Aqua­[()-lactate-O,O′](1,10-phenanthroline-κ²N,N′)copper(II) nitrate

In the structure of the title compound, [Cu(C₃H₅O₃)(C₁₂H₈N₂)(H₂O)]NO₃, the Cu^II ion is five-coordinated through two N atoms of the 1,10-phenanthroline ligand, two O atoms of the lactate anion and a water mol­ecule. The cations are well separated in the unit cell, the shortest metal–metal separation being 6.2127 (8) Å.

Key indicators

• Single-crystal X-ray study
• T = 300 K
• Mean [sigma](C-C) = 0.004 Å
• R factor = 0.036
• wR factor = 0.098
• Data-to-parameter ratio = 15.8

checkCIF results

No syntax errors found

ADDSYM reports no extra symmetry

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S1. Comment

A large number of mixed copper chelates of the type [Cu(phen)(O–O)]ⁿ⁺ (n = 0 or 1, phen = different substituted 1,10 phenanthrolines and O–O = acetylacetonate, salycilaldehydate, oxalate or malonate) have been reported. We have studied their relative stability both via solution equilibrium studies, as well as from far IR spectroscopy in the solid state (Gasque, Medina et al., 1999). To validate the latter, isostructurality has first to be established by X-ray diffraction. In this context, most of the crystal structures for the compounds under study have been reported (Fabretti et al., 1985; Kwik et al., 1986; Solans et al., 1987; Su et al., 1995; Gasque, Moreno-Esparza et al., 1999).

Our current interest in relation with this topic is focused on mixed complexes where the O–O ligand is an α-hydroxy acid anion, such as glycolate (Medina et al., 2000) or lactate, of which an example, (I), is presented here.

The asymmetric unit of (I) (Fig. 1) contains one cation and one nitrate anion, both lying on general positions. The copper center is five-coordinated, in a common distorted square-pyramidal geometry, with a τ descriptor (Addison et al., 1984) very close to 0, τ = 0.08. The base of the pyramid is occupied by two O atoms of the racemic lactate ligand and two N atoms of the 1,10-phenanthroline ligand, with the expected coordination bond lengths (Table 1). The metal center is significantly displaced from this plane, the deviation from the calculated least-squares plane (N1, N12, O15 and O18) being 0.2206 (3) Å. This displacement is, for instance, 0.06 Å larger than that observed for the related complex including glycolate instead of lactate (Medina et al., 2000). This difference results from the ability for the nitrate ion to interact with the Cu^II in the glycolate-containing complex, giving a typical Jahn–Teller distorted octahedral coordination geometry, while in (I), an actual five-coordinated complex is obtained; the shortest separation between the anion and the metallic center is Cu1···O22 of 5.000 (3) Å. Finally, the apical coordination site in (I) is occupied by a water molecule, with a long bond length of 2.2283 (19) Å.

The functionality of the cation, together with the presence of nitrate as anion, greatly favors hydrogen bonding in the crystalline state (Table 2). Thus, the hydroxy group O18—H18 of the lactate ligand forms a remarkably strong hydrogen bond with the carboxylate atom O19 of a symmetry-related cation. Remaining significant O—H···O hydrogen bonds involve the coordinated water molecule. The resulting network is a one-dimensional supramolecular aggregate with [101] as base vector (Fig. 2), the steric hindrance of the 1,10-phenanthroline ligand avoiding inter-chain contacts. These features result in large metal–metal separations in the cell, the shortest Cu···Cu distance being Cu···Cuⁱ of 6.2127 (8) Å [symmetry code: (i) 1 − x, −y, 2 − z].

S2. Experimental

The title compound was obtained by mixing 1 mmol of Cu(NO₃)₂·2.5H₂O (0.233 g) with 1 mmol of 1,10-phenanthroline (0.180 g) in 20 ml of MeOH and adding 1 mmol of lithium lactate (0.096 g) previously dissolved in the minimal amount of water. This solution was left standing and air-stable crystals were collected the following day.

S3. Refinement

H atoms for water molecule (H1A and H1B) and hydroxyl group (H18) were found in difference maps. The remaining H atoms, bonded to sp²– and sp³-hybridized C atoms, were placed at idealized positions. In the final cycles, all H atoms were constrained to ride on their parent atoms, with U_iso(H) = xU_eq(parent), where x = 1.5 for Csp³—H and x = 1.2 for for Csp²—H groups. Constrained distances: methine C—H = 0.98 Å, methyl C—H = 0.96 Å and aryl C—H = 0.93 Å.

Computing details

Data collection: XSCANS (Siemens, 1996); cell refinement: XSCANS; data reduction: XSCANS; program(s) used to solve structure: SHELXTL-Plus (Sheldrick, 1998); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL-Plus (Sheldrick, 1998); software used to prepare material for publication: SHELXL97.

Figures

	Fig. 1. The structure of (I) with displacement ellipsoids at the 40% probability level. H atoms are shown as small spheres of arbitrary radii.
	Fig. 2. The one-dimensional chains running along [101] formed by hydrogen bonds in (I). Four asymmetric units are displayed and for the sake of clarity, H atoms not involved in this network have been omitted.

Aqua[(±)-lactate-O,O'](1,10-phenanthroline-κ²N,N')copper(II) nitrate

Crystal data

[Cu(C3H5O3)(C12H8N2)(H2O)]NO3	F(000) = 844
Mr = 412.84	Dx = 1.695 Mg m^−3
Monoclinic, P21/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 68 reflections
a = 8.5646 (13) Å	θ = 4.8–12.5°
b = 19.985 (3) Å	µ = 1.40 mm^−1
c = 9.7854 (13) Å	T = 300 K
β = 104.960 (11)°	Regular prism, blue
V = 1618.2 (4) Å^3	0.62 × 0.26 × 0.22 mm
Z = 4

Data collection

Bruker P4 diffractometer	3156 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.023
Graphite monochromator	θmax = 27.5°, θmin = 2.0°
ω scans	h = −1→11
Absorption correction: gaussian (XSCANS; Siemens, 1996)	k = −25→1
Tmin = 0.599, Tmax = 0.782	l = −12→12
4687 measured reflections	3 standard reflections every 97 reflections
3706 independent reflections	intensity decay: 1.5%

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)] = 0.037	Hydrogen site location: See text
wR(F^2) = 0.099	H-atom parameters constrained
S = 1.04	w = 1/[σ^2(Fo^2) + (0.0487P)^2 + 0.9828P] where P = (Fo^2 + 2Fc^2)/3
3706 reflections	(Δ/σ)max = 0.001
235 parameters	Δρmax = 0.47 e Å^−3
0 restraints	Δρmin = −0.54 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. H atoms for water molecule (H1A, H1B) and hydroxyl group (H18) were found on difference maps and refined as remaining H's (Riding)

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
Cu1	0.32933 (3)	0.138442 (13)	0.96197 (3)	0.03422 (11)
O1	0.1751 (2)	0.19093 (9)	1.0800 (2)	0.0476 (4)
H1A	0.1317	0.2210	1.0371	0.071*
H1B	0.2400	0.2014	1.1624	0.071*
N1	0.1930 (2)	0.05822 (10)	0.8921 (2)	0.0359 (4)
C2	0.0723 (3)	0.05154 (13)	0.7765 (3)	0.0431 (6)
H2A	0.0440	0.0879	0.7157	0.052*
C3	−0.0140 (3)	−0.00842 (14)	0.7428 (3)	0.0473 (6)
H3A	−0.0970	−0.0116	0.6603	0.057*
C4	0.0240 (3)	−0.06221 (13)	0.8314 (3)	0.0445 (6)
H4A	−0.0335	−0.1020	0.8102	0.053*
C5	0.1512 (3)	−0.05677 (12)	0.9551 (3)	0.0389 (5)
C6	0.2008 (3)	−0.10980 (13)	1.0562 (3)	0.0458 (6)
H6A	0.1478	−0.1508	1.0413	0.055*
C7	0.3247 (3)	−0.10032 (12)	1.1734 (3)	0.0463 (6)
H7A	0.3557	−0.1354	1.2372	0.056*
C8	0.4089 (3)	−0.03772 (12)	1.2014 (3)	0.0391 (5)
C9	0.5363 (3)	−0.02492 (14)	1.3217 (3)	0.0464 (6)
H9A	0.5723	−0.0580	1.3894	0.056*
C10	0.6064 (3)	0.03711 (14)	1.3372 (3)	0.0482 (6)
H10A	0.6906	0.0463	1.4163	0.058*
C11	0.5528 (3)	0.08664 (13)	1.2354 (3)	0.0430 (6)
H11A	0.6022	0.1284	1.2485	0.052*
N12	0.4331 (2)	0.07592 (10)	1.1202 (2)	0.0350 (4)
C13	0.3617 (3)	0.01466 (11)	1.1040 (2)	0.0336 (5)
C14	0.2321 (3)	0.00490 (11)	0.9803 (2)	0.0336 (5)
O15	0.2472 (2)	0.18721 (8)	0.78856 (17)	0.0414 (4)
C16	0.3121 (3)	0.24350 (11)	0.7801 (2)	0.0331 (5)
C17	0.4617 (3)	0.26269 (11)	0.8967 (2)	0.0354 (5)
H17A	0.5533	0.2686	0.8550	0.043*
O18	0.4950 (2)	0.20790 (8)	0.99464 (19)	0.0441 (4)
H18	0.5871	0.2140	1.0563	0.066*
O19	0.2643 (2)	0.28460 (9)	0.68378 (18)	0.0430 (4)
C20	0.4369 (4)	0.32612 (13)	0.9706 (3)	0.0513 (7)
H20A	0.5333	0.3364	1.0428	0.077*
H20B	0.3483	0.3204	1.0129	0.077*
H20C	0.4132	0.3621	0.9034	0.077*
N21	0.3937 (3)	0.18194 (11)	0.4271 (2)	0.0469 (5)
O22	0.5171 (3)	0.18147 (13)	0.5268 (3)	0.0796 (8)
O23	0.3678 (3)	0.23108 (11)	0.3466 (3)	0.0720 (7)
O24	0.2997 (3)	0.13421 (11)	0.4069 (3)	0.0681 (6)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Cu1	0.03555 (16)	0.02848 (15)	0.03075 (16)	−0.00216 (10)	−0.00566 (11)	0.00270 (10)
O1	0.0472 (10)	0.0450 (10)	0.0461 (10)	0.0064 (8)	0.0042 (8)	0.0018 (8)
N1	0.0383 (10)	0.0311 (9)	0.0331 (10)	−0.0010 (8)	−0.0002 (8)	0.0003 (7)
C2	0.0434 (13)	0.0411 (13)	0.0369 (12)	−0.0040 (10)	−0.0042 (10)	0.0010 (10)
C3	0.0459 (14)	0.0475 (14)	0.0404 (13)	−0.0090 (11)	−0.0034 (11)	−0.0056 (11)
C4	0.0473 (14)	0.0378 (12)	0.0466 (14)	−0.0091 (10)	0.0088 (11)	−0.0122 (11)
C5	0.0444 (13)	0.0296 (11)	0.0420 (13)	0.0005 (9)	0.0101 (10)	−0.0052 (9)
C6	0.0528 (15)	0.0327 (12)	0.0518 (15)	0.0011 (11)	0.0137 (12)	−0.0006 (11)
C7	0.0574 (15)	0.0283 (11)	0.0522 (15)	0.0076 (10)	0.0123 (12)	0.0083 (10)
C8	0.0412 (12)	0.0338 (11)	0.0412 (12)	0.0077 (9)	0.0084 (10)	0.0042 (10)
C9	0.0474 (14)	0.0438 (13)	0.0427 (13)	0.0073 (11)	0.0020 (11)	0.0120 (11)
C10	0.0439 (14)	0.0523 (15)	0.0390 (13)	0.0011 (11)	−0.0062 (10)	0.0070 (11)
C11	0.0411 (13)	0.0406 (12)	0.0391 (12)	−0.0023 (10)	−0.0045 (10)	0.0033 (10)
N12	0.0347 (10)	0.0323 (9)	0.0328 (9)	0.0007 (8)	−0.0007 (8)	0.0021 (7)
C13	0.0349 (11)	0.0290 (10)	0.0346 (11)	0.0030 (9)	0.0049 (9)	0.0002 (9)
C14	0.0362 (11)	0.0287 (10)	0.0344 (11)	0.0009 (8)	0.0063 (9)	−0.0026 (8)
O15	0.0421 (9)	0.0368 (9)	0.0338 (8)	−0.0096 (7)	−0.0108 (7)	0.0046 (7)
C16	0.0286 (10)	0.0343 (11)	0.0293 (10)	−0.0008 (8)	−0.0052 (8)	0.0005 (8)
C17	0.0295 (10)	0.0346 (11)	0.0343 (11)	−0.0033 (8)	−0.0061 (8)	0.0062 (9)
O18	0.0348 (8)	0.0367 (8)	0.0451 (9)	−0.0040 (7)	−0.0180 (7)	0.0106 (7)
O19	0.0407 (9)	0.0386 (9)	0.0376 (9)	−0.0048 (7)	−0.0120 (7)	0.0098 (7)
C20	0.0577 (16)	0.0385 (13)	0.0449 (14)	0.0007 (12)	−0.0098 (12)	−0.0045 (11)
N21	0.0469 (12)	0.0429 (12)	0.0456 (12)	0.0025 (10)	0.0025 (10)	−0.0019 (9)
O22	0.0641 (14)	0.0782 (17)	0.0734 (16)	−0.0074 (12)	−0.0240 (12)	0.0075 (13)
O23	0.0983 (18)	0.0507 (12)	0.0569 (13)	−0.0050 (12)	0.0017 (12)	0.0095 (10)
O24	0.0598 (13)	0.0535 (13)	0.0791 (16)	−0.0131 (10)	−0.0036 (11)	0.0039 (11)

Geometric parameters (Å, º)

Cu1—O15	1.9256 (16)	C8—C9	1.407 (4)
Cu1—O18	1.9516 (17)	C9—C10	1.369 (4)
Cu1—N1	1.9970 (19)	C9—H9A	0.9300
Cu1—N12	2.0096 (19)	C10—C11	1.395 (4)
Cu1—O1	2.2283 (19)	C10—H10A	0.9300
Cu1—Cu1^i	6.2127 (8)	C11—N12	1.331 (3)
O1—H1A	0.7711	C11—H11A	0.9300
O1—H1B	0.8785	N12—C13	1.360 (3)
N1—C2	1.328 (3)	C13—C14	1.429 (3)
N1—C14	1.357 (3)	O15—C16	1.267 (3)
C2—C3	1.402 (4)	C16—O19	1.238 (3)
C2—H2A	0.9300	C16—C17	1.528 (3)
C3—C4	1.367 (4)	C17—O18	1.435 (3)
C3—H3A	0.9300	C17—C20	1.502 (4)
C4—C5	1.409 (4)	C17—H17A	0.9800
C4—H4A	0.9300	O18—H18	0.8690
C5—C14	1.404 (3)	C20—H20A	0.9600
C5—C6	1.437 (4)	C20—H20B	0.9600
C6—C7	1.360 (4)	C20—H20C	0.9600
C6—H6A	0.9300	N21—O24	1.231 (3)
C7—C8	1.435 (4)	N21—O22	1.239 (3)
C7—H7A	0.9300	N21—O23	1.243 (3)
C8—C13	1.403 (3)
O15—Cu1—O18	82.49 (7)	C9—C8—C7	124.2 (2)
O15—Cu1—N1	93.24 (7)	C10—C9—C8	118.7 (2)
O18—Cu1—N1	164.40 (9)	C10—C9—H9A	120.6
O15—Cu1—N12	169.12 (8)	C8—C9—H9A	120.6
O18—Cu1—N12	99.07 (7)	C9—C10—C11	120.6 (2)
N1—Cu1—N12	82.40 (8)	C9—C10—H10A	119.7
O15—Cu1—O1	95.03 (8)	C11—C10—H10A	119.7
O18—Cu1—O1	94.78 (8)	N12—C11—C10	122.0 (2)
N1—Cu1—O1	100.55 (8)	N12—C11—H11A	119.0
N12—Cu1—O1	95.57 (8)	C10—C11—H11A	119.0
O15—Cu1—Cu1^i	127.59 (6)	C11—N12—C13	118.0 (2)
O18—Cu1—Cu1^i	108.31 (5)	C11—N12—Cu1	130.06 (17)
N1—Cu1—Cu1^i	62.70 (6)	C13—N12—Cu1	111.93 (14)
N12—Cu1—Cu1^i	41.66 (6)	N12—C13—C8	123.4 (2)
O1—Cu1—Cu1^i	132.90 (5)	N12—C13—C14	116.73 (19)
Cu1—O1—H1A	110.6	C8—C13—C14	119.9 (2)
Cu1—O1—H1B	105.6	N1—C14—C5	123.3 (2)
H1A—O1—H1B	114.6	N1—C14—C13	116.18 (19)
C2—N1—C14	118.2 (2)	C5—C14—C13	120.6 (2)
C2—N1—Cu1	129.05 (17)	C16—O15—Cu1	116.12 (14)
C14—N1—Cu1	112.74 (15)	O19—C16—O15	125.1 (2)
N1—C2—C3	122.2 (2)	O19—C16—C17	116.8 (2)
N1—C2—H2A	118.9	O15—C16—C17	118.15 (19)
C3—C2—H2A	118.9	O18—C17—C20	110.5 (2)
C4—C3—C2	119.9 (2)	O18—C17—C16	106.91 (17)
C4—C3—H3A	120.0	C20—C17—C16	112.1 (2)
C2—C3—H3A	120.0	O18—C17—H17A	109.1
C3—C4—C5	119.3 (2)	C20—C17—H17A	109.1
C3—C4—H4A	120.3	C16—C17—H17A	109.1
C5—C4—H4A	120.3	C17—O18—Cu1	115.01 (12)
C14—C5—C4	117.1 (2)	C17—O18—H18	110.2
C14—C5—C6	118.8 (2)	Cu1—O18—H18	134.8
C4—C5—C6	124.1 (2)	C17—C20—H20A	109.5
C7—C6—C5	120.3 (2)	C17—C20—H20B	109.5
C7—C6—H6A	119.8	H20A—C20—H20B	109.5
C5—C6—H6A	119.8	C17—C20—H20C	109.5
C6—C7—C8	121.8 (2)	H20A—C20—H20C	109.5
C6—C7—H7A	119.1	H20B—C20—H20C	109.5
C8—C7—H7A	119.1	O24—N21—O22	120.7 (3)
C13—C8—C9	117.3 (2)	O24—N21—O23	120.5 (2)
C13—C8—C7	118.6 (2)	O22—N21—O23	118.8 (3)
O15—Cu1—N1—C2	−10.4 (2)	Cu1—N12—C13—C8	−178.60 (19)
O18—Cu1—N1—C2	−83.8 (4)	C11—N12—C13—C14	179.1 (2)
N12—Cu1—N1—C2	179.7 (2)	Cu1—N12—C13—C14	1.3 (3)
O1—Cu1—N1—C2	85.4 (2)	C9—C8—C13—N12	0.4 (4)
Cu1^i—Cu1—N1—C2	−141.5 (2)	C7—C8—C13—N12	180.0 (2)
O15—Cu1—N1—C14	171.03 (17)	C9—C8—C13—C14	−179.5 (2)
O18—Cu1—N1—C14	97.6 (3)	C7—C8—C13—C14	0.1 (4)
N12—Cu1—N1—C14	1.04 (17)	C2—N1—C14—C5	0.0 (4)
O1—Cu1—N1—C14	−93.24 (17)	Cu1—N1—C14—C5	178.78 (19)
Cu1^i—Cu1—N1—C14	39.85 (14)	C2—N1—C14—C13	−179.4 (2)
C14—N1—C2—C3	−0.5 (4)	Cu1—N1—C14—C13	−0.6 (3)
Cu1—N1—C2—C3	−179.0 (2)	C4—C5—C14—N1	0.1 (4)
N1—C2—C3—C4	0.9 (4)	C6—C5—C14—N1	−179.2 (2)
C2—C3—C4—C5	−0.7 (4)	C4—C5—C14—C13	179.5 (2)
C3—C4—C5—C14	0.2 (4)	C6—C5—C14—C13	0.2 (4)
C3—C4—C5—C6	179.5 (3)	N12—C13—C14—N1	−0.5 (3)
C14—C5—C6—C7	−0.5 (4)	C8—C13—C14—N1	179.4 (2)
C4—C5—C6—C7	−179.8 (3)	N12—C13—C14—C5	−179.9 (2)
C5—C6—C7—C8	0.6 (4)	C8—C13—C14—C5	0.0 (4)
C6—C7—C8—C13	−0.4 (4)	O18—Cu1—O15—C16	−10.20 (18)
C6—C7—C8—C9	179.1 (3)	N1—Cu1—O15—C16	−175.13 (18)
C13—C8—C9—C10	0.1 (4)	N12—Cu1—O15—C16	−109.2 (4)
C7—C8—C9—C10	−179.5 (3)	O1—Cu1—O15—C16	83.98 (18)
C8—C9—C10—C11	−0.2 (4)	Cu1^i—Cu1—O15—C16	−117.56 (17)
C9—C10—C11—N12	−0.2 (5)	Cu1—O15—C16—O19	−172.1 (2)
C10—C11—N12—C13	0.6 (4)	Cu1—O15—C16—C17	8.2 (3)
C10—C11—N12—Cu1	178.0 (2)	O19—C16—C17—O18	−179.5 (2)
O15—Cu1—N12—C11	114.3 (4)	O15—C16—C17—O18	0.2 (3)
O18—Cu1—N12—C11	16.9 (2)	O19—C16—C17—C20	59.3 (3)
N1—Cu1—N12—C11	−178.8 (2)	O15—C16—C17—C20	−121.1 (3)
O1—Cu1—N12—C11	−78.8 (2)	C20—C17—O18—Cu1	113.9 (2)
Cu1^i—Cu1—N12—C11	124.3 (3)	C16—C17—O18—Cu1	−8.3 (2)
O15—Cu1—N12—C13	−68.2 (4)	O15—Cu1—O18—C17	10.21 (17)
O18—Cu1—N12—C13	−165.58 (16)	N1—Cu1—O18—C17	85.1 (3)
N1—Cu1—N12—C13	−1.27 (16)	N12—Cu1—O18—C17	179.33 (17)
O1—Cu1—N12—C13	98.66 (16)	O1—Cu1—O18—C17	−84.25 (17)
Cu1^i—Cu1—N12—C13	−58.17 (14)	Cu1^i—Cu1—O18—C17	137.40 (16)
C11—N12—C13—C8	−0.8 (4)

Symmetry code: (i) −x+1, −y, −z+2.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O18—H18···O19^ii	0.87	1.70	2.562 (2)	172
O1—H1B···O23^iii	0.88	1.94	2.819 (3)	174
O1—H1A···O22^iv	0.77	2.17	2.871 (3)	151
O1—H1B···N21^iii	0.88	2.61	3.434 (3)	156

Symmetry codes: (ii) x+1/2, −y+1/2, z+1/2; (iii) x, y, z+1; (iv) x−1/2, −y+1/2, z+1/2.