Di­aqua(N-salicyl­idene-L-2-phenyl­glycinate-κ³N,O,O′)copper(II)

The title compound, [Cu(C₁₅H₁₁NO₃)(H₂O)₂], was formed by the reaction of cupric perchlorate, L-α-phenyl­glycine and salicyl­aldehyde. Crystallographic analysis shows that the compound is a new Cu–Schiff base of an amino acid complex. The ligand chelates with Cu^II in a tridentate fashion. One water mol­ecule is in this ligand plane and another is in an axial position. Extensive hydrogen-bonding interactions are present.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.005 Å
• R factor = 0.025
• wR factor = 0.046
• Data-to-parameter ratio = 6.8

checkCIF results

No syntax errors found

ADDSYM reports no extra symmetry


 Alert Level B:



SHFSU_01  Alert B The absolute value of parameter shift to su ratio > 0.10
          Absolute value of the parameter shift to su ratio given   0.116
          Additional refinement cycles may be required.


 Alert Level C:



PLAT_031  Alert C Refined Extinction Parameter within Range ....       2.58 Sigma

General Notes



REFLT_03
         From the CIF: _diffrn_reflns_theta_max           27.48
         From the CIF: _reflns_number_total               1757
         Count of symmetry unique reflns         1761
         Completeness (_total/calc)             99.77%
         TEST3: Check Friedels for noncentro structure
         Estimate of Friedel pairs measured         0
         Fraction of Friedel pairs measured     0.000
         Are heavy atom types Z>Si present          yes
          WARNING: Large fraction of Friedel related reflns may
                   be needed to determine absolute structure


 0 Alert Level A = Potentially serious problem

 1 Alert Level B = Potential problem

 1 Alert Level C = Please check

---

S1. Comment

Transition metal complexes of chiral ligands attract widespread attention from the viewpoint of their structures, molecular recognition, and molecular processes (Whitesides et al., 1995; Philp & Stoddart, 1996). As model systems for pyridoxal-potentiated enzymes, N-salicylidene-L-amino acids are being applied to synthesize a series of transition metal-chiral ligand complexes. Several N-salicylidene-L-amino acids–transition metal complexes have been synthesized and studied, using amino acids with different side-chain groups, such as valine (Rajak et al., 1999), glutamic acid (Korhonen et al., 1984), phenylalanine (Marinovich et al., 1999), alanine (Warda, 1999) and methionine (Palacios et al., 1989).

We report here a new Cu^II complex of N-salicylidene-amino acid, (I), formed from copper(II), L-2-phenyl-glycine and salicylaldehyde. The coordination of the molecule can be described as 4 + 1; each Cu^II ion is coordinated by the carboxylate and phenolate O atoms and amine N atom from the ligand, with bond distances of 1.950 (2), 1.932 (2) and 1.900 (2) Å, respectively, together with one water molecule at 1.960 (2) Å, forming a square-planar geometry. The axial position is occupied by another coordinated water molecule, with a Cu—O distance of 2.400 (3) Å. Except for the phenyl group, all the atoms of the planar set and Cu^II are coplanar, with an average deviation of 0.084 Å. In the crystal structure of the title compound, hydrogen-bonding interactions between the coordinated water molecules and free carboxylate and phenolate O atoms results in a two-dimensional layer structure, as shown in Fig. 2.

S2. Experimental

A 15.0 ml me thanol solution of salicylaldehyde (100 ml, 1.0 mmol) and cupric perchlorate (576 mg, 1.0 mmol) was added into a 15.0 ml suspended aqueous solution of L-2-phenyl-glycine (150 mg, 1.0 mmol). The resulting mixture was stirred until L-2-phenylglycine completely dissolved. Green prismatic single crystals of the title complex (yield 72%) suitable for X-ray diffraction analysis were obtained by evaporation of the filtered mixture at room temperature after 6 days.

S3. Refinement

One reflection, 001, was omitted due to extinction.

Computing details

Data collection: SMART (Siemens, 1996); cell refinement: SMART; data reduction: XPREP in SHELXTL (Siemens, 1994); program(s) used to solve structure: SHELXTL; program(s) used to refine structure: SHELXTL; molecular graphics: SHELXL97 (Siemens, 1996); software used to prepare material for publication: SHELXL97 (Siemens, 1996).

Figures

	Fig. 1. A displacement ellipsoid plot at the 30% probability level.
	Fig. 2. A view of the packing as viewed down the a axis.

Diaqua(N-salicylidene-L-2-phenylglycinate-κ³N,O,O')copper(II)

Crystal data

[Cu(C15H11NO3)(H2O)2]	F(000) = 362
Mr = 352.82	Dx = 1.625 Mg m^−3
Monoclinic, P21	Mo Kα radiation, λ = 0.71073 Å
a = 5.7870 (12) Å	Cell parameters from 64 reflections
b = 9.4205 (19) Å	θ = 2.7–27.5°
c = 13.242 (3) Å	µ = 1.54 mm^−1
β = 92.81 (3)°	T = 293 K
V = 721.0 (3) Å^3	Plate, green
Z = 2	0.40 × 0.36 × 0.16 mm

Data collection

Siemens SMART CCD diffractometer	1757 independent reflections
Radiation source: fine-focus sealed tube	1509 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.034
ω scans	θmax = 27.5°, θmin = 2.7°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −7→7
Tmin = 0.565, Tmax = 0.782	k = −12→12
2514 measured reflections	l = −17→17

Refinement

Refinement on F^2	Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: full	All H-atom parameters refined
R[F^2 > 2σ(F^2)] = 0.025	w = 1/[σ^2(Fo^2) + (0.0224P)^2] where P = (Fo^2 + 2Fc^2)/3
wR(F^2) = 0.046	(Δ/σ)max = 0.116
S = 0.85	Δρmax = 0.23 e Å^−3
1757 reflections	Δρmin = −0.29 e Å^−3
260 parameters	Extinction correction: SHELXL97, Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
1 restraint	Extinction coefficient: 0.0031 (12)
Primary atom site location: structure-invariant direct methods	Absolute structure: Flack (1983), xxxx Friedel pairs
Secondary atom site location: difference Fourier map	Absolute structure parameter: 0.061 (18)

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
N	0.4395 (4)	0.3753 (3)	0.3047 (2)	0.0261 (5)
Cu	0.60243 (5)	0.49428 (7)	0.39962 (3)	0.03050 (11)
O1	0.3988 (4)	0.6544 (2)	0.37471 (18)	0.0360 (5)
O2	0.8241 (4)	0.3384 (3)	0.40933 (18)	0.0353 (6)
O3	0.8516 (4)	0.1071 (2)	0.37928 (18)	0.0418 (6)
O4	0.7923 (4)	0.6198 (3)	0.4877 (2)	0.0421 (6)
O5	0.4049 (5)	0.3883 (3)	0.5359 (2)	0.0409 (6)
C1	0.7514 (5)	0.2243 (3)	0.3706 (2)	0.0306 (7)
C2	0.5184 (5)	0.2257 (3)	0.3101 (2)	0.0261 (6)
C3	0.5234 (5)	0.1508 (3)	0.2096 (2)	0.0305 (7)
C4	0.6976 (7)	0.1751 (4)	0.1436 (3)	0.0464 (9)
C5	0.6983 (8)	0.1031 (6)	0.0525 (3)	0.0606 (12)
C6	0.5329 (8)	0.0059 (8)	0.0266 (3)	0.0627 (12)
C7	0.3605 (8)	−0.0199 (9)	0.0904 (3)	0.0649 (14)
C8	0.3536 (6)	0.0523 (4)	0.1811 (3)	0.0463 (9)
C9	0.2624 (6)	0.4096 (4)	0.2465 (3)	0.0308 (7)
C10	0.1524 (5)	0.5461 (3)	0.2444 (2)	0.0301 (7)
C11	−0.0431 (6)	0.5644 (4)	0.1769 (3)	0.0400 (8)
C12	−0.1707 (7)	0.6853 (5)	0.1746 (3)	0.0455 (10)
C13	−0.1069 (6)	0.7952 (4)	0.2406 (3)	0.0429 (8)
C14	0.0800 (6)	0.7819 (4)	0.3073 (3)	0.0382 (8)
C15	0.2172 (5)	0.6587 (3)	0.3106 (2)	0.0287 (6)
H2	0.410 (5)	0.182 (4)	0.351 (2)	0.025 (8)*
H4	0.820 (7)	0.246 (5)	0.164 (3)	0.050 (12)*
H4A	0.898 (6)	0.612 (5)	0.527 (3)	0.056 (12)*
H4B	0.772 (5)	0.704 (4)	0.484 (2)	0.015 (8)*
H5	0.803 (7)	0.117 (5)	0.012 (3)	0.061 (13)*
H5A	0.327 (7)	0.433 (5)	0.566 (3)	0.056 (16)*
H5B	0.552 (11)	0.325 (8)	0.573 (4)	0.14 (2)*
H6	0.531 (7)	−0.047 (5)	−0.036 (3)	0.067 (14)*
H7	0.248 (8)	−0.091 (6)	0.076 (3)	0.087 (16)*
H8	0.224 (5)	0.038 (4)	0.228 (2)	0.038 (10)*
H9	0.188 (6)	0.341 (5)	0.205 (3)	0.048 (10)*
H11	−0.083 (5)	0.484 (6)	0.133 (2)	0.033 (8)*
H12	−0.289 (7)	0.689 (5)	0.136 (3)	0.056 (12)*
H13	−0.174 (6)	0.877 (4)	0.237 (3)	0.038 (10)*
H14	0.117 (6)	0.856 (5)	0.348 (3)	0.046 (10)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
N	0.0254 (12)	0.0223 (13)	0.0302 (14)	0.0021 (11)	−0.0024 (11)	−0.0027 (12)
Cu	0.03262 (17)	0.02181 (15)	0.03601 (18)	0.0018 (2)	−0.00909 (12)	−0.0030 (3)
O1	0.0386 (12)	0.0244 (12)	0.0435 (14)	0.0035 (10)	−0.0129 (10)	−0.0079 (12)
O2	0.0294 (11)	0.0279 (13)	0.0473 (14)	0.0017 (10)	−0.0106 (10)	−0.0045 (12)
O3	0.0420 (12)	0.0249 (12)	0.0564 (14)	0.0078 (10)	−0.0188 (11)	−0.0013 (11)
O4	0.0466 (15)	0.0231 (14)	0.0542 (16)	−0.0004 (12)	−0.0228 (12)	−0.0042 (12)
O5	0.0480 (14)	0.0306 (13)	0.0442 (14)	0.0047 (12)	0.0022 (11)	0.0054 (12)
C1	0.0319 (14)	0.0259 (16)	0.0333 (15)	0.0046 (14)	−0.0061 (13)	−0.0007 (15)
C2	0.0257 (13)	0.0207 (14)	0.0313 (15)	0.0003 (12)	−0.0041 (12)	0.0026 (13)
C3	0.0326 (14)	0.0241 (15)	0.0340 (15)	0.0064 (13)	−0.0046 (12)	0.0029 (14)
C4	0.0446 (19)	0.044 (2)	0.050 (2)	0.0000 (18)	0.0022 (17)	−0.0028 (19)
C5	0.070 (3)	0.066 (3)	0.047 (2)	0.015 (3)	0.018 (2)	0.002 (2)
C6	0.083 (3)	0.057 (3)	0.046 (2)	0.017 (4)	−0.010 (2)	−0.018 (3)
C7	0.070 (2)	0.059 (4)	0.064 (2)	0.000 (3)	−0.020 (2)	−0.022 (3)
C8	0.0459 (18)	0.043 (2)	0.050 (2)	−0.0081 (16)	−0.0023 (17)	−0.0074 (17)
C9	0.0303 (17)	0.0258 (16)	0.0354 (17)	0.0002 (15)	−0.0071 (15)	−0.0043 (15)
C10	0.0295 (15)	0.0248 (16)	0.0352 (16)	0.0015 (13)	−0.0056 (14)	0.0030 (13)
C11	0.0416 (18)	0.0285 (17)	0.0484 (19)	0.0015 (16)	−0.0123 (16)	−0.0005 (16)
C12	0.0396 (19)	0.041 (2)	0.054 (2)	0.0104 (18)	−0.0154 (18)	0.0039 (19)
C13	0.0404 (18)	0.0314 (19)	0.056 (2)	0.0141 (16)	−0.0027 (16)	0.0052 (18)
C14	0.0435 (18)	0.0283 (17)	0.0422 (18)	0.0065 (16)	−0.0036 (15)	−0.0022 (17)
C15	0.0299 (14)	0.0247 (15)	0.0315 (15)	0.0021 (13)	0.0009 (13)	0.0006 (14)

Geometric parameters (Å, º)

N—C9	1.292 (4)	C4—H4	1.01 (5)
N—C2	1.482 (4)	C5—C6	1.357 (7)
N—Cu	1.900 (2)	C5—H5	0.84 (4)
Cu—O1	1.932 (2)	C6—C7	1.360 (6)
Cu—O2	1.950 (2)	C6—H6	0.96 (4)
Cu—O4	1.960 (3)	C7—C8	1.383 (6)
Cu—O5	2.400 (3)	C7—H7	0.95 (5)
O1—C15	1.319 (3)	C8—H8	1.00 (3)
O2—C1	1.254 (4)	C9—C10	1.435 (5)
O3—C1	1.250 (4)	C9—H9	0.94 (4)
O4—H4B	0.81 (4)	C10—C15	1.415 (5)
O4—H4A	0.79 (4)	C10—C11	1.418 (4)
O5—H5A	0.75 (4)	C11—C12	1.357 (5)
O5—H5B	1.13 (7)	C11—H11	0.98 (5)
C1—C2	1.535 (4)	C12—C13	1.393 (6)
C2—C3	1.507 (4)	C12—H12	0.84 (4)
C2—H2	0.94 (3)	C13—C14	1.369 (5)
C3—C8	1.390 (5)	C13—H13	0.86 (4)
C3—C4	1.385 (5)	C14—C15	1.406 (4)
C4—C5	1.384 (6)	C14—H14	0.90 (4)
C9—N—C2	120.0 (3)	C3—C4—H4	118 (3)
C9—N—Cu	126.9 (2)	C6—C5—C4	121.3 (4)
C2—N—Cu	112.78 (17)	C6—C5—H5	118 (3)
N—Cu—O1	93.93 (10)	C4—C5—H5	121 (3)
N—Cu—O2	84.43 (10)	C5—C6—C7	119.6 (5)
O1—Cu—O2	173.10 (11)	C5—C6—H6	123 (3)
N—Cu—O4	174.51 (13)	C7—C6—H6	117 (3)
O1—Cu—O4	87.12 (11)	C6—C7—C8	120.3 (5)
O2—Cu—O4	93.88 (11)	C6—C7—H7	121 (3)
N—Cu—O5	90.74 (10)	C8—C7—H7	118 (3)
O1—Cu—O5	98.30 (11)	C7—C8—C3	121.0 (4)
O2—Cu—O5	88.44 (10)	C7—C8—H8	121.4 (19)
O4—Cu—O5	94.45 (11)	C3—C8—H8	117.6 (19)
C15—O1—Cu	126.4 (2)	N—C9—C10	125.0 (3)
C1—O2—Cu	114.34 (18)	N—C9—H9	121 (2)
Cu—O4—H4B	119 (2)	C10—C9—H9	114 (2)
Cu—O4—H4A	137 (4)	C15—C10—C11	118.6 (3)
H4B—O4—H4A	104 (4)	C15—C10—C9	123.8 (3)
Cu—O5—H5A	120 (3)	C11—C10—C9	117.5 (3)
Cu—O5—H5B	100 (3)	C12—C11—C10	122.2 (3)
H5A—O5—H5B	122 (4)	C12—C11—H11	122 (2)
O3—C1—O2	125.1 (2)	C10—C11—H11	116 (2)
O3—C1—C2	116.5 (3)	C11—C12—C13	118.8 (3)
O2—C1—C2	118.3 (3)	C11—C12—H12	119 (3)
N—C2—C3	114.9 (2)	C13—C12—H12	122 (3)
N—C2—C1	107.1 (2)	C14—C13—C12	120.9 (3)
C3—C2—C1	113.7 (2)	C14—C13—H13	117 (2)
N—C2—H2	103.5 (19)	C12—C13—H13	122 (2)
C3—C2—H2	110.0 (19)	C13—C14—C15	121.5 (3)
C1—C2—H2	106.8 (18)	C13—C14—H14	118 (2)
C8—C3—C4	117.7 (3)	C15—C14—H14	120 (2)
C8—C3—C2	120.6 (3)	O1—C15—C14	118.5 (3)
C4—C3—C2	121.7 (3)	O1—C15—C10	123.7 (3)
C5—C4—C3	120.2 (4)	C14—C15—C10	117.9 (3)
C5—C4—H4	122 (3)