Di-μ-acetato-κ3O,O′:O;κ3O:O,O′-bis­[(acetato-κ2O,O′)(1,10-phenan­throline-κ2N,N′)cadmium(II)]

Harvey, M.A.; Baggio, S.; Garland, M.T.; Baggio, R.

doi:10.1107/S1600536808029462

Di-μ-acetato-κ³O,O′:O;κ³O:O,O′-bis[(acetato-κ²O,O′)(1,10-phenanthroline-κ²N,N′)cadmium(II)]

M. A. Harvey, S. Baggio, M. T. Garland and R. Baggio

The title compound, [Cd₂(C₂H₃O₂)₄(C₁₂H₈N₂)₂], consists of dimeric units built up around a crystallographic symmetry centre. Each cadmium(II) unit is chelated by a 1,10-phenanthroline (phen) group and two acetate ligands, one of which also acts as a bridge, linking both seven-coordinated cadmium(II) centres. The crystal structure is governed by a single π–π interaction between stacked phen groups [centroid–centroid distance 3.5209 (11) Å], leading to a planar structure parallel to (010).

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Supporting information

	Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536808029462/kj2097sup1.cif Contains datablocks global, I
	Structure factor file (CIF format) https://doi.org/10.1107/S1600536808029462/kj2097Isup2.hkl Contains datablock I

CCDC reference: 709546

checkCIF report

Key indicators

Single-crystal X-ray study
T = 150 K
Mean (C-C) = 0.003 Å
R factor = 0.024
wR factor = 0.065
Data-to-parameter ratio = 15.9

checkCIF/PLATON results

No syntax errors found



Datablock: I


Alert level B
PLAT232_ALERT_2_B Hirshfeld Test Diff (M-X)  Cd1    --  O23     ..      15.26 su

Alert level C
PLAT094_ALERT_2_C Ratio of Maximum / Minimum Residual Density ....       3.94
PLAT232_ALERT_2_C Hirshfeld Test Diff (M-X)  Cd1    --  O14     ..       9.66 su
PLAT232_ALERT_2_C Hirshfeld Test Diff (M-X)  Cd1    --  O24     ..       7.30 su
PLAT241_ALERT_2_C Check High      Ueq as Compared to Neighbors for        O23
PLAT125_ALERT_4_C No _symmetry_space_group_name_Hall Given .......          ?

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

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

Comment top

The title compound consists of dimeric units located around a crystallographic symmetry centre (Fig. 1) and made up of two Cd cations, two 1,10-phenanthroline (phen) molecules and four acetate anions. Each cadmium(II) unit is chelated by a phen group (through both nitrogen atoms), and two acetates (through their carboxylato oxygens). A seventh coordination bond adds to these three chelating bites, by way of one of the latter oxygens which acts also as a bridge linking both cadmium(II) centres (Fig. 1). Table 1 presents the coordination distances achieved. The Cd-Cd distance (Cd1···Cd1ⁱ: 3.846 (1)Å, (i): 2-x, 1-y, 1-z) as well as the O-Cd-O angle (O14-Cd1-O14ⁱ: 72.37 (5) °) are unexceptional.

This coordination scheme of the bis(µ₂-acetato)-bis(acetato)-bis(L) type (L: a chelating aromatic amine) leading to a dimeric unit is not common among transition metal cations and in fact this is the first case reported.

The description of coordination geometries when chelating ligands are involved usually poses intrinsic difficulties which can be elegantly surmounted through a vectorial description of the ligand geometry, as proposed by Harvey et al. (2006) based on the Bond Valence Theory (Brown and Altermatt, 1985). When applied to the present case, the geometrical outcome turns out to be a tetrahedron, with angles between ligand vectors spanning the range 91.3 (1)–124.6 (1)°. The fact that the two main values associated with the theory, i.e. the bond valence sum (2.01 valence units, (v.u).) and the modulus of the bond valence vector (0.06 v.u.), agree almost perfectly with expected values (2.00 v.u. and 0.00 v.u., respectively) suggests a significant stability of this coordination sphere.

Regarding non-covalent interactions, there are just a few and not too strong either. The only hydrogen bond present (Table 2) is a non conventional, intramolecular one linking one of the methyl hydrogens to a carboxylato oxygen (Fig. 1). In fact the packing is governed by a single π···π interaction (Table 3 and Fig. 2) between staked phen groups, which gives raise to weakly interacting planar structures paralell to (010).

Related literature top

For related literature, see: Brown & Altermatt (1985); Janiak (2000). Harvey et al. (2006).

Experimental top

The title compound was obtained by direct mixing of two 0.15 M solutions of cadmium acetate dihydrate and 1,10-phenanthroline in dimethylformamide. Colorless needles began to develop at once, and after one day adequate crystals for X-ray diffraction could be extracted.

Computing details top

Data collection: SMART (Bruker, 2001); cell refinement: SAINT (Bruker, 2001); data reduction: SAINT (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) and PLATON (Spek, 2003).

Figures top

	Fig. 1. The dimeric unit of the title compound: the symmetry-independent part shown in full thermal ellipsoids, drawn at the 40% level. The intradimeric H-bond is shown in dashed lines.
	Fig. 2. Packing view of the title compund down the [010] direction, showing the π···π bonded two-dimensional network.

Di-µ-acetato- κ³O,O':O;κ³O:O,O'- bis[(acetato-κ²O,O')(1,10-phenanthroline- κ²N,N')cadmium(II)] top

Crystal data top

[Cd₂(C₂H₃O₂)₄(C₁₂H₈N₂)₂]	F(000) = 1632
M_r = 821.40	D_x = 1.860 Mg m⁻³
Orthorhombic, Pbca	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ac 2ab	Cell parameters from 11288 reflections
a = 8.4422 (7) Å	θ = 2.7–27.8°
b = 15.6384 (13) Å	µ = 1.51 mm⁻¹
c = 22.2195 (18) Å	T = 150 K
V = 2933.5 (4) Å³	Block, colourless
Z = 4	0.50 × 0.40 × 0.20 mm

Data collection top

Bruker SMART CCD area-detector diffractometer	3331 independent reflections
Radiation source: fine-focus sealed tube	3062 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.020
ϕ and ω scans	θ_max = 27.9°, θ_min = 1.8°
Absorption correction: multi-scan (SADABS; Sheldrick, 2001)	h = −10→11
T_min = 0.50, T_max = 0.74	k = −19→20
22676 measured reflections	l = −28→27

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)] = 0.024	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.064	H-atom parameters constrained
S = 1.06	w = 1/[σ²(F_o²) + (0.0401P)² + 1.4472P] where P = (F_o² + 2F_c²)/3
3331 reflections	(Δ/σ)_max = 0.003
210 parameters	Δρ_max = 1.58 e Å⁻³
0 restraints	Δρ_min = −0.40 e Å⁻³

Crystal data top

[Cd₂(C₂H₃O₂)₄(C₁₂H₈N₂)₂]	V = 2933.5 (4) Å³
M_r = 821.40	Z = 4
Orthorhombic, Pbca	Mo Kα radiation
a = 8.4422 (7) Å	µ = 1.51 mm⁻¹
b = 15.6384 (13) Å	T = 150 K
c = 22.2195 (18) Å	0.50 × 0.40 × 0.20 mm

Data collection top

Bruker SMART CCD area-detector diffractometer	3331 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 2001)	3062 reflections with I > 2σ(I)
T_min = 0.50, T_max = 0.74	R_int = 0.020
22676 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.024	0 restraints
wR(F²) = 0.064	H-atom parameters constrained
S = 1.06	Δρ_max = 1.58 e Å⁻³
3331 reflections	Δρ_min = −0.40 e Å⁻³
210 parameters

Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
Cd1	1.020491 (17)	0.537614 (8)	0.417981 (6)	0.01764 (7)
N1	0.88137 (18)	0.41531 (9)	0.38716 (7)	0.0202 (3)
N2	1.02282 (19)	0.52821 (10)	0.31067 (8)	0.0216 (4)
C1	0.8037 (2)	0.36453 (13)	0.42461 (9)	0.0235 (4)
H1	0.8129	0.3746	0.4666	0.028*
C2	0.7084 (2)	0.29656 (12)	0.40510 (9)	0.0254 (4)
H2	0.6519	0.2626	0.4333	0.030*
C3	0.6983 (2)	0.28003 (12)	0.34466 (9)	0.0262 (4)
H3	0.6364	0.2334	0.3305	0.031*
C4	0.7800 (2)	0.33252 (12)	0.30367 (9)	0.0239 (4)
C5	0.7738 (2)	0.32032 (14)	0.23972 (9)	0.0302 (4)
H5	0.7160	0.2734	0.2238	0.036*
C6	0.8487 (3)	0.37424 (14)	0.20153 (9)	0.0312 (5)
H6	0.8441	0.3641	0.1594	0.037*
C7	0.9354 (2)	0.44695 (13)	0.22400 (9)	0.0256 (4)
C8	1.0118 (2)	0.50644 (16)	0.18593 (10)	0.0294 (5)
H8	1.0089	0.4993	0.1435	0.035*
C9	1.0896 (3)	0.57412 (14)	0.21075 (9)	0.0308 (4)
H9	1.1416	0.6147	0.1858	0.037*
C10	1.0919 (2)	0.58316 (13)	0.27331 (9)	0.0273 (4)
H10	1.1455	0.6310	0.2900	0.033*
C11	0.9455 (2)	0.46042 (11)	0.28630 (9)	0.0209 (4)
C12	0.8686 (2)	0.40117 (11)	0.32713 (8)	0.0199 (4)
C13	1.2479 (2)	0.66285 (12)	0.41072 (8)	0.0207 (4)
C23	1.3877 (3)	0.72303 (14)	0.40927 (9)	0.0286 (4)
H23A	1.3759	0.7629	0.3755	0.043*
H23B	1.4855	0.6901	0.4043	0.043*
H23C	1.3923	0.7552	0.4471	0.043*
O13	1.27330 (18)	0.58473 (9)	0.42176 (6)	0.0282 (3)
O23	1.11146 (17)	0.69086 (10)	0.40168 (8)	0.0354 (3)
C14	0.7547 (2)	0.58393 (11)	0.48087 (8)	0.0192 (3)
C24	0.6115 (2)	0.59980 (13)	0.51958 (9)	0.0252 (4)
H24A	0.6170	0.6576	0.5365	0.038*
H24B	0.6088	0.5579	0.5523	0.038*
H24C	0.5155	0.5943	0.4951	0.038*
O14	0.88527 (15)	0.56447 (8)	0.50710 (6)	0.0229 (3)
O24	0.74741 (18)	0.59082 (9)	0.42510 (6)	0.0247 (3)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Cd1	0.01769 (10)	0.01872 (10)	0.01652 (10)	−0.00151 (4)	−0.00046 (4)	−0.00019 (4)
N1	0.0207 (7)	0.0190 (7)	0.0210 (7)	0.0005 (6)	−0.0011 (6)	−0.0009 (6)
N2	0.0212 (9)	0.0241 (8)	0.0196 (8)	−0.0004 (6)	0.0005 (6)	−0.0009 (6)
C1	0.0231 (10)	0.0235 (10)	0.0238 (9)	0.0010 (8)	−0.0003 (7)	0.0000 (7)
C2	0.0223 (9)	0.0189 (9)	0.0350 (10)	−0.0002 (7)	0.0037 (8)	0.0016 (8)
C3	0.0209 (9)	0.0206 (9)	0.0372 (11)	−0.0006 (7)	−0.0017 (8)	−0.0047 (8)
C4	0.0205 (9)	0.0224 (9)	0.0290 (10)	0.0038 (7)	−0.0037 (7)	−0.0060 (7)
C5	0.0285 (10)	0.0310 (11)	0.0310 (10)	−0.0005 (8)	−0.0076 (8)	−0.0124 (9)
C6	0.0326 (11)	0.0398 (12)	0.0213 (9)	0.0053 (9)	−0.0055 (8)	−0.0101 (8)
C7	0.0231 (10)	0.0318 (10)	0.0220 (9)	0.0070 (8)	−0.0013 (8)	−0.0021 (8)
C8	0.0299 (11)	0.0401 (13)	0.0180 (9)	0.0071 (9)	0.0009 (7)	0.0013 (9)
C9	0.0321 (11)	0.0364 (12)	0.0240 (10)	0.0012 (9)	0.0056 (8)	0.0074 (8)
C10	0.0273 (10)	0.0292 (10)	0.0255 (10)	−0.0034 (8)	0.0028 (8)	0.0029 (8)
C11	0.0168 (9)	0.0213 (9)	0.0248 (10)	0.0044 (7)	−0.0034 (8)	−0.0024 (7)
C12	0.0169 (8)	0.0213 (9)	0.0217 (9)	0.0032 (7)	−0.0018 (7)	−0.0028 (7)
C13	0.0198 (9)	0.0245 (10)	0.0179 (8)	−0.0030 (8)	0.0003 (7)	−0.0008 (7)
C23	0.0239 (10)	0.0263 (10)	0.0355 (11)	−0.0050 (8)	−0.0032 (8)	0.0055 (8)
O13	0.0225 (7)	0.0234 (7)	0.0387 (8)	−0.0037 (6)	−0.0055 (6)	0.0065 (6)
O23	0.0200 (7)	0.0277 (8)	0.0584 (10)	0.0019 (6)	−0.0047 (7)	−0.0034 (7)
C14	0.0204 (8)	0.0138 (8)	0.0233 (9)	−0.0002 (6)	−0.0008 (7)	0.0005 (7)
C24	0.0228 (9)	0.0286 (10)	0.0243 (9)	0.0047 (8)	0.0014 (7)	0.0004 (8)
O14	0.0195 (6)	0.0261 (7)	0.0229 (6)	0.0029 (5)	−0.0011 (5)	0.0022 (5)
O24	0.0248 (7)	0.0291 (7)	0.0201 (6)	0.0023 (6)	−0.0005 (5)	0.0011 (5)

Geometric parameters (Å, º) top

Cd1—O13	2.2594 (15)	C6—H6	0.9500
Cd1—O14	2.3239 (13)	C7—C11	1.403 (3)
Cd1—N1	2.3466 (15)	C7—C8	1.413 (3)
Cd1—N2	2.3890 (18)	C8—C9	1.362 (3)
Cd1—O14ⁱ	2.4398 (13)	C8—H8	0.9500
Cd1—O24	2.4561 (15)	C9—C10	1.397 (3)
Cd1—O23	2.5425 (16)	C9—H9	0.9500
N1—C1	1.324 (2)	C10—H10	0.9500
N1—C12	1.356 (2)	C11—C12	1.450 (3)
N2—C10	1.329 (3)	C13—O23	1.248 (2)
N2—C11	1.358 (2)	C13—O13	1.265 (2)
C1—C2	1.402 (3)	C13—C23	1.510 (3)
C1—H1	0.9500	C23—H23A	0.9800
C2—C3	1.370 (3)	C23—H23B	0.9800
C2—H2	0.9500	C23—H23C	0.9800
C3—C4	1.407 (3)	C14—O24	1.246 (2)
C3—H3	0.9500	C14—O14	1.283 (2)
C4—C12	1.409 (3)	C14—C24	1.504 (2)
C4—C5	1.435 (3)	C24—H24A	0.9800
C5—C6	1.353 (3)	C24—H24B	0.9800
C5—H5	0.9500	C24—H24C	0.9800
C6—C7	1.442 (3)	O14—Cd1ⁱ	2.4398 (13)

O13—Cd1—O14	111.92 (5)	C8—C7—C6	122.93 (19)
O13—Cd1—N1	138.54 (5)	C9—C8—C7	119.28 (19)
O14—Cd1—N1	98.64 (5)	C9—C8—H8	120.4
O13—Cd1—N2	92.83 (5)	C7—C8—H8	120.4
O14—Cd1—N2	149.95 (5)	C8—C9—C10	119.21 (19)
N1—Cd1—N2	70.28 (5)	C8—C9—H9	120.4
O13—Cd1—O14ⁱ	83.11 (5)	C10—C9—H9	120.4
O14—Cd1—O14ⁱ	72.37 (5)	N2—C10—C9	123.3 (2)
N1—Cd1—O14ⁱ	80.16 (5)	N2—C10—H10	118.3
N2—Cd1—O14ⁱ	129.64 (5)	C9—C10—H10	118.3
O13—Cd1—O24	140.70 (6)	N2—C11—C7	122.70 (19)
O14—Cd1—O24	54.75 (4)	N2—C11—C12	117.68 (18)
N1—Cd1—O24	79.93 (5)	C7—C11—C12	119.61 (17)
N2—Cd1—O24	95.33 (5)	N1—C12—C4	122.03 (17)
O14ⁱ—Cd1—O24	118.94 (4)	N1—C12—C11	118.39 (16)
O13—Cd1—O23	54.03 (5)	C4—C12—C11	119.55 (17)
O14—Cd1—O23	95.70 (5)	O23—C13—O13	121.80 (18)
N1—Cd1—O23	151.38 (5)	O23—C13—C23	119.94 (18)
N2—Cd1—O23	85.03 (6)	O13—C13—C23	118.26 (18)
O14ⁱ—Cd1—O23	127.99 (5)	O23—C13—Cd1	67.36 (11)
O24—Cd1—O23	88.47 (5)	O13—C13—Cd1	54.44 (10)
C1—N1—C12	118.75 (16)	C23—C13—Cd1	172.67 (14)
C1—N1—Cd1	123.59 (13)	C13—C23—H23A	109.5
C12—N1—Cd1	117.36 (12)	C13—C23—H23B	109.5
C10—N2—C11	117.80 (18)	H23A—C23—H23B	109.5
C10—N2—Cd1	125.95 (13)	C13—C23—H23C	109.5
C11—N2—Cd1	116.25 (13)	H23A—C23—H23C	109.5
N1—C1—C2	123.00 (18)	H23B—C23—H23C	109.5
N1—C1—H1	118.5	C13—O13—Cd1	98.47 (12)
C2—C1—H1	118.5	C13—O23—Cd1	85.70 (12)
C3—C2—C1	118.82 (18)	O24—C14—O14	120.99 (17)
C3—C2—H2	120.6	O24—C14—C24	120.98 (17)
C1—C2—H2	120.6	O14—C14—C24	118.02 (16)
C2—C3—C4	119.59 (18)	O24—C14—Cd1	63.65 (10)
C2—C3—H3	120.2	O14—C14—Cd1	57.71 (9)
C4—C3—H3	120.2	C24—C14—Cd1	173.24 (13)
C3—C4—C12	117.74 (17)	C14—C24—H24A	109.5
C3—C4—C5	123.09 (18)	C14—C24—H24B	109.5
C12—C4—C5	119.15 (18)	H24A—C24—H24B	109.5
C6—C5—C4	121.43 (19)	C14—C24—H24C	109.5
C6—C5—H5	119.3	H24A—C24—H24C	109.5
C4—C5—H5	119.3	H24B—C24—H24C	109.5
C5—C6—C7	120.77 (18)	C14—O14—Cd1	94.46 (10)
C5—C6—H6	119.6	C14—O14—Cd1ⁱ	138.16 (11)
C7—C6—H6	119.6	Cd1—O14—Cd1ⁱ	107.63 (5)
C11—C7—C8	117.7 (2)	C14—O24—Cd1	89.32 (11)
C11—C7—C6	119.41 (19)

Symmetry code: (i) −x+2, −y+1, −z+1.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C24—H24B···O13ⁱ	0.98	2.51	3.313 (2)	139

Symmetry code: (i) −x+2, −y+1, −z+1.

Experimental details

Crystal data
Chemical formula	[Cd₂(C₂H₃O₂)₄(C₁₂H₈N₂)₂]
M_r	821.40
Crystal system, space group	Orthorhombic, Pbca
Temperature (K)	150
a, b, c (Å)	8.4422 (7), 15.6384 (13), 22.2195 (18)
V (Å³)	2933.5 (4)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	1.51
Crystal size (mm)	0.50 × 0.40 × 0.20

Data collection
Diffractometer	Bruker SMART CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 2001)
T_min, T_max	0.50, 0.74
No. of measured, independent and observed [I > 2σ(I)] reflections	22676, 3331, 3062
R_int	0.020
(sin θ/λ)_max (Å⁻¹)	0.658

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.024, 0.064, 1.06
No. of reflections	3331
No. of parameters	210
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	1.58, −0.40

Computer programs: SMART (Bruker, 2001), SAINT (Bruker, 2001), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2003).

Selected bond lengths (Å) top

Cd1—O13	2.2594 (15)	Cd1—O14ⁱ	2.4398 (13)
Cd1—O14	2.3239 (13)	Cd1—O24	2.4561 (15)
Cd1—N1	2.3466 (15)	Cd1—O23	2.5425 (16)
Cd1—N2	2.3890 (18)

Symmetry code: (i) −x+2, −y+1, −z+1.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C24—H24B···O13ⁱ	0.98	2.51	3.313 (2)	139

Symmetry code: (i) −x+2, −y+1, −z+1.

Table 3. π-π interactions (Å, °) for (I) top

Group 1/Group 2	ccd	ipd	sa
Cg1/Cg2ⁱⁱ	3.5209 (11)	3.50 (1)	4(2)

Symmetry code: (ii) 1/2+x,y,1/2-z

Cg1: N2,C10,C9,C8,C7,C11 Cg2: C4,C5,C6,C7,C11,C12

ccd: center-to-center distance (distance between ring centroids); sa: mean slippage angle (angle subtended by the intercentroid vector to the plane normal); ipd: mean interplanar distance (distance from one plane to the neighbouring centroid). For details, see Janiak (2000).

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Di-μ-acetato-κ3O,O′:O;κ3O:O,O′-bis­[(acetato-κ2O,O′)(1,10-phenan­throline-κ2N,N′)cadmium(II)]

Supporting information

Key indicators

checkCIF/PLATON results

Di-μ-acetato-κ³O,O′:O;κ³O:O,O′-bis[(acetato-κ²O,O′)(1,10-phenanthroline-κ²N,N′)cadmium(II)]