Copper(II) and zinc(II) complexes of pyridine-2,6-di­carboxyl­ic acid

The title compounds, bis­(pyridine-2,6-di­carboxyl­ato-N,O,O′)copper(II) monohydrate, [Cu(C₇H₄NO₄)₂]·H₂O, andbis(pyridine-2,6-dicarboxylato-N,O,O′)zinc(II) trihydrate, [Zn(C₇H₄NO₄)₂]·3H₂O, have distorted octahedral geometries about the metal centres. Both metal ions are bonded to four O atoms and two pyridyl-N atoms from the two terdentate ligand mol­ecules, which are nearly perpendicular to each other. The copper(II) complex has twofold crystallographic symmetry and contains two different ligand mol­ecules, one of which is neutral and another doubly ionized. In contrast, the zinc(II) complex contains two identical singly ionized ligand mol­ecules. Both crystal structures are stabilized by O—H...O intermolecular hydrogen bonds between the complex and the water mol­ecules.

S1. Comment

Pyridine-2,6-dicarboxylic acid (dipicolinic acid), (I), is a compound produced by bacterial spores (Powell, 1953) which contain 5–15% of it on a dry weight basis (Church & Halvorson, 1959). It has been considered as the central component for the high heat resistance of bacterial spores, based on the hypothesis that the metal chelates of pyridine-2,6-dicarboxylic acid with divalent metal ions within the spores construct a stabilizing structure analogous to bone substance in higher animals (Chung et al., 1971). Many crystal structures of the chelate compounds of pyridine-2,6-dicarboxylic acid with divalent ions such as Ca^II (Strahs & Dickerson, 1968), Ag^II (Drew et al., 1969, 1970), Ti^II (Schwarzenbach, 1970), Sr^II (Palmer et al., 1972), Ni^II (Quaglieri et al., 1972), Fe^II (Laié et al., 1995a,b,c; Laié, Gourdon, Launay & Tuchagues, 1995) and Cu^II (Quaglieri et al., 1972) have been determined. In order to clarify the coordination modes of chelate compounds of pyridine-2,6-dicarboxylic acid with biologically important transition metal ions, we have analyzed 1:2 complexes of transition metal ions, Cu^II and Zn^II with pyridine-2,6-dicarboxylic acid (compounds (I) and (II), respectively). \sch

In (I), the complex is located on a twofold axis of symmetry which passes through C3, N1, Cu1, N2 and C7 (Fig. 1) and contains two ligands with different degrees of deprotonation, one being neutral and the other dianionic. The Cu^II ion is bonded to the nitrogen [Cu1—N1 1.914 (4) Å] and two crystallographically equivalent, negatively charged O atoms [Cu1—O2 2.019 (3) Å] of the dianionic ligand. It is also bonded, although less strongly, to the N atom [Cu1—N2 2.009 (4) Å] and two crystallographically equivalent ketonic O atoms [Cu1—O3 2.427 (3) Å] of the neutral ligand. In the (1:1) complex of Cu^II and pyridine-2,6-dicarboxylic acid (Chastain, 1965), the Cu—N distance of is 1.91 Å and that of Cu^II—O is 2.03 Å, which are comparable to the values for the doubly ionized ligand observed in this study. The bond angle of C1—C4—O2 113.2 (3)° around the carboxylato C atom of the dianionic ligand is significantly narrower than the corresponding angle C5—C8—O3 of 121.9 (4)° in the neutral ligand. These differences may depend on the electrostatic attractive force between the positively charged Cu^II ion and negatively charged O atoms of the dianionic ligand. The carboxylato groups of the dianionic ligand and the carboxyl groups of the neutral ligand lie almost in the plane of the corresponding pyridine ring as indicated by the torsion angles O2—C4—C1—N1 [0.0 (5)°] and O3—C8—C5—N2 [-6.7 (6)°].

In contrast to (I), (II) contains two identical, monoanionic ligands. The Zn^II ion is bonded to the pyridyl N atoms [Zn1—N1 2.011 (2), Zn1—N2 2.007 (2) Å], the two carboxylato O atoms [Zn1—O4 2.070 (2), Zn1—O8 2.115 (2) Å] and the two ketonic O atoms of the carboxyl groups [Zn1—O1 2.350 (2), Zn1—O5 2.321 (2) Å]. The bond angles C5—C7—O4 [115.5 (2)°] and C12—C14—O8 [115.1 (2)°] around the carboxylato C atoms are somewhat narrower than the corresponding angles around the carboxyl C atoms C1—C6—O1 [119.0 (2)°] and C8—C13—O5 [119.5 (3)°]. These differences may also depend on the electrostatic attractive force between the positively charged Zn^II ion and negatively charged O atoms of the anionic carboxylato groups as observed in the Cu^II complex. The carboxyl and carboxylato groups of the ligand molecules lie almost in the plane of the corresponding plane, as indicated by torsion angles N1—C5—C7—O3 175.1 (2), N1—C1—C6—O1 1.1 (3), N2—C8—C13—O5 3.3 (4) and N2—C12—C14—O7 - 177.8 (3)°.

The overall coordination modes about the Cu^II and Zn^II ions are similar with a distorted octahedral (trans meridional) geometry. Both metal ions are six-coordinate, and are bonded similarly to the two N and four O atoms from the two terdentate ligand molecules, which are oriented nearly perpendicular to each other. However, the copper(II) complex contains two different ligands, one neutral and one dianionic, whereas the zinc(II) complex contains two identical monoanionic ligands. This different behaviour of the ligands may be a manifestation of the Jahn-Teller effect, which is exhibited by copper(II) with its d⁹ electron configuration, but not by zinc(II) with d¹⁰.

In all of the crystal structures of 1:2 chelate complexes with transition metal ions, the ligand adopts an almost planar planar conformation, and acts as the terdentate ligand molecule in which the central metal ion is bonded to two N and four O atoms from two ligand molecules. The results of this study indicate that pyridine-2,6-dicarboxylic acid is a potential captor for transition metals in bacterial spores and its likely coordination mode in such a role. This planar conformation is also observed in the free ligand. (Takusagawa et al., 1973) is also manifested in the chelate compounds.

In the crystal structures of both (I) and (II), molecules of the metal complex are connected by O—H···O type hydrogen bonds to the uncoordinated water molecules (Tables 2 and 4). Stacking interactions between pyridine rings of the dianionic ligands are observed in the copper(II) complex, but not in the zinc(II) complex.

S2. Experimental

Compound (I): the blue crystal used for analysis was obtained by slow evaporation from a solution in ethanol:water (1:1) of a mixture containing pyridine-2,6-dicarboxylic acid and copper(II) chloride dihydrate in a 4:1 molar ratio at room temperature.

Compound(II): the colourless crystal used for analysis was obtained by the slow evaporation from a solution in ethanol:water (1:1) of a mixture containing pyridine-2,6-dicarboxylic acid and zinc(II) sulfate heptahydrate in a 4:1 molar ratio at room temperature.

S3. Refinement

The H atoms of the carboxyl groups in (I) and (II) were located from difference Fourier maps. Other H atoms were initially located from difference Fourier maps, removed and then placed in calculated positions.

The two H atoms bonded to O5 of the water molecule in (I) are not found in the Fourier maps, but are accounted for in the formula sum and formula weight calculations.

Computing details

For both compounds, data collection: MSC/AFC Diffractometer Control Software (Molecular Structure Corporation, 1992a); cell refinement: MSC/AFC Diffractometer Control Software; data reduction: TEXSAN PROCESS (Molecular Structure Corporation, 1992b); program(s) used to solve structure: SIR88 (Burla et al., 1989); program(s) used to refine structure: TEXSAN/LS (Molecular Structure Corporation, 1992); molecular graphics: ORTEPII (Johnson, 1976).

Figures

	Fig. 1. (a). ORTEPII (Johnson, 1976) drawing of (I) with the atomic numbering scheme. Ellipsoids for non-H atoms correspond to 50% probability. The symmetry code for each atom site with asterisk is (3/2 + x, y, -z).
	Fig. 2. (b). ORTEPII (Johnson, 1976) drawing of (II) with the atomic numbering scheme. Ellipsoids for non-H atoms correspond to 50% probability.

(I)

Crystal data

[Cu(C7H4NO4)2]·H2O	Dx = 1.843 Mg m^−3
Mr = 413.80	Mo Kα radiation, λ = 0.71069 Å
Orthorhombic, Pnna	Cell parameters from 25 reflections
a = 7.903 (4) Å	θ = 14.1–15.0°
b = 11.068 (4) Å	µ = 1.52 mm^−1
c = 17.053 (3) Å	T = 296 K
V = 1491 (1) Å^3	Pillar, blue
Z = 4	0.40 × 0.10 × 0.10 mm

Data collection

Rigaku AFC5R diffractometer	Rint = 0
ω–2θ scans	θmax = 27.5°
Absorption correction: ψ scan (North et al., 1968)	h = 0→9
Tmin = 0.784, Tmax = 0.859	k = 0→14
1727 measured reflections	l = 0→21
1727 independent reflections	3 standard reflections every 150 reflections
1724 reflections with I > 0.00σ(I)	intensity decay: none

Refinement

Refinement on F^2	H-atom parameters not refined
R[F^2 > 2σ(F^2)] = 0.081	w = 1/σ^2(Fo)
wR(F^2) = 0.129	(Δ/σ)max < 0.001
S = 1.03	Δρmax = 1.06 e Å^−3
1724 reflections	Δρmin = −0.75 e Å^−3
121 parameters

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

	x	y	z	Uiso*/Ueq
Cu1	0.7500	0.0000	0.31655 (3)	0.0263
O1	0.5177 (4)	0.2672 (3)	0.4344 (2)	0.0451
O2	0.6131 (4)	0.1509 (3)	0.3369 (2)	0.0360
O3	1.0058 (4)	0.1062 (3)	0.2785 (2)	0.0394
O4	1.1465 (4)	0.1373 (3)	0.1657 (2)	0.0389
O5	0.3744 (4)	0.2500	0.2500	0.0326
N1	0.7500	0.0000	0.4288 (2)	0.0246
N2	0.7500	0.0000	0.1987 (2)	0.0237
C1	0.6753 (5)	0.0911 (4)	0.4656 (2)	0.0266
C2	0.6743 (5)	0.0945 (4)	0.5470 (2)	0.0341
C3	0.7500	0.0000	0.5871 (3)	0.0398
C4	0.5947 (5)	0.1798 (4)	0.4105 (2)	0.0322
C5	0.8759 (5)	0.0510 (4)	0.1579 (2)	0.0272
C6	0.8771 (5)	0.0562 (4)	0.0765 (2)	0.0319
C7	0.7500	0.0000	0.0362 (3)	0.0340
C8	1.0157 (5)	0.1019 (4)	0.2074 (2)	0.0302
H1	0.6239	0.1670	0.5786	0.0439
H2	0.7500	0.0000	0.6432	0.0439
H3	0.9602	0.1082	0.0485	0.0439
H4	0.7500	0.0000	−0.0204	0.0439
H5	1.2395	0.1705	0.2018	0.0439

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Cu1	0.0290 (3)	0.0307 (4)	0.0192 (3)	0.0035 (4)	0.0000	0.0000
O1	0.052 (2)	0.036 (2)	0.047 (2)	0.016 (2)	−0.001 (2)	−0.009 (2)
O2	0.044 (2)	0.035 (2)	0.029 (1)	0.012 (1)	−0.003 (1)	0.000 (1)
O3	0.037 (2)	0.052 (2)	0.029 (1)	−0.016 (2)	−0.005 (1)	0.006 (1)
O4	0.031 (1)	0.051 (2)	0.035 (2)	−0.011 (1)	0.001 (1)	0.002 (1)
O5	0.021 (2)	0.043 (2)	0.034 (2)	0.0000	0.0000	0.006 (2)
N1	0.026 (2)	0.030 (2)	0.018 (2)	−0.001 (2)	0.0000	0.0000
N2	0.022 (2)	0.026 (2)	0.024 (2)	0.002 (2)	0.0000	0.0000
C1	0.024 (2)	0.028 (2)	0.028 (2)	−0.002 (2)	0.000 (2)	−0.004 (2)
C2	0.031 (2)	0.045 (3)	0.026 (2)	−0.003 (2)	0.000 (2)	−0.006 (2)
C3	0.034 (3)	0.063 (4)	0.023 (2)	−0.007 (4)	0.0000	0.0000
C4	0.027 (2)	0.036 (2)	0.034 (2)	−0.001 (2)	−0.001 (2)	−0.007 (2)
C5	0.026 (2)	0.028 (2)	0.028 (2)	0.002 (2)	0.000 (2)	−0.001 (2)
C6	0.029 (2)	0.041 (2)	0.026 (2)	0.005 (2)	0.006 (2)	0.005 (2)
C7	0.034 (3)	0.048 (3)	0.020 (2)	0.005 (3)	0.0000	0.0000
C8	0.024 (2)	0.032 (2)	0.035 (2)	−0.004 (2)	−0.004 (2)	0.005 (2)

Geometric parameters (Å, º)

Cu1—O2	2.019 (3)	N1—C1	1.327 (4)
Cu1—O3	2.427 (3)	N1—C1^i	1.327 (4)
Cu1—N1	1.914 (4)	N2—C5	1.339 (4)
Cu1—N2	2.009 (4)	N2—C5^i	1.339 (4)
Cu1—O2^i	2.019 (3)	C1—C2	1.388 (5)
Cu1—O3^i	2.427 (3)	C1—C4	1.501 (6)
O1—C4	1.213 (5)	C2—C3	1.385 (5)
O2—C4	1.303 (4)	C5—C6	1.390 (5)
O3—C8	1.216 (5)	C5—C8	1.500 (5)
O4—C8	1.314 (5)	C6—C7	1.366 (5)
O2—Cu1—O2^i	160.2 (2)	Cu1—N2—C5	121.3 (2)
O2—Cu1—O3	95.3 (1)	Cu1—N2—C5^i	121.3 (2)
O2^i—Cu1—N1	80.10 (8)	C5—N2—C5^i	117.3 (4)
O3—Cu1—N2	74.50 (7)	N1—C1—C2	119.8 (4)
O3^i—Cu1—N1	105.50 (7)	N1—C1—C4	112.9 (3)
O2—Cu1—O3^i	90.0 (1)	C2—C1—C4	127.3 (4)
O2—Cu1—N1	80.10 (8)	C1—C2—C3	118.0 (4)
O2—Cu1—N2	99.90 (8)	C2—C3—C2^i	120.9 (5)
O2^i—Cu1—O3	90.0 (1)	O1—C4—O2	125.2 (4)
O2^i—Cu1—O3^i	95.3 (1)	O1—C4—C1	121.6 (4)
O2^i—Cu1—N2	99.90 (8)	O2—C4—C1	113.2 (3)
O3—Cu1—O3^i	149.0 (1)	N2—C5—C6	122.8 (4)
O3—Cu1—N1	105.50 (7)	N2—C5—C8	114.4 (3)
O3^i—Cu1—N2	74.50 (7)	C6—C5—C8	122.8 (4)
N1—Cu1—N2	180.0000	C5—C6—C7	118.6 (4)
Cu1—O2—C4	115.4 (3)	C6—C7—C6^i	119.7 (5)
Cu1—O3—C8	107.5 (3)	O3—C8—O4	125.3 (4)
Cu1—N1—C1	118.3 (2)	O3—C8—C5	121.9 (4)
Cu1—N1—C1^i	118.3 (2)	O4—C8—C5	112.8 (3)
C1—N1—C1^i	123.5 (4)
Cu1—O2—C4—O1	179.7 (3)	O3—Cu1—O2—C4	−102.3 (3)
Cu1—O2—C4—C1	−2.0 (4)	O3^i—Cu1—O3—C8	−4.0 (3)
Cu1—O3—C8—O4	−171.8 (3)	O3—Cu1—N1—C1	90.2 (2)
Cu1—O3—C8—C5	6.7 (5)	O3—Cu1—N2—C5	0.6 (2)
Cu1—N1—C1—C2	−179.4 (3)	O3—C8—C5—N2	−6.7 (6)
Cu1—N1—C1—C4	2.2 (3)	O3—C8—C5—C6	173.4 (4)
Cu1—N2—C5—C6	−177.8 (3)	O4—C8—C5—N2	171.9 (3)
Cu1—N2—C5—C8	2.3 (4)	O4—C8—C5—C6	−8.0 (6)
O1—C4—C1—N1	178.4 (4)	N1—Cu1—O2—C4	2.5 (3)
O1—C4—C1—C2	0.2 (7)	N1—Cu1—O3—C8	176.0 (3)
O2^i—Cu1—O2—C4	2.5 (3)	N1—C1—C2—C3	−1.1 (5)
O2—Cu1—O3—C8	−102.8 (3)	N2—Cu1—O2—C4	−177.5 (3)
O2—Cu1—N1—C1	−2.6 (2)	N2—Cu1—O3—C8	−4.0 (3)
O2—Cu1—N2—C5	93.4 (2)	N2—C5—C6—C7	−4.3 (6)
O2—C4—C1—N1	0.0 (5)	C1^i—N1—C1—C2	0.6 (3)
O2—C4—C1—C2	−178.2 (4)	C1^i—N1—C1—C4	−177.8 (3)

Symmetry code: (i) −x+3/2, −y, z.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O4—H5···O5^ii	1.03	1.61	2.621 (4)	168
O5···O2			2.638 (4)

Symmetry code: (ii) x+1, y, z.

(II)

Crystal data

[Zn(C7H4NO4)2]·3H2O	Dx = 1.724 Mg m^−3
Mr = 451.65	Mo Kα radiation, λ = 0.71069 Å
Monoclinic, P21/a	Cell parameters from 25 reflections
a = 13.765 (2) Å	θ = 14.8–15.0°
b = 10.052 (2) Å	µ = 1.48 mm^−1
c = 14.060 (2) Å	T = 296 K
β = 116.554 (8)°	Pillar, colourless
V = 1740.3 (4) Å^3	0.50 × 0.15 × 0.15 mm
Z = 4

Data collection

Rigaku AFC5R diffractometer	Rint = 0.017
ω–2θ scans	θmax = 27.5°
Absorption correction: ψ scan (North et al., 1968)	h = 0→17
Tmin = 0.755, Tmax = 0.801	k = 0→13
4392 measured reflections	l = −18→16
3991 independent reflections	3 standard reflections every 150 reflections
3991 reflections with I > 0.00σ(I)	intensity decay: none

Refinement

Refinement on F^2	H-atom parameters not refined
R[F^2 > 2σ(F^2)] = 0.058	w = 1/σ^2(Fo)
wR(F^2) = 0.114	(Δ/σ)max < 0.001
S = 1.36	Δρmax = 0.81 e Å^−3
3991 reflections	Δρmin = −0.63 e Å^−3
253 parameters

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

	x	y	z	Uiso*/Ueq
Zn1	0.73609 (3)	0.00684 (3)	0.74961 (2)	0.0439
O1	0.9084 (2)	0.0566 (2)	0.7625 (2)	0.0497
O2	1.0634 (2)	0.1557 (2)	0.8743 (2)	0.0551
O3	0.6093 (2)	0.0335 (2)	0.9603 (2)	0.0524
O4	0.6263 (2)	−0.0066 (2)	0.8126 (2)	0.0492
O5	0.7837 (2)	−0.2164 (2)	0.7769 (1)	0.0492
O6	0.7773 (2)	−0.3978 (2)	0.6819 (2)	0.0574
O7	0.5726 (2)	0.2270 (3)	0.4784 (2)	0.0831
O8	0.6661 (2)	0.1733 (2)	0.6505 (2)	0.0548
O9	0.8895 (2)	0.4764 (2)	0.8470 (2)	0.0590
O10	1.1359 (2)	0.1109 (2)	0.7460 (2)	0.0691
O11	1.0102 (6)	0.0471 (7)	0.3932 (7)	0.2842
N1	0.8236 (2)	0.0860 (2)	0.8946 (2)	0.0346
N2	0.6831 (2)	−0.0739 (2)	0.6044 (2)	0.0370
C1	0.9233 (2)	0.1353 (3)	0.9266 (2)	0.0370
C2	0.9770 (2)	0.1990 (3)	1.0228 (2)	0.0445
C3	0.9255 (2)	0.2104 (3)	1.0870 (2)	0.0508
C4	0.8218 (2)	0.1592 (3)	1.0535 (2)	0.0454
C5	0.7732 (2)	0.0971 (3)	0.9556 (2)	0.0357
C6	0.9662 (2)	0.1132 (3)	0.8465 (2)	0.0401
C7	0.6597 (2)	0.0363 (3)	0.9065 (2)	0.0407
C8	0.6973 (2)	−0.2019 (3)	0.5898 (2)	0.0402
C9	0.6608 (2)	−0.2552 (4)	0.4888 (2)	0.0543
C10	0.6073 (3)	−0.1725 (4)	0.4029 (2)	0.0614
C11	0.5923 (2)	−0.0415 (4)	0.4180 (2)	0.0565
C12	0.6316 (2)	0.0071 (3)	0.5217 (2)	0.0434
C13	0.7580 (2)	−0.2749 (3)	0.6927 (2)	0.0413
C14	0.6220 (2)	0.1490 (3)	0.5509 (3)	0.0524
H1	1.0478	0.2345	1.0445	0.0534
H2	0.9612	0.2529	1.1542	0.0605
H3	0.7852	0.1668	1.0967	0.0541
H4	1.0849	0.1276	0.8118	0.0748
H5	0.6725	−0.3463	0.4790	0.0644
H6	0.5806	−0.2069	0.3328	0.0733
H7	0.5559	0.0160	0.3589	0.0678
H8	0.8210	−0.4484	0.7525	0.0748
H9	0.8730	0.4925	0.8990	0.0748
H10	0.9642	0.4709	0.8818	0.0748
H11	1.1573	0.1971	0.7223	0.0748
H12	1.1108	0.0370	0.7069	0.0748
H13	0.9851	0.0204	0.4419	0.0748
H14	0.9683	0.1086	0.3174	0.0748

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Zn1	0.0425 (2)	0.0522 (2)	0.0322 (2)	−0.0028 (1)	0.0124 (1)	−0.0055 (1)
O1	0.043 (1)	0.063 (1)	0.046 (1)	−0.0064 (10)	0.0229 (9)	−0.007 (1)
O2	0.041 (1)	0.060 (1)	0.070 (1)	−0.0106 (10)	0.029 (1)	−0.010 (1)
O3	0.047 (1)	0.069 (1)	0.049 (1)	−0.0063 (10)	0.0288 (10)	−0.003 (1)
O4	0.0386 (10)	0.067 (1)	0.040 (1)	−0.0126 (10)	0.0160 (8)	−0.0096 (9)
O5	0.054 (1)	0.050 (1)	0.034 (1)	0.0037 (9)	0.0109 (9)	0.0001 (9)
O6	0.070 (1)	0.049 (1)	0.052 (1)	0.012 (1)	0.027 (1)	−0.001 (1)
O7	0.085 (2)	0.084 (2)	0.078 (2)	0.031 (2)	0.034 (2)	0.043 (2)
O8	0.055 (1)	0.048 (1)	0.060 (1)	0.0057 (10)	0.025 (1)	0.005 (1)
O9	0.046 (1)	0.074 (2)	0.054 (1)	0.014 (1)	0.020 (1)	0.010 (1)
O10	0.077 (2)	0.059 (1)	0.097 (2)	−0.005 (1)	0.061 (1)	−0.005 (1)
O11	0.197 (6)	0.190 (5)	0.46 (1)	−0.077 (5)	0.141 (7)	−0.205 (7)
N1	0.034 (1)	0.034 (1)	0.033 (1)	−0.0006 (9)	0.0123 (8)	−0.0012 (9)
N2	0.029 (1)	0.051 (1)	0.028 (1)	0.0000 (10)	0.0110 (8)	0.0031 (10)
C1	0.033 (1)	0.032 (1)	0.040 (1)	0.000 (1)	0.011 (1)	0.001 (1)
C2	0.036 (1)	0.039 (2)	0.048 (2)	−0.004 (1)	0.010 (1)	−0.003 (1)
C3	0.054 (2)	0.051 (2)	0.039 (1)	−0.006 (1)	0.013 (1)	−0.015 (1)
C4	0.049 (2)	0.045 (2)	0.041 (1)	−0.001 (1)	0.019 (1)	−0.005 (1)
C5	0.035 (1)	0.035 (1)	0.036 (1)	0.001 (1)	0.015 (1)	0.001 (1)
C6	0.035 (1)	0.037 (1)	0.046 (2)	0.002 (1)	0.017 (1)	0.001 (1)
C7	0.036 (1)	0.043 (1)	0.041 (1)	0.000 (1)	0.016 (1)	0.001 (1)
C8	0.032 (1)	0.053 (2)	0.035 (1)	−0.003 (1)	0.015 (1)	−0.005 (1)
C9	0.048 (2)	0.071 (2)	0.042 (2)	−0.003 (2)	0.020 (1)	−0.012 (1)
C10	0.055 (2)	0.094 (3)	0.034 (2)	−0.006 (2)	0.018 (1)	−0.014 (2)
C11	0.036 (1)	0.098 (3)	0.031 (1)	0.000 (2)	0.011 (1)	0.014 (2)
C12	0.029 (1)	0.065 (2)	0.035 (1)	0.003 (1)	0.014 (1)	0.012 (1)
C13	0.034 (1)	0.049 (2)	0.041 (1)	0.002 (1)	0.016 (1)	0.001 (1)
C14	0.038 (2)	0.066 (2)	0.054 (2)	0.010 (1)	0.022 (1)	0.021 (2)

Geometric parameters (Å, º)

Zn1—O1	2.350 (2)	N1—C5	1.327 (3)
Zn1—O4	2.070 (2)	N2—C8	1.331 (4)
Zn1—O5	2.321 (2)	N2—C12	1.334 (3)
Zn1—O8	2.115 (2)	C1—C2	1.376 (4)
Zn1—N1	2.011 (2)	C1—C6	1.504 (4)
Zn1—N2	2.007 (2)	C2—C3	1.379 (4)
O1—C6	1.230 (3)	C3—C4	1.387 (4)
O2—C6	1.287 (3)	C4—C5	1.381 (4)
O3—C7	1.235 (3)	C5—C7	1.525 (4)
O4—C7	1.264 (3)	C8—C9	1.385 (4)
O5—C13	1.224 (3)	C8—C13	1.499 (4)
O6—C13	1.286 (3)	C9—C10	1.378 (5)
O7—C14	1.223 (4)	C10—C11	1.365 (5)
O8—C14	1.277 (4)	C11—C12	1.397 (4)
N1—C1	1.334 (3)	C12—C14	1.506 (4)
O1—Zn1—O4	152.33 (8)	C1—C2—C3	118.3 (2)
O1—Zn1—O5	89.54 (8)	C2—C3—C4	120.0 (3)
O1—Zn1—O8	91.69 (8)	C3—C4—C5	118.2 (3)
O1—Zn1—N1	73.21 (8)	N1—C5—C4	121.4 (2)
O1—Zn1—N2	93.44 (8)	N1—C5—C7	113.5 (2)
O4—Zn1—O5	94.18 (8)	C4—C5—C7	125.0 (2)
O4—Zn1—O8	97.39 (8)	O1—C6—O2	125.7 (3)
O4—Zn1—N1	79.22 (8)	O1—C6—C1	119.0 (2)
O4—Zn1—N2	113.95 (8)	O2—C6—C1	115.3 (2)
O5—Zn1—O8	152.37 (8)	O3—C7—O4	126.1 (3)
O5—Zn1—N1	102.60 (8)	O3—C7—C5	118.3 (2)
O5—Zn1—N2	74.01 (8)	O4—C7—C5	115.5 (2)
O8—Zn1—N1	104.18 (8)	N2—C8—C9	121.4 (3)
O8—Zn1—N2	78.36 (9)	N2—C8—C13	112.5 (2)
N1—Zn1—N2	166.39 (8)	C9—C8—C13	126.1 (3)
Zn1—O1—C6	111.8 (2)	C8—C9—C10	118.2 (3)
Zn1—O4—C7	115.5 (2)	C9—C10—C11	120.3 (3)
Zn1—O5—C13	111.5 (2)	C10—C11—C12	119.0 (3)
Zn1—O8—C14	115.1 (2)	N2—C12—C11	120.2 (3)
Zn1—N1—C1	123.2 (2)	N2—C12—C14	114.7 (2)
Zn1—N1—C5	116.0 (2)	C11—C12—C14	125.1 (3)
C1—N1—C5	120.5 (2)	O5—C13—O6	126.1 (3)
Zn1—N2—C8	122.4 (2)	O5—C13—C8	119.5 (3)
Zn1—N2—C12	116.7 (2)	O6—C13—C8	114.3 (2)
C8—N2—C12	120.9 (2)	O7—C14—O8	127.3 (3)
N1—C1—C2	121.6 (2)	O7—C14—C12	117.6 (3)
N1—C1—C6	112.5 (2)	O8—C14—C12	115.1 (2)
C2—C1—C6	125.9 (2)
Zn1—O1—C6—O2	−177.9 (2)	O1—C6—C1—N1	1.1 (3)
O2—C6—C1—C2	2.0 (4)	O7—C14—C12—N2	−177.8 (3)
Zn1—O1—C6—C1	2.8 (3)	O1—C6—C1—C2	−178.7 (3)
O3—C7—C5—N1	175.1 (2)	O7—C14—C12—C11	2.8 (4)
Zn1—O4—C7—O3	−177.3 (2)	O2—C6—C1—N1	−178.3 (2)
O3—C7—C5—C4	−5.2 (4)	O8—Zn1—O1—C6	100.2 (2)
Zn1—O4—C7—C5	2.9 (3)	O8—Zn1—O4—C7	−103.5 (2)
O4—Zn1—O1—C6	−9.3 (3)	C1—C2—C3—C4	−0.5 (4)
Zn1—O5—C13—O6	177.2 (2)	O8—Zn1—O5—C13	1.2 (3)
O4—Zn1—O5—C13	115.9 (2)	C2—C1—N1—C5	−0.1 (4)
Zn1—O5—C13—C8	−3.5 (3)	O8—Zn1—N1—C1	−82.3 (2)
O4—Zn1—O8—C14	−111.0 (2)	C2—C3—C4—C5	0.3 (5)
Zn1—O8—C14—O7	176.7 (3)	O8—Zn1—N1—C5	92.3 (2)
O4—Zn1—N1—C1	−177.2 (2)	C3—C2—C1—C6	−179.9 (3)
Zn1—O8—C14—C12	−2.3 (3)	O8—Zn1—N2—C8	179.2 (2)
O4—Zn1—N1—C5	−2.7 (2)	C3—C4—C5—C7	−179.6 (3)
Zn1—N1—C1—C2	174.3 (2)	O8—Zn1—N2—C12	−1.2 (2)
O4—Zn1—N2—C8	−87.8 (2)	C5—N1—C1—C6	−179.8 (2)
Zn1—N1—C1—C6	−5.5 (3)	O8—C14—C12—N2	1.3 (4)
O4—Zn1—N2—C12	91.7 (2)	C8—N2—C12—C11	−0.5 (4)
Zn1—N1—C5—C4	−174.9 (2)	O8—C14—C12—C11	−178.1 (3)
O4—C7—C5—N1	−5.1 (3)	C8—N2—C12—C14	−179.9 (2)
Zn1—N1—C5—C7	4.8 (3)	N1—Zn1—O1—C6	−4.1 (2)
O4—C7—C5—C4	174.5 (3)	C8—C9—C10—C11	0.8 (5)
Zn1—N2—C8—C9	−179.4 (2)	N1—Zn1—O4—C7	−0.4 (2)
O5—Zn1—O1—C6	−107.4 (2)	C9—C8—N2—C12	1.0 (4)
Zn1—N2—C8—C13	−1.1 (3)	N1—Zn1—O5—C13	−164.2 (2)
O5—Zn1—O4—C7	101.7 (2)	C9—C10—C11—C12	−0.3 (5)
Zn1—N2—C12—C11	179.9 (2)	N1—Zn1—O8—C14	168.3 (2)
O5—Zn1—O8—C14	2.9 (3)	C10—C9—C8—C13	−179.2 (3)
Zn1—N2—C12—C14	0.5 (3)	N1—Zn1—N2—C8	76.9 (4)
O5—Zn1—N1—C1	90.8 (2)	C10—C11—C12—C14	179.5 (3)
O1—Zn1—O4—C7	4.7 (3)	N1—Zn1—N2—C12	−103.5 (4)
O5—Zn1—N1—C5	−94.6 (2)	C12—N2—C8—C13	179.3 (2)
O1—Zn1—O5—C13	−91.6 (2)	N1—C1—C2—C3	0.4 (4)
O5—Zn1—N2—C8	−0.4 (2)	N1—C5—C4—C3	0.1 (4)
O1—Zn1—O8—C14	95.2 (2)	N2—Zn1—O1—C6	178.6 (2)
O5—Zn1—N2—C12	179.2 (2)	N2—Zn1—O4—C7	176.0 (2)
O1—Zn1—N1—C1	5.2 (2)	N2—Zn1—O5—C13	2.2 (2)
O5—C13—C8—N2	3.3 (4)	N2—Zn1—O8—C14	2.0 (2)
O1—Zn1—N1—C5	179.8 (2)	N2—Zn1—N1—C1	16.9 (5)
O5—C13—C8—C9	−178.5 (3)	N2—Zn1—N1—C5	−168.5 (3)
O1—Zn1—N2—C8	88.1 (2)	N2—C8—C9—C10	−1.1 (4)
O6—C13—C8—N2	−177.3 (2)	N2—C12—C11—C10	0.2 (4)
O1—Zn1—N2—C12	−92.3 (2)	C1—N1—C5—C4	−0.2 (4)
O6—C13—C8—C9	0.9 (4)	C1—N1—C5—C7	179.5 (2)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O2—H4···O10	1.08	1.40	2.462 (4)	166
O6—H8···O9^i	1.03	1.45	2.483 (2)	174
O9—H9···O3^ii	0.87	1.93	2.762 (3)	160
O9—H10···O3^iii	0.92	1.80	2.719 (3)	175
O10—H11···O8^iii	1.02	1.69	2.679 (3)	164
O10—H12···O11^iv	0.90	1.84	2.623 (6)	145
O11—H13···O11^iv	0.93	2.39	3.28 (2)	159

Symmetry codes: (i) x, y−1, z; (ii) −x+3/2, y+1/2, −z+2; (iii) x+1/2, −y+1/2, z; (iv) −x+2, −y, −z+1.