Tetra­aqua­(1,10-phenanthroline-κ2N,N′)magnesium(II) bis­[(2,4-dichloro­phen­yl)acetate]

Hao, X.-M.; Gu, C.-S.; Song, W.-D.; Liu, J.-W.

doi:10.1107/S1600536808022150

metal-organic compounds

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ISSN: 2056-9890

Volume 64| Part 8| August 2008| Page m1052

doi:10.1107/S1600536808022150

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Tetraaqua(1,10-phenanthroline-κ²N,N′)magnesium(II) bis[(2,4-dichlorophenyl)acetate]

Xiao-Min Hao,^a ^* Chang-Sheng Gu,^a Weng-Dong Song ^a and Ji-Wei Liu ^b

^aDepartment of Applied Chemistry, Guangdong Ocean University, Zhanjiang 524088, People's Republic of China, and ^bCollege of Chemistry and Chemical Technology, Daqing Petroleum Institute, Daqing 163318, People's Republic of China
^*Correspondence e-mail: liujiwei76@126.com

(Received 22 May 2008; accepted 15 July 2008; online 23 July 2008)

In the mononuclear title complex, [Mg(C₁₂H₈N₂)(H₂O)₄](C₈H₅Cl₂O₂)₂, each Mg^II ion is hexacoordinated by two N atoms from a 1,10-phenanthroline ligand [Mg—N = 2.233 (2) Å] and four water molecules [Mg—OW = 2.033 (2) and 2.043 (1) Å] in a distorted octahedral geometry. A twofold rotation axis passes through the Mg atom. In the crystal structure, the cations and anions are linked by intermolecular O—H⋯O hydrogen bonds and π–π stacking interactions [centroid–centroid distance = 3.804 (2) Å] into layers parallel to the ac plane.

Related literature

For related literature, see: Castellari et al. (1999 ); Kopylovich et al. (2003 ); Sharma et al. (2007 ); Zhou et al. (2007 ).

Experimental

Crystal data

[Mg(C₁₂H₈N₂)(H₂O)₄](C₈H₅Cl₂O₂)₂
M_r = 684.62
Monoclinic, C 2/c
a = 28.926 (1) Å
b = 14.0447 (6) Å
c = 7.6074 (3) Å
β = 94.785 (1)°
V = 3079.8 (2) Å³
Z = 4
Mo Kα radiation
μ = 0.46 mm⁻¹
T = 273 (2) K
0.34 × 0.26 × 0.18 mm

Data collection

Bruker P4 diffractometer
Absorption correction: empirical [OR multi-scan](using intensity measurements) (SADABS; Sheldrick, 1996 ) T_min = 0.867, T_max = 0.921
10955 measured reflections
3732 independent reflections
2619 reflections with I > 2σ(I)
R_int = 0.021

Refinement

R[F² > 2σ(F²)] = 0.042
wR(F²) = 0.117
S = 1.02
3732 reflections
207 parameters
6 restraints
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.36 e Å⁻³
Δρ_min = −0.47 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O2W—H2W1⋯O1ⁱ	0.849 (9)	1.876 (9)	2.725 (2)	178 (2)
O2W—H2W2⋯O1ⁱⁱ	0.841 (9)	1.96 (1)	2.772 (2)	161 (2)
O1W—H1W1⋯O2ⁱⁱⁱ	0.851 (9)	1.91 (1)	2.728 (2)	162 (2)
O1W—H1W2⋯O2ⁱ	0.849 (9)	1.84 (1)	2.685 (2)	171 (2)
Symmetry codes: (i) x, y, z-1; (ii) $[-x+1, y, -z+{\script{1\over 2}}]$ ; (iii) $[x, -y+1, z-{\script{1\over 2}}]$ .

Data collection: APEX2 (Bruker, 2004 ); cell refinement: SAINT (Bruker, 2004); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXL97.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536808022150/im2068sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536808022150/im2068Isup2.hkl

checkCIF report

Comment top

The rigid-type phenylacetic acid and its derivatives have versatile binding abilities and the potential capabilities of generating complicated supramolecular architectures. Nevertleless, main group or transition metal compounds in which the phenylacetate ion does not coordinate the metals are rare (Castellari et al. (1999), Kopylovich et al. (2003), Sharma et al. (2007), Zhou et al. (2007)). In the present study, we chose 2,4-dichlorophenylacetate as the anion to prepare a new mononuclear magnesium^II complex, [Mg(C₁₂H₈N₂)(H₂O)₄][(C₈H₅Cl₂O₂)₂], (I), the crystal structure of which is reported here.

As illustrated in Fig. 1, the asymmetric unit of (I) consists of one half of a [Mg(1,10-phen)(H₂O)₄] cation and one 2,4-dichlorophenylacetate anion. The Mg^II atom displays a distorted octahedral geometry defined by two N atoms from the 1,10-phenanthroline ligand [Mg—N 2.233 (2) Å] and four water molecules [Mg—Ow 2.033 (2), 2.043 (1) Å], respectively. The characteristic C—O(carboxylate) bond lengths suggest electron delocalization in the carboxylate groups of the anionic moieties. In the crystal structure, the cations and anions are linked by intermolecular O—H···O hydrogen bonds between the carboxylate O atoms and the coordinated water molecules. Additional π-π stacking interactions between 1,10-phen ligands with a distance of 3.804 (2) Å leads to the observation of layers parallel to the ac-plane (details see Table 1 and Fig. 2).

Related literature top

For related literature, see: Castellari et al. (1999); Kopylovich et al. (2003); Sharma et al. (2007); Zhou et al. (2007).

Experimental top

Benzyloxyacetic acid is commercially available and was used without further purification. The title complex was prepared by the addition of Mg(Cl)₂ × 6 H₂O (4.06 g, 20 mmol) and 1,10-phenanthroline (3.98 g, 20 mmol) to a hot aqueous solution of 2,4-dichlorophenylacetic acid (4.10 g, 20 mmol); the pH was adjusted to 6 with 0.1M sodium hydroxide. The solution was allowed to evaporate at room temperature. Colorless crystals separated from the filtered solution after several days. CHN analysis: Calcd. for C₂₈H₂₆N₂O₈Cl₄Mg: C 49.12, H 3.83, N 4.09%. Found: C 49.14, H 3.82, 4.08%.

Computing details top

Data collection: APEX2 (Bruker, 2004); cell refinement: SAINT (Bruker, 2004); data reduction: SAINT (Bruker, 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top

	Fig. 1. Molecular structure of (I) with 30% probability ellipsoids.
	Fig. 2. Packing diagram of (I).

Tetraaqua(1,10-phenanthroline-κ²N,N')magnesium(II) bis[(2,4-dichlorophenyl)acetate] top

Crystal data top

[Mg(C₁₂H₈N₂)(H₂O)₄](C₈H₅Cl₂O₂)₂	F(000) = 1408
M_r = 684.62	D_x = 1.477 Mg m⁻³
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2yc	Cell parameters from 10366 reflections
a = 28.926 (1) Å	θ = 2.8–28.2°
b = 14.0447 (6) Å	µ = 0.46 mm⁻¹
c = 7.6074 (3) Å	T = 273 K
β = 94.785 (1)°	Prism, colorless
V = 3079.8 (2) Å³	0.34 × 0.26 × 0.18 mm
Z = 4

Data collection top

Bruker P4 diffractometer	3732 independent reflections
Radiation source: fine-focus sealed tube	2619 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.021
Detector resolution: 10.000 pixels mm^-1	θ_max = 28.2°, θ_min = 2.8°
ω scans	h = −38→33
Absorption correction: empirical (using intensity measurements) (SADABS; Sheldrick, 1996)	k = −18→18
T_min = 0.867, T_max = 0.921	l = −9→10
10955 measured reflections

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.042	H atoms treated by a mixture of independent and constrained refinement
wR(F²) = 0.118	w = 1/[σ²(F_o²) + (0.0514P)² + 1.7903P] where P = (F_o² + 2F_c²)/3
S = 1.03	(Δ/σ)_max < 0.001
3732 reflections	Δρ_max = 0.36 e Å⁻³
207 parameters	Δρ_min = −0.47 e Å⁻³
6 restraints	Extinction correction: SHELXL97 (Sheldrick, 2008)
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0001 (1)

Crystal data top

[Mg(C₁₂H₈N₂)(H₂O)₄](C₈H₅Cl₂O₂)₂	V = 3079.8 (2) Å³
M_r = 684.62	Z = 4
Monoclinic, C2/c	Mo Kα radiation
a = 28.926 (1) Å	µ = 0.46 mm⁻¹
b = 14.0447 (6) Å	T = 273 K
c = 7.6074 (3) Å	0.34 × 0.26 × 0.18 mm
β = 94.785 (1)°

Data collection top

Bruker P4 diffractometer	3732 independent reflections
Absorption correction: empirical (using intensity measurements) (SADABS; Sheldrick, 1996)	2619 reflections with I > 2σ(I)
T_min = 0.867, T_max = 0.921	R_int = 0.021
10955 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.042	6 restraints
wR(F²) = 0.118	H atoms treated by a mixture of independent and constrained refinement
S = 1.03	Δρ_max = 0.36 e Å⁻³
3732 reflections	Δρ_min = −0.47 e Å⁻³
207 parameters

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
Mg1	0.5000	0.70119 (6)	0.2500	0.0377 (2)
Cl1	0.30958 (2)	0.68124 (5)	0.95908 (8)	0.06695 (19)
Cl2	0.25982 (3)	0.96821 (5)	0.52259 (13)	0.0957 (3)
O1	0.42857 (5)	0.68303 (10)	0.76580 (19)	0.0501 (3)
O1W	0.44481 (6)	0.61206 (10)	0.20734 (19)	0.0613 (4)
O2W	0.50764 (5)	0.69659 (11)	−0.01445 (17)	0.0480 (3)
O2	0.41678 (5)	0.54277 (10)	0.88709 (19)	0.0544 (4)
N1	0.45496 (5)	0.82808 (11)	0.1896 (2)	0.0423 (4)
C1	0.41135 (7)	0.82785 (17)	0.1205 (3)	0.0577 (6)
H1A	0.3966	0.7697	0.0991	0.069*
C2	0.38664 (9)	0.9115 (2)	0.0787 (4)	0.0733 (7)
H2A	0.3562	0.9084	0.0293	0.088*
C3	0.40715 (9)	0.9969 (2)	0.1101 (3)	0.0705 (7)
H3A	0.3907	1.0527	0.0846	0.085*
C4	0.45322 (8)	1.00081 (15)	0.1812 (3)	0.0552 (5)
C5	0.47614 (6)	0.91362 (12)	0.2161 (2)	0.0392 (4)
C6	0.47783 (10)	1.08762 (15)	0.2176 (4)	0.0734 (8)
H6A	0.4627	1.1453	0.1957	0.088*
C7	0.33544 (7)	0.68867 (14)	0.6254 (3)	0.0457 (5)
C8	0.31108 (6)	0.73310 (14)	0.7514 (3)	0.0456 (4)
C9	0.28790 (7)	0.81845 (15)	0.7222 (3)	0.0544 (5)
H9A	0.2720	0.8466	0.8101	0.065*
C10	0.28898 (7)	0.86044 (16)	0.5596 (3)	0.0603 (6)
C11	0.31228 (9)	0.81981 (19)	0.4301 (3)	0.0698 (7)
H11A	0.3128	0.8491	0.3206	0.084*
C12	0.33515 (8)	0.73431 (19)	0.4637 (3)	0.0628 (6)
H12A	0.3508	0.7066	0.3750	0.075*
C13	0.36083 (7)	0.59691 (15)	0.6623 (3)	0.0532 (5)
H13A	0.3682	0.5690	0.5514	0.064*
H13B	0.3406	0.5530	0.7176	0.064*
C14	0.40558 (7)	0.60887 (14)	0.7815 (2)	0.0413 (4)
H2W1	0.4831 (4)	0.6910 (16)	−0.083 (2)	0.062*
H2W2	0.5312 (4)	0.6889 (16)	−0.071 (2)	0.062*
H1W1	0.4397 (8)	0.5689 (12)	0.2818 (19)	0.062*
H1W2	0.4390 (8)	0.5895 (14)	0.1044 (13)	0.062*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Mg1	0.0472 (5)	0.0291 (4)	0.0373 (4)	0.000	0.0060 (4)	0.000
Cl1	0.0679 (4)	0.0739 (4)	0.0613 (4)	0.0017 (3)	0.0193 (3)	0.0105 (3)
Cl2	0.0834 (5)	0.0587 (4)	0.1391 (7)	0.0047 (3)	−0.0259 (5)	0.0226 (4)
O1	0.0404 (7)	0.0532 (8)	0.0568 (9)	−0.0033 (6)	0.0054 (6)	0.0051 (6)
O1W	0.0958 (12)	0.0482 (8)	0.0394 (8)	−0.0322 (8)	0.0021 (8)	0.0015 (6)
O2W	0.0441 (8)	0.0631 (9)	0.0373 (7)	0.0031 (7)	0.0062 (6)	0.0027 (6)
O2	0.0743 (10)	0.0418 (7)	0.0463 (8)	0.0029 (7)	−0.0003 (7)	−0.0041 (6)
N1	0.0421 (9)	0.0402 (8)	0.0452 (9)	0.0014 (7)	0.0074 (7)	0.0005 (7)
C1	0.0458 (12)	0.0650 (14)	0.0623 (14)	0.0013 (10)	0.0035 (10)	0.0007 (11)
C2	0.0489 (13)	0.095 (2)	0.0760 (17)	0.0240 (14)	0.0029 (11)	0.0105 (15)
C3	0.0744 (17)	0.0695 (16)	0.0687 (16)	0.0356 (14)	0.0129 (13)	0.0151 (13)
C4	0.0762 (15)	0.0408 (10)	0.0513 (12)	0.0170 (10)	0.0204 (11)	0.0065 (9)
C5	0.0504 (10)	0.0320 (8)	0.0368 (9)	0.0040 (8)	0.0137 (7)	0.0022 (7)
C6	0.114 (2)	0.0323 (10)	0.0777 (18)	0.0144 (11)	0.0287 (16)	0.0067 (11)
C7	0.0366 (10)	0.0509 (11)	0.0486 (11)	−0.0043 (8)	−0.0024 (8)	−0.0053 (9)
C8	0.0377 (10)	0.0482 (11)	0.0509 (11)	−0.0053 (8)	0.0037 (8)	0.0014 (9)
C9	0.0407 (11)	0.0514 (12)	0.0710 (15)	−0.0013 (9)	0.0041 (10)	−0.0032 (10)
C10	0.0440 (12)	0.0514 (12)	0.0827 (17)	−0.0039 (10)	−0.0108 (11)	0.0088 (12)
C11	0.0623 (15)	0.0838 (18)	0.0612 (15)	−0.0099 (13)	−0.0061 (12)	0.0236 (13)
C12	0.0558 (13)	0.0827 (17)	0.0498 (12)	−0.0009 (12)	0.0034 (10)	−0.0016 (12)
C13	0.0486 (12)	0.0500 (12)	0.0602 (13)	0.0000 (9)	−0.0006 (9)	−0.0155 (10)
C14	0.0430 (10)	0.0424 (10)	0.0395 (10)	0.0058 (8)	0.0095 (8)	−0.0086 (8)

Geometric parameters (Å, º) top

Mg1—N1	2.2327 (16)	C3—C4	1.397 (3)
Mg1—O1W	2.0333 (15)	C3—H3A	0.9300
Mg1—O2W	2.0432 (13)	C4—C5	1.407 (3)
Mg1—N1ⁱ	2.2327 (16)	C4—C6	1.427 (3)
Mg1—O1Wⁱ	2.0333 (15)	C5—C5ⁱ	1.433 (4)
Mg1—O2Wⁱ	2.0432 (13)	C6—C6ⁱ	1.335 (6)
Cl1—C8	1.744 (2)	C6—H6A	0.9300
Cl2—C10	1.744 (2)	C7—C8	1.385 (3)
N1—C1	1.325 (3)	C7—C12	1.386 (3)
N1—C5	1.356 (2)	C7—C13	1.498 (3)
O1—C14	1.247 (2)	C8—C9	1.382 (3)
O2—C14	1.252 (2)	C9—C10	1.373 (3)
O1W—H1W1	0.851 (9)	C9—H9A	0.9300
O1W—H1W2	0.849 (9)	C10—C11	1.365 (4)
O2W—H2W1	0.849 (9)	C11—C12	1.384 (3)
O2W—H2W2	0.841 (9)	C11—H11A	0.9300
C1—C2	1.399 (3)	C12—H12A	0.9300
C1—H1A	0.9300	C13—C14	1.527 (3)
C2—C3	1.350 (4)	C13—H13A	0.9700
C2—H2A	0.9300	C13—H13B	0.9700

N1ⁱ—Mg1—N1	74.07 (8)	C3—C4—C6	123.6 (2)
O1W—Mg1—N1	91.24 (6)	C4—C3—H3A	120.2
O1Wⁱ—Mg1—N1	163.97 (7)	C4—C5—C5ⁱ	119.50 (13)
O1W—Mg1—O1Wⁱ	104.01 (11)	C4—C6—H6A	119.3
O1W—Mg1—O2W	88.36 (6)	C5—N1—Mg1	115.34 (12)
O1Wⁱ—Mg1—O2W	89.41 (6)	C5—C4—C6	119.2 (2)
O2Wⁱ—Mg1—N1	96.82 (6)	C6ⁱ—C6—C4	121.32 (14)
O2W—Mg1—N1	86.08 (6)	C6ⁱ—C6—H6A	119.3
O2Wⁱ—Mg1—O2W	176.38 (9)	C7—C8—Cl1	119.45 (15)
Mg1—O1W—H1W1	120.6 (15)	C7—C12—H12A	118.9
Mg1—O1W—H1W2	118.1 (15)	C7—C13—C14	113.25 (16)
Mg1—O2W—H2W1	117.2 (14)	C7—C13—H13A	108.9
Mg1—O2W—H2W2	131.6 (14)	C7—C13—H13B	108.9
N1—C1—C2	122.7 (2)	C8—C7—C12	116.1 (2)
N1—C1—H1A	118.7	C8—C7—C13	121.84 (19)
N1—C5—C4	122.90 (18)	C8—C9—H9A	121.0
N1—C5—C5ⁱ	117.60 (10)	C9—C8—C7	123.2 (2)
O1—C14—O2	124.69 (18)	C9—C8—Cl1	117.34 (17)
O1—C14—C13	117.88 (18)	C9—C10—Cl2	118.1 (2)
O2—C14—C13	117.42 (18)	C10—C9—C8	118.0 (2)
O1W—Mg1—N1ⁱ	163.97 (7)	C10—C9—H9A	121.0
O1Wⁱ—Mg1—N1ⁱ	91.24 (6)	C10—C11—C12	119.1 (2)
O1W—Mg1—O2Wⁱ	89.41 (6)	C10—C11—H11A	120.5
O1Wⁱ—Mg1—O2Wⁱ	88.36 (6)	C11—C10—C9	121.4 (2)
O2Wⁱ—Mg1—N1ⁱ	86.08 (6)	C11—C10—Cl2	120.5 (2)
O2W—Mg1—N1ⁱ	96.82 (6)	C11—C12—C7	122.2 (2)
C1—N1—C5	117.67 (17)	C11—C12—H12A	118.9
C1—N1—Mg1	126.82 (14)	C12—C7—C13	122.1 (2)
C1—C2—H2A	120.1	C12—C11—H11A	120.5
C2—C1—H1A	118.7	C14—C13—H13A	108.9
C2—C3—C4	119.7 (2)	C14—C13—H13B	108.9
C2—C3—H3A	120.2	H1W1—O1W—H1W2	108.5 (14)
C3—C2—C1	119.8 (2)	H2W1—O2W—H2W2	110.2 (14)
C3—C2—H2A	120.1	H13A—C13—H13B	107.7
C3—C4—C5	117.2 (2)

Mg1—N1—C1—C2	−176.53 (18)	C5—N1—C1—C2	−1.5 (3)
Mg1—N1—C5—C4	178.64 (15)	C5—C4—C6—C6ⁱ	0.6 (5)
Mg1—N1—C5—C5ⁱ	−1.9 (3)	C6—C4—C5—N1	178.3 (2)
N1ⁱ—Mg1—N1—C1	175.8 (2)	C6—C4—C5—C5ⁱ	−1.2 (3)
N1ⁱ—Mg1—N1—C5	0.66 (9)	C7—C8—C9—C10	0.5 (3)
N1—C1—C2—C3	−0.6 (4)	C7—C13—C14—O1	−35.1 (3)
O1W—Mg1—N1—C1	−10.68 (18)	C7—C13—C14—O2	145.54 (19)
O1Wⁱ—Mg1—N1—C1	151.6 (2)	C8—C7—C12—C11	0.6 (3)
O1W—Mg1—N1—C5	174.14 (13)	C8—C7—C13—C14	−74.1 (2)
O1Wⁱ—Mg1—N1—C5	−23.6 (3)	C8—C9—C10—C11	−0.2 (3)
O2Wⁱ—Mg1—N1—C1	−100.24 (18)	C8—C9—C10—Cl2	−179.92 (15)
O2W—Mg1—N1—C1	77.59 (18)	C9—C10—C11—C12	0.2 (4)
O2Wⁱ—Mg1—N1—C5	84.59 (13)	C10—C11—C12—C7	−0.4 (4)
O2W—Mg1—N1—C5	−97.59 (13)	Cl1—C8—C9—C10	179.64 (16)
C1—N1—C5—C4	3.0 (3)	C12—C7—C8—C9	−0.7 (3)
C1—N1—C5—C5ⁱ	−177.5 (2)	Cl2—C10—C11—C12	179.89 (17)
C1—C2—C3—C4	1.2 (4)	C13—C7—C8—C9	179.01 (18)
C2—C3—C4—C5	0.2 (4)	C12—C7—C8—Cl1	−179.82 (15)
C2—C3—C4—C6	179.5 (2)	C12—C7—C13—C14	105.5 (2)
C3—C4—C5—N1	−2.4 (3)	C13—C7—C8—Cl1	−0.2 (3)
C3—C4—C6—C6ⁱ	−178.7 (3)	C13—C7—C12—C11	−179.0 (2)
C3—C4—C5—C5ⁱ	178.1 (2)

Symmetry code: (i) −x+1, y, −z+1/2.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O2W—H2W1···O1ⁱⁱ	0.85 (1)	1.88 (1)	2.725 (2)	178 (2)
O2W—H2W2···O1ⁱ	0.84 (1)	1.96 (1)	2.772 (2)	161 (2)
O1W—H1W1···O2ⁱⁱⁱ	0.85 (1)	1.91 (1)	2.728 (2)	162 (2)
O1W—H1W2···O2ⁱⁱ	0.85 (1)	1.84 (1)	2.685 (2)	171 (2)

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

Experimental details

Crystal data
Chemical formula	[Mg(C₁₂H₈N₂)(H₂O)₄](C₈H₅Cl₂O₂)₂
M_r	684.62
Crystal system, space group	Monoclinic, C2/c
Temperature (K)	273
a, b, c (Å)	28.926 (1), 14.0447 (6), 7.6074 (3)
β (°)	94.785 (1)
V (Å³)	3079.8 (2)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.46
Crystal size (mm)	0.34 × 0.26 × 0.18

Data collection
Diffractometer	Bruker P4 diffractometer
Absorption correction	Empirical (using intensity measurements) (SADABS; Sheldrick, 1996)
T_min, T_max	0.867, 0.921
No. of measured, independent and observed [I > 2σ(I)] reflections	10955, 3732, 2619
R_int	0.021
(sin θ/λ)_max (Å⁻¹)	0.664

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.042, 0.118, 1.03
No. of reflections	3732
No. of parameters	207
No. of restraints	6
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.36, −0.47

Computer programs: APEX2 (Bruker, 2004), SAINT (Bruker, 2004), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O2W—H2W1···O1ⁱ	0.849 (9)	1.876 (9)	2.725 (2)	178 (2)
O2W—H2W2···O1ⁱⁱ	0.841 (9)	1.96 (1)	2.772 (2)	161 (2)
O1W—H1W1···O2ⁱⁱⁱ	0.851 (9)	1.91 (1)	2.728 (2)	162 (2)
O1W—H1W2···O2ⁱ	0.849 (9)	1.84 (1)	2.685 (2)	171 (2)

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

Acknowledgements

The authors thank the Guangdong Ocean University Project (No. 0612178 and No. 0612179), the Zhanjiang City Technology Tender Project (No. 0810014) and Guangdong Ocean University for supporting this work.

References

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