metal-organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 64| Part 7| July 2008| Pages m865-m866

catena-Poly[[[di­aqua­nickel(II)]-di-μ-glycine] dichloride]

aSchool of Chemical Science, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia, bDepartment of Chemistry, Faculty of Science, Prince of Songkla University, Hat-Yai, Songkhla 90112, Thailand, and cX-ray Crystallography Unit, School of Physics, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia
*Correspondence e-mail: hkfun@usm.my

(Received 22 May 2008; accepted 27 May 2008; online 7 June 2008)

In the polymeric title complex, {[Ni(C2H5NO2)2(H2O)2]Cl2}n, the NiII atom lies on an inversion center and is in a distorted octa­hedral NiO6 configuration, with four carboxyl­ate O atoms from four zwitterionic glycine mol­ecules forming the equatorial plane and two water O atoms occupying the axial positions. The Cl counterions lie in the inter­stices. The NiII complexes are linked into polymeric sheets parallel to the bc plane. These sheets are then further connected into a three-dimensional network by O—H⋯O, O—H⋯Cl and N—H⋯Cl hydrogen bonds, together with weak C—H⋯O inter­actions.

Related literature

For values of bond lengths and angles, see: Allen et al. (1987[Allen, F. H., Kennard, O., Watson, D. G., Brammer, L., Orpen, A. G. & Taylor, R. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1-19.]); Shannon (1976[Shannon, R. D. (1976). Acta Cryst. A32, 751-767.]). For related structures, see, for example: Fleck & Bohatý (2005[Fleck, M. & Bohatý, L. (2005). Acta Cryst. C61, m412-m416.]). For background to the application of nickel complexes, see, for example: Ferrari et al. (2002[Ferrari, M. B., Bisceglie, F., Pelosi, G., Sassi, M., Tarasconi, P., Cornia, M., Capacchi, S., Albertini, R. & Pinelli, S. (2002). J. Inorg. Biochem. 90, 113-126.]); Kasuga et al. (2001[Kasuga, N. C., Sekino, K., Koumo, C., Shimada, N., Ishikawa, M. & Nomiya, K. (2001). J. Inorg. Biochem. 98, 55-65.]); Lancaster (1998[Lancaster, J. P. (1998). Editor. The Bioinorganic Chemistry of Nickel. New York: VCH.]); Matkar et al. (2006[Matkar, S. S., Wrischnik, L. A., Jones, P. R. & Blumberg, U. H. (2006). Biochem. Biophys. Res. Commun. 343, 754-761.]); Liang et al. (2004[Liang, F., Wang, P., Zhou, X., Li, T., Li, Z.-Y., Lin, H.-K., Gao, D.-Z., Zheng, C.-Y. & Wu, C.-T. (2004). Bioorg. Med. Chem. Lett. 14, 1901-1904.]).

[Scheme 1]

Experimental

Crystal data
  • [Ni(C2H5NO2)2(H2O)2]Cl2

  • Mr = 315.76

  • Monoclinic, P 21 /c

  • a = 10.6006 (1) Å

  • b = 5.8579 (1) Å

  • c = 8.7113 (1) Å

  • β = 90.489 (1)°

  • V = 540.93 (1) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 2.30 mm−1

  • T = 100.0 (1) K

  • 0.32 × 0.22 × 0.12 mm

Data collection
  • Bruker SMART APEX2 CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2005[Bruker (2005). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.530, Tmax = 0.775

  • 11049 measured reflections

  • 2372 independent reflections

  • 2079 reflections with I > 2σ(I)

  • Rint = 0.032

Refinement
  • R[F2 > 2σ(F2)] = 0.023

  • wR(F2) = 0.056

  • S = 1.06

  • 2372 reflections

  • 98 parameters

  • All H-atom parameters refined

  • Δρmax = 0.49 e Å−3

  • Δρmin = −0.68 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N1—H1N1⋯Cl1i 0.886 (18) 2.326 (17) 3.2021 (9) 170.2 (15)
N1—H2N1⋯Cl1 0.893 (17) 2.404 (17) 3.2673 (11) 162.7 (14)
N1—H3N1⋯Cl1ii 0.884 (18) 2.446 (18) 3.2442 (11) 150.4 (15)
O1W—H1W1⋯O2iii 0.840 (18) 2.00 (2) 2.7276 (11) 145 (2)
O1W—H2W1⋯Cl1 0.81 (2) 2.34 (2) 3.1468 (9) 172.8 (17)
C2—H2B⋯O1iv 0.938 (17) 2.472 (17) 2.9549 (13) 112.0 (13)
Symmetry codes: (i) [-x+1, y+{\script{1\over 2}}, -z-{\script{1\over 2}}]; (ii) x, y+1, z; (iii) -x, -y, -z; (iv) [x, -y+{\script{1\over 2}}, z-{\script{1\over 2}}].

Data collection: APEX2 (Bruker, 2005[Bruker (2005). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: APEX2; data reduction: SAINT (Bruker, 2005[Bruker (2005). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); program(s) used to solve structure: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2003[Spek, A. L. (2003). J. Appl. Cryst. 36, 7-13.]).

Supporting information


Comment top

Nickel plays versatile and sometimes controversial roles in living systems as the biological effects of nickel are closely related to their chemical nature (Lancaster, 1998). Nickel complexes have been the subject of intense study in recent years mostly due to their biological significance such as antitumor and antibacterial activities (Matkar et al., 2006, Kasuga et al., 2001). Several nickel complexes have been found to inhibit proliferation of diverse cancer cells (Ferrari et al., 2002; Liang et al., 2004, Matkar et al., 2006). Based on the significant biological role played by nickel complexes, we have synthesized several nickel complexes and herein, we report the preparation and crystal structure of the title complex which is isomorphous with catena-poly[[[diaquanickel(II)]-di-µ- glycine] dibromide] (Fleck & Bohatý, 2005).

In the molecular structure of the polymeric title complex, {[Ni(C2H5NO2)2(H2O)2]Cl2}n (Fig. 1), the NiII lies on an inversion center and has an NiO6 coordination environment. The coordination sphere of the NiII ion is a slightly distorted octahedron consisting of the O4 coordination plane of the four glycine zwitterions (coordinating through one carboxylic O atom from each glycine zwitterion) and the two axially bound water molecules. The Ni—O(glycine) distances [Ni1—O1 = 2.0398 (7) Å and Ni1—O2 = 2.0753 (7) Å] and Ni—O(water) distances [2.0413 (8) Å] are quite similar to those observed in another closely related NiII complex which are in the range 2.033 (2)–2.086 (2) Å (Fleck & Bohatý, 2005) and are also similar to the Ni—O distances observed in ionic compounds (Shannon, 1976). Other bond lengths and angles observed in the structure are also normal (Allen et al., 1987). In the glycine zwitterion, the carboxylate group is slightly twisted from the C1/C2/N1 plane with torsion angles O2—C1—C2—N1 = 167.23 (9)° and O1—C1—C2—N1 - 14.75 (14)°. The C—O distances [C1—O1 = 1.2601 (12) Å and C1—O2 = 1.2524 (12) Å] show some electron delocalization over the carboxylate group. The Cl- ions lie in the interstices between the glycine zwitterions.

The crystal packing in Fig. 2 has shown the polymeric structure of the title polymeric complex. The NiII complex molecules are linked by O—H···O (Table 1) into polymeric sheets along the [010] direction (Fig. 3). These sheets are furthered connect to the interstial Cl- ions by O—H···Cl and N—H···Cl hydrogen bonds to the water molecules and amino groups, respectively forming a three-dimensional network (Table 1). The crystal is stabilized by O—H···O, O—H···Cl and N—H···Cl hydrogen bonds, together with weak C—H···Cl interactions (Table 1).

Related literature top

For values of bond lengths and angles, see Allen et al. (1987); Shannon (1976). For related structures, see, for example, Fleck & Bohatý (2005). For background to the application of nickel complexes, see, for example, Ferrari et al. (2002); Kasuga et al. (2001); Lancaster (1998); Matkar et al. (2006); Liang et al. (2004).

Experimental top

The title complex was synthesized by heating under reflux a 1:2 molar mixture of nickel(II) chloride hexahydrate, NiCl2.6H2O (0.2377 g, 1 mmol) and glycine (0.1503 g, 2 mmol) in water (30 ml) for 3 h. A green transparent solution was obtained and allowed to cool to room temperature. Green single crystals of the title complex suitable for X-ray structure determination were obtained after a few days of evaporation. Mp. 442–443 K.

Refinement top

H atoms were located in difference maps and refined isotropically. The highest residual electron density peak is located at 1.74 Å from O1W and the deepest hole is located at 0.72 Å from Ni1.

Computing details top

Data collection: APEX2 (Bruker, 2005); cell refinement: APEX2 (Bruker, 2005); data reduction: SAINT (Bruker, 2005); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2003).

Figures top
[Figure 1] Fig. 1. The structure of (I), showing 50% probability displacement ellipsoids and the atomic numbering. Symmetry codes for the (A) -x, -1/2 + y, -1/2 - z, (B) -x, 1/2 + y, -1/2 - z and (C) -x, -y, -z.
[Figure 2] Fig. 2. The crystal packing of (I), viewed along the a axis showing the polymeric structure. Hydrogen bonds are drawn as dashed lines.
[Figure 3] Fig. 3. The crystal packing of (I), viewed along the c axis showing the sheets running along the [010] direction. Hydrogen bonds are drawn as dashed lines.
catena-Poly[[[diaquanickel(II)]-di-µ-glycine] dichloride] top
Crystal data top
[Ni(C2H5NO2)2(H2O)2]Cl2F(000) = 324
Mr = 315.76Dx = 1.939 Mg m3
Monoclinic, P21/cMelting point = 442–443 K
Hall symbol: -P 2ybcMo Kα radiation, λ = 0.71073 Å
a = 10.6006 (1) ÅCell parameters from 2372 reflections
b = 5.8579 (1) Åθ = 3.8–34.9°
c = 8.7113 (1) ŵ = 2.30 mm1
β = 90.489 (1)°T = 100 K
V = 540.93 (1) Å3Block, green
Z = 20.32 × 0.22 × 0.12 mm
Data collection top
Bruker SMART APEX2 CCD area-detector
diffractometer
2372 independent reflections
Radiation source: fine-focus sealed tube2079 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.032
Detector resolution: 8.33 pixels mm-1θmax = 35.0°, θmin = 3.8°
ω scansh = 1717
Absorption correction: multi-scan
(SADABS; Bruker, 2005)
k = 89
Tmin = 0.530, Tmax = 0.775l = 1414
11049 measured reflections
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.023Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.056All H-atom parameters refined
S = 1.06 w = 1/[σ2(Fo2) + (0.0259P)2 + 0.1363P]
where P = (Fo2 + 2Fc2)/3
2372 reflections(Δ/σ)max = 0.001
98 parametersΔρmax = 0.49 e Å3
0 restraintsΔρmin = 0.68 e Å3
Crystal data top
[Ni(C2H5NO2)2(H2O)2]Cl2V = 540.93 (1) Å3
Mr = 315.76Z = 2
Monoclinic, P21/cMo Kα radiation
a = 10.6006 (1) ŵ = 2.30 mm1
b = 5.8579 (1) ÅT = 100 K
c = 8.7113 (1) Å0.32 × 0.22 × 0.12 mm
β = 90.489 (1)°
Data collection top
Bruker SMART APEX2 CCD area-detector
diffractometer
2372 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2005)
2079 reflections with I > 2σ(I)
Tmin = 0.530, Tmax = 0.775Rint = 0.032
11049 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0230 restraints
wR(F2) = 0.056All H-atom parameters refined
S = 1.06Δρmax = 0.49 e Å3
2372 reflectionsΔρmin = 0.68 e Å3
98 parameters
Special details top

Experimental. The low-temperature data was collected with the Oxford Cyrosystem Cobra low-temperature attachment.

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 (Å2) top
xyzUiso*/Ueq
Ni10.00000.00000.00000.00637 (5)
Cl10.38948 (2)0.28198 (5)0.05133 (3)0.01159 (6)
O10.14915 (7)0.13388 (13)0.11588 (8)0.00907 (13)
O20.04973 (7)0.34293 (14)0.29470 (8)0.01009 (14)
N10.37953 (8)0.22021 (18)0.21419 (11)0.00996 (16)
C10.14619 (9)0.25515 (18)0.23533 (11)0.00790 (16)
C20.27217 (9)0.2880 (2)0.31479 (12)0.01036 (18)
O1W0.10514 (8)0.28293 (15)0.04954 (9)0.01166 (15)
H2A0.2839 (16)0.444 (3)0.345 (2)0.017 (4)*
H2B0.2718 (16)0.195 (3)0.4024 (19)0.018 (4)*
H1N10.4466 (17)0.204 (3)0.2731 (19)0.020 (4)*
H2N10.3641 (15)0.088 (3)0.1668 (19)0.015 (4)*
H3N10.3947 (17)0.323 (3)0.142 (2)0.025 (5)*
H1W10.087 (2)0.324 (4)0.139 (2)0.038 (6)*
H2W10.180 (2)0.284 (3)0.032 (2)0.032 (5)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Ni10.00560 (8)0.00757 (9)0.00594 (8)0.00004 (6)0.00067 (5)0.00022 (6)
Cl10.00941 (10)0.01139 (12)0.01402 (11)0.00140 (8)0.00280 (8)0.00077 (8)
O10.0083 (3)0.0107 (4)0.0082 (3)0.0006 (3)0.0007 (2)0.0023 (2)
O20.0085 (3)0.0132 (4)0.0086 (3)0.0018 (3)0.0000 (2)0.0022 (3)
N10.0075 (3)0.0121 (4)0.0103 (4)0.0001 (3)0.0009 (3)0.0021 (3)
C10.0079 (4)0.0085 (4)0.0074 (4)0.0009 (3)0.0011 (3)0.0007 (3)
C20.0071 (4)0.0145 (5)0.0095 (4)0.0000 (3)0.0007 (3)0.0033 (3)
O1W0.0089 (3)0.0129 (4)0.0133 (3)0.0023 (3)0.0028 (3)0.0027 (3)
Geometric parameters (Å, º) top
Ni1—O1i2.0398 (7)N1—C21.4845 (14)
Ni1—O12.0399 (7)N1—H1N10.885 (18)
Ni1—O1Wi2.0413 (8)N1—H2N10.893 (18)
Ni1—O1W2.0414 (8)N1—H3N10.884 (19)
Ni1—O2ii2.0753 (7)C1—C21.5217 (14)
Ni1—O2iii2.0753 (7)C2—H2A0.959 (18)
O1—C11.2601 (12)C2—H2B0.939 (17)
O2—C11.2524 (12)O1W—H1W10.84 (2)
O2—Ni1iv2.0753 (7)O1W—H2W10.81 (2)
O1i—Ni1—O1180.0C2—N1—H2N1111.2 (11)
O1i—Ni1—O1Wi89.58 (3)H1N1—N1—H2N1109.0 (15)
O1—Ni1—O1Wi90.42 (3)C2—N1—H3N1111.7 (12)
O1i—Ni1—O1W90.42 (3)H1N1—N1—H3N1110.1 (16)
O1—Ni1—O1W89.58 (3)H2N1—N1—H3N1107.3 (16)
O1Wi—Ni1—O1W180.0O2—C1—O1125.94 (9)
O1i—Ni1—O2ii86.34 (3)O2—C1—C2118.48 (9)
O1—Ni1—O2ii93.66 (3)O1—C1—C2115.54 (9)
O1Wi—Ni1—O2ii87.50 (3)N1—C2—C1111.66 (8)
O1W—Ni1—O2ii92.50 (3)N1—C2—H2A108.4 (10)
O1i—Ni1—O2iii93.66 (3)C1—C2—H2A111.2 (10)
O1—Ni1—O2iii86.34 (3)N1—C2—H2B108.8 (10)
O1Wi—Ni1—O2iii92.50 (3)C1—C2—H2B107.4 (10)
O1W—Ni1—O2iii87.50 (3)H2A—C2—H2B109.4 (14)
O2ii—Ni1—O2iii180.0Ni1—O1W—H1W1107.7 (15)
C1—O1—Ni1127.70 (7)Ni1—O1W—H2W1120.0 (14)
C1—O2—Ni1iv137.59 (7)H1W1—O1W—H2W1114 (2)
C2—N1—H1N1107.6 (11)
O1Wi—Ni1—O1—C135.21 (9)Ni1iv—O2—C1—C210.54 (16)
O1W—Ni1—O1—C1144.79 (9)Ni1—O1—C1—O210.33 (16)
O2ii—Ni1—O1—C1122.74 (9)Ni1—O1—C1—C2167.51 (7)
O2iii—Ni1—O1—C157.26 (9)O2—C1—C2—N1167.23 (9)
Ni1iv—O2—C1—O1167.25 (8)O1—C1—C2—N114.75 (14)
Symmetry codes: (i) x, y, z; (ii) x, y+1/2, z+1/2; (iii) x, y1/2, z1/2; (iv) x, y+1/2, z1/2.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1N1···Cl1v0.886 (18)2.326 (17)3.2021 (9)170.2 (15)
N1—H2N1···Cl10.893 (17)2.404 (17)3.2673 (11)162.7 (14)
N1—H3N1···Cl1vi0.884 (18)2.446 (18)3.2442 (11)150.4 (15)
O1W—H1W1···O2i0.840 (18)2.00 (2)2.7276 (11)145 (2)
O1W—H2W1···Cl10.81 (2)2.34 (2)3.1468 (9)172.8 (17)
C2—H2B···O1vii0.938 (17)2.472 (17)2.9549 (13)112.0 (13)
Symmetry codes: (i) x, y, z; (v) x+1, y+1/2, z1/2; (vi) x, y+1, z; (vii) x, y+1/2, z1/2.

Experimental details

Crystal data
Chemical formula[Ni(C2H5NO2)2(H2O)2]Cl2
Mr315.76
Crystal system, space groupMonoclinic, P21/c
Temperature (K)100
a, b, c (Å)10.6006 (1), 5.8579 (1), 8.7113 (1)
β (°) 90.489 (1)
V3)540.93 (1)
Z2
Radiation typeMo Kα
µ (mm1)2.30
Crystal size (mm)0.32 × 0.22 × 0.12
Data collection
DiffractometerBruker SMART APEX2 CCD area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2005)
Tmin, Tmax0.530, 0.775
No. of measured, independent and
observed [I > 2σ(I)] reflections
11049, 2372, 2079
Rint0.032
(sin θ/λ)max1)0.806
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.023, 0.056, 1.06
No. of reflections2372
No. of parameters98
H-atom treatmentAll H-atom parameters refined
Δρmax, Δρmin (e Å3)0.49, 0.68

Computer programs: APEX2 (Bruker, 2005), SAINT (Bruker, 2005), SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2003).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1N1···Cl1i0.886 (18)2.326 (17)3.2021 (9)170.2 (15)
N1—H2N1···Cl10.893 (17)2.404 (17)3.2673 (11)162.7 (14)
N1—H3N1···Cl1ii0.884 (18)2.446 (18)3.2442 (11)150.4 (15)
O1W—H1W1···O2iii0.840 (18)2.00 (2)2.7276 (11)145 (2)
O1W—H2W1···Cl10.81 (2)2.34 (2)3.1468 (9)172.8 (17)
C2—H2B···O1iv0.938 (17)2.472 (17)2.9549 (13)112.0 (13)
Symmetry codes: (i) x+1, y+1/2, z1/2; (ii) x, y+1, z; (iii) x, y, z; (iv) x, y+1/2, z1/2.
 

Footnotes

Additional correspondence author, e-mail: suchada.c@psu.ac.th.

Acknowledgements

The authors are grateful for a SAGA Grant from the Academy of Science, Malaysia, and an FRGS Grant from the Ministry of Higher Education (MOHE), Malaysia, for funding this research. The authors also thank the Universiti Sains Malaysia for a Research University Golden Goose Grant (No. 1001/PFIZIK/811012).

References

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Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 64| Part 7| July 2008| Pages m865-m866
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