catena-Poly[[[2-(2-chlorophenoxy)-N′-(2-oxidobenzylidene-κO)aceto­hydrazidato-κ²N′,O]copper(II)]-μ-morpholine-κ²N:O]

In the title compound, {[Cu(C₁₅H₁₁ClN₂O₃)(C₄H₉NO)]_n, the Cu^II cation has square-pyramidal geometry. The morpholine ligand serves as a bridge to link two symmetry-related metal atoms, resulting in an infinite chain structure along the a axis. Adjacent chains are extended into a two-dimensional layered structure via hydrogen bonds formed between morpholine and amide N atoms [N—H...N = 2.971 (3) Å].

S1. Comment

Morpholine and its derivatives are an important class of ligand for the construction of inorganic-organic hybrids. They act as templates, charge-compensating cations or space-filling agents (Ritchie et al., 2008; Zhu et al., 2009; Li et al., 2010; Thiel et al., 2010). This strategy appears to afford primitive control over the dimensionality of the solid through manipulation of the steric requirements and denticity of the ligand. On the other hand, morpholine, with its inherent coordination and hydrogen-bonding donor functionalities, is a good ligand for the construction of supramolecular architectures (Weinberger et al., 1998). The chemistry of acylhydrazone Schiff bases, including salicylaldehyde–acylhydrazone Schiff bases, has been extensively investigated by many authors in the synthesis of mono-, di- and polynuclear transition metal complexes (Amirnasr et al., 2001; Lin & Feng, 2005; Yuan et al., 2005; Lian et al., 2008; Chen et al., 2009; Zhu et al., 2009). The intense interest in these compounds is driven not only by their intriguing architectures, but also by their wide spectrum of biological activities, such as antibacterial and antifungal properties, and their potential applications as functional materials (Koh et al., 1998; Ainscough et al., 1999). The tridentate ligand (2-chlorophenoxy)-N'-(2-hydroxybenzylidene)acetohydrazide (H₃L), containing ONO donors, is a good candidate for the construction of supramolecular architectures, but the study of this ligand has been little explored. Several compounds based on N-phenylacetylsalicylhydrazide derivatives have been reported (Li & Liu, 2004; Sun et al., 2005; Chen & Liu, 2006; Zhang et al., 2009). Most of these compounds are mononuclear. In these compounds, the secondary ligand, such as morpholine, plays an important role in the self-assembly process. Considering all the above-mentioned strands of interest, we considered that the simultaneous use of the morpholine ligand and H₃L would contribute to the formation of various architectures and help chemists understand the process of self-assembly. In the present work, we obtained the title Cu^II Schiff base complex, (I), and report its synthesis and crystal structure.

Complex (I) consists of the tridentate ligand and Cu^II in a 1:1 ratio. The Cu^II cation is in a square-pyramidal geometry, coordinated by a dinegative tridentate ligand through one phenoxy O atom, one imine N atom, one amide O atom and one N atom from the morpholine molecule in the basal plane, and by one O atom from a symmetry-related morpholine molecule at (1/2 + x, y, 1/2 - z) occupying the apical site. The coordination configuration of the metal centre is similar to those found in copper analogues (Ranford et al., 1998; Wu et al., 2007). In other comparable structures, the copper cations are in a square-planar geometry (Lian et al., 2008). The Cu^II cation lies approximately in the least-squares plane defined by the four donor atoms, with a slight deviation of 0.0004 Å (plane equation: -0.8660x + 0.4846y - 0.1232z = -4.9818). The bond lengths between Cu^II and the phenolic O, imine N and deprotonated amide O atoms are similar to those found in the metal complexes of special compartmental ligands (Lu et al., 2003; Lian et al., 2008). The apical Cu—O distance is considerably longer than the basal ones, but shorter than values reported for other related copper complexes (Wu et al., 2007). The angles subtended at the Cu^II cation by cis pairs of ligating atoms cover the range 80.90 (1)–94.65 (1)°, and the angles subtended by the trans pairs are 165.89 (1) and 173.05 (9)° [For which?], respectively. The dinegative ligand coordinates to the metal cation via the phenolate O atom, the imine N atom and the deprotonated amide O atom, foming five-and six-membered chelate rings. The C—O distances are consistent with the location of the H atoms deduced from difference maps, which indicate that the ligand carries a charge of -2, satisfying the charge-balance requirement.

In (I), interconnection of Cu^II cations and H₃L and morpholine ligands leads to an infinite chain structure along the a axis. The morpholine ligand coordinates to two symmetry-related Cu^II cations, one at (x - 1/2 , y, -z + 3/2), in a µ₂ mode. The separation between the symmetry-related Cu^II cations within the chain thus formed is 6.0638 (7) Å. Most comparable compounds based on a salicylaldehyde–acylhydrazone Schiff base are mononuclear, although several dinuclear copper complexes have been reported (Wu et al., 2007; Chen et al., 2009; Lian et al., 2008; Ranford et al., 1998). Interestingly, in comparable compounds of the form [(L₂)Cu₂(µ-N—N)](ClO₄)₂, where N—N = piperazine or 4,4'-bipyridine], the 4,4'-bipyridine and piperazine ligands bridge the copper Schiff base complexes, forming descrete dimers (Rigamonti et al., 2011). In our experiments, 4,4'-bipyridine or piperazine ligands were employed to take the place of the morpholine ligand, but we did not obtain the expected product. We think that the morpholine ligand in the chair configuration found here matches well with the steric requirements and denticity.

In the packing structure of (I), the metal complexes align in a linear mode and adjacent chains interact with each other via hydrogen bonds formed between morpholine and amide N atoms [N3—H3···N2ⁱ = 2.971 (3) Å; symmetry code: (i) -x + 1/2, y + 1/2, z] to generate two-dimensional grid sheets. In the comparable Mn^II analogues, the hexacoordinate metal centres are linked via N—H···O and O—H···O hydrogen bonds to form a one-dimensional chain structure (Li & Liu, 2004). In [Cu₂(L)₂(H₂O)₂](H₂O)₁₂ (where L = salicylaldehyde-2-sulfobenzoylhydrazone), dodecameric water clusters are formed which are linked to form a layer along the a axis by intermolecular hydrogen-bonding interactions between the O atoms of the SO₃ groups and the solvent water molecules in the three-dimensional network (Wu et al., 2007).

In summary, a copper complex derived from an acylhydrazone Schiff base ligand has been prepared. In the crystal structure, the metal complexes are bridged by morpholine ligands into an infinite chain. Intermolecular self-complementary hydrogen bonds formed between the N-bound H atom on the morpholine ligand and the H₃L ligands are observed.

Related literature

For related literature, see: Ainscough et al. (1999); Amirnasr et al. (2001); Chen & Liu (2006); Chen et al. (2009); Koh et al. (1998); Li & Liu (2004); Li et al. (2010); Lian et al. (2008); Lin & Feng (2005); Lu et al. (2003); Ranford et al. (1998); Rigamonti et al. (2011); Ritchie et al. (2008); Sun et al. (2005); Thiel et al. (2010); Weinberger et al. (1998); Wu et al. (2007); Yuan et al. (2005); Zhang et al. (2009); Zhu et al. (2009).

S2. Experimental

A mixture of 2-chlorophenoxy-2-hydroxybenzylidene acetohydrazide (H₃L) (0.031 g, 0.1 mmol), Cu(CH₃COO)₂ (0.018 g, 0.1 mmol), morpholine (0.1 g, 1.15 mmol), CH₃OH (10 ml) and DMF (2 ml) was stirred for about 120 min. The resulting solution was left at room temperature for a few days, and green single crystals of (I) (about 78%, based on Cu input) were recovered by vacuum filtration and dried in air. Elemental analysis, calulated for (I): C 50.33, H 4.45, N 9.27%; found: C 50.31, H 4.47, N 9.31%.

S3. Refinement

H atoms were positioned geometrically, with C—H = 0.93–0.97 Å or N—H = 0.91 Å, and refined as riding, with U_iso(H) = 1.2U_eq(C,N). [Distances have been amended to match CIF tables - please confirm.]

Computing details

Data collection: SMART (Bruker, 2007); cell refinement: SMART (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg, 2010); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures

	Fig. 1. The molecular structure of (I), showing the atom-numbering scheme. Displacement ellipsoids are drawn at the 50% probability level. [Symmetry codes: (i) 1/2 + x, y, 3/2 - z; (ii) -1/2 + x, y, 3/2 - z.]
	Fig. 2. [Please provide missing caption.]

catena-Poly[[[2-(2-chlorophenoxy)-N'-(2-oxidobenzylidene-κO)acetohydrazidato-κ²N',O]copper(II)]-µ-morpholine-κ²N:O]

Crystal data

[Cu(C15H11ClN2O3)(C4H9NO)]	F(000) = 1864
Mr = 453.37	Dx = 1.535 Mg m^−3
Orthorhombic, Pbca	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ac 2ab	Cell parameters from 14071 reflections
a = 12.1097 (14) Å	θ = 12–18°
b = 12.7228 (15) Å	µ = 1.28 mm^−1
c = 25.460 (3) Å	T = 298 K
V = 3922.5 (8) Å^3	Block, green
Z = 8	0.50 × 0.40 × 0.20 mm

Data collection

Bruker SMART CCD area-detector diffractometer	4467 independent reflections
Radiation source: fine-focus sealed tube	2914 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.055
Detector resolution: 8.33 pixels mm^-1	θmax = 27.5°, θmin = 1.6°
ϕ and ω scans	h = −15→15
Absorption correction: multi-scan (SADABS; Bruker, 2007)	k = −16→12
Tmin = 0.546, Tmax = 0.774	l = −32→33
14071 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)] = 0.042	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.119	H-atom parameters constrained
S = 1.01	w = 1/[σ^2(Fo^2) + (0.0583P)^2 + 0.0542P] where P = (Fo^2 + 2Fc^2)/3
4467 reflections	(Δ/σ)max = 0.001
253 parameters	Δρmax = 0.47 e Å^−3
0 restraints	Δρmin = −0.40 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	0.33070 (3)	0.14424 (3)	0.743508 (13)	0.02818 (13)
Cl1	0.29359 (14)	0.24731 (10)	0.95875 (5)	0.0944 (5)
O1	0.3587 (2)	0.16286 (17)	0.67086 (9)	0.0418 (6)
O2	0.2266 (2)	0.05254 (19)	0.91314 (9)	0.0460 (6)
O3	0.28663 (19)	0.11455 (17)	0.81582 (8)	0.0356 (5)
O4	0.64883 (17)	0.22791 (18)	0.76452 (8)	0.0370 (5)
N1	0.2720 (2)	0.00459 (19)	0.73382 (9)	0.0301 (6)
N2	0.2273 (2)	−0.04121 (19)	0.77925 (10)	0.0335 (6)
N3	0.4178 (2)	0.27242 (19)	0.76592 (9)	0.0298 (6)
H3	0.3671	0.3230	0.7734	0.036*
C1	0.3148 (2)	−0.0135 (3)	0.64183 (12)	0.0335 (7)
C2	0.3150 (3)	−0.0851 (3)	0.59935 (14)	0.0468 (9)
H2	0.2897	−0.1533	0.6046	0.056*
C3	0.3516 (3)	−0.0560 (3)	0.55069 (14)	0.0561 (11)
H3A	0.3501	−0.1036	0.5230	0.067*
C4	0.3908 (4)	0.0445 (3)	0.54306 (14)	0.0573 (11)
H4	0.4163	0.0644	0.5101	0.069*
C5	0.3925 (3)	0.1155 (3)	0.58357 (14)	0.0499 (10)
H5	0.4195	0.1827	0.5773	0.060*
C6	0.3550 (2)	0.0901 (3)	0.63397 (12)	0.0347 (7)
C7	0.2721 (2)	−0.0502 (2)	0.69113 (12)	0.0316 (7)
H7	0.2427	−0.1177	0.6924	0.038*
C8	0.2389 (3)	0.0252 (2)	0.81830 (12)	0.0321 (7)
C9	0.1875 (3)	−0.0076 (3)	0.87037 (12)	0.0439 (9)
H9A	0.1079	−0.0002	0.8681	0.053*
H9B	0.2037	−0.0812	0.8767	0.053*
C10	0.3377 (3)	0.0540 (3)	0.92159 (12)	0.0449 (9)
C11	0.4091 (4)	−0.0270 (4)	0.90935 (16)	0.0646 (12)
H11	0.3815	−0.0876	0.8937	0.078*
C12	0.5202 (4)	−0.0198 (5)	0.91986 (18)	0.0833 (16)
H12	0.5669	−0.0751	0.9111	0.100*
C13	0.5618 (5)	0.0672 (6)	0.9428 (2)	0.095 (2)
H13	0.6370	0.0714	0.9499	0.114*
C14	0.4937 (5)	0.1500 (5)	0.95590 (17)	0.0858 (17)
H14	0.5226	0.2098	0.9718	0.103*
C15	0.3802 (4)	0.1433 (3)	0.94509 (14)	0.0606 (11)
C16	0.4930 (3)	0.3186 (2)	0.72579 (13)	0.0359 (7)
H16A	0.5193	0.3865	0.7377	0.043*
H16B	0.4533	0.3287	0.6931	0.043*
C17	0.5892 (3)	0.2462 (3)	0.71704 (13)	0.0387 (8)
H17A	0.5626	0.1797	0.7033	0.046*
H17B	0.6384	0.2768	0.6911	0.046*
C18	0.5780 (3)	0.1840 (3)	0.80407 (12)	0.0360 (7)
H18A	0.6198	0.1733	0.8361	0.043*
H18B	0.5509	0.1162	0.7924	0.043*
C19	0.4815 (2)	0.2556 (3)	0.81505 (12)	0.0360 (7)
H19A	0.4343	0.2244	0.8415	0.043*
H19B	0.5080	0.3225	0.8283	0.043*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Cu1	0.0283 (2)	0.0265 (2)	0.02973 (19)	−0.00286 (16)	−0.00068 (16)	0.00118 (15)
Cl1	0.1485 (13)	0.0552 (7)	0.0795 (8)	−0.0184 (8)	0.0088 (8)	−0.0104 (6)
O1	0.0531 (15)	0.0384 (13)	0.0339 (12)	−0.0117 (11)	0.0009 (11)	0.0003 (10)
O2	0.0480 (15)	0.0575 (16)	0.0326 (12)	−0.0048 (13)	0.0075 (11)	−0.0057 (11)
O3	0.0420 (13)	0.0337 (12)	0.0310 (11)	−0.0112 (10)	−0.0032 (10)	0.0000 (9)
O4	0.0262 (11)	0.0424 (13)	0.0425 (12)	0.0022 (10)	0.0018 (10)	0.0033 (10)
N1	0.0298 (14)	0.0299 (14)	0.0305 (13)	−0.0006 (11)	−0.0002 (11)	0.0007 (11)
N2	0.0362 (15)	0.0302 (14)	0.0341 (14)	−0.0076 (12)	0.0021 (12)	0.0014 (11)
N3	0.0271 (13)	0.0256 (13)	0.0367 (13)	0.0041 (11)	0.0010 (11)	−0.0005 (11)
C1	0.0309 (17)	0.0386 (18)	0.0310 (16)	0.0068 (14)	−0.0017 (13)	−0.0035 (14)
C2	0.056 (2)	0.041 (2)	0.0426 (19)	0.0101 (17)	−0.0067 (17)	−0.0097 (16)
C3	0.074 (3)	0.058 (3)	0.0364 (19)	0.018 (2)	0.0015 (19)	−0.0128 (18)
C4	0.075 (3)	0.062 (3)	0.0351 (19)	0.019 (2)	0.012 (2)	0.0034 (18)
C5	0.058 (2)	0.052 (2)	0.0404 (19)	0.0052 (19)	0.0088 (18)	0.0061 (17)
C6	0.0292 (17)	0.046 (2)	0.0284 (15)	0.0065 (15)	−0.0003 (13)	−0.0001 (14)
C7	0.0265 (16)	0.0283 (17)	0.0399 (17)	0.0000 (13)	−0.0038 (14)	−0.0036 (13)
C8	0.0282 (16)	0.0330 (18)	0.0351 (16)	−0.0013 (14)	−0.0013 (14)	0.0038 (13)
C9	0.048 (2)	0.051 (2)	0.0329 (17)	−0.0147 (17)	0.0001 (15)	0.0057 (16)
C10	0.050 (2)	0.059 (2)	0.0258 (16)	−0.008 (2)	0.0001 (16)	0.0064 (15)
C11	0.058 (3)	0.084 (3)	0.051 (2)	0.005 (2)	−0.002 (2)	0.003 (2)
C12	0.054 (3)	0.135 (5)	0.061 (3)	0.010 (3)	−0.001 (2)	0.021 (3)
C13	0.062 (3)	0.158 (6)	0.065 (3)	−0.022 (4)	−0.015 (3)	0.034 (4)
C14	0.101 (4)	0.107 (4)	0.049 (2)	−0.055 (4)	−0.021 (3)	0.012 (3)
C15	0.080 (3)	0.068 (3)	0.0340 (19)	−0.022 (2)	−0.001 (2)	0.0062 (19)
C16	0.0284 (16)	0.0289 (17)	0.0504 (18)	−0.0030 (14)	−0.0028 (15)	0.0051 (14)
C17	0.0305 (17)	0.045 (2)	0.0405 (18)	0.0016 (15)	0.0012 (15)	0.0074 (15)
C18	0.0295 (17)	0.0421 (19)	0.0364 (17)	0.0003 (15)	−0.0018 (14)	0.0062 (14)
C19	0.0300 (17)	0.0393 (19)	0.0385 (17)	−0.0026 (14)	0.0024 (14)	−0.0060 (14)

Geometric parameters (Å, º)

Cu1—O1	1.895 (2)	C5—C6	1.399 (4)
Cu1—N1	1.929 (3)	C5—H5	0.9300
Cu1—O3	1.954 (2)	C7—H7	0.9300
Cu1—N3	2.025 (2)	C8—C9	1.523 (4)
Cl1—C15	1.724 (5)	C9—H9A	0.9700
O1—C6	1.319 (4)	C9—H9B	0.9700
O2—C10	1.362 (4)	C10—C11	1.381 (5)
O2—C9	1.413 (4)	C10—C15	1.383 (5)
O3—C8	1.277 (4)	C11—C12	1.375 (6)
O4—C17	1.427 (4)	C11—H11	0.9300
O4—C18	1.436 (4)	C12—C13	1.350 (7)
N1—C7	1.291 (4)	C12—H12	0.9300
N1—N2	1.404 (3)	C13—C14	1.378 (8)
N2—C8	1.312 (4)	C13—H13	0.9300
N3—C19	1.485 (4)	C14—C15	1.404 (7)
N3—C16	1.489 (4)	C14—H14	0.9300
N3—H3	0.9100	C16—C17	1.502 (4)
C1—C2	1.414 (4)	C16—H16A	0.9700
C1—C6	1.420 (5)	C16—H16B	0.9700
C1—C7	1.435 (4)	C17—H17A	0.9700
C2—C3	1.367 (5)	C17—H17B	0.9700
C2—H2	0.9300	C18—C19	1.508 (4)
C3—C4	1.378 (5)	C18—H18A	0.9700
C3—H3A	0.9300	C18—H18B	0.9700
C4—C5	1.371 (5)	C19—H19A	0.9700
C4—H4	0.9300	C19—H19B	0.9700
O1—Cu1—N1	93.22 (10)	C8—C9—H9A	109.1
O1—Cu1—O3	173.05 (9)	O2—C9—H9B	109.1
N1—Cu1—O3	80.90 (10)	C8—C9—H9B	109.1
O1—Cu1—N3	94.65 (10)	H9A—C9—H9B	107.8
N1—Cu1—N3	165.89 (10)	O2—C10—C11	124.9 (4)
O3—Cu1—N3	91.86 (9)	O2—C10—C15	116.6 (4)
C6—O1—Cu1	127.0 (2)	C11—C10—C15	118.5 (4)
C10—O2—C9	117.4 (3)	C12—C11—C10	121.3 (5)
C8—O3—Cu1	110.02 (18)	C12—C11—H11	119.4
C17—O4—C18	110.8 (2)	C10—C11—H11	119.4
C7—N1—N2	118.0 (3)	C13—C12—C11	120.3 (5)
C7—N1—Cu1	127.2 (2)	C13—C12—H12	119.8
N2—N1—Cu1	114.77 (18)	C11—C12—H12	119.8
C8—N2—N1	108.4 (2)	C12—C13—C14	120.5 (5)
C19—N3—C16	108.5 (2)	C12—C13—H13	119.7
C19—N3—Cu1	113.09 (19)	C14—C13—H13	119.7
C16—N3—Cu1	116.29 (19)	C13—C14—C15	119.5 (5)
C19—N3—H3	106.1	C13—C14—H14	120.3
C16—N3—H3	106.1	C15—C14—H14	120.3
Cu1—N3—H3	106.1	C10—C15—C14	119.9 (5)
C2—C1—C6	119.3 (3)	C10—C15—Cl1	119.4 (4)
C2—C1—C7	117.4 (3)	C14—C15—Cl1	120.6 (4)
C6—C1—C7	123.3 (3)	N3—C16—C17	109.5 (3)
C3—C2—C1	121.3 (4)	N3—C16—H16A	109.8
C3—C2—H2	119.3	C17—C16—H16A	109.8
C1—C2—H2	119.3	N3—C16—H16B	109.8
C2—C3—C4	119.4 (3)	C17—C16—H16B	109.8
C2—C3—H3A	120.3	H16A—C16—H16B	108.2
C4—C3—H3A	120.3	O4—C17—C16	111.5 (3)
C5—C4—C3	120.7 (4)	O4—C17—H17A	109.3
C5—C4—H4	119.6	C16—C17—H17A	109.3
C3—C4—H4	119.6	O4—C17—H17B	109.3
C4—C5—C6	122.2 (4)	C16—C17—H17B	109.3
C4—C5—H5	118.9	H17A—C17—H17B	108.0
C6—C5—H5	118.9	O4—C18—C19	111.0 (3)
O1—C6—C5	118.7 (3)	O4—C18—H18A	109.4
O1—C6—C1	124.2 (3)	C19—C18—H18A	109.4
C5—C6—C1	117.0 (3)	O4—C18—H18B	109.4
N1—C7—C1	124.1 (3)	C19—C18—H18B	109.4
N1—C7—H7	117.9	H18A—C18—H18B	108.0
C1—C7—H7	117.9	N3—C19—C18	109.5 (2)
O3—C8—N2	125.7 (3)	N3—C19—H19A	109.8
O3—C8—C9	118.2 (3)	C18—C19—H19A	109.8
N2—C8—C9	116.1 (3)	N3—C19—H19B	109.8
O2—C9—C8	112.7 (3)	C18—C19—H19B	109.8
O2—C9—H9A	109.1	H19A—C19—H19B	108.2

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N3—H3···N2^i	0.91	2.08	2.971 (3)	167

Symmetry code: (i) −x+1/2, y+1/2, z.