(Azido-κN)[6-meth­oxy-2-(2-pyridylmethyl­imino­meth­yl)phenolato-κ3N,N′,O1]copper(II)

Sun, X.

doi:10.1107/S1600536807046260

metal-organic compounds

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Volume 64| Part 1| January 2008| Page m33

https://doi.org/10.1107/S1600536807046260

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(Azido-κN)[6-methoxy-2-(2-pyridylmethyliminomethyl)phenolato-κ³N,N′,O¹]copper(II)

Xuan Sun ^a ^*

^aSchool of Chemistry and Chemical Technology, Shandong University, Jinan 250100, People's Republic of China.
^*Correspondence e-mail: sunxuan@sdu.edu.cn

(Received 11 September 2007; accepted 20 September 2007; online 6 December 2007)

The title compound, [Cu(C₁₄H₁₃N₂O₂)(N₃)], is a monomeric neutral complex with one unsymmetrical 6-methoxy-2-(2-pyridylmethyliminomethyl)phenolate Schiff base ligand and one azide ligand. The molecules are connected by a combination of two π–π interactions [centroid–centroid distances 3.359 (3) and 3.378 (2) Å] and one C—H⋯N hydrogen bond into a two-dimensional supramolecular network structure.

Related literature

For related literature, see: Kannappan et al. (2005 ); Li & Zhang (2004 ); Ni & Wang (2007 ); Sun (2005 ); Yang (2005 ).

Experimental

Crystal data

[Cu(C₁₄H₁₃N₂O₂)(N₃)]
M_r = 346.83
Triclinic, $[P \overline 1]$
a = 6.7197 (2) Å
b = 10.2820 (2) Å
c = 10.5549 (5) Å
α = 86.130 (2)°
β = 81.155 (2)°
γ = 76.289 (3)°
V = 699.69 (4) Å³
Z = 2
Mo Kα radiation
μ = 1.58 mm⁻¹
T = 293 (2) K
0.10 × 0.06 × 0.04 mm

Data collection

Bruker APEXII CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 2003 ) T_min = 0.892, T_max = 0.941
11804 measured reflections
3207 independent reflections
2815 reflections with I > 2σ(I)
R_int = 0.020

Refinement

R[F² > 2σ(F²)] = 0.028
wR(F²) = 0.090
S = 0.99
3207 reflections
199 parameters
H-atom parameters constrained
Δρ_max = 0.35 e Å⁻³
Δρ_min = −0.29 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C4—H4⋯N3ⁱ	0.93	2.49	3.189 (2)	132
Symmetry code: (i) x, y-1, z.

Data collection: APEX2 (Bruker, 2004 ); cell refinement: SAINT-Plus (Bruker, 2001 ); data reduction: SAINT-Plus; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: XP (Sheldrick, 1998 ); software used to prepare material for publication: SHELXL97 and XP.

Supporting information

Crystal structure: contains datablocks global, I. DOI: https://doi.org/10.1107/S1600536807046260/si2035sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536807046260/si2035Isup2.hkl

checkCIF report

Comment top

Some Schiff bases can be potential employed as in-plane ligands which usually exhibit beautiful supramolecular structures via π-π interactions (Kannappan et al., 2005; Li & Zhang, 2004; Yang, 2005). In addtion, the complexes based on these Schiff base ligands can form various hydrogen bonds through reasonable design and the introduction of suitable assistant groups (Sun, 2005).

The geometry and labelling scheme for the crystal structure of the title complex are depicted in Figure 1. The title compound is a monomeric neutral complex with one tridentate unsymmetric Schiff base 6-Methoxy-2-(2-pyridylmethyliminomethyl)phenol and one azide group, which are similar to its derivatives [Cu(C₁₄H₁₃N₂O₂)(Cl)] and [Cu(C₁₄H₁₃N₂O₂)(Br)] (Kannappan et al., 2005). The Cu(II) center of the title complex is coordinated by one pyridine and one imide nitrogen atoms and one phenoxo oxygen atom from Schiff base ligand and one terminal nitrogen atom from azide group, yielding a distorted square-planar coordinaton environment. All atoms in the title complex except N2 and N3 form a plane with the largest deviation value of 0.0514 (16) Å from the mean plane.

The Cu1—O1 bond distance is 1.9062 (14) Å. The Cu—N_pyridine, Cu—N_imine and Cu—N_azide bond lengths are 2.0106 (16), 1.9315 (16) and 1.9504 (19) Å, which are similar to those in complexes [Cu(C₁₄H₁₃N₂O₂)(Cl)] and [Cu(C₁₄H₁₃N₂O₂)(Br)]. The bond angles O1—Cu1—N4 (175.78 (5) Å) and N1—Cu1—N5 (175.35 (7) Å) are nearly linear. The chelate bite angles for the five and six-membered rings formed by the Schiff base are 82.20 (7) ° and 93.59 (6) °, which are also similar to those in the Cl and Br complexes reported by Kannappan et al., (2005). The imide bond length (1.290 (3) Å for C7—N5) is slightly longer than that in ligand 6-Methoxy-2-(2-pyridylmethyliminomethyl)phenol (1.278 (2) Å) (Ni et al., 2007). The N—N bond distances are 1.181 (3) Å for N1—N2 and 1.147 (3) Å for N2—N3. The N1—N2—N3 bond angle is 176.4 (2) ° and the Cu1—N1—N2 bond angle is 122.36 (17) °.

The title compound shows various non-covalent intermolecular interactions and forms a very interesting two-dimensional supramolecular network structure (Figure 2). The units of the title complexes connect each other by two different π-π interactions with inter-unit distances 3.359 (3) Å and 3.378 (2) Å, resulting in one-dimensional supramolecular substructures. These substructures are linked by the C—H···N hydrogen bonds between the pyridine carbon atom and uncoordinated terminal azide nitrogen atom into a beautiful two-dimensional supramolecular structure.

Related literature top

For related literature, see: Kannappan et al. (2005); Li & Zhang (2004); Ni & Wang (2007); Sun (2005); Yang (2005).

Experimental top

The Schiff base 6-Methoxy-2-(2-pyridylmethyliminomethyl)phenol (HL) was synthesized according to literature (Ni et al., 2007). The title complex was prepared as following: aquaous and methanol solution (6 ml, MeOH/H₂O = 2:1 v/v) of NaN₃ (52 mg, 0.8 mmol) was added into a MeOH and aquaous solution (20 ml, MeOH/H₂O = 4:1 v/v) containing the HL ligand (48 mg, 0.2 mmol) and CuCl₂.2H₂O (34 mg, 0.2 mmol). The mixture was rapidly filtered and the resulting solution was kept at room temperature for about six hours, giving rise a to brown product. Yield: 60%. Elemental analysis [found (calculated)] for CuC₁₄H₁₃N₅O₂: C 48.35 (48.48), H 3.70 (3.78), N 20.12% (20.19%).

Structure description top

For related literature, see: Kannappan et al. (2005); Li & Zhang (2004); Ni & Wang (2007); Sun (2005); Yang (2005).

Computing details top

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, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: XP (Sheldrick, 1998); software used to prepare material for publication: SHELXL97 (Sheldrick, 1997) and XP (Sheldrick, 1998).

Figures top

Fig. 1. A view of (I) with the unique atom-labelling scheme. Displacement ellipsoids are drawn at the 30% probability level, solvate water molecules and all H atoms bonded to C atoms are omitted.

Fig. 2. A stereoview of part of the crystal structure of (I), showing the two-dimensional supramolecular structure. For the sake of clarity, H atoms bonded to C atoms and not involved in the motif shown have been omitted. Atoms marked with an asterisk (*), a hash (#) or a dollar sign ($) are at the symmetry positions (-x + 2, -y, -z + 1), (-x + 1, -y, -z + 1), (x, y + 1, z) and (x, y + 1, z), respectively.

(Azido-κN)[6-methoxy-2-(2-pyridylmethyliminomethyl)phenolato- κ³N,N',O¹]copper(II) top

Crystal data top

[Cu(C₁₄H₁₃N₂O₂)(N₃)]	Z = 2
M_r = 346.83	F(000) = 354
Triclinic, P1	D_x = 1.646 Mg m⁻³
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 6.7197 (2) Å	Cell parameters from 3207 reflections
b = 10.2820 (2) Å	θ = 2.0–27.5°
c = 10.5549 (5) Å	µ = 1.58 mm⁻¹
α = 86.130 (2)°	T = 293 K
β = 81.155 (2)°	Tiny block, brown
γ = 76.289 (3)°	0.10 × 0.06 × 0.04 mm
V = 699.69 (4) Å³

Data collection top

Bruker APEXII CCD area-detector diffractometer	3207 independent reflections
Radiation source: fine-focus sealed tube	2815 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.020
φ and ω scans	θ_max = 27.5°, θ_min = 2.0°
Absorption correction: multi-scan (SADABS; Sheldrick, 2003)	h = −8→8
T_min = 0.892, T_max = 0.941	k = −13→13
11804 measured reflections	l = −13→13

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.028	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.090	H-atom parameters constrained
S = 0.99	w = 1/[σ²(F_o²) + (0.066P)² + 0.0216P] where P = (F_o² + 2F_c²)/3
3207 reflections	(Δ/σ)_max = 0.001
199 parameters	Δρ_max = 0.35 e Å⁻³
0 restraints	Δρ_min = −0.29 e Å⁻³

Crystal data top

[Cu(C₁₄H₁₃N₂O₂)(N₃)]	γ = 76.289 (3)°
M_r = 346.83	V = 699.69 (4) Å³
Triclinic, P1	Z = 2
a = 6.7197 (2) Å	Mo Kα radiation
b = 10.2820 (2) Å	µ = 1.58 mm⁻¹
c = 10.5549 (5) Å	T = 293 K
α = 86.130 (2)°	0.10 × 0.06 × 0.04 mm
β = 81.155 (2)°

Data collection top

Bruker APEXII CCD area-detector diffractometer	3207 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 2003)	2815 reflections with I > 2σ(I)
T_min = 0.892, T_max = 0.941	R_int = 0.020
11804 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.028	0 restraints
wR(F²) = 0.090	H-atom parameters constrained
S = 0.99	Δρ_max = 0.35 e Å⁻³
3207 reflections	Δρ_min = −0.29 e Å⁻³
199 parameters

Special details top

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

	x	y	z	U_iso*/U_eq
Cu1	0.71363 (3)	0.01027 (2)	0.64642 (2)	0.03501 (10)
O1	0.6949 (2)	0.15473 (13)	0.52246 (13)	0.0419 (3)
O2	0.6515 (3)	0.38174 (15)	0.38914 (16)	0.0527 (4)
N1	0.6386 (4)	0.1355 (2)	0.78607 (19)	0.0566 (5)
N2	0.7302 (3)	0.21856 (17)	0.79457 (17)	0.0483 (4)
N3	0.8155 (4)	0.2994 (2)	0.8096 (3)	0.0735 (7)
N4	0.7379 (2)	−0.15134 (16)	0.76640 (16)	0.0373 (3)
N5	0.7842 (2)	−0.12500 (16)	0.51834 (16)	0.0357 (3)
C5	0.7893 (3)	−0.26937 (19)	0.7095 (2)	0.0380 (4)
C8	0.7789 (3)	0.0241 (2)	0.33149 (19)	0.0381 (4)
C12	0.7057 (3)	0.2671 (2)	0.3210 (2)	0.0411 (4)
C13	0.7266 (3)	0.14646 (19)	0.39683 (19)	0.0369 (4)
C1	0.7074 (3)	−0.1514 (2)	0.8959 (2)	0.0459 (5)
H1	0.6707	−0.0697	0.9363	0.055*
C2	0.7285 (4)	−0.2665 (3)	0.9697 (2)	0.0553 (6)
H2	0.7077	−0.2630	1.0587	0.066*
C3	0.7806 (4)	−0.3881 (2)	0.9112 (2)	0.0530 (6)
H3	0.7940	−0.4678	0.9599	0.064*
C4	0.8128 (3)	−0.3895 (2)	0.7786 (2)	0.0472 (5)
H4	0.8498	−0.4703	0.7366	0.057*
C7	0.8033 (3)	−0.1038 (2)	0.3957 (2)	0.0399 (4)
H7	0.8357	−0.1784	0.3448	0.048*
C9	0.8117 (3)	0.0253 (2)	0.1950 (2)	0.0467 (5)
H9	0.8470	−0.0553	0.1528	0.056*
C10	0.7921 (3)	0.1424 (2)	0.1258 (2)	0.0511 (5)
H10	0.8144	0.1418	0.0367	0.061*
C11	0.7386 (3)	0.2640 (2)	0.1881 (2)	0.0460 (5)
H11	0.7248	0.3439	0.1399	0.055*
C6	0.8206 (3)	−0.26431 (19)	0.5655 (2)	0.0426 (4)
H6A	0.9607	−0.3110	0.5335	0.051*
H6B	0.7257	−0.3085	0.5347	0.051*
C14	0.6187 (4)	0.5071 (2)	0.3204 (3)	0.0576 (6)
H14A	0.5820	0.5784	0.3799	0.086*
H14B	0.5087	0.5137	0.2703	0.086*
H14C	0.7431	0.5138	0.2646	0.086*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Cu1	0.03917 (16)	0.03307 (14)	0.03272 (15)	−0.00818 (10)	−0.00430 (10)	−0.00288 (9)
O1	0.0541 (8)	0.0374 (7)	0.0338 (7)	−0.0092 (6)	−0.0065 (6)	−0.0025 (5)
O2	0.0669 (10)	0.0411 (8)	0.0486 (9)	−0.0096 (7)	−0.0097 (8)	0.0030 (7)
N1	0.0808 (14)	0.0462 (10)	0.0410 (11)	−0.0179 (10)	0.0068 (10)	−0.0107 (8)
N2	0.0719 (12)	0.0295 (8)	0.0380 (10)	0.0006 (8)	−0.0104 (8)	0.0000 (7)
N3	0.1041 (19)	0.0387 (11)	0.0809 (17)	−0.0149 (11)	−0.0245 (14)	−0.0045 (10)
N4	0.0354 (8)	0.0380 (8)	0.0394 (9)	−0.0103 (6)	−0.0063 (7)	0.0002 (7)
N5	0.0347 (8)	0.0356 (8)	0.0373 (9)	−0.0081 (6)	−0.0056 (7)	−0.0028 (6)
C5	0.0308 (9)	0.0383 (9)	0.0460 (11)	−0.0102 (7)	−0.0071 (8)	0.0020 (8)
C8	0.0348 (9)	0.0458 (10)	0.0343 (10)	−0.0103 (8)	−0.0047 (8)	−0.0024 (8)
C12	0.0353 (10)	0.0441 (11)	0.0444 (11)	−0.0095 (8)	−0.0083 (8)	0.0021 (8)
C13	0.0306 (9)	0.0443 (10)	0.0364 (11)	−0.0092 (7)	−0.0063 (7)	0.0007 (8)
C1	0.0487 (12)	0.0496 (12)	0.0393 (12)	−0.0124 (9)	−0.0057 (9)	0.0013 (9)
C2	0.0554 (13)	0.0672 (15)	0.0434 (13)	−0.0178 (11)	−0.0073 (10)	0.0111 (11)
C3	0.0510 (12)	0.0501 (12)	0.0586 (15)	−0.0169 (10)	−0.0101 (10)	0.0175 (10)
C4	0.0432 (11)	0.0391 (10)	0.0608 (14)	−0.0130 (8)	−0.0094 (10)	0.0055 (9)
C7	0.0393 (10)	0.0425 (10)	0.0387 (11)	−0.0090 (8)	−0.0040 (8)	−0.0108 (8)
C9	0.0495 (12)	0.0569 (12)	0.0345 (11)	−0.0123 (9)	−0.0060 (9)	−0.0072 (9)
C10	0.0501 (12)	0.0724 (15)	0.0308 (11)	−0.0144 (11)	−0.0072 (9)	0.0029 (10)
C11	0.0412 (11)	0.0548 (12)	0.0432 (12)	−0.0140 (9)	−0.0107 (9)	0.0108 (9)
C6	0.0483 (11)	0.0344 (9)	0.0454 (12)	−0.0087 (8)	−0.0068 (9)	−0.0056 (8)
C14	0.0596 (14)	0.0430 (12)	0.0701 (16)	−0.0115 (10)	−0.0144 (12)	0.0093 (11)

Geometric parameters (Å, º) top

Cu1—O1	1.9062 (14)	C7—C8	1.423 (3)
Cu1—N1	1.9504 (19)	C7—H7	0.93
Cu1—N4	2.0106 (16)	C13—C8	1.419 (3)
Cu1—N5	1.9315 (16)	C13—C12	1.420 (3)
N1—N2	1.181 (3)	C5—C6	1.500 (3)
N2—N3	1.147 (3)	C1—C2	1.364 (3)
O1—C13	1.316 (2)	C1—H1	0.93
O2—C12	1.368 (3)	C3—C2	1.377 (4)
O2—C14	1.423 (3)	C3—H3	0.93
C11—C12	1.387 (3)	C9—C10	1.355 (3)
C11—C10	1.397 (3)	C9—C8	1.423 (3)
C11—H11	0.93	C9—H9	0.93
N5—C7	1.290 (3)	C6—H6A	0.97
N5—C6	1.461 (2)	C6—H6B	0.97
N4—C5	1.338 (3)	C14—H14A	0.96
N4—C1	1.351 (3)	C14—H14B	0.96
C4—C3	1.384 (3)	C14—H14C	0.96
C4—C5	1.380 (3)	C2—H2	0.93
C4—H4	0.93	C10—H10	0.93

O1—Cu1—N1	90.95 (7)	C4—C5—C6	121.54 (18)
O1—Cu1—N5	93.59 (6)	N4—C1—C2	122.5 (2)
N1—Cu1—N5	175.35 (7)	N4—C1—H1	118.8
O1—Cu1—N4	175.78 (5)	C2—C1—H1	118.8
N4—Cu1—N5	82.20 (7)	C4—C3—C2	118.7 (2)
N1—Cu1—N4	93.26 (8)	C4—C3—H3	120.6
N1—N2—N3	176.4 (2)	C2—C3—H3	120.6
C13—O1—Cu1	127.21 (13)	C10—C9—C8	120.8 (2)
C12—O2—C14	118.41 (18)	C10—C9—H9	119.6
C12—C11—C10	120.8 (2)	C8—C9—H9	119.6
C12—C11—H11	119.6	N2—N1—Cu1	122.36 (17)
C10—C11—H11	119.6	N5—C6—C5	109.75 (16)
C7—N5—C6	117.27 (17)	N5—C6—H6A	109.7
C7—N5—Cu1	126.15 (14)	C5—C6—H6A	109.7
C6—N5—Cu1	116.57 (13)	N5—C6—H6B	109.7
C5—N4—C1	118.20 (18)	C5—C6—H6B	109.7
C5—N4—Cu1	115.20 (14)	H6A—C6—H6B	108.2
C1—N4—Cu1	126.61 (14)	C9—C8—C13	120.07 (19)
C3—C4—C5	119.0 (2)	C9—C8—C7	116.64 (19)
C3—C4—H4	120.5	C13—C8—C7	123.29 (19)
C5—C4—H4	120.5	O2—C14—H14A	109.5
N5—C7—C8	125.60 (18)	O2—C14—H14B	109.5
N5—C7—H7	117.2	H14A—C14—H14B	109.5
C8—C7—H7	117.2	O2—C14—H14C	109.5
O1—C13—C8	124.15 (18)	H14A—C14—H14C	109.5
O1—C13—C12	118.36 (17)	H14B—C14—H14C	109.5
C8—C13—C12	117.49 (18)	C1—C2—C3	119.4 (2)
O2—C12—C11	124.42 (19)	C1—C2—H2	120.3
O2—C12—C13	114.87 (18)	C3—C2—H2	120.3
C11—C12—C13	120.70 (19)	C9—C10—C11	120.1 (2)
N4—C5—C4	122.2 (2)	C9—C10—H10	119.9
N4—C5—C6	116.27 (17)	C11—C10—H10	119.9

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C4—H4···N3ⁱ	0.93	2.49	3.189 (2)	132

Symmetry code: (i) x, y−1, z.

Experimental details

Crystal data
Chemical formula	[Cu(C₁₄H₁₃N₂O₂)(N₃)]
M_r	346.83
Crystal system, space group	Triclinic, P1
Temperature (K)	293
a, b, c (Å)	6.7197 (2), 10.2820 (2), 10.5549 (5)
α, β, γ (°)	86.130 (2), 81.155 (2), 76.289 (3)
V (Å³)	699.69 (4)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	1.58
Crystal size (mm)	0.10 × 0.06 × 0.04

Data collection
Diffractometer	Bruker APEXII CCD area-detector
Absorption correction	Multi-scan (SADABS; Sheldrick, 2003)
T_min, T_max	0.892, 0.941
No. of measured, independent and observed [I > 2σ(I)] reflections	11804, 3207, 2815
R_int	0.020
(sin θ/λ)_max (Å⁻¹)	0.649

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.028, 0.090, 0.99
No. of reflections	3207
No. of parameters	199
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.35, −0.29

Computer programs: APEX2 (Bruker, 2004), SAINT-Plus (Bruker, 2001), SHELXS97 (Sheldrick, 1997), SHELXL97 (Sheldrick, 1997) and XP (Sheldrick, 1998).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C4—H4···N3ⁱ	0.930	2.492	3.189 (2)	131.92

Symmetry code: (i) x, y−1, z.

Acknowledgements

This work was supported by the Natural Science Foundation of China.

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