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metal-organic compounds
Poly[piperazinium(2+) [hexa-μ-hydrogen phosphito-μ-piperazine-pentazinc(II)]]
aDepartment of Chemistry, University of Aberdeen, Aberdeen AB24 3UE, Scotland
*Correspondence e-mail: w.harrison@abdn.ac.uk
The title compound, {(C4H12N2)[Zn5(HPO3)6(C4H10N2)]}n contains ZnO4, ZnO3N and HPO3 polyhedral building units linked by Zn—O—P bridges (mean Zn—O—P = 133.6°). The organic species exists in two forms, i.e. as neutral molecules that bond directly to zinc as ligands via both N atoms and as diprotonated cations that interact with the framework by way of N—H⋯O hydrogen bonds. Both organic components lie across centres of inversion.
Comment
The title compound, (I), complements the growing family of organically templated zinc–hydrogen phosphite networks (Rodgers & Harrison, 2000
; Harrison, 2001
; Dong et al., 2003
; Lin et al., 2004
).
As shown in Fig. 1, there are five distinct Zn atoms in (I)
. Three of these metal ions are bonded to four O-atom neighbours in a tetrahedral geometry, and two (Zn4 and Zn5) are bonded to three O atoms and one N atom, the latter atom being part of a piperazine molecule. The mean Zn—O bond length [1.935 (3) Å] is typical for this family of phases (Harrison, 2001
), and the Zn—N bonds (Table 1
) are also characteristically longer (Kirkpatrick & Harrison, 2004
) than the Zn—O links.
The six P atoms all form the centres of tetrahedral [HPO3]2− anions. Because the P—H vertex of this species does not participate in chemical bonds, the shape of this group is often described as pseudo-pyramidal. The mean P—O bond length in (I) [1.516 (3) Å] and the narrow range of P—O distances [1.498 (3)–1.532 (3) Å] is normal (Lin et al., 2004
).
The 18 O atoms in (I) all exist as Zn—O—P bridges, with a mean bond angle of 133.6° [range 123.30 (17)–144.69 (19)°]; thus, in (I)
there are no terminal or `dangling' P=O or P—OH bonds, like those seen in some related phases (Harrison, 2001
). Also, there are no Zn—O—Zn or P—O—P bridges in (I)
.
The organic species exists in both neutral and diprotonated forms in (I). There are four distinct half-molecules in the (two neutral and two protonated). The four complete molecules are generated by inversion symmetry in every case and the resulting molecular conformations are typical six-membered-ring chairs. The neutral piperazine molecules (containing atoms N1 and N2) form ligand-like bonds to Zn atoms from both their N atoms, i.e. they act as framework bridges (Ritchie & Harrison, 2004
). The Zn atoms are in equatorial positions with respect to the six-membered ring, and the axial H atoms form N—H⋯O hydrogen bonds (Table 2
).
The two diprotonated piperazinium ions (containing atoms N3 and N4) interact with the zincophosphite network by way of N—H⋯O hydrogen bonds. Each N atom makes two N—H⋯O bonds [mean H⋯O = 1.97, mean N⋯O = 2.816 (4) Å and mean N—H⋯O = 159°] and occupies a polyhedral 12-ring (Fig. 2).
The complex structure of (I) can be decomposed into several distinctive subunits. However, the description presented here certainly is not intended to imply that these subunits necessarily play a well defined stepwise role in the formation of (I)
from small atomic/molecular units in solution. Firstly, the Zn1-, Zn2-, Zn3-, P2-, P5- and P6-centred polyhedra combine to form chains of alternating polyhedral six- (i.e. three ZnO4 tetrahedra + three HPO3 pseudo-pyramids) and four-rings propagating in the [101] direction (Fig. 3
). In turn, the P1 phosphite groups link to atoms Zn1 and Zn2, and thus crosslink the [101] chains into an infinite (010) sheet.
Considered in isolation, the Zn4- and P4-centred polyhedra and the N1-containing piperazine ring form a distinctive hybrid organic/inorganic chain propagating in [100]. The chain consists of inversion-symmetry-generated four-rings (two Zn4 + two P4), bridged by the piperazine molecules (Fig. 4). The Zn5 and P3 groups and the N2-containing piperazine species form a very similar chain that also propagates in the [100] direction. These two chains alternate with respect to the c direction.
When these subunits are conceptually assembled together, a complex three-dimensional framework results. There are lacunae in the hybrid organic/inorganic network that accommodate the N3- and N4-containing diprotonated piperazinium cations as described above. When viewed down [110], there appear to be channels present in the framework (Fig. 5). However, it is notable that, in every channel, the ligand-like and protonated organic species alternate; thus, it is extremely unlikely that the hydrogen-bonded piperazinium species could be removed without drastic changes in the hybrid framework.
Compound (I) complements several other piperazinium zinc phosphites, including (C4H12N2)[Zn6(HPO3)8]·2H3O (Dong et al., 2003
), (C4H12N2)[Zn3(HPO3)4] (Lin et al., 2004
) and (C4H12N2)[Zn(HPO3)2] (Shi et al., 2004
). These are more conventional templated networks in which the protonated organic species interacts with the inorganic network by way of N—H⋯O bonds (Cheetham et al., 1999
). Thus, as seen for other templating species, a wide variety of templated networks can arise (Kirkpatrick & Harrison, 2004
) for the same combination of metal, oxo-anion and template depending on synthesis conditions. Compound (I)
is particularly notable for the dual role – as a framework bridge and as a protonated template – played by the organic species.
![]() | Figure 1 A fragment of (I) ![]() |
![]() | Figure 2 The environment of the N3-containing piperazinium cation in (I) ![]() ![]() |
![]() | Figure 3 Part of an inorganic chain in (I) ![]() ![]() |
![]() | Figure 4 Part of a hybrid chain in (I) ![]() |
![]() | Figure 5 A polyhedral representation of the unit-cell packing for (I) ![]() |
Experimental
A mixture of ZnO (0.814 g, 10 mmol), H3PO3 (0.820 g, 10 mmol), piperazine hexahydrate (0.971 g, 5 mmol) and water (20 ml) was sealed in a plastic bottle and heated to 353 K for five days. After cooling to room temperature, colourless rods and blocks of (I) were recovered by vacuum filtration and washing with water and acetone.
Crystal data
|
Refinement
|
|
|
H atoms were located in difference maps and then placed in idealized locations (P—H = 1.32 Å, C—H = 0.97 Å, and N—H = 0.90 and 0.91 Å) and refined as riding, with Uiso(H) = 1.2Ueq(carrier).
Data collection: SMART (Bruker, 1999); cell SAINT (Bruker, 1999
); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997
); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997
); molecular graphics: ORTEP-3 (Farrugia, 1997
); software used to prepare material for publication: SHELXL97.
Supporting information
10.1107/S0108270106007657/gd3006sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock lg73t. DOI: 10.1107/S0108270106007657/gd3006Isup2.hkl
A mixture of ZnO (0.814 g, 10 mmol), H3PO3 (0.820 g, 10 mmol), piperazine hexahydrate (0.971 g, 5 mmol) and water (20 ml) was sealed in a plastic bottle and heated to 353 K for five days. After cooling to room temperature, colourless rods and blocks of (I) were recovered by vacuum filtration and washing with water and acetone.
H atoms were located in difference maps and then placed in idealized locations (P—H = 1.32 Å, C—H = 0.97 Å, and N—H = 0.90 and 0.91 Å) and refined as riding, with Uiso(H) = 1.2Ueq(carrier).
Data collection: SMART (Bruker, 1999); cell
SAINT (Bruker, 1999); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: SHELXL97.(C4H12N2)[Zn5(HPO3)6(C4H10N2) | Z = 2 |
Mr = 981.01 | F(000) = 976 |
Triclinic, P1 | Dx = 2.262 Mg m−3 |
Hall symbol: -P 1 | Mo Kα radiation, λ = 0.71073 Å |
a = 8.8634 (4) Å | Cell parameters from 4175 reflections |
b = 12.6390 (6) Å | θ = 2.2–30.0° |
c = 12.8768 (6) Å | µ = 4.52 mm−1 |
α = 89.182 (1)° | T = 293 K |
β = 89.913 (1)° | Rod, colourless |
γ = 86.941 (1)° | 0.13 × 0.07 × 0.06 mm |
V = 1440.31 (12) Å3 |
Bruker SMART 1000 CCD diffractometer | 8229 independent reflections |
Radiation source: fine-focus sealed tube | 5216 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.039 |
ω scans | θmax = 30.0°, θmin = 2.2° |
Absorption correction: multi-scan (SADABS; Bruker, 1999) | h = −12→12 |
Tmin = 0.583, Tmax = 0.763 | k = −17→17 |
16520 measured reflections | l = −18→17 |
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)] = 0.040 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.077 | H-atom parameters constrained |
S = 0.90 | w = 1/[σ2(Fo2) + (0.0273P)2] where P = (Fo2 + 2Fc2)/3 |
8229 reflections | (Δ/σ)max < 0.001 |
370 parameters | Δρmax = 1.14 e Å−3 |
0 restraints | Δρmin = −0.59 e Å−3 |
(C4H12N2)[Zn5(HPO3)6(C4H10N2) | γ = 86.941 (1)° |
Mr = 981.01 | V = 1440.31 (12) Å3 |
Triclinic, P1 | Z = 2 |
a = 8.8634 (4) Å | Mo Kα radiation |
b = 12.6390 (6) Å | µ = 4.52 mm−1 |
c = 12.8768 (6) Å | T = 293 K |
α = 89.182 (1)° | 0.13 × 0.07 × 0.06 mm |
β = 89.913 (1)° |
Bruker SMART 1000 CCD diffractometer | 8229 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 1999) | 5216 reflections with I > 2σ(I) |
Tmin = 0.583, Tmax = 0.763 | Rint = 0.039 |
16520 measured reflections |
R[F2 > 2σ(F2)] = 0.040 | 0 restraints |
wR(F2) = 0.077 | H-atom parameters constrained |
S = 0.90 | Δρmax = 1.14 e Å−3 |
8229 reflections | Δρmin = −0.59 e Å−3 |
370 parameters |
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. |
x | y | z | Uiso*/Ueq | ||
Zn1 | 0.58057 (5) | 0.60145 (4) | 0.61549 (4) | 0.02379 (11) | |
Zn2 | 1.05294 (5) | 0.60445 (4) | 0.88464 (4) | 0.02315 (11) | |
Zn3 | 0.75704 (5) | 0.22882 (4) | 0.75293 (3) | 0.02176 (11) | |
Zn4 | 0.66727 (5) | 0.91001 (4) | 0.90014 (4) | 0.02276 (11) | |
Zn5 | 0.83361 (5) | 0.11580 (4) | 0.43915 (4) | 0.02166 (11) | |
P1 | 0.29585 (11) | 0.71177 (8) | 0.72813 (8) | 0.0210 (2) | |
H1 | 0.3831 | 0.7900 | 0.7497 | 0.025* | |
P2 | 0.80154 (11) | 0.73085 (8) | 0.75991 (8) | 0.0217 (2) | |
H2 | 0.9144 | 0.7829 | 0.7210 | 0.026* | |
P3 | 1.01828 (12) | 0.09579 (8) | 0.65812 (8) | 0.0224 (2) | |
H3 | 1.1239 | 0.1575 | 0.6901 | 0.027* | |
P5 | 0.98326 (13) | 0.37003 (9) | 0.86947 (8) | 0.0256 (2) | |
H5 | 1.0704 | 0.2832 | 0.8844 | 0.031* | |
P4 | 0.47874 (12) | 0.13830 (8) | 0.87516 (8) | 0.0231 (2) | |
H4 | 0.3827 | 0.1663 | 0.8002 | 0.028* | |
P6 | 0.53186 (12) | 0.35199 (8) | 0.60917 (8) | 0.0232 (2) | |
H6 | 0.4498 | 0.3680 | 0.6937 | 0.028* | |
O11 | 0.1944 (3) | 0.7493 (2) | 0.6375 (2) | 0.0274 (6) | |
O12 | 0.2110 (3) | 0.6860 (2) | 0.8264 (2) | 0.0334 (7) | |
O13 | 0.3989 (3) | 0.6181 (2) | 0.6964 (2) | 0.0380 (8) | |
O21 | 0.6762 (3) | 0.8129 (2) | 0.7858 (2) | 0.0313 (7) | |
O22 | 0.7563 (3) | 0.6549 (3) | 0.6785 (2) | 0.0454 (9) | |
O23 | 0.8601 (3) | 0.6740 (3) | 0.8573 (2) | 0.0373 (8) | |
O31 | 1.0892 (4) | −0.0150 (2) | 0.6602 (2) | 0.0434 (9) | |
O32 | 0.8929 (3) | 0.1047 (2) | 0.7392 (2) | 0.0326 (7) | |
O33 | 0.9699 (3) | 0.1384 (2) | 0.5521 (2) | 0.0314 (7) | |
O41 | 0.6098 (3) | 0.2119 (2) | 0.8642 (2) | 0.0323 (7) | |
O42 | 0.5249 (3) | 0.0237 (2) | 0.8574 (2) | 0.0364 (8) | |
O43 | 0.3974 (4) | 0.1620 (2) | 0.9749 (2) | 0.0408 (8) | |
O51 | 1.0863 (3) | 0.4583 (2) | 0.8435 (2) | 0.0328 (7) | |
O52 | 0.8777 (4) | 0.3486 (2) | 0.7800 (2) | 0.0361 (8) | |
O53 | 0.8933 (3) | 0.3887 (3) | 0.9691 (2) | 0.0351 (8) | |
O61 | 0.4234 (3) | 0.3337 (2) | 0.5215 (2) | 0.0380 (8) | |
O62 | 0.6249 (3) | 0.4496 (2) | 0.5933 (2) | 0.0300 (7) | |
O63 | 0.6348 (3) | 0.2542 (2) | 0.6296 (2) | 0.0325 (7) | |
N1 | 0.8661 (3) | 0.9790 (2) | 0.9365 (2) | 0.0211 (7) | |
H1A | 0.8793 | 1.0300 | 0.8872 | 0.025* | |
C1 | 1.0053 (5) | 0.9083 (3) | 0.9357 (4) | 0.0329 (11) | |
H1B | 1.0176 | 0.8776 | 0.8674 | 0.040* | |
H1C | 0.9941 | 0.8508 | 0.9853 | 0.040* | |
C2 | 0.8537 (5) | 1.0344 (4) | 1.0377 (3) | 0.0343 (11) | |
H2B | 0.8351 | 0.9829 | 1.0923 | 0.041* | |
H2C | 0.7678 | 1.0852 | 1.0353 | 0.041* | |
N2 | 0.6290 (4) | 0.0694 (3) | 0.4905 (2) | 0.0225 (7) | |
H2A | 0.5943 | 0.1194 | 0.5361 | 0.027* | |
C3 | 0.5128 (5) | 0.0647 (5) | 0.4097 (4) | 0.0470 (14) | |
H3C | 0.5478 | 0.0143 | 0.3577 | 0.056* | |
H3D | 0.4998 | 0.1336 | 0.3759 | 0.056* | |
C4 | 0.6397 (5) | −0.0328 (4) | 0.5493 (4) | 0.0439 (13) | |
H4C | 0.7084 | −0.0268 | 0.6072 | 0.053* | |
H4D | 0.6814 | −0.0879 | 0.5044 | 0.053* | |
N3 | 0.9023 (4) | 0.4150 (3) | 0.4853 (3) | 0.0335 (9) | |
H3A | 0.8827 | 0.3537 | 0.4545 | 0.040* | |
H3B | 0.8236 | 0.4332 | 0.5267 | 0.040* | |
C5 | 1.0398 (5) | 0.3985 (4) | 0.5494 (3) | 0.0339 (11) | |
H5A | 1.1222 | 0.3697 | 0.5069 | 0.041* | |
H5B | 1.0219 | 0.3478 | 0.6047 | 0.041* | |
C6 | 0.9171 (5) | 0.4983 (4) | 0.4045 (3) | 0.0340 (11) | |
H6A | 0.8219 | 0.5095 | 0.3679 | 0.041* | |
H6B | 0.9934 | 0.4749 | 0.3547 | 0.041* | |
N4 | 0.5710 (4) | 0.4009 (3) | 0.9699 (3) | 0.0309 (8) | |
H4A | 0.6611 | 0.4022 | 1.0018 | 0.037* | |
H4B | 0.5690 | 0.3398 | 0.9349 | 0.037* | |
C7 | 0.4492 (5) | 0.4049 (3) | 1.0487 (3) | 0.0338 (11) | |
H7A | 0.4661 | 0.3472 | 1.0984 | 0.041* | |
H7B | 0.3526 | 0.3967 | 1.0152 | 0.041* | |
C8 | 0.5538 (6) | 0.4910 (3) | 0.8960 (3) | 0.0369 (11) | |
H8A | 0.4608 | 0.4861 | 0.8572 | 0.044* | |
H8B | 0.6371 | 0.4877 | 0.8470 | 0.044* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Zn1 | 0.0240 (2) | 0.0230 (3) | 0.0241 (3) | 0.00284 (19) | −0.00203 (19) | −0.0049 (2) |
Zn2 | 0.0229 (2) | 0.0268 (3) | 0.0199 (2) | −0.00321 (19) | −0.00083 (19) | 0.0014 (2) |
Zn3 | 0.0252 (2) | 0.0203 (2) | 0.0195 (2) | 0.00133 (19) | 0.00315 (19) | −0.00139 (19) |
Zn4 | 0.0204 (2) | 0.0220 (2) | 0.0262 (3) | −0.00298 (18) | 0.00162 (19) | −0.0058 (2) |
Zn5 | 0.0208 (2) | 0.0193 (2) | 0.0249 (3) | −0.00121 (18) | 0.00180 (19) | 0.0003 (2) |
P1 | 0.0191 (5) | 0.0218 (5) | 0.0222 (5) | −0.0039 (4) | 0.0029 (4) | 0.0015 (4) |
P2 | 0.0192 (5) | 0.0236 (6) | 0.0226 (5) | −0.0010 (4) | −0.0002 (4) | −0.0079 (4) |
P3 | 0.0223 (5) | 0.0237 (6) | 0.0208 (5) | 0.0014 (4) | 0.0004 (4) | −0.0035 (4) |
P5 | 0.0350 (6) | 0.0213 (6) | 0.0211 (6) | −0.0061 (5) | 0.0004 (5) | 0.0006 (5) |
P4 | 0.0246 (5) | 0.0193 (5) | 0.0250 (6) | 0.0016 (4) | 0.0023 (4) | −0.0005 (4) |
P6 | 0.0259 (5) | 0.0231 (6) | 0.0202 (5) | 0.0019 (4) | −0.0004 (4) | −0.0002 (4) |
O11 | 0.0308 (16) | 0.0194 (15) | 0.0322 (16) | −0.0050 (12) | −0.0056 (13) | 0.0043 (13) |
O12 | 0.0359 (17) | 0.0386 (19) | 0.0269 (17) | −0.0129 (14) | 0.0132 (13) | 0.0002 (14) |
O13 | 0.0318 (17) | 0.0388 (19) | 0.0420 (19) | 0.0118 (14) | 0.0085 (15) | 0.0023 (15) |
O21 | 0.0322 (17) | 0.0289 (17) | 0.0317 (16) | 0.0099 (13) | −0.0076 (13) | −0.0109 (13) |
O22 | 0.0317 (18) | 0.049 (2) | 0.055 (2) | 0.0078 (15) | −0.0137 (15) | −0.0388 (18) |
O23 | 0.0257 (16) | 0.052 (2) | 0.0332 (18) | 0.0086 (15) | −0.0001 (13) | 0.0039 (15) |
O31 | 0.057 (2) | 0.0365 (19) | 0.0341 (18) | 0.0228 (16) | 0.0081 (16) | −0.0058 (15) |
O32 | 0.0354 (17) | 0.0290 (17) | 0.0317 (17) | 0.0114 (13) | 0.0125 (13) | 0.0060 (14) |
O33 | 0.0304 (16) | 0.0418 (19) | 0.0224 (15) | −0.0054 (14) | −0.0021 (13) | 0.0032 (14) |
O41 | 0.0361 (17) | 0.0289 (17) | 0.0330 (17) | −0.0086 (13) | 0.0175 (14) | −0.0083 (14) |
O42 | 0.0370 (18) | 0.0189 (16) | 0.053 (2) | 0.0049 (13) | −0.0088 (15) | −0.0111 (15) |
O43 | 0.051 (2) | 0.0311 (18) | 0.0409 (19) | −0.0058 (15) | 0.0267 (16) | −0.0040 (15) |
O51 | 0.0396 (18) | 0.0269 (17) | 0.0332 (17) | −0.0127 (14) | 0.0107 (14) | −0.0040 (14) |
O52 | 0.051 (2) | 0.0341 (18) | 0.0245 (16) | −0.0173 (15) | −0.0031 (14) | −0.0022 (14) |
O53 | 0.0350 (17) | 0.053 (2) | 0.0182 (15) | −0.0121 (15) | −0.0032 (13) | 0.0031 (14) |
O61 | 0.0374 (18) | 0.043 (2) | 0.0347 (18) | −0.0117 (15) | −0.0113 (14) | 0.0123 (15) |
O62 | 0.0308 (16) | 0.0184 (15) | 0.0408 (18) | 0.0004 (12) | 0.0008 (14) | −0.0052 (13) |
O63 | 0.0460 (19) | 0.0204 (15) | 0.0301 (17) | 0.0085 (13) | −0.0104 (14) | −0.0041 (13) |
N1 | 0.0221 (17) | 0.0199 (18) | 0.0220 (17) | −0.0074 (13) | −0.0011 (14) | 0.0014 (14) |
C1 | 0.029 (2) | 0.031 (3) | 0.039 (3) | −0.0001 (19) | −0.0061 (19) | −0.018 (2) |
C2 | 0.024 (2) | 0.042 (3) | 0.038 (3) | −0.004 (2) | −0.0025 (19) | −0.015 (2) |
N2 | 0.0262 (18) | 0.0178 (17) | 0.0243 (18) | −0.0062 (14) | 0.0048 (14) | −0.0064 (14) |
C3 | 0.032 (3) | 0.074 (4) | 0.036 (3) | −0.024 (3) | −0.005 (2) | 0.024 (3) |
C4 | 0.028 (2) | 0.050 (3) | 0.054 (3) | −0.013 (2) | −0.009 (2) | 0.030 (3) |
N3 | 0.034 (2) | 0.023 (2) | 0.045 (2) | −0.0100 (16) | 0.0022 (18) | −0.0087 (17) |
C5 | 0.040 (3) | 0.029 (2) | 0.032 (3) | 0.001 (2) | 0.001 (2) | 0.002 (2) |
C6 | 0.039 (3) | 0.037 (3) | 0.027 (2) | −0.007 (2) | −0.005 (2) | −0.001 (2) |
N4 | 0.0290 (19) | 0.0252 (19) | 0.038 (2) | 0.0026 (15) | 0.0009 (16) | −0.0124 (17) |
C7 | 0.038 (3) | 0.026 (2) | 0.037 (3) | −0.0008 (19) | 0.012 (2) | 0.001 (2) |
C8 | 0.053 (3) | 0.028 (3) | 0.029 (2) | 0.002 (2) | 0.017 (2) | −0.003 (2) |
Zn1—O22 | 1.917 (3) | O12—Zn2vii | 1.927 (3) |
Zn1—O13 | 1.920 (3) | O31—Zn5vi | 1.918 (3) |
Zn1—O61i | 1.934 (3) | O42—Zn4viii | 1.935 (3) |
Zn1—O62 | 1.963 (3) | O43—Zn4v | 1.939 (3) |
Zn2—O23 | 1.910 (3) | O53—Zn2iii | 1.947 (3) |
Zn2—O12ii | 1.927 (3) | O61—Zn1i | 1.934 (3) |
Zn2—O51 | 1.936 (3) | N1—C1 | 1.484 (5) |
Zn2—O53iii | 1.947 (3) | N1—C2 | 1.490 (5) |
Zn3—O52 | 1.935 (3) | N1—H1A | 0.9100 |
Zn3—O32 | 1.936 (3) | C1—C2ix | 1.520 (6) |
Zn3—O63 | 1.937 (3) | C1—H1B | 0.9700 |
Zn3—O41 | 1.953 (3) | C1—H1C | 0.9700 |
Zn4—O21 | 1.929 (3) | C2—C1ix | 1.520 (6) |
Zn4—O42iv | 1.935 (3) | C2—H2B | 0.9700 |
Zn4—O43v | 1.939 (3) | C2—H2C | 0.9700 |
Zn4—N1 | 2.065 (3) | N2—C3 | 1.469 (5) |
Zn5—O31vi | 1.918 (3) | N2—C4 | 1.486 (5) |
Zn5—O33 | 1.927 (3) | N2—H2A | 0.9100 |
Zn5—O11i | 1.962 (3) | C3—C4x | 1.522 (6) |
Zn5—N2 | 2.042 (3) | C3—H3C | 0.9700 |
P1—O12 | 1.512 (3) | C3—H3D | 0.9700 |
P1—O13 | 1.517 (3) | C4—C3x | 1.522 (6) |
P1—O11 | 1.529 (3) | C4—H4C | 0.9700 |
P1—H1 | 1.3200 | C4—H4D | 0.9700 |
P2—O22 | 1.501 (3) | N3—C5 | 1.477 (5) |
P2—O23 | 1.515 (3) | N3—C6 | 1.480 (5) |
P2—O21 | 1.519 (3) | N3—H3A | 0.9000 |
P2—H2 | 1.3200 | N3—H3B | 0.9000 |
P3—O31 | 1.504 (3) | C5—C6xi | 1.508 (6) |
P3—O33 | 1.514 (3) | C5—H5A | 0.9700 |
P3—O32 | 1.524 (3) | C5—H5B | 0.9700 |
P3—H3 | 1.3200 | C6—C5xi | 1.508 (6) |
P5—O51 | 1.513 (3) | C6—H6A | 0.9700 |
P5—O52 | 1.522 (3) | C6—H6B | 0.9700 |
P5—O53 | 1.524 (3) | N4—C8 | 1.475 (5) |
P5—H5 | 1.3200 | N4—C7 | 1.480 (5) |
P4—O43 | 1.498 (3) | N4—H4A | 0.9000 |
P4—O42 | 1.505 (3) | N4—H4B | 0.9000 |
P4—O41 | 1.532 (3) | C7—C8v | 1.504 (6) |
P4—H4 | 1.3200 | C7—H7A | 0.9700 |
P6—O61 | 1.512 (3) | C7—H7B | 0.9700 |
P6—O63 | 1.517 (3) | C8—C7v | 1.504 (6) |
P6—O62 | 1.531 (3) | C8—H8A | 0.9700 |
P6—H6 | 1.3200 | C8—H8B | 0.9700 |
O11—Zn5i | 1.962 (3) | ||
O22—Zn1—O13 | 114.90 (13) | P5—O51—Zn2 | 125.14 (17) |
O22—Zn1—O61i | 103.70 (14) | P5—O52—Zn3 | 130.99 (19) |
O13—Zn1—O61i | 116.69 (13) | P5—O53—Zn2iii | 134.11 (19) |
O22—Zn1—O62 | 106.78 (13) | P6—O61—Zn1i | 127.73 (19) |
O13—Zn1—O62 | 108.43 (13) | P6—O62—Zn1 | 132.85 (17) |
O61i—Zn1—O62 | 105.56 (13) | P6—O63—Zn3 | 125.10 (17) |
O23—Zn2—O12ii | 110.10 (13) | C1—N1—C2 | 109.5 (3) |
O23—Zn2—O51 | 118.36 (14) | C1—N1—Zn4 | 116.3 (2) |
O12ii—Zn2—O51 | 108.82 (12) | C2—N1—Zn4 | 111.2 (2) |
O23—Zn2—O53iii | 111.56 (13) | C1—N1—H1A | 106.4 |
O12ii—Zn2—O53iii | 99.06 (13) | C2—N1—H1A | 106.4 |
O51—Zn2—O53iii | 107.18 (13) | Zn4—N1—H1A | 106.4 |
O52—Zn3—O32 | 107.92 (14) | N1—C1—C2ix | 112.8 (3) |
O52—Zn3—O63 | 110.81 (13) | N1—C1—H1B | 109.0 |
O32—Zn3—O63 | 111.64 (12) | C2ix—C1—H1B | 109.0 |
O52—Zn3—O41 | 110.23 (12) | N1—C1—H1C | 109.0 |
O32—Zn3—O41 | 112.09 (12) | C2ix—C1—H1C | 109.0 |
O63—Zn3—O41 | 104.17 (13) | H1B—C1—H1C | 107.8 |
O21—Zn4—O42iv | 105.25 (12) | N1—C2—C1ix | 112.8 (3) |
O21—Zn4—O43v | 109.86 (13) | N1—C2—H2B | 109.0 |
O42iv—Zn4—O43v | 112.16 (13) | C1ix—C2—H2B | 109.0 |
O21—Zn4—N1 | 116.26 (13) | N1—C2—H2C | 109.0 |
O42iv—Zn4—N1 | 106.77 (13) | C1ix—C2—H2C | 109.0 |
O43v—Zn4—N1 | 106.62 (14) | H2B—C2—H2C | 107.8 |
O31vi—Zn5—O33 | 113.98 (13) | C3—N2—C4 | 109.3 (4) |
O31vi—Zn5—O11i | 105.62 (13) | C3—N2—Zn5 | 114.9 (3) |
O33—Zn5—O11i | 107.15 (12) | C4—N2—Zn5 | 113.0 (3) |
O31vi—Zn5—N2 | 108.36 (14) | C3—N2—H2A | 106.3 |
O33—Zn5—N2 | 112.03 (13) | C4—N2—H2A | 106.3 |
O11i—Zn5—N2 | 109.44 (12) | Zn5—N2—H2A | 106.3 |
O12—P1—O13 | 110.55 (18) | N2—C3—C4x | 113.7 (4) |
O12—P1—O11 | 114.12 (17) | N2—C3—H3C | 108.8 |
O13—P1—O11 | 110.46 (17) | C4x—C3—H3C | 108.8 |
O12—P1—H1 | 107.1 | N2—C3—H3D | 108.8 |
O13—P1—H1 | 107.1 | C4x—C3—H3D | 108.8 |
O11—P1—H1 | 107.1 | H3C—C3—H3D | 107.7 |
O22—P2—O23 | 112.0 (2) | N2—C4—C3x | 112.5 (4) |
O22—P2—O21 | 112.80 (17) | N2—C4—H4C | 109.1 |
O23—P2—O21 | 110.84 (16) | C3x—C4—H4C | 109.1 |
O22—P2—H2 | 106.9 | N2—C4—H4D | 109.1 |
O23—P2—H2 | 106.9 | C3x—C4—H4D | 109.1 |
O21—P2—H2 | 106.9 | H4C—C4—H4D | 107.8 |
O31—P3—O33 | 115.57 (17) | C5—N3—C6 | 112.5 (3) |
O31—P3—O32 | 109.40 (17) | C5—N3—H3A | 109.1 |
O33—P3—O32 | 113.35 (16) | C6—N3—H3A | 109.1 |
O31—P3—H3 | 105.9 | C5—N3—H3B | 109.1 |
O33—P3—H3 | 105.9 | C6—N3—H3B | 109.1 |
O32—P3—H3 | 105.9 | H3A—N3—H3B | 107.8 |
O51—P5—O52 | 111.88 (17) | N3—C5—C6xi | 110.5 (3) |
O51—P5—O53 | 113.23 (17) | N3—C5—H5A | 109.6 |
O52—P5—O53 | 110.35 (18) | C6xi—C5—H5A | 109.6 |
O51—P5—H5 | 107.0 | N3—C5—H5B | 109.6 |
O52—P5—H5 | 107.0 | C6xi—C5—H5B | 109.6 |
O53—P5—H5 | 107.0 | H5A—C5—H5B | 108.1 |
O43—P4—O42 | 115.98 (18) | N3—C6—C5xi | 111.8 (3) |
O43—P4—O41 | 108.78 (17) | N3—C6—H6A | 109.3 |
O42—P4—O41 | 113.26 (17) | C5xi—C6—H6A | 109.3 |
O43—P4—H4 | 106.0 | N3—C6—H6B | 109.3 |
O42—P4—H4 | 106.0 | C5xi—C6—H6B | 109.3 |
O41—P4—H4 | 106.0 | H6A—C6—H6B | 107.9 |
O61—P6—O63 | 110.93 (18) | C8—N4—C7 | 111.3 (3) |
O61—P6—O62 | 114.00 (17) | C8—N4—H4A | 109.4 |
O63—P6—O62 | 110.48 (17) | C7—N4—H4A | 109.4 |
O61—P6—H6 | 107.0 | C8—N4—H4B | 109.3 |
O63—P6—H6 | 107.0 | C7—N4—H4B | 109.4 |
O62—P6—H6 | 107.0 | H4A—N4—H4B | 108.0 |
P1—O11—Zn5i | 133.44 (17) | N4—C7—C8v | 110.0 (4) |
P1—O12—Zn2vii | 144.69 (19) | N4—C7—H7A | 109.7 |
P1—O13—Zn1 | 134.7 (2) | C8v—C7—H7A | 109.7 |
P2—O21—Zn4 | 127.89 (17) | N4—C7—H7B | 109.7 |
P2—O22—Zn1 | 141.20 (19) | C8v—C7—H7B | 109.7 |
P2—O23—Zn2 | 129.84 (18) | H7A—C7—H7B | 108.2 |
P3—O31—Zn5vi | 137.0 (2) | N4—C8—C7v | 111.3 (4) |
P3—O32—Zn3 | 123.30 (17) | N4—C8—H8A | 109.4 |
P3—O33—Zn5 | 142.7 (2) | C7v—C8—H8A | 109.4 |
P4—O41—Zn3 | 131.28 (17) | N4—C8—H8B | 109.4 |
P4—O42—Zn4viii | 143.3 (2) | C7v—C8—H8B | 109.4 |
P4—O43—Zn4v | 139.8 (2) | H8A—C8—H8B | 108.0 |
O12—P1—O11—Zn5i | 114.4 (2) | O23—Zn2—O51—P5 | −50.6 (3) |
O13—P1—O11—Zn5i | −120.3 (2) | O12ii—Zn2—O51—P5 | −177.2 (2) |
O13—P1—O12—Zn2vii | −71.4 (4) | O53iii—Zn2—O51—P5 | 76.6 (2) |
O11—P1—O12—Zn2vii | 53.9 (4) | O51—P5—O52—Zn3 | 163.8 (2) |
O12—P1—O13—Zn1 | −155.6 (2) | O53—P5—O52—Zn3 | −69.2 (3) |
O11—P1—O13—Zn1 | 77.1 (3) | O32—Zn3—O52—P5 | −61.6 (3) |
O22—Zn1—O13—P1 | 69.6 (3) | O63—Zn3—O52—P5 | 175.9 (2) |
O61i—Zn1—O13—P1 | −52.1 (3) | O41—Zn3—O52—P5 | 61.1 (3) |
O62—Zn1—O13—P1 | −171.1 (3) | O51—P5—O53—Zn2iii | −66.5 (3) |
O22—P2—O21—Zn4 | 168.3 (2) | O52—P5—O53—Zn2iii | 167.2 (2) |
O23—P2—O21—Zn4 | 41.8 (3) | O63—P6—O61—Zn1i | −111.5 (2) |
O42iv—Zn4—O21—P2 | 158.2 (2) | O62—P6—O61—Zn1i | 14.0 (3) |
O43v—Zn4—O21—P2 | −80.9 (3) | O61—P6—O62—Zn1 | 81.1 (3) |
N1—Zn4—O21—P2 | 40.3 (3) | O63—P6—O62—Zn1 | −153.2 (2) |
O23—P2—O22—Zn1 | 105.8 (4) | O22—Zn1—O62—P6 | 137.6 (2) |
O21—P2—O22—Zn1 | −20.1 (4) | O13—Zn1—O62—P6 | 13.3 (3) |
O13—Zn1—O22—P2 | −20.8 (4) | O61i—Zn1—O62—P6 | −112.5 (2) |
O61i—Zn1—O22—P2 | 107.8 (4) | O61—P6—O63—Zn3 | −164.8 (2) |
O62—Zn1—O22—P2 | −141.0 (4) | O62—P6—O63—Zn3 | 67.8 (3) |
O22—P2—O23—Zn2 | 78.2 (3) | O52—Zn3—O63—P6 | −51.4 (3) |
O21—P2—O23—Zn2 | −154.8 (2) | O32—Zn3—O63—P6 | −171.7 (2) |
O12ii—Zn2—O23—P2 | 40.9 (3) | O41—Zn3—O63—P6 | 67.1 (2) |
O51—Zn2—O23—P2 | −85.1 (3) | O21—Zn4—N1—C1 | −42.3 (3) |
O53iii—Zn2—O23—P2 | 149.8 (2) | O42iv—Zn4—N1—C1 | −159.3 (3) |
O33—P3—O31—Zn5vi | 11.9 (4) | O43v—Zn4—N1—C1 | 80.6 (3) |
O32—P3—O31—Zn5vi | 141.2 (3) | O21—Zn4—N1—C2 | −168.5 (3) |
O31—P3—O32—Zn3 | −173.1 (2) | O42iv—Zn4—N1—C2 | 74.4 (3) |
O33—P3—O32—Zn3 | −42.5 (3) | O43v—Zn4—N1—C2 | −45.6 (3) |
O52—Zn3—O32—P3 | −58.9 (2) | C2—N1—C1—C2ix | −53.5 (5) |
O63—Zn3—O32—P3 | 63.1 (3) | Zn4—N1—C1—C2ix | 179.5 (3) |
O41—Zn3—O32—P3 | 179.6 (2) | C1—N1—C2—C1ix | 53.5 (5) |
O31—P3—O33—Zn5 | 63.6 (4) | Zn4—N1—C2—C1ix | −176.6 (3) |
O32—P3—O33—Zn5 | −63.8 (3) | O31vi—Zn5—N2—C3 | −61.3 (3) |
O31vi—Zn5—O33—P3 | −86.1 (3) | O33—Zn5—N2—C3 | 172.1 (3) |
O11i—Zn5—O33—P3 | 157.4 (3) | O11i—Zn5—N2—C3 | 53.4 (3) |
N2—Zn5—O33—P3 | 37.4 (3) | O31vi—Zn5—N2—C4 | 65.1 (3) |
O43—P4—O41—Zn3 | −177.4 (2) | O33—Zn5—N2—C4 | −61.5 (3) |
O42—P4—O41—Zn3 | 52.1 (3) | O11i—Zn5—N2—C4 | 179.8 (3) |
O52—Zn3—O41—P4 | 172.8 (2) | C4—N2—C3—C4x | 53.3 (6) |
O32—Zn3—O41—P4 | −67.0 (3) | Zn5—N2—C3—C4x | −178.4 (3) |
O63—Zn3—O41—P4 | 53.9 (3) | C3—N2—C4—C3x | −52.6 (6) |
O43—P4—O42—Zn4viii | −73.7 (4) | Zn5—N2—C4—C3x | 178.0 (3) |
O41—P4—O42—Zn4viii | 53.1 (4) | C6—N3—C5—C6xi | 54.3 (5) |
O42—P4—O43—Zn4v | 2.9 (4) | C5—N3—C6—C5xi | −55.0 (5) |
O41—P4—O43—Zn4v | −126.1 (3) | C8—N4—C7—C8v | −56.2 (5) |
O52—P5—O51—Zn2 | 98.3 (2) | C7—N4—C8—C7v | 56.9 (5) |
O53—P5—O51—Zn2 | −27.1 (3) |
Symmetry codes: (i) −x+1, −y+1, −z+1; (ii) x+1, y, z; (iii) −x+2, −y+1, −z+2; (iv) x, y+1, z; (v) −x+1, −y+1, −z+2; (vi) −x+2, −y, −z+1; (vii) x−1, y, z; (viii) x, y−1, z; (ix) −x+2, −y+2, −z+2; (x) −x+1, −y, −z+1; (xi) −x+2, −y+1, −z+1. |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1A···O32iv | 0.91 | 2.12 | 2.993 (4) | 160 |
N2—H2A···O63 | 0.91 | 2.15 | 2.967 (4) | 150 |
N3—H3A···O11i | 0.90 | 1.93 | 2.799 (4) | 163 |
N3—H3B···O62 | 0.90 | 1.96 | 2.841 (5) | 165 |
N4—H4A···O53 | 0.90 | 2.10 | 2.853 (5) | 141 |
N4—H4B···O41 | 0.90 | 1.89 | 2.772 (4) | 168 |
Symmetry codes: (i) −x+1, −y+1, −z+1; (iv) x, y+1, z. |
Experimental details
Crystal data | |
Chemical formula | (C4H12N2)[Zn5(HPO3)6(C4H10N2) |
Mr | 981.01 |
Crystal system, space group | Triclinic, P1 |
Temperature (K) | 293 |
a, b, c (Å) | 8.8634 (4), 12.6390 (6), 12.8768 (6) |
α, β, γ (°) | 89.182 (1), 89.913 (1), 86.941 (1) |
V (Å3) | 1440.31 (12) |
Z | 2 |
Radiation type | Mo Kα |
µ (mm−1) | 4.52 |
Crystal size (mm) | 0.13 × 0.07 × 0.06 |
Data collection | |
Diffractometer | Bruker SMART 1000 CCD diffractometer |
Absorption correction | Multi-scan (SADABS; Bruker, 1999) |
Tmin, Tmax | 0.583, 0.763 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 16520, 8229, 5216 |
Rint | 0.039 |
(sin θ/λ)max (Å−1) | 0.703 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.040, 0.077, 0.90 |
No. of reflections | 8229 |
No. of parameters | 370 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 1.14, −0.59 |
Computer programs: SMART (Bruker, 1999), SAINT (Bruker, 1999), SAINT, SHELXS97 (Sheldrick, 1997), SHELXL97 (Sheldrick, 1997), ORTEP-3 (Farrugia, 1997), SHELXL97.
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1A···O32i | 0.91 | 2.12 | 2.993 (4) | 160 |
N2—H2A···O63 | 0.91 | 2.15 | 2.967 (4) | 150 |
N3—H3A···O11ii | 0.90 | 1.93 | 2.799 (4) | 163 |
N3—H3B···O62 | 0.90 | 1.96 | 2.841 (5) | 165 |
N4—H4A···O53 | 0.90 | 2.10 | 2.853 (5) | 141 |
N4—H4B···O41 | 0.90 | 1.89 | 2.772 (4) | 168 |
Symmetry codes: (i) x, y+1, z; (ii) −x+1, −y+1, −z+1. |
Acknowledgements
We thank Laura Gordon for experimental assistance.
References
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© International Union of Crystallography. Prior permission is not required to reproduce short quotations, tables and figures from this article, provided the original authors and source are cited. For more information, click here.
The title compound, (I), complements the growing family of organically templated zinc–hydrogen phosphite networks (Rodgers & Harrison, 2000; Harrison, 2001; Dong et al., 2003; Lin et al., 2004).
As shown in Fig. 1, there are five distinct Zn atoms in (I). Three of these metal ions are bonded to four O-atom neighbours in tetrahdral geometry, and two (Zn4 and Zn5) are bonded to three O atoms and one N atom, the latter atom being part of a piperazine molecule. The mean Zn—O bond length [1.935 (3) Å] is typical for this family of phases (Harrison, 2001) and the Zn—N bonds (Table 1) are also characteristically longer (Kirkpatrick & Harrison, 2004) than the Zn—O links.
The six P atoms all form the centres of tetrahedral [HPO3]2− anions. Because the P—H vertex of this species does not participate in chemical bonds, the shape of this group is often described as pseudo-pyramidal. The mean P—O bond length in (I) [1.516 (3) Å] and the narrow spread of P—O distances [1.498 (3)–1.532 (3) Å] is normal (Lin et al., 2004).
The 18 O atoms in (I) all exist as Zn—O—P bridges, with a mean bond angle of 133.6° [spread of values = 123.30 (17)–144.69 (19)°], thus there are no terminal or `dangling' P═O or P—OH bonds in (I) as seen in some related phases (Harrison, 2001). There are no Zn—O—Zn or P—O—P bridges in (I).
The organic species exists in both neutral and diprotonated forms in (I). There are four distinct half molecules in the asymmetric unit (two neutral and two protonated). The four complete molecules are generated by inversion symmetry in every case and the resulting molecular conformations are typical six-ring chairs. The neutral piperazine molecules (containing atoms N1 and N2) form ligand-like bonds to Zn atoms from both their N atoms, i.e. they are acting as framework bridges (Ritchie & Harrison, 2005). The Zn atoms are in equatorial positions with respect to the six-membered ring, and the axial H atoms form N—H···O hydrogen bonds (Table 2).
The two diprotonated piperazinium ions (containing atoms N3 and N4) interact with the zincophosphite network by way of N—H···O hydrogen bonds. Each N atom makes two N—H···O bonds [mean H···O = 1.97, mean N···O = 2.816 (4) Å and mean N—H···O = 159°] and occupies a polyhedral 12 ring (Fig. 2).
The complex structure of (I) can be decomposed into several distinctive subunits. However, the description presented here certainly is not intended to imply that these subunits necessarily play a well defined step-wise role in the formation of (I) from small atomic/molecular units in solution. First, the Zn1, Zn2, Zn3, P2, P5 and P6-centred polyhedra combine to form chains of alternating polyhedral six (i.e. three ZnO4 tetrahedra + three HPO3 pseudo-pyramids) and four rings propagating in the [101] direction (Fig. 3). In turn, the P1 phosphite groups link to atoms Zn1 and Zn2 and thus crosslink the [101] chains into an infinite (010) sheet.
Considered in isolation, the Zn4- and P4-centred polyhedra and the N1-containing piperazine ring form a distinctive hybrid organic/inorganic chain propagating in [100]. The chain consists of inversion-symmetry-generated four rings (2 Zn4 + 2 P4), bridged by the piperazine molecules (Fig. 4). The Zn5 and P3 groups and the N2-containing piperazine species form a very similar chain that also propagates in the [100] direction. These two chains alternate with respect to the c direction.
When these subunits are conceptually assembled together, a complex three-dimensional framework results. There are lacunae in the hybrid organic/inorganic network that accommodate the N3 and N4-containing diprotonated piperazinium cations as described above. When viewed down [110] there appear to be channels present in the framework (Fig. 5). However, it is notable that, in every channel, the ligand-like and protonated organic species alternate; thus it is extremely unlikely that the hydrogen-bonded piperazinium species could be removed without drastic changes in the hybrid framework.
Compound (I) complements several other piperazinium zinc phosphites including C4H12N2·Zn6(HPO3)8·2H3O (Dong et al., 2003), C4H12N2·Zn3(HPO3)4 (Lin et al., 2004) and C4H12N2·Zn(HPO3)2 (Shi et al., 2004). These are more conventional templated networks in which the protonated organic speices interacts with the inorganic network by way of N—H···O bonds (Cheetham et al., 1999). Thus, as seen for other templating species, a wide variety of templated networks can arise (Kirkpatrick & Harrison, 2004) for the same combination of metal, oxo-anion and template depending on synthesis conditions. Compound (I) is particularly notable for the dual role – as a framework bridge and as a protonated template – played by the organic speices.