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Acta Cryst. (2007). E63, m2573    [ doi:10.1107/S1600536807044728 ]

cyclo-Tetra-[mu]-oxido-tetrakis[3-nitro-4-hydroxyphenylarsenic(III)]

N. C. Lloyd and B. K. Nicholson

Abstract top

The title compound, [As4O4(C6H4NO3)4], has an eight-membered As4O4 ring with a slightly twisted boat-chair conformation. The aryl groups complete the threefold coordination for each As atom. Each OH group forms a strong intramolecular O-H...O hydrogen bond to the adjacent NO2 group, with only weak C-H...O, O...As [3.036 (6)-3.184 (6) Å] and O...O [2.921 (10)-2.930 (10) Å] interactions between tetramers.

Comment top

Aryl arsenoxides of empirical formula RAsO exist as either hydrates RAs(OH)2 as for the 4-H2NC6H4 example (Knock et al., 1995), or as cyclic (RAsO)n where n = 4 for R = Me (DiMaio & Rheingold, 1991), Ph (Muller & Muhle, 1999), mesityl (Arif et al., 1987), or 3-F3CC6H4 (Sun et al., 2005) and n = 5 for R = Et (Hausler & Sheldrick, 1997). The title compound, [3-O2N-4-HOC6H3AsO]4, also forms an eight-membered As4O4 ring which has a slightly twisted boat-chair conformation. The aryl groups complete the 3-coordination for each As atom. Average parameters are: As—O = 1.801 (6) Å, O—As—O = 98.8 (3)° and As—O—As = 121.3 (4)°. The OH group is internally H-bonded to the adjacent NO2 group, so the intermolecular interactions between tetramers are weak C—H···O and O····As ones. There are also some short intermolecular O···O interactions involving the NO2 groups.

Related literature top

A related compound, (4-H2NC6H4)As(OH)2, was reported by Knock or Knoch et al. (1995). Other examples of cyclic (RAsO)n are n = 4 for R = Me (DiMaio & Rheingold, 1991), Ph (Muller & Muhle, 1999), mesityl (Arif et al., 1987) or 3-F3CC6H4 (Sun et al., 2005), and n = 5 for R = Et (Hausler & Sheldrick, 1997).

Experimental top

The title compound was prepared by hydrolysis of the dichloride 3-O2N-4-HOC6H3AsCl2, which in turn was prepared by reduction of 3-O2N-4-HOC6H3AsO3H2 with SO2 in conc HCl. Crystals suitable for X-ray analysis were obtained from an aqueous solution.

Refinement top

All H-atoms were positioned geometrically and refined using a riding model with C—H = 0.95 Å, Uiso(H) = 1.2Ueq(C) for aromatic and O—H = 0.84 Å, Uiso(H) = 1.5Ueq(O) for the OH groups. As only very small needle crystals were available, the data set was weak and so Rint and the final agreement factors are higher than usual. The highest residual electron density was 0.87Å from atom As1.

Computing details top

Data collection: SMART (Bruker 2001); cell refinement: SAINT (Bruker 2001); data reduction: SAINT (Bruker 2001); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound. Displacement ellipsoids are drawn at the 50% probability level. Dotted lines denote hydrogen bonds.
cyclo-Tetra-µ-oxido-tetra[3-nitro-4-hydroxyphenylarsenic(III)] top
Crystal data top
[As4O4(C6H4NO3)4]F000 = 1792
Mr = 916.09Dx = 2.091 Mg m−3
Monoclinic, P21/cMo Kα radiation
λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 4805 reflections
a = 7.1289 (2) Åθ = 2–25º
b = 31.6743 (9) ŵ = 4.64 mm−1
c = 13.0217 (4) ÅT = 93 (2) K
β = 98.286 (1)ºNeedle, yellow
V = 2909.64 (15) Å30.16 × 0.10 × 0.05 mm
Z = 4
Data collection top
Siemens SMART CCD
diffractometer		5490 independent reflections
Radiation source: fine-focus sealed tube3294 reflections with I > 2σ(I)
Monochromator: graphiteRint = 0.114
T = 93(2) Kθmax = 25.7º
φ and ω scansθmin = 1.7º
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)		h = −8→8
Tmin = 0.524, Tmax = 0.801k = −38→38
16032 measured reflectionsl = −11→15
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.068H-atom parameters constrained
wR(F2) = 0.131  w = 1/[σ2(Fo2) + (0.0328P)2 + 6.0469P]
where P = (Fo2 + 2Fc2)/3
S = 1.08(Δ/σ)max = 0.001
5490 reflectionsΔρmax = 1.03 e Å−3
433 parametersΔρmin = −0.91 e Å−3
Primary atom site location: structure-invariant direct methodsExtinction correction: none
Crystal data top
[As4O4(C6H4NO3)4]V = 2909.64 (15) Å3
Mr = 916.09Z = 4
Monoclinic, P21/cMo Kα
a = 7.1289 (2) ŵ = 4.64 mm−1
b = 31.6743 (9) ÅT = 93 (2) K
c = 13.0217 (4) Å0.16 × 0.10 × 0.05 mm
β = 98.286 (1)º
Data collection top
Siemens SMART CCD
diffractometer		5490 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)		3294 reflections with I > 2σ(I)
Tmin = 0.524, Tmax = 0.801Rint = 0.114
16032 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.068433 parameters
wR(F2) = 0.131H-atom parameters constrained
S = 1.08Δρmax = 1.03 e Å−3
5490 reflectionsΔρmin = −0.91 e Å−3
Special details top

Refinement. As only small needle crystals were available, the data set was weak and so the final agreement factors are higher than usual.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
As10.02562 (13)0.64613 (3)0.12402 (7)0.0189 (2)
As2−0.24608 (13)0.60197 (3)0.25665 (8)0.0204 (2)
As30.29993 (13)0.67460 (3)0.31865 (8)0.0212 (3)
As40.07624 (14)0.61371 (3)0.45063 (8)0.0236 (3)
N1−0.1904 (10)0.7965 (2)−0.0349 (7)0.0242 (19)
N2−0.3338 (12)0.5235 (3)−0.1123 (7)0.034 (2)
N30.2923 (12)0.8406 (3)0.2570 (7)0.039 (2)
N40.7762 (13)0.5809 (3)0.6360 (7)0.034 (2)
O1−0.2016 (8)0.64360 (17)0.1704 (5)0.0197 (14)
O2−0.0071 (8)0.59444 (18)0.3221 (5)0.0216 (15)
O30.1553 (8)0.66539 (18)0.4188 (5)0.0221 (15)
O40.1206 (8)0.68753 (17)0.2095 (5)0.0197 (15)
O11−0.2457 (8)0.76047 (19)−0.2455 (5)0.0241 (15)
H11−0.25510.7859−0.22880.036*
O12−0.2549 (8)0.82023 (19)−0.1079 (5)0.0262 (16)
O13−0.1622 (10)0.8085 (2)0.0547 (5)0.0325 (18)
O21−0.2054 (9)0.4438 (2)−0.0092 (6)0.0377 (19)
H21−0.24160.4477−0.07280.057*
O22−0.3260 (10)0.4912 (2)−0.1659 (6)0.043 (2)
O23−0.3879 (12)0.5576 (2)−0.1491 (6)0.049 (2)
O310.4044 (10)0.8558 (2)0.4784 (6)0.048 (2)
H310.38300.87360.43030.072*
O320.2570 (13)0.8322 (2)0.1640 (6)0.057 (2)
O330.2920 (11)0.8781 (2)0.2897 (6)0.052 (2)
O410.8297 (9)0.5182 (2)0.4778 (5)0.0338 (18)
H410.90700.52630.52880.051*
O420.7476 (10)0.6104 (2)0.6930 (5)0.040 (2)
O430.9213 (10)0.5587 (2)0.6485 (6)0.044 (2)
C11−0.0641 (12)0.6837 (3)0.0105 (7)0.019 (2)
C12−0.0898 (12)0.7266 (3)0.0266 (7)0.020 (2)
H12−0.06340.73830.09440.024*
C13−0.1554 (12)0.7524 (3)−0.0587 (7)0.017 (2)
C14−0.1879 (12)0.7370 (3)−0.1586 (7)0.021 (2)
C15−0.1662 (12)0.6946 (3)−0.1739 (7)0.021 (2)
H15−0.19320.6832−0.24200.026*
C16−0.1051 (12)0.6679 (3)−0.0911 (7)0.022 (2)
H16−0.09080.6385−0.10320.026*
C21−0.2211 (12)0.5540 (3)0.1643 (7)0.019 (2)
C22−0.2801 (12)0.5560 (3)0.0605 (7)0.022 (2)
H22−0.32360.58200.02930.027*
C23−0.2766 (12)0.5194 (3)−0.0008 (7)0.021 (2)
C24−0.2126 (13)0.4805 (3)0.0424 (8)0.028 (2)
C25−0.1569 (13)0.4790 (3)0.1489 (8)0.027 (2)
H25−0.11700.45290.18110.032*
C26−0.1591 (13)0.5148 (3)0.2082 (8)0.025 (2)
H26−0.11770.51320.28080.030*
C310.3370 (12)0.7330 (3)0.3635 (8)0.026 (2)
C320.3039 (12)0.7657 (3)0.2948 (9)0.028 (3)
H320.26400.76030.22320.034*
C330.3301 (13)0.8084 (3)0.3322 (9)0.034 (3)
C340.3886 (13)0.8159 (4)0.4376 (8)0.033 (3)
C350.4198 (13)0.7831 (4)0.5059 (9)0.038 (3)
H350.45860.78800.57780.045*
C360.3934 (12)0.7424 (3)0.4678 (8)0.027 (2)
H360.41510.71960.51540.032*
C410.3192 (13)0.5837 (3)0.4575 (7)0.022 (2)
C420.4625 (13)0.5922 (3)0.5381 (7)0.024 (2)
H420.44260.61280.58860.029*
C430.6336 (14)0.5715 (3)0.5465 (7)0.024 (2)
C440.6650 (14)0.5406 (3)0.4736 (7)0.025 (2)
C450.5206 (12)0.5315 (3)0.3945 (7)0.023 (2)
H450.53920.51020.34560.027*
C460.3488 (13)0.5527 (3)0.3846 (8)0.023 (2)
H460.25180.54630.32880.028*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
As10.0183 (5)0.0151 (5)0.0225 (6)0.0018 (4)0.0000 (4)−0.0001 (4)
As20.0208 (5)0.0148 (5)0.0253 (6)−0.0013 (4)0.0022 (4)−0.0004 (4)
As30.0167 (5)0.0169 (5)0.0281 (6)0.0021 (4)−0.0030 (4)−0.0031 (5)
As40.0259 (5)0.0211 (6)0.0227 (6)0.0022 (4)0.0002 (4)−0.0007 (4)
N10.016 (4)0.027 (5)0.029 (5)−0.003 (4)0.001 (4)−0.001 (4)
N20.024 (5)0.047 (6)0.031 (6)−0.019 (4)−0.003 (4)−0.001 (5)
N30.040 (6)0.038 (6)0.034 (6)−0.010 (5)−0.012 (5)0.008 (5)
N40.037 (5)0.032 (5)0.029 (5)−0.002 (4)−0.007 (4)0.009 (5)
O10.017 (3)0.012 (3)0.031 (4)−0.002 (3)0.005 (3)0.002 (3)
O20.024 (3)0.018 (3)0.020 (4)0.001 (3)−0.006 (3)−0.005 (3)
O30.026 (4)0.016 (3)0.023 (4)0.004 (3)0.001 (3)−0.004 (3)
O40.023 (3)0.014 (3)0.020 (4)0.003 (3)−0.003 (3)−0.002 (3)
O110.021 (3)0.026 (4)0.025 (4)−0.002 (3)0.000 (3)0.005 (3)
O120.021 (3)0.019 (4)0.036 (4)0.004 (3)−0.003 (3)0.013 (3)
O130.049 (5)0.023 (4)0.026 (4)0.002 (3)0.004 (4)−0.002 (3)
O210.039 (4)0.034 (4)0.038 (5)−0.002 (3)−0.001 (4)−0.019 (4)
O220.045 (5)0.056 (5)0.029 (5)−0.015 (4)0.008 (4)−0.023 (4)
O230.066 (6)0.046 (5)0.031 (5)−0.009 (4)−0.010 (4)0.008 (4)
O310.039 (4)0.019 (4)0.081 (6)0.007 (4)−0.005 (4)−0.017 (4)
O320.087 (7)0.041 (5)0.041 (6)−0.009 (5)0.001 (5)0.004 (4)
O330.067 (6)0.013 (4)0.073 (6)−0.009 (4)−0.005 (5)−0.001 (4)
O410.026 (4)0.035 (4)0.037 (5)0.009 (3)−0.005 (3)0.002 (4)
O420.052 (5)0.041 (5)0.025 (4)−0.004 (4)−0.002 (4)−0.010 (4)
O430.035 (4)0.049 (5)0.043 (5)0.011 (4)−0.016 (4)0.010 (4)
C110.017 (5)0.025 (6)0.016 (5)−0.003 (4)0.002 (4)0.005 (4)
C120.016 (5)0.028 (6)0.015 (5)−0.001 (4)0.004 (4)0.004 (4)
C130.019 (5)0.010 (5)0.022 (6)0.000 (4)0.007 (4)−0.001 (4)
C140.012 (5)0.034 (6)0.016 (6)−0.004 (4)0.001 (4)0.008 (4)
C150.017 (5)0.029 (6)0.019 (5)−0.010 (4)0.005 (4)−0.007 (5)
C160.014 (5)0.024 (6)0.028 (6)−0.001 (4)0.004 (4)−0.001 (5)
C210.018 (5)0.018 (5)0.019 (6)−0.008 (4)−0.001 (4)−0.008 (4)
C220.008 (4)0.024 (5)0.033 (6)−0.006 (4)0.001 (4)−0.005 (5)
C230.020 (5)0.032 (6)0.011 (5)−0.005 (4)−0.001 (4)0.001 (4)
C240.016 (5)0.031 (6)0.035 (7)−0.006 (4)0.003 (5)−0.012 (5)
C250.028 (6)0.020 (5)0.030 (6)0.009 (4)−0.005 (5)−0.001 (5)
C260.025 (5)0.024 (6)0.023 (6)0.001 (4)−0.003 (4)−0.007 (5)
C310.009 (5)0.019 (5)0.049 (7)−0.003 (4)0.005 (5)−0.008 (5)
C320.010 (5)0.026 (6)0.048 (7)−0.008 (4)0.003 (5)−0.008 (5)
C330.012 (5)0.030 (6)0.060 (8)0.000 (4)0.005 (5)0.013 (6)
C340.014 (5)0.050 (8)0.034 (7)−0.003 (5)0.004 (5)0.000 (6)
C350.015 (5)0.055 (8)0.046 (8)−0.003 (5)0.013 (5)−0.003 (6)
C360.013 (5)0.027 (6)0.041 (7)−0.001 (4)0.003 (5)−0.010 (5)
C410.030 (6)0.016 (5)0.020 (5)0.004 (4)−0.003 (4)0.006 (4)
C420.029 (6)0.019 (5)0.025 (6)0.006 (4)0.004 (5)0.006 (4)
C430.030 (6)0.022 (6)0.017 (5)−0.008 (4)−0.003 (5)0.003 (4)
C440.037 (6)0.021 (6)0.018 (6)0.005 (5)0.002 (5)0.009 (4)
C450.023 (5)0.022 (5)0.021 (6)−0.002 (4)−0.002 (4)−0.001 (4)
C460.023 (5)0.021 (5)0.025 (6)−0.004 (4)−0.001 (4)0.006 (5)
Geometric parameters (Å, °) top
As1—O41.789 (6)C12—C131.403 (12)
As1—O11.811 (6)C12—H120.9500
As1—C111.934 (9)C13—C141.377 (12)
As2—O11.790 (6)C14—C151.371 (13)
As2—O21.807 (6)C15—C161.391 (12)
As2—C211.962 (9)C15—H150.9500
As3—O31.799 (6)C16—H160.9500
As3—O41.816 (6)C21—C221.357 (12)
As3—C311.948 (9)C21—C261.411 (12)
As4—O31.799 (6)C22—C231.411 (12)
As4—O21.800 (6)C22—H220.9500
As4—C411.966 (9)C23—C241.402 (13)
N1—O131.216 (9)C24—C251.387 (13)
N1—O121.247 (9)C25—C261.376 (12)
N1—C131.461 (11)C25—H250.9500
N2—O231.219 (10)C26—H260.9500
N2—O221.243 (10)C31—C321.365 (13)
N2—C231.457 (12)C31—C361.391 (13)
N3—O321.229 (11)C32—C331.441 (14)
N3—O331.262 (10)C32—H320.9500
N3—C331.412 (13)C33—C341.396 (14)
N4—O421.227 (10)C34—C351.367 (14)
N4—O431.242 (10)C35—C361.383 (14)
N4—C431.463 (12)C35—H350.9500
O11—C141.367 (10)C36—H360.9500
O11—H110.8400C41—C421.382 (12)
O21—C241.349 (11)C41—C461.402 (13)
O21—H210.8400C42—C431.376 (13)
O31—C341.370 (12)C42—H420.9500
O31—H310.8400C43—C441.402 (13)
O41—C441.367 (11)C44—C451.378 (12)
O41—H410.8400C45—C461.387 (12)
C11—C121.391 (12)C45—H450.9500
C11—C161.405 (12)C46—H460.9500
O4—As1—O195.8 (3)C26—C21—As2118.9 (7)
O4—As1—C1194.5 (3)C21—C22—C23119.7 (9)
O1—As1—C1194.0 (3)C21—C22—H22120.1
O1—As2—O298.8 (3)C23—C22—H22120.1
O1—As2—C2198.4 (3)C24—C23—C22121.8 (9)
O2—As2—C2191.4 (3)C24—C23—N2120.5 (9)
O3—As3—O4101.0 (3)C22—C23—N2117.7 (9)
O3—As3—C3190.2 (4)O21—C24—C25116.2 (9)
O4—As3—C3194.0 (3)O21—C24—C23126.2 (9)
O3—As4—O299.6 (3)C25—C24—C23117.5 (9)
O3—As4—C4198.4 (3)C26—C25—C24120.5 (9)
O2—As4—C4192.8 (3)C26—C25—H25119.7
O13—N1—O12122.3 (8)C24—C25—H25119.7
O13—N1—C13119.7 (8)C25—C26—C21121.8 (9)
O12—N1—C13118.0 (8)C25—C26—H26119.1
O23—N2—O22123.0 (9)C21—C26—H26119.1
O23—N2—C23119.9 (9)C32—C31—C36118.5 (9)
O22—N2—C23117.1 (9)C32—C31—As3121.3 (8)
O32—N3—O33121.7 (9)C36—C31—As3120.2 (8)
O32—N3—C33121.3 (9)C31—C32—C33119.2 (10)
O33—N3—C33117.0 (9)C31—C32—H32120.4
O42—N4—O43124.0 (9)C33—C32—H32120.4
O42—N4—C43118.7 (8)C34—C33—N3124.0 (10)
O43—N4—C43117.2 (9)C34—C33—C32119.9 (10)
As2—O1—As1119.3 (3)N3—C33—C32116.1 (10)
As4—O2—As2123.8 (3)C35—C34—O31117.0 (10)
As3—O3—As4123.1 (3)C35—C34—C33120.5 (10)
As1—O4—As3118.8 (3)O31—C34—C33122.4 (10)
C14—O11—H11109.5C34—C35—C36118.3 (11)
C24—O21—H21109.5C34—C35—H35120.8
C34—O31—H31109.5C36—C35—H35120.8
C44—O41—H41109.5C35—C36—C31123.6 (10)
C12—C11—C16118.5 (8)C35—C36—H36118.2
C12—C11—As1121.5 (7)C31—C36—H36118.2
C16—C11—As1120.0 (7)C42—C41—C46119.0 (9)
C11—C12—C13118.9 (8)C42—C41—As4119.4 (7)
C11—C12—H12120.5C46—C41—As4121.6 (7)
C13—C12—H12120.5C43—C42—C41121.1 (9)
C14—C13—C12122.3 (8)C43—C42—H42119.5
C14—C13—N1121.9 (8)C41—C42—H42119.5
C12—C13—N1115.8 (8)C42—C43—C44120.4 (9)
O11—C14—C15116.1 (8)C42—C43—N4118.1 (9)
O11—C14—C13125.4 (9)C44—C43—N4121.5 (9)
C15—C14—C13118.5 (9)O41—C44—C45117.7 (9)
C14—C15—C16120.8 (9)O41—C44—C43123.7 (9)
C14—C15—H15119.6C45—C44—C43118.5 (9)
C16—C15—H15119.6C44—C45—C46121.5 (9)
C15—C16—C11120.8 (9)C44—C45—H45119.3
C15—C16—H16119.6C46—C45—H45119.3
C11—C16—H16119.6C45—C46—C41119.6 (9)
C22—C21—C26118.7 (8)C45—C46—H46120.2
C22—C21—As2122.1 (7)C41—C46—H46120.2
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
O11—H11···O120.841.912.614 (9)140
O21—H21···O220.841.882.579 (11)141
O31—H31···O330.841.862.572 (11)142
O41—H41···O430.841.862.569 (10)142
O11—H11···O1i0.842.653.260 (8)131
C15—H15···O42ii0.952.473.191 (12)132
C25—H25···O43iii0.952.473.151 (12)128
C15—H15···O13i0.952.703.539 (12)148
C12—H12···O11iv0.952.613.340 (11)134
C42—H42···O32iv0.952.483.355 (13)154
Symmetry codes: (i) x, −y+3/2, z−1/2; (ii) x−1, y, z−1; (iii) −x+1, −y+1, −z+1; (iv) x, −y+3/2, z+1/2.
Table 1
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
O11—H11···O120.841.912.614 (9)140
O21—H21···O220.841.882.579 (11)141
O31—H31···O330.841.862.572 (11)142
O41—H41···O430.841.862.569 (10)142
O11—H11···O1i0.842.653.260 (8)131
C15—H15···O42ii0.952.473.191 (12)132
C25—H25···O43iii0.952.473.151 (12)128
C15—H15···O13i0.952.703.539 (12)148
C12—H12···O11iv0.952.613.340 (11)134
C42—H42···O32iv0.952.483.355 (13)154
Symmetry codes: (i) x, −y+3/2, z−1/2; (ii) x−1, y, z−1; (iii) −x+1, −y+1, −z+1; (iv) x, −y+3/2, z+1/2.
Acknowledgements top

We thank Dr Tania Groutso, University of Auckland, for collection of X-ray intensity data. We also thank the Marsden Fund, administered by the Royal Society of New Zealand, for financial support.

references
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