Bis{1-[(4-methyl­phen­yl)imino­meth­yl]-2-naphtho­lato-κ²N,O}copper(II)

In the title complex, [Cu(C₁₈H₁₄NO)₂], the Cu^II ion lies on an inversion center and is coordinated in a slightly distorted square-planar environment. The 1-[(4-methyl­phen­yl)imino­meth­yl]-2-naphtho­late ligands are coordinated in a trans arrangement with respect to the N and O atoms.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.032
• wR factor = 0.076
• Data-to-parameter ratio = 15.3

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT910_ALERT_3_C Missing # of FCF Reflections Below Th(Min) .....          4
PLAT911_ALERT_3_C Missing # FCF Refl Between THmin & STh/L=  0.600          7
PLAT912_ALERT_4_C Missing # of FCF Reflections Above STh/L=  0.600          2

Alert level G
PLAT154_ALERT_1_G The su's on the Cell Angles are Equal  (x 10000)        700 Deg.
PLAT199_ALERT_1_G Check the Reported _cell_measurement_temperature        293 K
PLAT200_ALERT_1_G Check the Reported   _diffrn_ambient_temperature        293 K
PLAT710_ALERT_4_G Delete 1-2-3 or 2-3-4 Linear Torsion Angle ... #          1
            O   -CU1 -O   -C2      7.00  0.00   2.655   1.555   1.555   1.555
PLAT710_ALERT_4_G Delete 1-2-3 or 2-3-4 Linear Torsion Angle ... #          6
            N   -CU1 -N   -C1      2.00  0.00   2.655   1.555   1.555   1.555
PLAT710_ALERT_4_G Delete 1-2-3 or 2-3-4 Linear Torsion Angle ... #          9
            N   -CU1 -N   -C      16.00  0.00   2.655   1.555   1.555   1.555

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

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

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S1. Comment

Schiff bases and their metal complexes have aroused considerable attention, mainly because of their interesting structures and potential applications, e.g. catalytic activity (Henrici-Olive & Olive et al., 1984), photochromic properties (Cohen et al., 1964), biological activity (Barton et al., 1979). Additionally, copper (II) complexes of Schiff bases have been reported for their applications in the design and construction of new magnetic materials (Erxleben & Schumacher, 2001), and their cellular proteasome activity (Adsule et al., 2006). Herein we report the synthesis and crystal structure of the title complex.

The molecular structure of the title complex is shown in Fig. 1. The Cu^II ion is coordinated by two O atoms and two N atoms of two bidentate schiff base ligands to form a square-planar geometry in a trans arrangement. The Cu—N and Cu—O bond lengths agree with those in related complexes (e.g. Kani et al., 1998; Lo et al., 1997; Ünver, 2002).

Related literature

For background information and applications of Schiff base complexes, see: Adsule et al. (2006); Barton et al. (1979); Cohen et al. (1964); Henrici-Olive & Olive (1984); Erxleben & Schumacher (2001). For related structures, see: Kani et al. (1998); Lo et al. (1997); Ünver (2002).

S2. Experimental

Copper(II) acetate hydrate (0.199 g, 0.001 mol) in methanol (50 ml) and N-(p-Tolyl)-2-hydroxy-1-naphthaldimine (0.586 g, 0.002 mol) in acetonitrile(75 ml) were mixed and heated at 333 K for 1 h. The solution was filtered and the filtrate kept in a beaker at room temperature for crystallization. Black crystals started appearing after 3 days and were then collected, 0.621 g (79%) yields.

S3. Refinement

Hydrogen atoms were placed in calculated positions and refined using a riding-model approximation with C—H = 0.93 Å, U_iso = 1.2U_eq (C) for aromatic H atoms and C—H = 0.96 Å, U_iso = 1.5U_eq (C) for methyl H atoms.

Computing details

Data collection: APEX2 (Bruker, 2004); cell refinement: SAINT-Plus (Bruker, 2001); data reduction: SAINT-Plus (Bruker, 2001); 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: SHELXTL (Sheldrick, 2008).

Figures

Fig. 1. The molecular structure, with atom labels and 25% probability displacement ellipsoids for non-H atoms (symmetry code: (A) -x+1, -y, -z).

Bis{1-[(4-methylphenyl)iminomethyl]-2-naphtholato- κ²N,O}copper(II)

Crystal data

[Cu(C18H14NO)2]	Z = 1
Mr = 584.14	F(000) = 303
Triclinic, P1	Dx = 1.370 Mg m^−3
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 7.0948 (6) Å	Cell parameters from 1252 reflections
b = 10.2335 (7) Å	θ = 2.5–23.9°
c = 10.5784 (10) Å	µ = 0.81 mm^−1
α = 104.559 (7)°	T = 293 K
β = 98.728 (7)°	Block, black
γ = 102.573 (7)°	0.25 × 0.12 × 0.11 mm
V = 708.01 (10) Å^3

Data collection

Bruker APEXII CCD area-detector diffractometer	2878 independent reflections
Radiation source: fine-focus sealed tube	2395 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.028
φ and ω scans	θmax = 26.4°, θmin = 3.2°
Absorption correction: multi-scan (SADABS; Sheldrick, 2003)	h = −8→8
Tmin = 0.824, Tmax = 0.916	k = −12→12
7213 measured reflections	l = −13→13

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)] = 0.032	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.076	H-atom parameters constrained
S = 1.01	w = 1/[σ^2(Fo^2) + (0.0431P)^2] where P = (Fo^2 + 2Fc^2)/3
2878 reflections	(Δ/σ)max = 0.001
188 parameters	Δρmax = 0.24 e Å^−3
0 restraints	Δρmin = −0.18 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	0.5000	0.0000	0.0000	0.03685 (13)
O	0.63653 (18)	−0.08439 (14)	0.10934 (13)	0.0465 (3)
N	0.3572 (2)	0.06231 (15)	0.14161 (14)	0.0353 (3)
C	0.2582 (3)	0.17043 (18)	0.14181 (17)	0.0348 (4)
C1	0.3384 (3)	0.00334 (19)	0.23682 (18)	0.0374 (4)
H1	0.2561	0.0326	0.2922	0.045*
C2	0.5826 (3)	−0.13173 (18)	0.20525 (18)	0.0380 (4)
C5	0.0594 (3)	0.14665 (19)	0.14435 (19)	0.0403 (4)
H5	−0.0138	0.0584	0.1419	0.048*
C6	−0.0300 (3)	0.2550 (2)	0.15063 (19)	0.0464 (5)
H6	−0.1636	0.2380	0.1525	0.056*
C7	0.3611 (3)	0.30083 (19)	0.13974 (19)	0.0443 (5)
H7	0.4929	0.3167	0.1332	0.053*
C8	0.3767 (3)	−0.16156 (19)	0.37004 (18)	0.0397 (4)
C9	0.0726 (3)	0.3872 (2)	0.15411 (19)	0.0459 (5)
C10	0.4283 (3)	−0.09993 (19)	0.26615 (18)	0.0366 (4)
C12	0.2192 (3)	−0.1408 (2)	0.43269 (19)	0.0481 (5)
H12	0.1454	−0.0824	0.4091	0.058*
C14	0.4870 (3)	−0.24967 (19)	0.41041 (19)	0.0452 (5)
C15	0.2694 (3)	0.4076 (2)	0.1473 (2)	0.0493 (5)
H15	0.3417	0.4952	0.1478	0.059*
C17	−0.0240 (4)	0.5069 (2)	0.1698 (3)	0.0680 (7)
H17A	−0.1612	0.4714	0.1253	0.102*
H17B	0.0411	0.5744	0.1308	0.102*
H17C	−0.0132	0.5507	0.2631	0.102*
C18	0.6458 (3)	−0.2737 (2)	0.3493 (2)	0.0530 (5)
H18	0.7205	−0.3293	0.3779	0.064*
C19	0.1725 (3)	−0.2047 (2)	0.5277 (2)	0.0595 (6)
H19	0.0684	−0.1889	0.5678	0.071*
C20	0.6920 (3)	−0.2190 (2)	0.2516 (2)	0.0493 (5)
H20	0.7966	−0.2380	0.2136	0.059*
C21	0.2798 (4)	−0.2931 (2)	0.5642 (2)	0.0651 (6)
H21	0.2455	−0.3379	0.6270	0.078*
C23	0.4339 (4)	−0.3138 (2)	0.5084 (2)	0.0602 (6)
H23	0.5067	−0.3714	0.5350	0.072*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Cu1	0.03127 (19)	0.0423 (2)	0.0432 (2)	0.01461 (14)	0.01515 (13)	0.01531 (15)
O	0.0397 (7)	0.0623 (9)	0.0530 (8)	0.0251 (7)	0.0218 (6)	0.0273 (7)
N	0.0314 (8)	0.0371 (8)	0.0410 (9)	0.0132 (7)	0.0112 (6)	0.0126 (7)
C	0.0350 (9)	0.0366 (10)	0.0338 (10)	0.0135 (8)	0.0105 (7)	0.0072 (8)
C1	0.0311 (9)	0.0421 (11)	0.0391 (11)	0.0110 (8)	0.0121 (8)	0.0083 (9)
C2	0.0334 (10)	0.0379 (10)	0.0413 (11)	0.0095 (8)	0.0072 (8)	0.0100 (9)
C5	0.0370 (10)	0.0388 (10)	0.0472 (11)	0.0122 (8)	0.0149 (8)	0.0110 (9)
C6	0.0369 (10)	0.0510 (12)	0.0538 (12)	0.0192 (9)	0.0159 (9)	0.0098 (10)
C7	0.0342 (10)	0.0436 (11)	0.0559 (13)	0.0101 (9)	0.0109 (8)	0.0157 (10)
C8	0.0415 (10)	0.0365 (10)	0.0368 (10)	0.0058 (8)	0.0065 (8)	0.0086 (8)
C9	0.0523 (12)	0.0435 (12)	0.0434 (11)	0.0232 (10)	0.0105 (9)	0.0067 (9)
C10	0.0349 (10)	0.0374 (10)	0.0373 (10)	0.0095 (8)	0.0082 (7)	0.0107 (8)
C12	0.0501 (12)	0.0532 (13)	0.0444 (12)	0.0134 (10)	0.0153 (9)	0.0179 (10)
C14	0.0548 (12)	0.0391 (11)	0.0396 (11)	0.0107 (9)	0.0063 (9)	0.0120 (9)
C15	0.0516 (12)	0.0363 (11)	0.0581 (13)	0.0090 (10)	0.0085 (10)	0.0148 (10)
C17	0.0777 (17)	0.0590 (14)	0.0781 (17)	0.0410 (13)	0.0208 (13)	0.0175 (13)
C18	0.0584 (13)	0.0500 (13)	0.0570 (14)	0.0249 (11)	0.0082 (10)	0.0210 (11)
C19	0.0625 (14)	0.0696 (15)	0.0463 (13)	0.0101 (12)	0.0208 (10)	0.0184 (12)
C20	0.0465 (12)	0.0539 (13)	0.0569 (13)	0.0255 (10)	0.0160 (9)	0.0195 (11)
C21	0.0892 (18)	0.0648 (15)	0.0485 (13)	0.0162 (14)	0.0222 (12)	0.0289 (12)
C23	0.0826 (17)	0.0534 (14)	0.0500 (13)	0.0206 (12)	0.0130 (12)	0.0233 (11)

Geometric parameters (Å, º)

Cu1—O^i	1.8837 (12)	C8—C14	1.417 (3)
Cu1—O	1.8837 (12)	C8—C10	1.452 (3)
Cu1—N	1.9848 (14)	C9—C15	1.382 (3)
Cu1—N^i	1.9848 (14)	C9—C17	1.515 (2)
O—C2	1.302 (2)	C12—C19	1.373 (3)
N—C1	1.307 (2)	C12—H12	0.9300
N—C	1.434 (2)	C14—C23	1.414 (3)
C—C7	1.382 (2)	C14—C18	1.417 (3)
C—C5	1.384 (2)	C15—H15	0.9300
C1—C10	1.420 (2)	C17—H17A	0.9600
C1—H1	0.9300	C17—H17B	0.9600
C2—C10	1.408 (2)	C17—H17C	0.9600
C2—C20	1.431 (2)	C18—C20	1.343 (3)
C5—C6	1.385 (2)	C18—H18	0.9300
C5—H5	0.9300	C19—C21	1.390 (3)
C6—C9	1.378 (3)	C19—H19	0.9300
C6—H6	0.9300	C20—H20	0.9300
C7—C15	1.380 (2)	C21—C23	1.350 (3)
C7—H7	0.9300	C21—H21	0.9300
C8—C12	1.411 (3)	C23—H23	0.9300
O^i—Cu1—O	180	C2—C10—C1	120.13 (16)
O^i—Cu1—N	89.58 (5)	C2—C10—C8	119.57 (16)
O—Cu1—N	90.42 (5)	C1—C10—C8	119.94 (16)
O^i—Cu1—N^i	90.42 (5)	C19—C12—C8	121.51 (19)
O—Cu1—N^i	89.58 (5)	C19—C12—H12	119.2
N—Cu1—N^i	180	C8—C12—H12	119.2
C2—O—Cu1	128.62 (11)	C23—C14—C8	119.42 (19)
C1—N—C	115.44 (14)	C23—C14—C18	121.54 (18)
C1—N—Cu1	122.54 (12)	C8—C14—C18	119.03 (18)
C—N—Cu1	121.94 (11)	C7—C15—C9	121.53 (18)
C7—C—C5	118.92 (16)	C7—C15—H15	119.2
C7—C—N	120.13 (15)	C9—C15—H15	119.2
C5—C—N	120.95 (16)	C9—C17—H17A	109.5
N—C1—C10	127.97 (17)	C9—C17—H17B	109.5
N—C1—H1	116.0	H17A—C17—H17B	109.5
C10—C1—H1	116.0	C9—C17—H17C	109.5
O—C2—C10	124.11 (16)	H17A—C17—H17C	109.5
O—C2—C20	116.69 (16)	H17B—C17—H17C	109.5
C10—C2—C20	119.19 (17)	C20—C18—C14	122.24 (18)
C—C5—C6	119.60 (17)	C20—C18—H18	118.9
C—C5—H5	120.2	C14—C18—H18	118.9
C6—C5—H5	120.2	C12—C19—C21	120.4 (2)
C9—C6—C5	122.15 (17)	C12—C19—H19	119.8
C9—C6—H6	118.9	C21—C19—H19	119.8
C5—C6—H6	118.9	C18—C20—C2	120.91 (19)
C15—C7—C	120.38 (17)	C18—C20—H20	119.5
C15—C7—H7	119.8	C2—C20—H20	119.5
C—C7—H7	119.8	C23—C21—C19	120.0 (2)
C12—C8—C14	117.34 (17)	C23—C21—H21	120.0
C12—C8—C10	123.66 (17)	C19—C21—H21	120.0
C14—C8—C10	118.99 (17)	C21—C23—C14	121.4 (2)
C6—C9—C15	117.32 (17)	C21—C23—H23	119.3
C6—C9—C17	121.49 (18)	C14—C23—H23	119.3
C15—C9—C17	121.16 (19)
O^i—Cu1—O—C2	−71 (100)	C20—C2—C10—C8	−3.0 (3)
N—Cu1—O—C2	25.66 (16)	N—C1—C10—C2	11.9 (3)
N^i—Cu1—O—C2	−154.34 (16)	N—C1—C10—C8	−174.99 (17)
O^i—Cu1—N—C1	159.10 (14)	C12—C8—C10—C2	−177.19 (18)
O—Cu1—N—C1	−20.90 (14)	C14—C8—C10—C2	1.7 (3)
N^i—Cu1—N—C1	−22 (100)	C12—C8—C10—C1	9.7 (3)
O^i—Cu1—N—C	−17.40 (13)	C14—C8—C10—C1	−171.42 (16)
O—Cu1—N—C	162.60 (13)	C14—C8—C12—C19	−0.9 (3)
N^i—Cu1—N—C	162 (100)	C10—C8—C12—C19	178.02 (18)
C1—N—C—C7	127.26 (18)	C12—C8—C14—C23	1.0 (3)
Cu1—N—C—C7	−56.0 (2)	C10—C8—C14—C23	−177.99 (17)
C1—N—C—C5	−52.6 (2)	C12—C8—C14—C18	179.69 (18)
Cu1—N—C—C5	124.13 (16)	C10—C8—C14—C18	0.7 (3)
C—N—C1—C10	−176.06 (16)	C—C7—C15—C9	−1.4 (3)
Cu1—N—C1—C10	7.2 (3)	C6—C9—C15—C7	−1.2 (3)
Cu1—O—C2—C10	−15.1 (3)	C17—C9—C15—C7	176.7 (2)
Cu1—O—C2—C20	166.16 (12)	C23—C14—C18—C20	176.8 (2)
C7—C—C5—C6	−2.8 (3)	C8—C14—C18—C20	−1.9 (3)
N—C—C5—C6	177.08 (17)	C8—C12—C19—C21	−0.3 (3)
C—C5—C6—C9	0.2 (3)	C14—C18—C20—C2	0.6 (3)
C5—C—C7—C15	3.4 (3)	O—C2—C20—C18	−179.34 (18)
N—C—C7—C15	−176.46 (17)	C10—C2—C20—C18	1.9 (3)
C5—C6—C9—C15	1.8 (3)	C12—C19—C21—C23	1.5 (4)
C5—C6—C9—C17	−176.09 (19)	C19—C21—C23—C14	−1.5 (4)
O—C2—C10—C1	−8.6 (3)	C8—C14—C23—C21	0.2 (3)
C20—C2—C10—C1	170.11 (16)	C18—C14—C23—C21	−178.5 (2)
O—C2—C10—C8	178.34 (16)

Symmetry code: (i) −x+1, −y, −z.