrosalicylic acid and rubidium hydroxide in 50 ml of 1:9 ethanol–water. After concentration to ca 30 ml, partial room temperature evaporation of the solution gave pale yellow needle prisms from which a suitable specimen was cleaved for the X-ray analysis.
The water and hydroxyl H atoms were located in a difference-Fourier synthesis and their positional and isotropic displacement parameters were allowed to ride together with the ring hydrogen atoms which were included in calculated positions with C—H = 0.93 Å and with Uiso(H) = 1.2Ueq(C,O).
The structures of the alkali metal complexes with aromatic
are of interest, particularly with the heavier metals Rb and Cs, because of their expanded coordination spheres and their ability to form polymeric systems. Although the structures of a series of metalII complex adducts with 5-nitrosalicylic acid (5-NSA), of the type [M(5-NSA-)(H2O)5]. (5-NSA). H2O (M = Mg, Co, Ni, Zn) have been reported (Morgant et al., 2006), no alkali metal complexes with 5-NSA are known. We obtained crystals of the title compound [Rb2(C7H4NO2)2(H2O)2]n from the reaction of 5-NSA with rubidium hydroxide and the structure is reported here.In the structure of this complex, the cyclic centrosymmetric dimeric repeating unit (Fig. 1) comprises two irregular RbO4 complex centres bridged by the carboxylate groups of the 5-NSA ligands. The coordination about each Rb is completed by a monodentate water molecule and a phenolic O donor which gives a bridging extension [Rb—O range 3.116 (7)–3.135 (5) Å]. The nitro O atoms (O51, O52) also give a weak symmetric bidentate association with inversion–related Rb centres [Rb—O, 3.290 (7), 3.261 (8) Å], a little too long to be considered formal Rb—O bonds. The coordination about Rb in this structure is therefore simpler than is found in other polymeric rubidium carboxylate complexes, e.g. and in rubidium salicylate (RbO7) (Dinnebier et al., 2002) and rubidium anthranilate monohydrate (RbO8) (Wiesbrock & Schmidbaur, 2003) and rubidium sulfosalicylate 1.33 hydrate (RbO7) (Smith et al., 2007).
The two-dimensional polymeric structure of the title compound (Fig. 2) is stabilized by intermolecular water O—H···Ocarboxyl hydrogen bonds (Table 1) and weak inter-ring π–π interactions [minimum ring centroid separation, 3.620 (4) Å]. The 5-NSA anion has the short intramolecular phenolic O—H···Ocarboxyl hydrogen bond and the essentially planar conformation commonly found in this ligand (Kumar et al., 2003; Smith et al., 2005) [torsion angles: C2—C1—C11—O11, -177.1 (7)°; C4—C5—N5—O52, 172.0 (7)°].
For the structures of some Rb complexes with aromatic
see: Dinnebier et al. (2002); Wiesbrock & Schmidbaur (2003); Smith et al. (2007). For the structure of 5-nitroasalicylic acid and some salts and metal complexes of this acid, see: Kumar et al. (2003); Smith et al. (2005); Morgant et al. (2006).Data collection: CrysAlis PRO (Oxford Diffraction, 2010); cell
CrysAlis PRO (Oxford Diffraction, 2010); data reduction: CrysAlis PRO (Oxford Diffraction, 2010); program(s) used to solve structure: SIR92 (Altomare et al., 1994); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008) within WinGX (Farrugia, 1999); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: PLATON (Spek, 2009).[Rb(C7H4NO5)(H2O)] | F(000) = 560 |
Mr = 285.60 | Dx = 1.965 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ybc | Cell parameters from 4363 reflections |
a = 11.9738 (5) Å | θ = 3.4–28.8° |
b = 12.0230 (4) Å | µ = 5.14 mm−1 |
c = 6.9571 (3) Å | T = 200 K |
β = 105.401 (4)° | Needle, yellow |
V = 965.59 (7) Å3 | 0.50 × 0.20 × 0.10 mm |
Z = 4 |
Oxford Diffraction Gemini-S CCD-detector diffractometer | 1893 independent reflections |
Radiation source: Enhance (Mo) X-ray source | 1651 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.027 |
Detector resolution: 16.077 pixels mm-1 | θmax = 26.0°, θmin = 3.4° |
ω scans | h = −14→14 |
Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction, 2010) | k = −14→14 |
Tmin = 0.572, Tmax = 0.980 | l = −8→8 |
6051 measured reflections |
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.054 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.181 | H-atom parameters constrained |
S = 1.17 | w = 1/[σ2(Fo2) + (0.1295P)2 + 0.7347P] where P = (Fo2 + 2Fc2)/3 |
1893 reflections | (Δ/σ)max < 0.001 |
136 parameters | Δρmax = 0.81 e Å−3 |
0 restraints | Δρmin = −1.11 e Å−3 |
[Rb(C7H4NO5)(H2O)] | V = 965.59 (7) Å3 |
Mr = 285.60 | Z = 4 |
Monoclinic, P21/c | Mo Kα radiation |
a = 11.9738 (5) Å | µ = 5.14 mm−1 |
b = 12.0230 (4) Å | T = 200 K |
c = 6.9571 (3) Å | 0.50 × 0.20 × 0.10 mm |
β = 105.401 (4)° |
Oxford Diffraction Gemini-S CCD-detector diffractometer | 1893 independent reflections |
Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction, 2010) | 1651 reflections with I > 2σ(I) |
Tmin = 0.572, Tmax = 0.980 | Rint = 0.027 |
6051 measured reflections |
R[F2 > 2σ(F2)] = 0.054 | 0 restraints |
wR(F2) = 0.181 | H-atom parameters constrained |
S = 1.17 | Δρmax = 0.81 e Å−3 |
1893 reflections | Δρmin = −1.11 e Å−3 |
136 parameters |
Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell e.s.d.'s are taken into account in the estimation of distances, angles and torsion angles |
Refinement. Refinement of F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > σ(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger. |
x | y | z | Uiso*/Ueq | ||
Rb1 | 0.11224 (4) | −0.11709 (4) | 0.23072 (7) | 0.0208 (2) | |
O1W | 0.0713 (6) | −0.1033 (5) | −0.2300 (10) | 0.068 (2) | |
O2 | 0.1661 (5) | 0.3786 (4) | 0.5968 (10) | 0.056 (2) | |
O11 | 0.2015 (5) | 0.0401 (5) | 0.5983 (9) | 0.063 (2) | |
O12 | 0.0880 (4) | 0.1881 (5) | 0.5829 (8) | 0.0583 (19) | |
O51 | 0.6650 (5) | 0.2709 (6) | 0.5398 (9) | 0.070 (2) | |
O52 | 0.6074 (6) | 0.1054 (5) | 0.5877 (13) | 0.068 (3) | |
N5 | 0.5896 (5) | 0.2061 (6) | 0.5701 (9) | 0.049 (2) | |
C1 | 0.2840 (6) | 0.2186 (6) | 0.5897 (9) | 0.041 (2) | |
C2 | 0.2690 (6) | 0.3339 (6) | 0.5920 (10) | 0.043 (2) | |
C3 | 0.3609 (7) | 0.4063 (7) | 0.5906 (11) | 0.049 (3) | |
C4 | 0.4652 (7) | 0.3660 (6) | 0.5873 (12) | 0.046 (2) | |
C5 | 0.4801 (6) | 0.2488 (6) | 0.5818 (9) | 0.043 (2) | |
C6 | 0.3918 (6) | 0.1769 (6) | 0.5851 (10) | 0.042 (2) | |
C11 | 0.1863 (7) | 0.1422 (6) | 0.5922 (11) | 0.043 (2) | |
H2 | 0.10940 | 0.32000 | 0.58910 | 0.0670* | |
H3 | 0.34960 | 0.48270 | 0.59180 | 0.0580* | |
H4 | 0.52640 | 0.41390 | 0.58870 | 0.0560* | |
H6 | 0.40380 | 0.10050 | 0.58420 | 0.0500* | |
H11W | 0.11310 | −0.05780 | −0.28540 | 0.0810* | |
H12W | 0.02110 | −0.12980 | −0.34140 | 0.0810* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Rb1 | 0.0199 (4) | 0.0188 (4) | 0.0234 (4) | −0.0022 (2) | 0.0050 (2) | 0.0002 (2) |
O1W | 0.069 (4) | 0.071 (4) | 0.058 (4) | −0.022 (3) | 0.009 (3) | 0.002 (3) |
O2 | 0.045 (3) | 0.058 (4) | 0.065 (4) | 0.005 (2) | 0.014 (3) | −0.003 (2) |
O11 | 0.072 (4) | 0.048 (4) | 0.074 (4) | −0.007 (3) | 0.027 (3) | −0.008 (3) |
O12 | 0.045 (3) | 0.071 (4) | 0.059 (3) | −0.002 (3) | 0.014 (2) | −0.005 (3) |
O51 | 0.053 (3) | 0.071 (4) | 0.090 (4) | −0.007 (3) | 0.026 (3) | 0.003 (4) |
O52 | 0.057 (4) | 0.050 (4) | 0.099 (5) | 0.012 (3) | 0.024 (4) | 0.007 (3) |
N5 | 0.043 (3) | 0.047 (4) | 0.056 (4) | −0.002 (3) | 0.012 (3) | 0.004 (3) |
C1 | 0.045 (4) | 0.042 (4) | 0.035 (3) | 0.000 (3) | 0.010 (3) | −0.005 (3) |
C2 | 0.043 (4) | 0.046 (4) | 0.040 (4) | 0.005 (3) | 0.013 (3) | 0.003 (3) |
C3 | 0.058 (5) | 0.042 (4) | 0.047 (4) | 0.005 (3) | 0.015 (4) | 0.002 (3) |
C4 | 0.050 (4) | 0.044 (4) | 0.047 (4) | −0.009 (3) | 0.016 (3) | 0.002 (3) |
C5 | 0.044 (4) | 0.044 (4) | 0.039 (3) | 0.004 (3) | 0.009 (3) | 0.000 (3) |
C6 | 0.048 (4) | 0.039 (4) | 0.038 (3) | 0.000 (3) | 0.011 (3) | 0.002 (3) |
C11 | 0.046 (4) | 0.044 (4) | 0.039 (4) | −0.003 (3) | 0.010 (3) | −0.009 (3) |
Rb1—O1W | 3.116 (7) | N5—C5 | 1.430 (10) |
Rb1—O11 | 3.131 (6) | C1—C11 | 1.491 (11) |
Rb1—O12i | 3.132 (5) | C1—C2 | 1.399 (10) |
Rb1—O2ii | 3.135 (5) | C1—C6 | 1.393 (10) |
O2—C2 | 1.353 (10) | C2—C3 | 1.405 (11) |
O11—C11 | 1.240 (9) | C3—C4 | 1.345 (12) |
O12—C11 | 1.286 (10) | C4—C5 | 1.422 (10) |
O51—N5 | 1.252 (9) | C5—C6 | 1.371 (10) |
O52—N5 | 1.230 (9) | C3—H3 | 0.9300 |
O1W—H11W | 0.8900 | C4—H4 | 0.9300 |
O1W—H12W | 0.9000 | C6—H6 | 0.9300 |
O2—H2 | 0.9700 | ||
O1W—Rb1—O11 | 137.27 (16) | C6—C1—C11 | 120.9 (7) |
O1W—Rb1—O12i | 120.79 (17) | C1—C2—C3 | 120.7 (7) |
O1W—Rb1—O2ii | 68.54 (16) | O2—C2—C3 | 118.3 (7) |
O11—Rb1—O12i | 87.66 (15) | O2—C2—C1 | 121.0 (6) |
O2ii—Rb1—O11 | 68.78 (16) | C2—C3—C4 | 120.6 (7) |
O2ii—Rb1—O12i | 127.80 (16) | C3—C4—C5 | 118.8 (7) |
Rb1—O2ii—C2ii | 129.2 (4) | N5—C5—C6 | 119.8 (7) |
Rb1—O11—C11 | 123.7 (5) | C4—C5—C6 | 121.4 (7) |
Rb1i—O12—C11 | 130.8 (5) | N5—C5—C4 | 118.7 (7) |
Rb1—O1W—H11W | 121.00 | C1—C6—C5 | 119.8 (7) |
Rb1—O1W—H12W | 139.00 | O11—C11—C1 | 120.1 (7) |
H11W—O1W—H12W | 100.00 | O12—C11—C1 | 116.5 (6) |
Rb1iii—O2—H2 | 119.00 | O11—C11—O12 | 123.4 (8) |
C2—O2—H2 | 110.00 | C2—C3—H3 | 120.00 |
O51—N5—C5 | 119.9 (7) | C4—C3—H3 | 120.00 |
O52—N5—C5 | 119.0 (7) | C3—C4—H4 | 121.00 |
O51—N5—O52 | 121.1 (7) | C5—C4—H4 | 121.00 |
C2—C1—C6 | 118.7 (7) | C1—C6—H6 | 120.00 |
C2—C1—C11 | 120.5 (7) | C5—C6—H6 | 120.00 |
O1W—Rb1—O11—C11 | 32.4 (7) | C2—C1—C6—C5 | −0.4 (9) |
O12i—Rb1—O11—C11 | −102.9 (6) | C11—C1—C6—C5 | 179.7 (6) |
O2ii—Rb1—O11—C11 | 29.5 (6) | C2—C1—C11—O11 | −177.1 (7) |
O1W—Rb1—O12i—C11i | −62.5 (6) | C2—C1—C11—O12 | 4.5 (10) |
O11—Rb1—O12i—C11i | 83.8 (6) | C6—C1—C11—O11 | 2.9 (10) |
O1W—Rb1—O2ii—C2ii | −96.4 (6) | C6—C1—C11—O12 | −175.5 (6) |
O11—Rb1—O2ii—C2ii | 81.5 (6) | C11—C1—C2—O2 | 0.1 (10) |
Rb1—O2ii—C2ii—C1ii | −159.4 (5) | C11—C1—C2—C3 | 179.7 (6) |
Rb1—O2ii—C2ii—C3ii | 20.2 (9) | C6—C1—C2—O2 | −179.9 (6) |
Rb1—O11—C11—O12 | 73.6 (9) | C6—C1—C2—C3 | −0.3 (10) |
Rb1—O11—C11—C1 | −104.7 (7) | O2—C2—C3—C4 | 179.5 (7) |
Rb1i—O12—C11—O11 | 34.3 (11) | C1—C2—C3—C4 | −0.1 (11) |
Rb1i—O12—C11—C1 | −147.4 (5) | C2—C3—C4—C5 | 1.1 (11) |
O51—N5—C5—C4 | −8.9 (9) | C3—C4—C5—N5 | 177.5 (7) |
O52—N5—C5—C4 | 172.0 (7) | C3—C4—C5—C6 | −1.7 (11) |
O51—N5—C5—C6 | 170.3 (6) | N5—C5—C6—C1 | −177.8 (6) |
O52—N5—C5—C6 | −8.8 (10) | C4—C5—C6—C1 | 1.4 (10) |
Symmetry codes: (i) −x, −y, −z+1; (ii) x, −y+1/2, z−1/2; (iii) x, −y+1/2, z+1/2. |
D—H···A | D—H | H···A | D···A | D—H···A |
O2—H2···O12 | 0.97 | 1.61 | 2.468 (8) | 145 |
O1W—H11W···O11iv | 0.89 | 1.90 | 2.794 (9) | 179 |
O1W—H12W···O12v | 0.90 | 1.96 | 2.861 (9) | 180 |
Symmetry codes: (iv) x, y, z−1; (v) −x, −y, −z. |
Experimental details
Crystal data | |
Chemical formula | [Rb(C7H4NO5)(H2O)] |
Mr | 285.60 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 200 |
a, b, c (Å) | 11.9738 (5), 12.0230 (4), 6.9571 (3) |
β (°) | 105.401 (4) |
V (Å3) | 965.59 (7) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 5.14 |
Crystal size (mm) | 0.50 × 0.20 × 0.10 |
Data collection | |
Diffractometer | Oxford Diffraction Gemini-S CCD-detector |
Absorption correction | Multi-scan (CrysAlis PRO; Oxford Diffraction, 2010) |
Tmin, Tmax | 0.572, 0.980 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 6051, 1893, 1651 |
Rint | 0.027 |
(sin θ/λ)max (Å−1) | 0.617 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.054, 0.181, 1.17 |
No. of reflections | 1893 |
No. of parameters | 136 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.81, −1.11 |
Computer programs: CrysAlis PRO (Oxford Diffraction, 2010), SIR92 (Altomare et al., 1994), SHELXL97 (Sheldrick, 2008) within WinGX (Farrugia, 1999), PLATON (Spek, 2009).
D—H···A | D—H | H···A | D···A | D—H···A |
O2—H2···O12 | 0.97 | 1.61 | 2.468 (8) | 145 |
O1W—H11W···O11i | 0.89 | 1.90 | 2.794 (9) | 179 |
O1W—H12W···O12ii | 0.90 | 1.96 | 2.861 (9) | 180 |
Symmetry codes: (i) x, y, z−1; (ii) −x, −y, −z. |
Acknowledgements
The authors acknowledge financial support from the Australian Research Committee, the Faculty of Science and Technology and the University Library, Queensland University of Technology and Griffith University.
References
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The structures of the alkali metal complexes with aromatic carboxylic acids are of interest, particularly with the heavier metals Rb and Cs, because of their expanded coordination spheres and their ability to form polymeric systems. Although the structures of a series of metalII complex adducts with 5-nitrosalicylic acid (5-NSA), of the type [M(5-NSA-)(H2O)5]. (5-NSA). H2O (M = Mg, Co, Ni, Zn) have been reported (Morgant et al., 2006), no alkali metal complexes with 5-NSA are known. We obtained crystals of the title compound [Rb2(C7H4NO2)2(H2O)2]n from the reaction of 5-NSA with rubidium hydroxide and the structure is reported here.
In the structure of this complex, the cyclic centrosymmetric dimeric repeating unit (Fig. 1) comprises two irregular RbO4 complex centres bridged by the carboxylate groups of the 5-NSA ligands. The coordination about each Rb is completed by a monodentate water molecule and a phenolic O donor which gives a bridging extension [Rb—O range 3.116 (7)–3.135 (5) Å]. The nitro O atoms (O51, O52) also give a weak symmetric bidentate association with inversion–related Rb centres [Rb—O, 3.290 (7), 3.261 (8) Å], a little too long to be considered formal Rb—O bonds. The coordination about Rb in this structure is therefore simpler than is found in other polymeric rubidium carboxylate complexes, e.g. and in rubidium salicylate (RbO7) (Dinnebier et al., 2002) and rubidium anthranilate monohydrate (RbO8) (Wiesbrock & Schmidbaur, 2003) and rubidium sulfosalicylate 1.33 hydrate (RbO7) (Smith et al., 2007).
The two-dimensional polymeric structure of the title compound (Fig. 2) is stabilized by intermolecular water O—H···Ocarboxyl hydrogen bonds (Table 1) and weak inter-ring π–π interactions [minimum ring centroid separation, 3.620 (4) Å]. The 5-NSA anion has the short intramolecular phenolic O—H···Ocarboxyl hydrogen bond and the essentially planar conformation commonly found in this ligand (Kumar et al., 2003; Smith et al., 2005) [torsion angles: C2—C1—C11—O11, -177.1 (7)°; C4—C5—N5—O52, 172.0 (7)°].