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

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{4,4′-Dimeth­­oxy-2,2′-[2,2-di­methyl­propane-1,3-diylbis(nitrilo­methanylyl­­idene)]diphenolato}copper(II) monohydrate

aDepartment of Chemistry, Payame Noor University, PO Box 19395-3697 Tehran, I. R. of IRAN, bDepartment of Chemistry, Science and Research Branch, Islamic Azad University, Tehran, Iran, cDepartment of Chemistry, University of Isfahan, 81746-73441, Isfahan, Iran, and dDepartment of Physics, University of Sargodha, Punjab, Pakistan
*Correspondence e-mail: zsrkk@yahoo.com, dmntahir_uos@yahoo.com

(Received 20 July 2012; accepted 5 September 2012; online 12 September 2012)

The asymmetric unit of the title compound, [Cu(C21H24N2O4)]·H2O, comprises half of a Schiff base complex and a water mol­ecule. The CuII atom, water mol­ecule and one C atom of the central propyl­ene segment are located on a twofold rotation axis. The geometry around the CuII atom is distorted square-planar, supported by the N2O2 donor atoms of the coordinating ligand. The dihedral angle between the symmetry-related benzene rings is 42.56 (19)°. In the crystal, O—H⋯O hydrogen bonds involving the water mol­ecule make an R21(6) ring motif. Complex mol­ecules are linked into a chain along the c axis via C—H⋯O inter­actions.

Related literature

For standard bond lengths, 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.]). For hydrogen-bond motifs, see: Bernstein et al. (1995[Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555-1573.]). For applications of Schiff bases in coordination chemistry, see, for example: Granovski et al. (1993[Granovski, A. D., Nivorozhkin, A. L. & Minkin, V. I. (1993). Coord. Chem. Rev. 126, 1-69.]); Blower et al. (1998[Blower, P. J. (1998). Transition Met. Chem., 23, 109-112.]). For related structures, see, for example: Ghaemi et al. (2011[Ghaemi, A., Rayati, S., Elahi, E., Ng, S. W. & Tiekink, E. R. T. (2011). Acta Cryst. E67, m1445-m1446.]); Kargar et al. (2011[Kargar, H., Kia, R., Pahlavani, E. & Tahir, M. N. (2011). Acta Cryst. E67, m941.], 2012[Kargar, H., Kia, R., Sharafi, Z. & Tahir, M. N. (2012). Acta Cryst. E68, m82.]).

[Scheme 1]

Experimental

Crystal data
  • [Cu(C21H24N2O4)]·H2O

  • Mr = 449.98

  • Orthorhombic, P b c n

  • a = 20.567 (2) Å

  • b = 12.2647 (14) Å

  • c = 8.4287 (7) Å

  • V = 2126.1 (4) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 1.06 mm−1

  • T = 291 K

  • 0.21 × 0.14 × 0.08 mm

Data collection
  • Bruker SMART APEXII CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2005[Bruker (2005). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.256, Tmax = 0.535

  • 17546 measured reflections

  • 2620 independent reflections

  • 1113 reflections with I > 2σ(I)

  • Rint = 0.115

Refinement
  • R[F2 > 2σ(F2)] = 0.051

  • wR(F2) = 0.140

  • S = 0.98

  • 2620 reflections

  • 134 parameters

  • H-atom parameters constrained

  • Δρmax = 0.28 e Å−3

  • Δρmin = −0.36 e Å−3

Table 1
Selected bond lengths (Å)

N1—Cu1 1.930 (3)
Cu1—O1 1.899 (3)

Table 2
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O1W—H1W⋯O1i 0.89 2.43 3.024 (5) 124
C9—H9A⋯O1ii 0.97 2.59 3.432 (5) 145
Symmetry codes: (i) [-x+1, y, -z-{\script{1\over 2}}]; (ii) -x+1, -y+1, -z.

Data collection: APEX2 (Bruker, 2005[Bruker (2005). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2005[Bruker (2005). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; 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, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

Supporting information


Comment top

Schiff base complexes are one of the most important stereochemical models in transition metal coordination chemistry, with the ease of preparation and structural variations (Granovski et al., 1993; Blower et al., (1998). In continuation of our work on the crystal structures of Schiff base metal complexes (Kargar et al., 2012; Kargar et al., 2011; Ghaemi, et al., (2011), we determined the X-ray structure of the title compound.

The asymmetric unit of the title compound (Fig. 1) comprises a a half of Schiff base complex. The bond lengths (Allen et al., 1987) and angles are within the normal ranges and are comparable to the related structure (Kargar et al., 2012; Kargar et al., 2011; Ghaemi, et al., (2011). The geometry around CuII is a distorted square-planar which is supported by the N2O2 donor atoms of the coordinated Schiff base ligand (Table 1). The dihedral angle between the substituted benzene rings is 42.56 (19)°. Interamolecular O—H···O hydrogen bonds make R12(6) ring motif (Bernstein et al., 1995). The dihedral angle between the symmetry-related benzene rings is 45.54 (19)°. In the crystal structure the molecules are linked together along the c axis, forming a chain through the intermolecular C—H···O interactions (Table 2, Fig. 2).

Related literature top

For standard bond lengths, see: Allen et al. (1987). For hydrogen-bond motifs, see: Bernstein et al. (1995). For applications of Schiff bases in coordination chemistry, see, for example: Granovski et al. (1993); Blower et al. (1998). For related structures, see, for example: Ghaemi, et al., (2011); Kargar et al. (2011, 2012).

Experimental top

The title compound was synthesized by adding 5-methoxy-salicylaldehyde-2,2-dimethyl-1, 3-propanediamine (2 mmol) to a solution of CuCl2. 4H2O (2.1 mmol) in ethanol (30 mL). The mixture was refluxed with stirring for 30 min. The resultant solution was filtered. Dark-green single crystals of the title compound suitable for X-ray structure determination were recrystallized from ethanol by slow evaporation of the solvents at room temperature over several days.

Refinement top

The H-atoms were included in calculated positions and treated as riding atoms: C—H = 0.93, 0.96 and 0.97 Å for CH, CH3 and CH2 H-atoms, respectively, with Uiso (H) = k × Ueq(C), where k = 1.5 for CH3 H-atoms, and k = 1.2 for all other H-atoms.

Structure description top

Schiff base complexes are one of the most important stereochemical models in transition metal coordination chemistry, with the ease of preparation and structural variations (Granovski et al., 1993; Blower et al., (1998). In continuation of our work on the crystal structures of Schiff base metal complexes (Kargar et al., 2012; Kargar et al., 2011; Ghaemi, et al., (2011), we determined the X-ray structure of the title compound.

The asymmetric unit of the title compound (Fig. 1) comprises a a half of Schiff base complex. The bond lengths (Allen et al., 1987) and angles are within the normal ranges and are comparable to the related structure (Kargar et al., 2012; Kargar et al., 2011; Ghaemi, et al., (2011). The geometry around CuII is a distorted square-planar which is supported by the N2O2 donor atoms of the coordinated Schiff base ligand (Table 1). The dihedral angle between the substituted benzene rings is 42.56 (19)°. Interamolecular O—H···O hydrogen bonds make R12(6) ring motif (Bernstein et al., 1995). The dihedral angle between the symmetry-related benzene rings is 45.54 (19)°. In the crystal structure the molecules are linked together along the c axis, forming a chain through the intermolecular C—H···O interactions (Table 2, Fig. 2).

For standard bond lengths, see: Allen et al. (1987). For hydrogen-bond motifs, see: Bernstein et al. (1995). For applications of Schiff bases in coordination chemistry, see, for example: Granovski et al. (1993); Blower et al. (1998). For related structures, see, for example: Ghaemi, et al., (2011); Kargar et al. (2011, 2012).

Computing details top

Data collection: APEX2 (Bruker, 2005); cell refinement: SAINT (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, 2009).

Figures top
[Figure 1] Fig. 1. The ORTEP plot of the title compound, showing 40% probability displacement ellipsoids and the atomic numbering.Intermolecular hydrogen bonds between the complex and crystal water molecule are shown (dashed lines).
[Figure 2] Fig. 2. A part of the packing diagram of the title compound showing a chain formed through the intermolecular C—H···O intearctions along the c axis (dashed lines). Only the H atoms involved in the interactions are shown.
{4,4'-Dimethoxy-2,2'-[2,2-dimethylpropane-1,3- diylbis(nitrilomethanylylidene)]diphenolato}copper(II) monohydrate top
Crystal data top
[Cu(C21H24N2O4)]·H2OF(000) = 940
Mr = 449.98Dx = 1.406 Mg m3
Orthorhombic, PbcnMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2n 2abCell parameters from 2169 reflections
a = 20.567 (2) Åθ = 2.5–27.4°
b = 12.2647 (14) ŵ = 1.06 mm1
c = 8.4287 (7) ÅT = 291 K
V = 2126.1 (4) Å3Block, dark-green
Z = 40.21 × 0.14 × 0.08 mm
Data collection top
Bruker SMART APEXII CCD area-detector
diffractometer
2620 independent reflections
Radiation source: fine-focus sealed tube1113 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.115
φ and ω scansθmax = 28.3°, θmin = 3.1°
Absorption correction: multi-scan
(SADABS; Bruker, 2005)
h = 2727
Tmin = 0.256, Tmax = 0.535k = 1616
17546 measured reflectionsl = 108
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)] = 0.051Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.140H-atom parameters constrained
S = 0.98 w = 1/[σ2(Fo2) + (0.0498P)2 + 0.1009P]
where P = (Fo2 + 2Fc2)/3
2620 reflections(Δ/σ)max < 0.001
134 parametersΔρmax = 0.28 e Å3
0 restraintsΔρmin = 0.36 e Å3
Crystal data top
[Cu(C21H24N2O4)]·H2OV = 2126.1 (4) Å3
Mr = 449.98Z = 4
Orthorhombic, PbcnMo Kα radiation
a = 20.567 (2) ŵ = 1.06 mm1
b = 12.2647 (14) ÅT = 291 K
c = 8.4287 (7) Å0.21 × 0.14 × 0.08 mm
Data collection top
Bruker SMART APEXII CCD area-detector
diffractometer
2620 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2005)
1113 reflections with I > 2σ(I)
Tmin = 0.256, Tmax = 0.535Rint = 0.115
17546 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0510 restraints
wR(F2) = 0.140H-atom parameters constrained
S = 0.98Δρmax = 0.28 e Å3
2620 reflectionsΔρmin = 0.36 e Å3
134 parameters
Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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 > 2sigma(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
O1W0.50000.1449 (4)0.25000.136 (2)
H1W0.51990.19070.18310.205*
N10.44802 (15)0.5832 (3)0.1447 (3)0.0486 (8)
C10.37450 (19)0.3777 (3)0.1853 (4)0.0476 (10)
C20.3307 (2)0.2908 (3)0.2041 (5)0.0616 (12)
H10.34480.22710.25310.074*
C30.2675 (2)0.2974 (3)0.1520 (5)0.0642 (12)
H30.23950.23890.16820.077*
C40.24498 (19)0.3899 (3)0.0757 (5)0.0547 (11)
C50.28556 (19)0.4760 (3)0.0581 (5)0.0516 (10)
H50.27030.53880.00870.062*
C60.35058 (18)0.4730 (3)0.1130 (4)0.0459 (9)
C70.1550 (2)0.4783 (4)0.0455 (6)0.0796 (15)
H7A0.17930.49470.13990.119*
H7B0.11040.46500.07300.119*
H7C0.15750.53890.02640.119*
C80.38928 (18)0.5688 (3)0.0937 (4)0.0480 (10)
H80.37040.62650.03900.058*
C90.4810 (2)0.6853 (4)0.1061 (5)0.0596 (12)
H9A0.51970.66910.04500.072*
H9B0.45250.72900.04000.072*
C100.50000.7548 (5)0.25000.0626 (16)
C110.4427 (3)0.8223 (5)0.3009 (7)0.139 (3)
H11A0.45460.86610.39060.209*
H11B0.42950.86880.21500.209*
H11C0.40730.77510.32940.209*
Cu10.50000.47397 (6)0.25000.0496 (3)
O10.43439 (12)0.3654 (2)0.2370 (3)0.0530 (7)
O30.18104 (14)0.3856 (3)0.0270 (4)0.0734 (9)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O1W0.216 (7)0.081 (4)0.113 (5)0.0000.022 (4)0.000
N10.045 (2)0.060 (2)0.041 (2)0.0107 (18)0.0028 (15)0.0045 (16)
C10.048 (3)0.052 (3)0.043 (2)0.001 (2)0.0030 (19)0.0007 (19)
C20.058 (3)0.049 (3)0.078 (3)0.002 (2)0.010 (2)0.009 (2)
C30.054 (3)0.054 (3)0.085 (3)0.011 (2)0.010 (2)0.005 (2)
C40.040 (2)0.059 (3)0.065 (3)0.001 (2)0.003 (2)0.004 (2)
C50.046 (2)0.054 (3)0.054 (2)0.003 (2)0.005 (2)0.003 (2)
C60.043 (2)0.048 (2)0.046 (2)0.000 (2)0.0001 (18)0.000 (2)
C70.053 (3)0.091 (4)0.095 (4)0.008 (3)0.019 (3)0.006 (3)
C80.048 (2)0.050 (3)0.046 (2)0.002 (2)0.002 (2)0.0086 (19)
C90.056 (3)0.068 (3)0.054 (3)0.015 (2)0.003 (2)0.008 (2)
C100.072 (4)0.054 (4)0.062 (4)0.0000.006 (4)0.000
C110.178 (7)0.137 (5)0.102 (4)0.106 (5)0.047 (4)0.041 (4)
Cu10.0406 (4)0.0587 (5)0.0494 (4)0.0000.0029 (3)0.000
O10.0433 (15)0.0533 (17)0.0624 (18)0.0010 (12)0.0043 (15)0.0051 (14)
O30.0435 (17)0.073 (2)0.104 (3)0.0068 (16)0.0141 (16)0.0039 (18)
Geometric parameters (Å, º) top
O1W—H1W0.8940C7—H7A0.9600
N1—C81.295 (4)C7—H7B0.9600
N1—C91.460 (5)C7—H7C0.9600
N1—Cu11.930 (3)C8—H80.9300
C1—O11.315 (4)C9—C101.533 (5)
C1—C21.405 (5)C9—H9A0.9691
C1—C61.407 (5)C9—H9B0.9699
C2—C31.374 (5)C10—C11i1.503 (6)
C2—H10.9300C10—C111.503 (6)
C3—C41.384 (5)C10—C9i1.533 (5)
C3—H30.9300C11—H11A0.9600
C4—C51.354 (5)C11—H11B0.9600
C4—O31.379 (4)C11—H11C0.9600
C5—C61.415 (5)Cu1—O11.899 (3)
C5—H50.9300Cu1—O1i1.899 (3)
C6—C81.429 (5)Cu1—N1i1.930 (3)
C7—O31.398 (5)
C8—N1—C9118.5 (3)N1—C8—H8116.8
C8—N1—Cu1125.1 (3)C6—C8—H8116.8
C9—N1—Cu1116.1 (3)N1—C9—C10114.7 (3)
O1—C1—C2118.5 (4)N1—C9—H9A108.9
O1—C1—C6124.5 (4)C10—C9—H9A108.9
C2—C1—C6117.0 (4)N1—C9—H9B108.8
C3—C2—C1121.8 (4)C10—C9—H9B107.6
C3—C2—H1119.1H9A—C9—H9B107.7
C1—C2—H1119.1C11i—C10—C11113.1 (7)
C2—C3—C4120.8 (4)C11i—C10—C9i109.4 (3)
C2—C3—H3119.6C11—C10—C9i106.3 (3)
C4—C3—H3119.6C11i—C10—C9106.3 (3)
C5—C4—O3125.9 (4)C11—C10—C9109.4 (3)
C5—C4—C3119.0 (4)C9i—C10—C9112.5 (5)
O3—C4—C3115.2 (4)C10—C11—H11A109.5
C4—C5—C6121.7 (4)C10—C11—H11B109.5
C4—C5—H5119.1H11A—C11—H11B109.5
C6—C5—H5119.1C10—C11—H11C109.5
C1—C6—C5119.6 (4)H11A—C11—H11C109.5
C1—C6—C8122.5 (4)H11B—C11—H11C109.5
C5—C6—C8117.9 (4)O1—Cu1—O1i90.97 (15)
O3—C7—H7A109.5O1—Cu1—N1i155.08 (11)
O3—C7—H7B109.5O1i—Cu1—N1i93.83 (12)
H7A—C7—H7B109.5O1—Cu1—N193.83 (12)
O3—C7—H7C109.5O1i—Cu1—N1155.08 (11)
H7A—C7—H7C109.5N1i—Cu1—N192.05 (18)
H7B—C7—H7C109.5C1—O1—Cu1127.2 (2)
N1—C8—C6126.5 (4)C4—O3—C7117.6 (3)
O1—C1—C2—C3179.5 (4)Cu1—N1—C9—C1068.1 (4)
C6—C1—C2—C31.1 (6)N1—C9—C10—C11i153.9 (4)
C1—C2—C3—C41.3 (7)N1—C9—C10—C1183.7 (5)
C2—C3—C4—C52.4 (7)N1—C9—C10—C9i34.2 (2)
C2—C3—C4—O3179.0 (4)C8—N1—Cu1—O10.3 (3)
O3—C4—C5—C6179.6 (4)C9—N1—Cu1—O1172.8 (3)
C3—C4—C5—C61.2 (6)C8—N1—Cu1—O1i100.9 (4)
O1—C1—C6—C5178.4 (3)C9—N1—Cu1—O1i72.2 (4)
C2—C1—C6—C52.2 (6)C8—N1—Cu1—N1i155.4 (4)
O1—C1—C6—C82.4 (6)C9—N1—Cu1—N1i31.4 (2)
C2—C1—C6—C8177.0 (3)C2—C1—O1—Cu1171.9 (3)
C4—C5—C6—C11.1 (6)C6—C1—O1—Cu17.5 (5)
C4—C5—C6—C8178.1 (3)O1i—Cu1—O1—C1161.4 (3)
C9—N1—C8—C6176.9 (3)N1i—Cu1—O1—C197.4 (4)
Cu1—N1—C8—C63.9 (5)N1—Cu1—O1—C15.9 (3)
C1—C6—C8—N13.7 (6)C5—C4—O3—C70.8 (6)
C5—C6—C8—N1175.6 (4)C3—C4—O3—C7177.7 (4)
C8—N1—C9—C10118.3 (4)
Symmetry code: (i) x+1, y, z1/2.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1W—H1W···O1i0.892.433.024 (5)124
C9—H9A···O1ii0.972.593.432 (5)145
Symmetry codes: (i) x+1, y, z1/2; (ii) x+1, y+1, z.

Experimental details

Crystal data
Chemical formula[Cu(C21H24N2O4)]·H2O
Mr449.98
Crystal system, space groupOrthorhombic, Pbcn
Temperature (K)291
a, b, c (Å)20.567 (2), 12.2647 (14), 8.4287 (7)
V3)2126.1 (4)
Z4
Radiation typeMo Kα
µ (mm1)1.06
Crystal size (mm)0.21 × 0.14 × 0.08
Data collection
DiffractometerBruker SMART APEXII CCD area-detector
Absorption correctionMulti-scan
(SADABS; Bruker, 2005)
Tmin, Tmax0.256, 0.535
No. of measured, independent and
observed [I > 2σ(I)] reflections
17546, 2620, 1113
Rint0.115
(sin θ/λ)max1)0.666
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.051, 0.140, 0.98
No. of reflections2620
No. of parameters134
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.28, 0.36

Computer programs: APEX2 (Bruker, 2005), SAINT (Bruker, 2005), SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Selected bond lengths (Å) top
N1—Cu11.930 (3)Cu1—O11.899 (3)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1W—H1W···O1i0.892.433.024 (5)124
C9—H9A···O1ii0.972.593.432 (5)145
Symmetry codes: (i) x+1, y, z1/2; (ii) x+1, y+1, z.
 

Acknowledgements

HK and FG thank PNU for the financial support. MNT thanks the University of Sargodha for the research facility.

References

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