A new layered zinc phosphate templated by protonated isonicotinate, [Zn₂(C₆H₅NO₂)₂(HPO₄)₂]

An organic-inorganic hybrid compound, poly­[bis­[(pyridine-4-carboxyl­ato)­zinc(II)]-di-[mu]₃-phosphato], [Zn₂(C₆H₅NO₂)₂(HPO₄)₂], has been hydro­thermally synthesized and structurally characterized. The crystal structure consists of two types of two-dimensional layers of zinc hydrogenphosphate templated by protonated isonicotinate (ina) (or 4-pyridine­carboxylic acid), which contain two crystallographically independent centrosymmetric [Zn₂(ina)₂(HPO4)₂] dimers as basic building units. The layers are interconnected via hydrogen-bonding and heterocyclic ring interactions.

S1. Comment

Because of the potential applications in catalysis, medicine and host–guest chemistry, inorganic metal oxides and salts structurally directed by polydentate organic ligands have attracted much attention (Leininger et al., 2000; Hagrman et al., 1999; Zhang et al., 2002; Yuan et al., 2002). In recent years, organically templated zinc phosphates have become a focus of much interest as a result of their rich structural and compositional diversity. A number of zinc phosphates with zero-, one-, two- and three-dimensional architectures have been constructed by employing solvothermal methods (Wang et al., 2003; Xing et al., 2004). In this paper, we report the hydrothermal synthesis and structural characterization of Zn₂(C₆H₅NO₂)₂(HPO₄)₂, (C₆H₅NO₂ = isonicotinate = ina), a novel organic–inorganic hybrid compound.

The asymmetric unit contains two crystallographically nonequivalent, but chemically identical, [Zn(ina)(HPO4)] groups. Each of these groups is bonded to another via a centrosymmetric junction to form two different dimers that can be regarded as the secondary building units of the structure (Fig. 1). These secondary building units are bonded to like units to form two distinct inorganic two-dimensional networks, a Zn1 layer and a Zn2 layer (Fig. 2). The centrosymmetric junctions are eight-membered rings comprising four tetrahedral centres (two Zn and two P) and four corner-shared bridging O atoms (Fig. 1). The Zn2O₄ unit is considerably distorted from a regular tetrahedron (Table 1). Each dimer is connected to four others in the same layer via an O bridging atom of PO₄ (O5 for the Zn1 layer and O9 for the Zn2 layer; Fig. 1) to form the two-dimensional inorganic networks composed of the eight-membered rings and larger 16-membered rings (4Zn, 4P and 8O; Fig. 2). The ina ligands are coordinated to Zn via one carboxylate O atom and extend on both sides of the networks (Figs. 2 and 3). There are strong intradimer hydorgen bonds between the HPO₄ units and the free carboxyl O atom of ina (Table 2). These bonds help control the steric relationship between the pyridine rings and the eight-membered inorganic rings.

The main difference between the two layers is that in the Zn1 layer all pyridine rings are parallel to one another (face-to-face arrangement), while in the Zn2 layer they have two orientations that are perpendicular to one another (face-to-edge arrangement). The Zn1 and Zn2 layers stack alternately in an.. ABAB.. fashion along the a axis to give rise to a three-dimensional structure (Fig. 3). The adjacent layers are interdigitated through ina rings to result in a tight packing. They are also connected via interlayer hydrogen bonding (Table 2).

The title compound contains N-protonated isonicotinate, [(H)NC₅H₄CO₂], which was not a starting reactant. It has been demonstrated that 4-cyanopyridine can be hydrolized slowly to yield isonicotinic acid under hydrothermal conditions (Evens et al., 1999). It is therefore very likely that the formation and crystal growth of the title compound was controlled by the hydrolyzation of 4-cyanopyridine.

S2. Experimental

All chemicals and solvents were of reagent grade and were used without further purification. The title compound was synthesized from a hydrothermal reaction of ZnO (0.600 g), 4-cyanopyridine (0.770 g), H₃PO₄ (85 w%, 1.00 ml) and H₂O (12.0 ml) in a 25 ml Teflon-lined stainless steel Parr bomb at 413 K for 3 d. Colorless block-like crystals were isolated and washed, in turn, with water, ethanol and anhydrous ether. IR (KBr disc, cm⁻¹): 3253.40 (w), 3104.20 (s), 2425.06 (w), 1609.01 (s), 1498.67 (w), 1403.81 (s), 1247.75 (m), 1200.04 (w), 1141.98 (s), 1072.69 (s), 1018.50 (s), 911.04 (m), 856.05 (w), 821.15 (w), 752.01 (m), 684.01 (m), 595.50 (s), 573.82 (m), 543.86 (w), 431.24 (m).

S3. Refinement

H atoms attached to N and O atoms were located from difference Fourier maps, and other H atoms were positioned geometrically. H atoms attached to N and C atoms were refined using a riding model, and those attached to O atoms were refined in fixed positions.

Computing details

Data collection: SMART (Bruker, 1997–2000); cell refinement: SMART; data reduction: SAINT (Siemens, 1995); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: XP (Siemens 1990); software used to prepare material for publication: SHELXL97.

Figures

	Fig. 1. The two centrosymmetric dimers that comprise the secondary building units of the (a) Zn1 and (b) Zn2 layers. Non-labelled atoms are related to the labelled ones by a centre of symmetry within the eight-membered rings. Displacement ellipsoids are at the 50% probability level. Symmetry codes in (a): (i) −x, 1/2 + y, 1/2 − z; in (b): (i) 1 − x, 1/2 + y, 1/2 − z.
	Fig. 2. (a) Zn1 and (b) Zn2 layers. The pyridine rings are all parallel in (a) but have two perpendicular arrangements in (b).
	Fig. 3. A view of the alternate stacking of the two distinct layers (Zn1 and Zn2). The layers are interdigitated by isonicotinic acid and interconnected by hydrogen bonds (not shown).

Poly[bis[(pyridine-4-carboxylato)zinc(II)]-di-µ₃-phosphato]

Crystal data

[Zn2(C6H5NO2)2(HPO4)2]	F(000) = 1136
Mr = 568.92	Dx = 2.096 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 4415 reflections
a = 20.560 (4) Å	θ = 2.6–31.9°
b = 8.5138 (17) Å	µ = 2.91 mm^−1
c = 10.387 (2) Å	T = 292 K
β = 97.46 (3)°	Block, colourless
V = 1802.8 (6) Å^3	0.20 × 0.20 × 0.15 mm
Z = 4

Data collection

Bruker SMART CCD area-detector diffractometer	6748 independent reflections
Radiation source: fine-focus sealed tube	5343 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.033
Detector resolution: 15X15 microns pixels mm^-1	θmax = 33.5°, θmin = 2.0°
ϕ and ω scans	h = −31→27
Absorption correction: empirical (using intensity measurements) (SADABS; Sheldrick 1996)	k = −13→10
Tmin = 0.564, Tmax = 0.646	l = −14→15
17073 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)] = 0.040	Hydrogen site location: difference Fourier map
wR(F^2) = 0.097	H-atom parameters constrained
S = 1.02	w = 1/[σ^2(Fo^2) + (0.0485P)^2] where P = (Fo^2 + 2Fc^2)/3
6748 reflections	(Δ/σ)max = 0.001
271 parameters	Δρmax = 0.84 e Å^−3
0 restraints	Δρmin = −0.41 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
Zn1	0.060200 (11)	0.41855 (3)	0.34836 (2)	0.01953 (7)
Zn2	0.435373 (11)	0.69146 (3)	0.07294 (2)	0.01955 (7)
P1	−0.02186 (3)	0.70972 (6)	0.39118 (5)	0.01833 (10)
P2	0.52407 (2)	0.40639 (6)	0.18276 (5)	0.01830 (10)
O1	0.34028 (7)	0.7064 (2)	0.07722 (19)	0.0344 (4)
O2	0.31375 (10)	0.5333 (3)	−0.0817 (3)	0.0645 (8)
O3	0.15645 (8)	0.4049 (2)	0.3655 (2)	0.0413 (5)
O4	0.19065 (9)	0.3779 (3)	0.5782 (2)	0.0481 (5)
O6	0.04142 (7)	0.63901 (19)	0.35893 (17)	0.0266 (3)
O8	0.45938 (7)	0.48255 (19)	0.13070 (16)	0.0250 (3)
O11	−0.07813 (8)	0.59388 (19)	0.33297 (18)	0.0310 (4)
H1O	−0.1141	0.6178	0.3603	0.037*
O12	0.57966 (7)	0.53603 (19)	0.18968 (17)	0.0270 (3)
H2O	0.6107	0.5067	0.1487	0.032*
N1	0.10409 (9)	0.6353 (3)	0.0813 (2)	0.0365 (5)
H1N	0.0642	0.6365	0.0978	0.044*
N2	0.39507 (9)	0.3894 (2)	0.3794 (2)	0.0299 (4)
H2N	0.4349	0.3894	0.3623	0.036*
C1	0.22999 (10)	0.6299 (3)	0.0309 (2)	0.0279 (5)
C2	0.18270 (11)	0.5379 (3)	−0.0416 (3)	0.0337 (5)
H2	0.1940	0.4737	−0.1077	0.040*
C3	0.11913 (11)	0.5430 (3)	−0.0141 (3)	0.0375 (6)
H3	0.0869	0.4824	−0.0617	0.045*
C4	0.14772 (12)	0.7257 (4)	0.1523 (3)	0.0403 (6)
H4	0.1349	0.7891	0.2174	0.048*
C5	0.21197 (11)	0.7246 (3)	0.1286 (3)	0.0356 (6)
H5	0.2430	0.7869	0.1778	0.043*
C6	0.30083 (11)	0.6217 (3)	0.0039 (3)	0.0325 (5)
C7	0.26933 (10)	0.3911 (3)	0.4331 (2)	0.0249 (4)
C8	0.32127 (11)	0.4059 (3)	0.5320 (3)	0.0308 (5)
H8	0.3135	0.4175	0.6177	0.037*
C9	0.38429 (11)	0.4029 (3)	0.5018 (3)	0.0335 (5)
H9	0.4195	0.4105	0.5675	0.040*
C10	0.34640 (11)	0.3756 (3)	0.2816 (3)	0.0333 (5)
H10	0.3559	0.3668	0.1967	0.040*
C11	0.28256 (11)	0.3745 (3)	0.3062 (3)	0.0320 (5)
H11	0.2485	0.3627	0.2386	0.038*
C12	0.19919 (11)	0.3916 (3)	0.4632 (3)	0.0290 (5)
O5	−0.03256 (8)	0.87138 (18)	0.33143 (16)	0.0274 (3)
O7	−0.02299 (7)	0.72513 (18)	0.53739 (15)	0.0240 (3)
O9	0.51956 (7)	0.35507 (18)	0.32299 (15)	0.0228 (3)
O10	0.54235 (8)	0.27031 (18)	0.10061 (15)	0.0248 (3)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Zn1	0.01798 (11)	0.02530 (13)	0.01586 (12)	0.00091 (8)	0.00427 (9)	0.00038 (8)
Zn2	0.01591 (11)	0.02595 (13)	0.01677 (12)	−0.00076 (8)	0.00198 (8)	−0.00141 (9)
P1	0.0192 (2)	0.0209 (2)	0.0156 (2)	0.00032 (18)	0.00509 (18)	−0.00047 (18)
P2	0.0174 (2)	0.0245 (3)	0.0132 (2)	0.00088 (18)	0.00266 (18)	0.00170 (18)
O1	0.0161 (7)	0.0441 (10)	0.0431 (11)	−0.0007 (7)	0.0036 (7)	−0.0052 (8)
O2	0.0284 (10)	0.0802 (16)	0.089 (2)	−0.0124 (10)	0.0245 (11)	−0.0482 (15)
O3	0.0163 (7)	0.0692 (14)	0.0385 (11)	0.0056 (8)	0.0042 (7)	0.0050 (9)
O4	0.0223 (8)	0.0885 (16)	0.0357 (12)	−0.0027 (10)	0.0122 (8)	0.0010 (11)
O6	0.0214 (7)	0.0261 (8)	0.0344 (10)	−0.0004 (6)	0.0110 (6)	−0.0036 (6)
O8	0.0197 (7)	0.0307 (8)	0.0240 (8)	0.0036 (6)	−0.0001 (6)	0.0065 (6)
O11	0.0239 (8)	0.0383 (10)	0.0321 (10)	−0.0061 (7)	0.0079 (7)	−0.0126 (7)
O12	0.0236 (7)	0.0304 (8)	0.0286 (9)	−0.0061 (6)	0.0099 (6)	−0.0043 (6)
N1	0.0152 (8)	0.0512 (13)	0.0440 (14)	0.0002 (8)	0.0073 (8)	0.0147 (10)
N2	0.0174 (8)	0.0377 (11)	0.0361 (12)	−0.0011 (7)	0.0088 (8)	−0.0023 (9)
C1	0.0164 (9)	0.0320 (11)	0.0358 (14)	0.0003 (8)	0.0054 (9)	0.0024 (9)
C2	0.0225 (10)	0.0366 (13)	0.0417 (15)	−0.0018 (9)	0.0035 (10)	−0.0025 (11)
C3	0.0217 (11)	0.0429 (14)	0.0472 (17)	−0.0072 (10)	0.0015 (10)	0.0067 (12)
C4	0.0272 (12)	0.0511 (17)	0.0452 (17)	0.0048 (11)	0.0142 (11)	−0.0020 (13)
C5	0.0222 (11)	0.0434 (15)	0.0424 (16)	−0.0004 (10)	0.0084 (10)	−0.0050 (11)
C6	0.0180 (9)	0.0370 (13)	0.0437 (16)	0.0010 (9)	0.0080 (9)	−0.0016 (11)
C7	0.0162 (9)	0.0291 (11)	0.0298 (12)	0.0013 (8)	0.0048 (8)	0.0008 (8)
C8	0.0223 (10)	0.0456 (14)	0.0255 (12)	−0.0008 (9)	0.0062 (9)	−0.0050 (10)
C9	0.0192 (10)	0.0480 (15)	0.0323 (14)	−0.0029 (9)	0.0000 (9)	−0.0066 (11)
C10	0.0265 (11)	0.0466 (14)	0.0282 (13)	0.0007 (10)	0.0089 (9)	−0.0009 (10)
C11	0.0195 (10)	0.0484 (14)	0.0278 (13)	−0.0002 (9)	0.0023 (9)	0.0028 (10)
C12	0.0190 (9)	0.0350 (12)	0.0340 (13)	−0.0003 (8)	0.0066 (9)	−0.0024 (10)
O5	0.0413 (9)	0.0240 (8)	0.0175 (8)	0.0057 (7)	0.0063 (7)	0.0022 (6)
O7	0.0274 (7)	0.0300 (8)	0.0149 (7)	−0.0016 (6)	0.0046 (6)	0.0018 (6)
O9	0.0210 (7)	0.0326 (8)	0.0156 (7)	0.0046 (6)	0.0051 (6)	0.0045 (6)
O10	0.0315 (8)	0.0266 (8)	0.0176 (8)	0.0020 (6)	0.0075 (6)	−0.0001 (6)

Geometric parameters (Å, º)

Zn1—O6	1.9222 (16)	N2—C9	1.323 (3)
Zn1—O5^i	1.9226 (17)	N2—C10	1.336 (3)
Zn1—O7^ii	1.9303 (16)	N2—H2N	0.8600
Zn1—O3	1.9671 (17)	C1—C5	1.384 (4)
Zn2—O8	1.9210 (16)	C1—C2	1.392 (3)
Zn2—O9^iii	1.9255 (15)	C1—C6	1.520 (3)
Zn2—O10^iv	1.9442 (16)	C2—C3	1.374 (3)
Zn2—O1	1.9656 (16)	C2—H2	0.9300
P1—O6	1.5103 (16)	C3—H3	0.9300
P1—O5	1.5140 (16)	C4—C5	1.375 (3)
P1—O7	1.5275 (16)	C4—H4	0.9300
P1—O11	1.5796 (16)	C5—H5	0.9300
P2—O10	1.5149 (16)	C7—C11	1.388 (3)
P2—O8	1.5150 (15)	C7—C8	1.388 (3)
P2—O9	1.5350 (16)	C7—C12	1.515 (3)
P2—O12	1.5837 (16)	C8—C9	1.372 (3)
O1—C6	1.264 (3)	C8—H8	0.9300
O2—C6	1.220 (3)	C9—H9	0.9300
O3—C12	1.258 (3)	C10—C11	1.369 (3)
O4—C12	1.236 (3)	C10—H10	0.9300
O11—H1O	0.8504	C11—H11	0.9300
O12—H2O	0.8495	O5—Zn1^v	1.9226 (17)
N1—C4	1.330 (4)	O7—Zn1^ii	1.9303 (16)
N1—C3	1.332 (4)	O9—Zn2^vi	1.9255 (15)
N1—H1N	0.8600	O10—Zn2^iv	1.9442 (16)
O6—Zn1—O5^i	102.90 (7)	C2—C1—C6	119.5 (2)
O6—Zn1—O7^ii	119.02 (7)	C3—C2—C1	119.1 (3)
O5^i—Zn1—O7^ii	111.97 (7)	C3—C2—H2	120.4
O6—Zn1—O3	105.05 (8)	C1—C2—H2	120.4
O5^i—Zn1—O3	104.05 (8)	N1—C3—C2	119.5 (2)
O7^ii—Zn1—O3	112.40 (8)	N1—C3—H3	120.3
O8—Zn2—O9^iii	114.15 (7)	C2—C3—H3	120.3
O8—Zn2—O10^iv	111.27 (7)	N1—C4—C5	119.4 (3)
O9^iii—Zn2—O10^iv	104.20 (7)	N1—C4—H4	120.3
O8—Zn2—O1	105.59 (7)	C5—C4—H4	120.3
O9^iii—Zn2—O1	110.38 (7)	C4—C5—C1	119.3 (2)
O10^iv—Zn2—O1	111.40 (8)	C4—C5—H5	120.3
O6—P1—O5	110.79 (10)	C1—C5—H5	120.3
O6—P1—O7	112.30 (10)	O2—C6—O1	127.4 (2)
O5—P1—O7	108.02 (9)	O2—C6—C1	117.9 (2)
O6—P1—O11	105.99 (9)	O1—C6—C1	114.7 (2)
O5—P1—O11	110.52 (10)	C11—C7—C8	119.0 (2)
O7—P1—O11	109.23 (10)	C11—C7—C12	120.4 (2)
O10—P2—O8	113.38 (9)	C8—C7—C12	120.5 (2)
O10—P2—O9	111.52 (9)	C9—C8—C7	119.2 (2)
O8—P2—O9	107.58 (9)	C9—C8—H8	120.4
O10—P2—O12	109.16 (9)	C7—C8—H8	120.4
O8—P2—O12	108.23 (9)	N2—C9—C8	120.1 (2)
O9—P2—O12	106.71 (9)	N2—C9—H9	119.9
C6—O1—Zn2	120.79 (16)	C8—C9—H9	119.9
C12—O3—Zn1	131.88 (18)	N2—C10—C11	120.0 (2)
P1—O6—Zn1	125.95 (10)	N2—C10—H10	120.0
P2—O8—Zn2	133.30 (10)	C11—C10—H10	120.0
P1—O11—H1O	110.4	C10—C11—C7	119.2 (2)
P2—O12—H2O	110.9	C10—C11—H11	120.4
C4—N1—C3	123.3 (2)	C7—C11—H11	120.4
C4—N1—H1N	118.4	O4—C12—O3	128.0 (2)
C3—N1—H1N	118.4	O4—C12—C7	117.3 (2)
C9—N2—C10	122.4 (2)	O3—C12—C7	114.7 (2)
C9—N2—H2N	118.8	P1—O5—Zn1^v	126.65 (10)
C10—N2—H2N	118.8	P1—O7—Zn1^ii	127.97 (10)
C5—C1—C2	119.4 (2)	P2—O9—Zn2^vi	130.89 (9)
C5—C1—C6	121.1 (2)	P2—O10—Zn2^iv	119.99 (9)
O8—Zn2—O1—C6	−64.3 (2)	C2—C1—C6—O2	0.0 (4)
O9^iii—Zn2—O1—C6	171.9 (2)	C5—C1—C6—O1	0.3 (4)
O10^iv—Zn2—O1—C6	56.6 (2)	C2—C1—C6—O1	−178.1 (2)
O6—Zn1—O3—C12	89.4 (2)	C11—C7—C8—C9	−0.3 (4)
O5^i—Zn1—O3—C12	−162.8 (2)	C12—C7—C8—C9	179.2 (2)
O7^ii—Zn1—O3—C12	−41.4 (3)	C10—N2—C9—C8	−1.1 (4)
O5—P1—O6—Zn1	−153.17 (12)	C7—C8—C9—N2	1.3 (4)
O7—P1—O6—Zn1	85.94 (14)	C9—N2—C10—C11	−0.3 (4)
O11—P1—O6—Zn1	−33.25 (16)	N2—C10—C11—C7	1.4 (4)
O5^i—Zn1—O6—P1	90.95 (14)	C8—C7—C11—C10	−1.1 (4)
O7^ii—Zn1—O6—P1	−33.51 (16)	C12—C7—C11—C10	179.5 (2)
O3—Zn1—O6—P1	−160.42 (13)	Zn1—O3—C12—O4	2.8 (4)
O10—P2—O8—Zn2	−119.85 (14)	Zn1—O3—C12—C7	−177.88 (16)
O9—P2—O8—Zn2	116.36 (14)	C11—C7—C12—O4	167.1 (2)
O12—P2—O8—Zn2	1.40 (17)	C8—C7—C12—O4	−12.3 (4)
O9^iii—Zn2—O8—P2	−40.16 (16)	C11—C7—C12—O3	−12.3 (3)
O10^iv—Zn2—O8—P2	77.42 (15)	C8—C7—C12—O3	168.3 (2)
O1—Zn2—O8—P2	−161.58 (13)	O6—P1—O5—Zn1^v	75.36 (15)
C5—C1—C2—C3	−0.1 (4)	O7—P1—O5—Zn1^v	−161.25 (11)
C6—C1—C2—C3	178.3 (2)	O11—P1—O5—Zn1^v	−41.81 (15)
C4—N1—C3—C2	0.6 (4)	O6—P1—O7—Zn1^ii	−95.66 (13)
C1—C2—C3—N1	−0.2 (4)	O5—P1—O7—Zn1^ii	141.87 (12)
C3—N1—C4—C5	−0.6 (4)	O11—P1—O7—Zn1^ii	21.62 (15)
N1—C4—C5—C1	0.3 (4)	O10—P2—O9—Zn2^vi	29.23 (16)
C2—C1—C5—C4	0.1 (4)	O8—P2—O9—Zn2^vi	154.15 (11)
C6—C1—C5—C4	−178.3 (3)	O12—P2—O9—Zn2^vi	−89.89 (14)
Zn2—O1—C6—O2	−5.9 (4)	O8—P2—O10—Zn2^iv	67.88 (13)
Zn2—O1—C6—C1	172.05 (16)	O9—P2—O10—Zn2^iv	−170.51 (9)
C5—C1—C6—O2	178.4 (3)	O12—P2—O10—Zn2^iv	−52.85 (13)

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

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O11—H1O···O4^ii	0.85	1.77	2.610 (2)	167.3
O12—H2O···O2^iv	0.85	1.81	2.655 (3)	169.6
N2—H2N···O8	0.86	2.64	3.153 (3)	119

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