Bis{2-[(2-cyano­phen­yl)imino­meth­yl]phenolato}copper(II)

In the title mononuclear copper(II) complex, [Cu(C₁₄H₉N₂O)₂], the Cu^II atom, situated on an inversion centre, shows a slightly distorted square-planar geometry and is coordinated by the N and O atoms from two deprotonated symmetry-related Schiff base ligands. The Cu-N and Cu-O bond lengths are 2.009 (2) and 1.888 (2) Å, respectively. The dihedral angle between the cyano­phenyl rings and phenolate rings is 42.28 (13)°.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.005 Å
• R factor = 0.050
• wR factor = 0.125
• Data-to-parameter ratio = 16.4

checkCIF/PLATON results

No syntax errors found



Alert level C
            Value of measurement temperature given =   293.000
            Value of melting point given =     0.000
PLAT230_ALERT_2_C Hirshfeld Test Diff for    C9     --  C14     ..       5.12 su
PLAT371_ALERT_2_C Long   C(sp2)-C(sp1) Bond  C9     -   C14    ...       1.44 Ang.
PLAT062_ALERT_4_C Rescale T(min) & T(max) by .....................       0.91
PLAT153_ALERT_1_C The su's on the Cell Axes   are Equal (x 100000)        300 Ang.
PLAT234_ALERT_4_C Large Hirshfeld Difference N2     --  C14     ..       0.11  Ang.

Alert level G
ABSTM02_ALERT_3_G  When printed, the submitted absorption T values will be
            replaced by the scaled T values. Since the ratio of scaled T's
            is identical to the ratio of reported T values, the scaling
            does not imply a change to the absorption corrections used in
            the study.
            Ratio of Tmax expected/reported      0.906
            Tmax scaled      0.906 Tmin scaled      0.824
PLAT199_ALERT_1_G Check the Reported _cell_measurement_temperature        293 K
PLAT200_ALERT_1_G Check the Reported _diffrn_ambient_temperature .        293 K

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   5 ALERT level C = Check and explain
   3 ALERT level G = General alerts; check

   3 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   2 ALERT type 2 Indicator that the structure model may be wrong or deficient
   1 ALERT type 3 Indicator that the structure quality may be low
   2 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

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S1. Comment

Metal derivatives of Schiff bases have been studied extensively, and copper(II) and nickel(II) complexes play an important role in both synthetic and structural research. These complexes have received much attention in recent years (Marganian et al., 1995; Kitaura et al. 2004). We have reported previously the crystal structures of monomeric Schiff base complexes of Ni^II (Gong et al., 2008). As an a continuation of our research on the synthesis and structure of transition metal complexesof Schiff base compounds, we here report the results of the reaction of copper(II) with the didentate ligand 2-(2-cyanophenyliminomethyl)phenol, forming the title compound (I).

Fig.1 shows the molecular structure of the title compound. The copper(II) is coordinated by the two imine N and two phenolate O atoms of the two Schiff base ligands in a slightly distorted square-planar geometry in a trans arrangement. 2-(2-cyanophenyliminomethyl)phenol loses a proton form the hydroxyl group and acts as a singlely charged bidentate ligand coordinating to Copper(II) through the phenolate O and imine N atoms. The dihedral angle between the C1—C6 and C8—C13 benzene rings is 42.28 (0.13)°. The N1—Cu1—O1 bond angles is 90.78 (9)°. The two equivalent Cu–N and Cu–O distances are 2.009 (2)Å and 1.888 (2) Å, respectively. All these parameters conform to values in other square-planar-coordinated copper(II) compounds(Jian et al., 2004; Ünver 2002).

Related literature

For Schiff base complexes with copper(II) and nickel(II), see: Gong et al. (2008); Kitaura et al. (2004); Marganian et al. (1995). For bond-length data, see: Jian et al. (2004); Ünver (2002). For a related structure, see: Xia et al. (2008).

S2. Experimental

2-(2-Cyanophenyliminomethyl)phenol was prepared according to the literature(Xia et al., 2008).CuCl₂.2H₂O(17. mg, 0.1 mmol) in methanol (5 ml) was added to the solution of 2-(2-cyanophenyliminomethyl)phenol (22.2 mg, 0.1 mmol)in the methanol (5 ml), pH of themixture was adjusted to 8–9 and stirred for 4 h. The filtrate was kept at room temperature for about two weeks, and green block crystals of (I) for X-ray single-crystal investigation were obtained.

S3. Refinement

All H atoms attached to C atoms were fixed geometrically and treated as riding with C—H = 0.93 Å and U_iso(H) = 1.2U_eq(C).

Computing details

Data collection: CrystalClear (Rigaku, 2005); cell refinement: CrystalClear (Rigaku, 2005); data reduction: CrystalClear (Rigaku, 2005); 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

Fig. 1. Molecular view of the title compound with the atom-labelling scheme. Displacement ellipsoids are drawn at the 30% probability level. H atoms are represented as small spheres of arbitrary radii. [Symmetry code: (i) 2 - x, 1 - y, -z]

Bis{2-[(2-cyanophenyl)iminomethyl]phenolato}copper(II)

Crystal data

[Cu(C14H9N2O)2]	F(000) = 518
Mr = 506.00	Dx = 1.464 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 2373 reflections
a = 9.698 (3) Å	θ = 3.1–27.4°
b = 11.403 (3) Å	µ = 0.99 mm^−1
c = 10.889 (3) Å	T = 293 K
β = 107.570 (11)°	Block, red
V = 1148.0 (6) Å^3	0.15 × 0.10 × 0.10 mm
Z = 2

Data collection

Rigaku Mercury2 diffractometer	2629 independent reflections
Radiation source: fine-focus sealed tube	1952 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.057
Detector resolution: 13.6612 pixels mm^-1	θmax = 27.5°, θmin = 3.1°
ω scans	h = −12→12
Absorption correction: multi-scan (CrystalClear; Rigaku, 2005)	k = −14→14
Tmin = 0.909, Tmax = 1.000	l = −14→14
11307 measured reflections

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.050	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.125	H-atom parameters constrained
S = 1.09	w = 1/[σ^2(Fo^2) + (0.0516P)^2 + 0.2943P] where P = (Fo^2 + 2Fc^2)/3
2629 reflections	(Δ/σ)max < 0.001
160 parameters	Δρmax = 0.26 e Å^−3
0 restraints	Δρmin = −0.43 e Å^−3

Special details

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 (Ų)

	x	y	z	Uiso*/Ueq
Cu1	1.0000	0.5000	0.0000	0.03878 (18)
N1	0.9612 (2)	0.6674 (2)	0.0368 (2)	0.0383 (5)
O1	1.0810 (2)	0.46983 (18)	0.1778 (2)	0.0469 (5)
C8	0.8569 (3)	0.7359 (3)	−0.0563 (3)	0.0400 (6)
C1	1.1420 (3)	0.6686 (3)	0.2473 (3)	0.0416 (7)
C7	1.0377 (3)	0.7214 (3)	0.1397 (3)	0.0416 (7)
H7A	1.0234	0.8018	0.1439	0.050*
C9	0.7154 (3)	0.6925 (3)	−0.1043 (3)	0.0469 (7)
C2	1.1568 (3)	0.5450 (3)	0.2631 (3)	0.0403 (7)
C4	1.3310 (4)	0.5785 (3)	0.4717 (3)	0.0587 (9)
H4A	1.3938	0.5479	0.5471	0.070*
C6	1.2221 (3)	0.7432 (3)	0.3469 (3)	0.0535 (8)
H6A	1.2098	0.8239	0.3373	0.064*
C13	0.8922 (4)	0.8413 (3)	−0.1019 (3)	0.0507 (8)
H13A	0.9852	0.8715	−0.0698	0.061*
C14	0.6811 (3)	0.5801 (3)	−0.0602 (3)	0.0539 (8)
C10	0.6108 (4)	0.7564 (4)	−0.1967 (3)	0.0624 (10)
H10A	0.5162	0.7291	−0.2270	0.075*
C12	0.7880 (5)	0.9012 (3)	−0.1957 (4)	0.0670 (10)
H12A	0.8126	0.9711	−0.2280	0.080*
C5	1.3176 (4)	0.6996 (3)	0.4574 (3)	0.0601 (9)
H5A	1.3720	0.7496	0.5211	0.072*
C3	1.2547 (4)	0.5035 (3)	0.3782 (3)	0.0507 (8)
H3A	1.2678	0.4231	0.3909	0.061*
N2	0.6591 (4)	0.4905 (3)	−0.0242 (4)	0.0716 (9)
C11	0.6491 (5)	0.8599 (4)	−0.2422 (4)	0.0729 (12)
H11A	0.5805	0.9021	−0.3049	0.087*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Cu1	0.0424 (3)	0.0348 (3)	0.0347 (3)	0.0037 (2)	0.0050 (2)	−0.0003 (2)
N1	0.0399 (13)	0.0373 (13)	0.0349 (12)	0.0036 (10)	0.0069 (10)	0.0010 (10)
O1	0.0581 (14)	0.0381 (12)	0.0378 (12)	0.0047 (9)	0.0046 (10)	−0.0004 (8)
C8	0.0428 (16)	0.0400 (16)	0.0340 (15)	0.0077 (12)	0.0066 (12)	−0.0006 (12)
C1	0.0385 (16)	0.0445 (17)	0.0373 (16)	0.0018 (12)	0.0044 (12)	−0.0004 (12)
C7	0.0445 (17)	0.0332 (15)	0.0433 (16)	0.0020 (12)	0.0074 (13)	−0.0001 (12)
C9	0.0429 (18)	0.0526 (19)	0.0407 (17)	0.0068 (14)	0.0059 (13)	−0.0004 (14)
C2	0.0407 (17)	0.0443 (16)	0.0349 (15)	0.0040 (13)	0.0098 (13)	0.0009 (12)
C4	0.050 (2)	0.073 (3)	0.0432 (19)	0.0075 (17)	−0.0005 (15)	0.0027 (16)
C6	0.058 (2)	0.0493 (19)	0.0458 (19)	−0.0028 (15)	0.0038 (15)	−0.0048 (14)
C13	0.057 (2)	0.0476 (18)	0.0479 (19)	0.0047 (15)	0.0162 (15)	0.0054 (14)
C14	0.0386 (18)	0.071 (2)	0.0456 (19)	−0.0032 (16)	0.0030 (14)	−0.0054 (17)
C10	0.046 (2)	0.081 (3)	0.050 (2)	0.0174 (18)	−0.0011 (16)	0.0000 (18)
C12	0.092 (3)	0.051 (2)	0.055 (2)	0.0172 (19)	0.018 (2)	0.0155 (16)
C5	0.061 (2)	0.065 (2)	0.0416 (19)	−0.0074 (17)	−0.0045 (16)	−0.0060 (16)
C3	0.056 (2)	0.0516 (19)	0.0402 (17)	0.0096 (15)	0.0080 (14)	0.0061 (14)
N2	0.064 (2)	0.067 (2)	0.077 (2)	−0.0158 (16)	0.0115 (17)	0.0050 (17)
C11	0.079 (3)	0.073 (3)	0.055 (2)	0.036 (2)	0.003 (2)	0.0149 (19)

Geometric parameters (Å, º)

Cu1—O1^i	1.888 (2)	C4—C3	1.364 (4)
Cu1—O1	1.888 (2)	C4—C5	1.391 (5)
Cu1—N1^i	2.009 (2)	C4—H4A	0.9300
Cu1—N1	2.009 (2)	C6—C5	1.371 (4)
N1—C7	1.298 (3)	C6—H6A	0.9300
N1—C8	1.429 (3)	C13—C12	1.381 (4)
O1—C2	1.313 (4)	C13—H13A	0.9300
C8—C13	1.382 (4)	C14—N2	1.137 (4)
C8—C9	1.403 (4)	C10—C11	1.374 (5)
C1—C2	1.421 (4)	C10—H10A	0.9300
C1—C6	1.413 (4)	C12—C11	1.372 (5)
C1—C7	1.429 (4)	C12—H12A	0.9300
C7—H7A	0.9300	C5—H5A	0.9300
C9—C10	1.398 (4)	C3—H3A	0.9300
C9—C14	1.443 (5)	C11—H11A	0.9300
C2—C3	1.407 (4)
O1^i—Cu1—O1	180.00 (12)	C3—C4—C5	121.9 (3)
O1^i—Cu1—N1^i	90.78 (9)	C3—C4—H4A	119.1
O1—Cu1—N1^i	89.22 (9)	C5—C4—H4A	119.1
O1^i—Cu1—N1	89.22 (9)	C5—C6—C1	121.7 (3)
O1—Cu1—N1	90.78 (9)	C5—C6—H6A	119.2
N1^i—Cu1—N1	180.00 (13)	C1—C6—H6A	119.2
C7—N1—C8	116.8 (2)	C8—C13—C12	119.4 (3)
C7—N1—Cu1	122.03 (19)	C8—C13—H13A	120.3
C8—N1—Cu1	120.84 (18)	C12—C13—H13A	120.3
C2—O1—Cu1	125.24 (19)	N2—C14—C9	177.6 (4)
C13—C8—C9	119.5 (3)	C11—C10—C9	119.4 (3)
C13—C8—N1	122.1 (3)	C11—C10—H10A	120.3
C9—C8—N1	118.4 (3)	C9—C10—H10A	120.3
C2—C1—C6	119.5 (3)	C11—C12—C13	121.3 (4)
C2—C1—C7	122.5 (3)	C11—C12—H12A	119.3
C6—C1—C7	117.7 (3)	C13—C12—H12A	119.3
N1—C7—C1	125.9 (3)	C6—C5—C4	118.3 (3)
N1—C7—H7A	117.1	C6—C5—H5A	120.9
C1—C7—H7A	117.1	C4—C5—H5A	120.9
C8—C9—C10	120.0 (3)	C4—C3—C2	121.5 (3)
C8—C9—C14	119.1 (3)	C4—C3—H3A	119.3
C10—C9—C14	120.8 (3)	C2—C3—H3A	119.3
O1—C2—C3	119.6 (3)	C12—C11—C10	120.3 (3)
O1—C2—C1	123.2 (3)	C12—C11—H11A	119.9
C3—C2—C1	117.2 (3)	C10—C11—H11A	119.9

Symmetry code: (i) −x+2, −y+1, −z.