N,N'-Di­hydroxy­benzene-1,2:4,5-tetra­carboximide dihydrate

In the title compound, C₁₀H₄N₂O₆·2H₂O, the organic mol­ecule has crystallographically imposed inversion symmetry. The atoms of the three fused rings of the mol­ecule are coplanar within 0.0246 (8) Å, while the two hy­droxy O atoms are displaced from the mean plane of the mol­ecule by 0.127 (1) Å. In the crystal, infinite near-planar layers of close-packed mol­ecules are formed by hydrogen bonding between water O-H donor groups and carbonyl O-atom acceptors, and by weak inter­actions between C-H donor groups and water O-atom acceptors. The layers are parallel to the {102} family of planes. The stacked planes are held together by hydrogen bonding between N-OH donor groups and water O-atom acceptors.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.002 Å
• R factor = 0.036
• wR factor = 0.100
• Data-to-parameter ratio = 12.3

checkCIF/PLATON results

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Alert level C
PLAT911_ALERT_3_C Missing # FCF Refl Between THmin & STh/L=  0.600          6
PLAT913_ALERT_3_C Missing # of Very Strong Reflections in FCF ....          1

Alert level G
PLAT005_ALERT_5_G No _iucr_refine_instructions_details  in the CIF          ? Do !
PLAT199_ALERT_1_G Check the Reported _cell_measurement_temperature        293 K
PLAT200_ALERT_1_G Check the Reported   _diffrn_ambient_temperature        293 K
PLAT912_ALERT_4_G Missing # of FCF Reflections Above STh/L=  0.600          5

   0 ALERT level A = Most likely a serious problem - resolve or explain
   0 ALERT level B = A potentially serious problem, consider carefully
   2 ALERT level C = Check. Ensure it is not caused by an omission or oversight
   4 ALERT level G = General information/check it is not something unexpected

   2 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   0 ALERT type 2 Indicator that the structure model may be wrong or deficient
   2 ALERT type 3 Indicator that the structure quality may be low
   1 ALERT type 4 Improvement, methodology, query or suggestion
   1 ALERT type 5 Informative message, check

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S1. Comment

The crystal engineering of structures containing stacked infinite planar layers of H bonded aromatic molecules is a hot research topic because of the potential interest of such structures as advanced materials in organic electronics, optoelectronics and photonics (Centore, Causà et al. 2013). Conjugated heterocyclic aromatic compounds are often used as building blocks for assembling active molecules for those advanced applications (Carella et al., 2004; Centore, Concilio et al., 2012). Aromatic diimides, in particular, are well known for their outstanding properties as n-type organic semiconductors (Centore, Ricciotti et al., 2012). Following these issues and our basic interest for crystal structures of conjugated heteroaromatic compounds conditioned by the formation of strong and weak H bonds (Centore et al., 2013a; 2013b) we report the structural investigation of the title compound, which is the dihydrate form of the N,N'-dihydroxy derivative of the simplest aromatic bis(imide).

The molecular structure is shown in Fig. 1. The organic molecule lies in special position on inversion centres and has point symmetry C_i. The atoms of the three fused rings of the molecule are coplanar within 0.0246 (8) Å, while the two hydroxy oxygen atoms are out of the average plane of the molecule by ±0.127 (1) Å. This is related with the torsion angle C2–C5–N1–O3 which is 171.9 (1)°, and would suggest a slight degree of pyramidalization at N1 (the sum of the valence angles around N1 is 359.1 (2)°). The two hydroxy H atoms are off the molecular plane because of the torsion angle C5–N1–O3–H3 = 80 (1)°.

Each organic molecule is in-plane surrounded by six water molecules. With four of them there are H bonds between O–H donors of the water molecules and carbonyl O acceptors of the diimide molecule. With the remaining two water molecules, there are weak interactions involving C–H donor and water O acceptor. Infinite planar layers of close-packed H bonded molecules are formed in this way, Fig. 2(a), in which ring patterns R⁴₄(14) and R⁴₄(15) are easily spotted. The layers are parallel to the family of planes with Miller indices (1 0 2), Fig. 2(b), and, in fact, the reflection (1 0 2) is the most intense of the whole diffraction pattern because, with the exception for the N–OH hydrogen atoms, all the atoms of the two molecules lie onto those planes. The stacked layers are held together by H bonds involving N–OH donors of a layer and water O acceptors of adjacent layers and this may account for the short interplanar spacing, d₁₀₂ = 2.99 Å. As it is clear from Fig. 2(b), adjacent stacked layers are related by a 2₁ screw operation, which is a very efficient way to fulfill the Kitaigorodskii's "bumps in hollows" golden rule of the close packing of layers (Kitaigorodskii, 1961).

Related literature

For semiconductor, optoelectronic and piezoelectric materials containing heterocycles, see: Centore, Ricciotti et al. (2012); Centore, Concilio et al. (2012). For the structural analysis of conjugation in organic molecules containing heterocycles, see: Carella et al. (2004). For the crystal packing of heterocycles containing nitrogen, see: Centore et al. (2013a,b). For the crystal engineering of structures containing stacked infinite planar layers, see: Centore, Causà et al. (2013). For the principle of close packing in organic crystallography, see: Kitaigorodskii (1961).

S2. Experimental

Hydroxylamine hydrochloride (3.18 g, 45.8 mmol) was added to pyridine (25 ml) and stirred at room temperature for 10 min until a clear solution was obtained. Pyromellitic anhydride (5.00 g, 22.9 mmol) was added and the solution was refluxed overnight. The solution was cooled to room temperature and the solid precipitate was filtered and washed with methanol and dried in oven at 120 °C for three days. Then it was poured in 100 ml of a solution methanol/conc. HCl (9:1 v/v). The suspension was left on stirring at gentle boiling for 1 h and then cooled to room temperature. The solid precipitate was filtered. The yield was 1.70 g (30%). ¹H-NMR (DMSO-d⁶, 200 MHz): 8.11 (2H, s, C–H); 11.14 (2H, s, N–OH).

Single crystals for X-ray analysis were obtained by slow evaporation of an ethanol/water (1:1 v/v) solution.

S3. Refinement

The H atoms bonded to O atoms were located in a difference Fourier map and their coordinates were refined. The H atom on benzene ring was generated stereochemically and was refined by the riding model. For all H atoms U_iso(H) = 1.2U_eq(C, O) was assumed.

Computing details

Data collection: COLLECT (Nonius, 1999); cell refinement: DIRAX/LSQ (Duisenberg et al., 2000); data reduction: EVALCCD (Duisenberg et al., 2003); program(s) used to solve structure: SIR97 (Altomare et al., 1999); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012) and Mercury (Macrae et al., 2006); software used to prepare material for publication: WinGX (Farrugia, 2012).

Figures

	Fig. 1. ORTEP view of the molecular structure of the title compound. Displacement ellipsoids are drawn at the 30% probability level. Symmetry code: (i) = -x, -y, -z.
	Fig. 2. Partial crystal packing of the title compound, showing some H bonding patterns. H bonds are represented by dashed lines; (a) front view of a layer of H bonded molecules; (b) edge view, along b, of two adjacent layers.

2,6-Dihydroxy-1H,2H,3H,5H,6H,7H-pyrrolo[3,4-f]isoindole-1,3,5,7-tetrone dihydrate

Crystal data

C10H4N2O6·2H2O	F(000) = 292
Mr = 284.18	Dx = 1.736 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 150 reflections
a = 6.874 (3) Å	θ = 4.9–23.6°
b = 10.189 (5) Å	µ = 0.15 mm^−1
c = 8.099 (4) Å	T = 293 K
β = 106.58 (2)°	Prism, yellow
V = 543.7 (4) Å^3	0.40 × 0.40 × 0.30 mm
Z = 2

Data collection

Bruker–Nonius KappaCCD diffractometer	1231 independent reflections
Radiation source: normal-focus sealed tube	1100 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.035
Detector resolution: 9 pixels mm^-1	θmax = 27.5°, θmin = 3.1°
CCD rotation images, thick slices scans	h = −8→8
Absorption correction: multi-scan (SADABS; Bruker, 2001)	k = −11→13
Tmin = 0.941, Tmax = 0.955	l = −10→9
4484 measured reflections

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.036	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.100	H atoms treated by a mixture of independent and constrained refinement
S = 1.09	w = 1/[σ^2(Fo^2) + (0.0519P)^2 + 0.137P] where P = (Fo^2 + 2Fc^2)/3
1231 reflections	(Δ/σ)max < 0.001
100 parameters	Δρmax = 0.22 e Å^−3
0 restraints	Δρmin = −0.25 e Å^−3

Special details

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes.

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
C1	0.10245 (17)	0.10697 (12)	−0.05619 (15)	0.0244 (3)
H1	0.1688	0.1760	−0.0924	0.029*
C2	−0.05331 (17)	0.12613 (11)	0.01756 (15)	0.0230 (3)
C3	−0.15149 (15)	0.02254 (11)	0.07171 (14)	0.0230 (3)
C4	−0.31036 (17)	0.07755 (12)	0.14333 (15)	0.0254 (3)
C5	−0.14618 (17)	0.25083 (12)	0.05285 (15)	0.0258 (3)
N1	−0.29927 (15)	0.21147 (11)	0.12231 (14)	0.0287 (3)
O1	−0.42607 (13)	0.02174 (10)	0.20623 (12)	0.0346 (3)
O2	−0.10464 (15)	0.36247 (8)	0.02877 (13)	0.0360 (3)
O3	−0.40708 (15)	0.29756 (10)	0.19205 (13)	0.0367 (3)
H3	−0.499 (3)	0.3314 (17)	0.103 (2)	0.044*
O4	0.32117 (15)	0.38853 (10)	−0.08642 (14)	0.0367 (3)
H4A	0.249 (2)	0.4570 (19)	−0.067 (2)	0.044*
H4B	0.387 (3)	0.4151 (18)	−0.163 (2)	0.044*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
C1	0.0234 (5)	0.0230 (6)	0.0280 (6)	−0.0016 (4)	0.0092 (4)	0.0017 (5)
C2	0.0226 (5)	0.0207 (5)	0.0255 (5)	0.0009 (4)	0.0063 (4)	0.0001 (4)
C3	0.0198 (5)	0.0255 (6)	0.0246 (5)	0.0000 (4)	0.0077 (4)	−0.0006 (4)
C4	0.0231 (5)	0.0285 (6)	0.0248 (5)	0.0012 (4)	0.0074 (4)	−0.0019 (4)
C5	0.0268 (6)	0.0245 (6)	0.0258 (5)	0.0030 (4)	0.0072 (4)	−0.0003 (5)
N1	0.0303 (5)	0.0264 (6)	0.0335 (5)	0.0068 (4)	0.0156 (4)	−0.0007 (4)
O1	0.0314 (5)	0.0382 (6)	0.0405 (5)	−0.0032 (4)	0.0202 (4)	−0.0014 (4)
O2	0.0436 (6)	0.0221 (5)	0.0451 (6)	0.0019 (4)	0.0170 (5)	0.0012 (4)
O3	0.0383 (5)	0.0379 (6)	0.0369 (5)	0.0155 (4)	0.0157 (4)	−0.0047 (4)
O4	0.0379 (5)	0.0324 (5)	0.0436 (6)	0.0011 (4)	0.0178 (4)	0.0028 (4)

Geometric parameters (Å, º)

C1—C3^i	1.3766 (17)	C4—N1	1.3799 (18)
C1—C2	1.3806 (17)	C5—O2	1.2022 (16)
C1—H1	0.9300	C5—N1	1.3866 (16)
C2—C3	1.3895 (16)	N1—O3	1.3699 (13)
C2—C5	1.4858 (16)	O3—H3	0.886 (19)
C3—C1^i	1.3766 (17)	O4—H4A	0.896 (19)
C3—C4	1.4848 (16)	O4—H4B	0.909 (19)
C4—O1	1.2028 (15)
C3^i—C1—C2	114.54 (11)	O1—C4—C3	129.49 (12)
C3^i—C1—H1	122.7	N1—C4—C3	104.62 (10)
C2—C1—H1	122.7	O2—C5—N1	125.62 (11)
C1—C2—C3	122.39 (11)	O2—C5—C2	130.01 (11)
C1—C2—C5	129.26 (11)	N1—C5—C2	104.37 (10)
C3—C2—C5	108.35 (11)	O3—N1—C4	121.80 (10)
C1^i—C3—C2	123.07 (11)	O3—N1—C5	123.00 (11)
C1^i—C3—C4	128.62 (11)	C4—N1—C5	114.27 (10)
C2—C3—C4	108.31 (11)	N1—O3—H3	105.0 (11)
O1—C4—N1	125.88 (11)	H4A—O4—H4B	107.4 (16)
C3^i—C1—C2—C3	0.13 (18)	C3—C2—C5—O2	178.61 (12)
C3^i—C1—C2—C5	−179.51 (11)	C1—C2—C5—N1	178.07 (11)
C1—C2—C3—C1^i	−0.1 (2)	C3—C2—C5—N1	−1.61 (13)
C5—C2—C3—C1^i	179.57 (10)	O1—C4—N1—O3	8.09 (19)
C1—C2—C3—C4	−179.69 (10)	C3—C4—N1—O3	−172.06 (10)
C5—C2—C3—C4	0.02 (12)	O1—C4—N1—C5	177.34 (11)
C1^i—C3—C4—O1	1.9 (2)	C3—C4—N1—C5	−2.80 (13)
C2—C3—C4—O1	−178.56 (12)	O2—C5—N1—O3	−8.29 (19)
C1^i—C3—C4—N1	−177.92 (11)	C2—C5—N1—O3	171.92 (10)
C2—C3—C4—N1	1.59 (12)	O2—C5—N1—C4	−177.40 (12)
C1—C2—C5—O2	−1.7 (2)	C2—C5—N1—C4	2.81 (13)

Symmetry code: (i) −x, −y, −z.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O3—H3···O4^ii	0.886 (19)	1.768 (19)	2.6516 (18)	175.2 (17)
O4—H4A···O2^iii	0.896 (19)	2.15 (2)	3.0441 (17)	172.4 (16)
O4—H4B···O1^iv	0.909 (19)	1.990 (19)	2.8879 (16)	169.3 (15)
C1—H1···O4	0.93	2.40	3.280 (2)	158

Symmetry codes: (ii) x−1, y, z; (iii) −x, −y+1, −z; (iv) x+1, −y+1/2, z−1/2.