Di­aqua­bis­(cinnamato-κ2O,O′)cadmium

Chooset, S.; Cunningham, B.; Kantacha, A.; Zeller, M.; Wongnawa, S.

doi:10.1107/S160053681400364X

metal-organic compounds

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ISSN: 2056-9890

Volume 70| Part 3| March 2014| Pages m106-m107

doi:10.1107/S160053681400364X

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Diaquabis(cinnamato-κ²O,O′)cadmium

Sirinart Chooset,^a Bryan Cunningham,^b Anob Kantacha,^c Matthias Zeller ^b and Sumpun Wongnawa ^a ^*

^aDepartment of Chemistry, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla 90112, Thailand, ^bDepartment of Chemistry, Youngstown State University, One University Plaza, Youngstown, OH 44555, USA, and ^cDepartment of Chemistry, Faculty of Science, Thaksin University, (Patthalung Campus), Patthalung 93110, Thailand
^*Correspondence e-mail: sumpun.w@psu.ac.th

(Received 23 January 2014; accepted 18 February 2014; online 26 February 2014)

The title complex, [Cd(C₉H₇O₂)₂(H₂O)₂], was obtained as an unintended product of the reaction of cadmium nitrate with hexamethylenetetramine and cinnamic acid. The Cd^II ion lies on a twofold rotation axis and is coordinated in a slightly distorted trigonal–prismatic environment. In the crystal, the V-shaped molecules are arranged in an interlocking fashion along [010] and O—H⋯O hydrogen bonds link the molecules, forming a two-dimensional network parallel to (001).

CCDC reference: 987495

Related literature

For a previous conference report of the title compound, see: Amma et al. (1983 ). For related structures, see: Hosomi et al. (2000 ); Mak et al. (1985 ); Smith et al. (1981 ); O'Reilly et al. (1984 ). For a description of the Cambridge Structural Database, see: Allen (2002 ).

Experimental

Crystal data

[Cd(C₉H₇O₂)₂(H₂O)₂]
M_r = 442.72
Monoclinic, C 2
a = 11.7872 (12) Å
b = 5.3498 (5) Å
c = 13.8817 (14) Å
β = 99.913 (1)°
V = 862.30 (15) Å³
Z = 2
Mo Kα radiation
μ = 1.30 mm⁻¹
T = 100 K
0.28 × 0.09 × 0.02 mm

Data collection

Bruker SMART APEX CCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2012 ) T_min = 0.617, T_max = 0.746
5087 measured reflections
2531 independent reflections
2529 reflections with I > 2σ(I)
R_int = 0.021

Refinement

R[F² > 2σ(F²)] = 0.020
wR(F²) = 0.046
S = 1.05
2531 reflections
150 parameters
3 restraints
All H-atom parameters refined
Δρ_max = 1.09 e Å⁻³
Δρ_min = −0.42 e Å⁻³
Absolute structure: Flack parameter determined using 1059 quotients [(I⁺)−(I⁻)]/[(I⁺)+(I⁻)] (Parsons et al., 2013 )
Absolute structure parameter: 0.018 (14)

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O3—H3A⋯O1ⁱ	0.82 (2)	1.86 (2)	2.679 (3)	174 (4)
O3—H3B⋯O2ⁱⁱ	0.80 (2)	1.86 (3)	2.658 (3)	171 (5)
Symmetry codes: (i) -x+2, y-1, -z+2; (ii) $[-x+{\script{3\over 2}}, y-{\script{1\over 2}}, -z+2]$ .

Data collection: APEX2 (Bruker, 2012); cell refinement: SAINT (Bruker, 2012); data reduction: SAINT and SHELXTL (Sheldrick, 2008 ); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2013 (Sheldrick, 2008) and SHELXLE (Hübschle et al., 2011 ); molecular graphics: Mercury (Macrae et al., 2008 ) and PLATON (Spek, 2009 ); software used to prepare material for publication: publCIF (Westrip, 2010 ).

Supporting information

CCDC reference: 987495

Crystal structure: contains datablocks I, global. DOI: 10.1107/S160053681400364X/lh5688sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S160053681400364X/lh5688Isup2.hkl

checkCIF report

Comment top

The title compound was obtained as an accidental product of the reaction of cadmium nitrate with hexamethylenetetramine and cinnamic acid in ethanol in an attempt to synthesize a potentially interesting framework compound of the metal with both tetraamine and carboxylic acid groups. The potentially bridging hexamethylenetetramine ligand may have acted as a linker between cadmium ions; however, it was not incorporated into the material. A mononuclear cadmium complex with water and cinnamate ligands was the product formed in 75% yield, from an ethanolic solution.

The structure of diaqua-bis(cinnamato)-cadmium(II) had been previously recorded and was presented at the 1983 meeting of the American Chemical Society, but complete structural details are not available (Amma et al., 1983). In the Cambridge Structural Database (Version 5.35, with updates up to May 2013; Allen, 2002) [REFCODE: BUYTUK] only the data collection temperature (room temperature), unit cell parameters and space group, and the R value (10.4%) are reported but no atomic coordinates are available. Given the relatively poor precision of the previously reported structure and the lack of three-dimensional coordinates, we herein report the crystal structure of the title compound at 100 K.

The Cd^II lies on a two-fold rotation axis and is coordinated by two cinnamate ligands and two water molecules (Fig. 1). The carboxylate groups are bidentate-chelating, the water molecules monodentate and non bridging. The two oxygen atoms of each carboxylate group take coordination sites, the overall coordination environment of the metal center is best described as distorted trigonal prism, with angles varying between 92.86 (11)° (between the O atoms of the two water molecules), and 116.30 (8)° (for the angle between a water molecule O atom and a neighboring carboxylate group, using the carboxylate carbon atom as a substitute for the average of the two oxygen atoms).

The Cd—O bond distances are in the expected ranges. The bonds involving the water O atoms are 2.208 (2) Å , which compares well with those in similar Cd(II) complexes (O'Reilly et al., 1984, Mak et al., 1985). The Cd—O bond distances involving the two carboxylate O atoms are longer than those involving the water molecules, as would be expected due to the chelating coordination mode of the cinnamate ligand. The actual bond distances are 2.330 (2) and 2.375 (2) Å for Cd—O1 and Cd—O2, respectively. The similarity of the two Cd—O distances indicates an essentially symmetric coordination and a delocalization of the negative charge of the cinnamate carboxylate group. This is confirmed by the C—O bond distances within the carboxylate groups, which are also the same within experimental error, with values of 1.276 (3) and 1.269 (3) Å for O1—C9 and O2—C9, respectively.

In the crystal, the V-shape of the molecule results in a linear arrangement along [010] with the Cd(OH₂)₂ part of one molecule oriented towards the V-shaped part of a symmetry related molecule (Fig. 2). In addition, intermolecular O—H···O hydrogen bonds connect molecules forming a two-dimensional network parallel to (001) (Fig. 3).

A search against the Cambridge Structural Database provided several similar reported structures that are related to the title compound: the zinc derivative diaqua-bis(cinnamato)-zinc(II) (Hosomi et al., 2000; CSD refcode KIYSEQ), and several of the zinc and cadmium phenoxyacetato derivatives: diaqua-bis(phenoxyacetato)-cadmium(II) (Mak et al., 1985, csd refcode DEBGAS) and diaqua-bis(phenoxyacetato)-zinc(II) (Smith et al., 1981, CSD refcode PHXCUB), diaqua-bis(4-fluorophenoxyacetato)-cadmium(II) (O'Reilly et al., 1984; CSD refcode CUPMUV). Figures 4 and 5 show representative overlays of the title compound diaqua-bis(cinnamic)-cadmium(II) with diaqua-bis(phenoxyacetato)-zinc(II) (Smith et al., 1981), indicating the isomorphous nature of the two compounds.

Related literature top

For a previous conference report of the title compound without three-dimensional coordinates, see: Amma et al. (1983). For related structures, see: Hosomi et al. (2000); Mak et al. (1985); Smith et al. (1981); O'Reilly et al. (1984). For a description of the Cambridge Structural Database, see: Allen (2002).

Experimental top

To a stirred colorless solution of Cd(NO₃)₂·4H₂O (0.3084 g, 1 mmol) in 10 mL of water was added hexamethylenetetramine (0.2802 g, 2 mmol) in 5 mL of water to give a colorless solution. Then, cinnamic acid (0.2962 g, 2 mmol) in 20 mL of ethanol was added to a give a colorless solution. The solution was stirred at room temperature for 6 h, was filtered and then left to evaporate at room temperature. After several days, colorless needle shaped crystals suitable for X-ray analysis were obtained in 75% yield. A single-crystal was isolated while suspended in mineral oil, was mounted with the help of a trace of mineral oil on a Mitegen micromesh mount and flash frozen to 100 K on the diffractometer.

Computing details top

Data collection: APEX2 (Bruker, 2012); cell refinement: SAINT (Bruker, 2012); data reduction: SAINT (Bruker, 2012) and SHELXTL (Sheldrick, 2008); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2013 (Sheldrick, 2008) and SHELXLE (Hübschle et al., 2011); molecular graphics: Mercury (Macrae et al., 2008) and PLATON (Spek, 2009); software used to prepare material for publication: publCIF (Westrip, 2010).

Figures top

	Fig. 1. The molecular structure of the title compund, shown with ellipsoids at the 50% probability level. Symmetry operator (i): –x + 2, y, –z + 2.
	Fig. 2. Part of the crystal structure showing molecules arranged along [010]. Hydrogen bonds are shown as blue dotted lines.
	Fig. 3. Part of the crystal structure showing layers perpendicular to the c-axis direction of the structure. Hydrogen bonds are illustrated by blue dotted lines.
	Fig. 4. Overlaid stick presentation of diaqua-bis(cinnamate)-cadmium(II) (blue) and diaqua-bis(phenoxyacetato)-zinc(II) (red) (Smith et al., 1981).
	Fig. 5. Overlaid stick presentation of diaqua-bis(cinnamic)-cadmium(ii) (blue) and diaqua-bis(phenoxyacetato)-zinc(II) (red) (Smith et al., 1981).

Diaquabis(cinnamato-κ²O,O')cadmium top

Crystal data top

[Cd(C₉H₇O₂)₂(H₂O)₂]	F(000) = 444
M_r = 442.72	D_x = 1.705 Mg m⁻³
Monoclinic, C2	Mo Kα radiation, λ = 0.71073 Å
a = 11.7872 (12) Å	Cell parameters from 4501 reflections
b = 5.3498 (5) Å	θ = 3.0–31.4°
c = 13.8817 (14) Å	µ = 1.30 mm⁻¹
β = 99.913 (1)°	T = 100 K
V = 862.30 (15) Å³	Plate, colourless
Z = 2	0.28 × 0.09 × 0.02 mm

Data collection top

Bruker SMART APEX CCD diffractometer	2531 independent reflections
Radiation source: fine focus sealed tube	2529 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.021
ω and φ scans	θ_max = 31.4°, θ_min = 3.0°
Absorption correction: multi-scan (SADABS; Bruker, 2012)	h = −17→16
T_min = 0.617, T_max = 0.746	k = −7→7
5087 measured reflections	l = −20→19

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: difference Fourier map
R[F² > 2σ(F²)] = 0.020	All H-atom parameters refined
wR(F²) = 0.046	w = 1/[σ²(F_o²) + (0.0239P)²] where P = (F_o² + 2F_c²)/3
S = 1.05	(Δ/σ)_max = 0.002
2531 reflections	Δρ_max = 1.09 e Å⁻³
150 parameters	Δρ_min = −0.42 e Å⁻³
3 restraints	Absolute structure: Flack parameter determined using 1059 quotients [(I⁺)-(I^-)]/[(I⁺)+(I^-)] (Parsons et al., 2013)
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: 0.018 (14)

Crystal data top

[Cd(C₉H₇O₂)₂(H₂O)₂]	V = 862.30 (15) Å³
M_r = 442.72	Z = 2
Monoclinic, C2	Mo Kα radiation
a = 11.7872 (12) Å	µ = 1.30 mm⁻¹
b = 5.3498 (5) Å	T = 100 K
c = 13.8817 (14) Å	0.28 × 0.09 × 0.02 mm
β = 99.913 (1)°

Data collection top

Bruker SMART APEX CCD diffractometer	2531 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2012)	2529 reflections with I > 2σ(I)
T_min = 0.617, T_max = 0.746	R_int = 0.021
5087 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.020	All H-atom parameters refined
wR(F²) = 0.046	Δρ_max = 1.09 e Å⁻³
S = 1.05	Δρ_min = −0.42 e Å⁻³
2531 reflections	Absolute structure: Flack parameter determined using 1059 quotients [(I⁺)-(I^-)]/[(I⁺)+(I^-)] (Parsons et al., 2013)
150 parameters	Absolute structure parameter: 0.018 (14)
3 restraints

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.

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

	x	y	z	U_iso*/U_eq
Cd1	1.0000	0.42839 (2)	1.0000	0.00869 (6)
O3	0.90970 (17)	0.1439 (4)	1.07385 (17)	0.0152 (4)
H3A	0.943 (3)	0.013 (5)	1.091 (3)	0.020 (10)*
H3B	0.841 (2)	0.127 (10)	1.064 (4)	0.044 (14)*
O1	0.96843 (16)	0.7270 (4)	0.87606 (14)	0.0116 (4)
C1	0.8274 (2)	1.4604 (9)	0.65368 (19)	0.0130 (8)
H1	0.910 (3)	1.43 (2)	0.661 (2)	0.027 (8)*
O2	0.81721 (16)	0.6060 (4)	0.93838 (15)	0.0129 (4)
C2	0.7702 (3)	1.6408 (5)	0.5914 (2)	0.0160 (5)
H2	0.810 (3)	1.741 (8)	0.558 (3)	0.013 (9)*
C3	0.6509 (3)	1.6611 (6)	0.5806 (2)	0.0170 (5)
H3	0.615 (3)	1.787 (8)	0.540 (3)	0.020 (10)*
C4	0.5903 (3)	1.5009 (6)	0.6322 (2)	0.0180 (6)
H4	0.505 (3)	1.511 (7)	0.623 (3)	0.021 (10)*
C5	0.6473 (3)	1.3212 (6)	0.6945 (2)	0.0163 (5)
H5	0.605 (3)	1.209 (8)	0.726 (3)	0.020 (10)*
C6	0.7674 (2)	1.2971 (5)	0.70604 (19)	0.0116 (5)
C7	0.8322 (2)	1.1060 (5)	0.76880 (19)	0.0113 (5)
H7	0.915 (3)	1.100 (7)	0.769 (3)	0.019 (10)*
C8	0.7895 (2)	0.9423 (16)	0.82500 (18)	0.0134 (6)
H8	0.708 (3)	0.92 (2)	0.831 (3)	0.031 (9)*
C9	0.8621 (2)	0.7486 (5)	0.88228 (19)	0.0097 (4)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Cd1	0.00734 (9)	0.00637 (10)	0.01212 (10)	0.000	0.00096 (6)	0.000
O3	0.0085 (9)	0.0093 (9)	0.0282 (11)	0.0011 (7)	0.0046 (8)	0.0044 (8)
O1	0.0089 (8)	0.0106 (9)	0.0152 (9)	0.0004 (7)	0.0022 (7)	0.0007 (7)
C1	0.0150 (10)	0.011 (2)	0.0127 (10)	−0.0026 (11)	0.0010 (8)	0.0008 (10)
O2	0.0082 (8)	0.0122 (9)	0.0179 (9)	−0.0003 (7)	0.0013 (7)	0.0047 (7)
C2	0.0233 (14)	0.0117 (12)	0.0128 (12)	−0.0010 (10)	0.0027 (10)	0.0027 (10)
C3	0.0237 (14)	0.0140 (13)	0.0122 (12)	0.0054 (11)	0.0001 (10)	0.0019 (10)
C4	0.0170 (12)	0.0210 (15)	0.0158 (13)	0.0058 (9)	0.0024 (11)	0.0034 (9)
C5	0.0158 (12)	0.0182 (13)	0.0152 (13)	0.0025 (10)	0.0038 (11)	0.0040 (10)
C6	0.0142 (12)	0.0113 (13)	0.0091 (11)	0.0020 (9)	0.0013 (9)	−0.0010 (9)
C7	0.0118 (11)	0.0110 (12)	0.0104 (11)	0.0014 (9)	−0.0002 (9)	0.0001 (9)
C8	0.0109 (9)	0.0130 (15)	0.0158 (9)	0.0069 (19)	0.0015 (7)	0.0020 (19)
C9	0.0100 (11)	0.0082 (11)	0.0103 (11)	−0.0015 (9)	−0.0003 (9)	−0.0012 (9)

Geometric parameters (Å, º) top

Cd1—O3ⁱ	2.208 (2)	O2—C9	1.269 (3)
Cd1—O3	2.208 (2)	C2—C3	1.392 (4)
Cd1—O1ⁱ	2.330 (2)	C2—H2	0.89 (4)
Cd1—O1	2.330 (2)	C3—C4	1.391 (4)
Cd1—O2	2.3753 (19)	C3—H3	0.94 (4)
Cd1—O2ⁱ	2.375 (2)	C4—C5	1.386 (4)
Cd1—C9	2.708 (3)	C4—H4	0.99 (4)
Cd1—C9ⁱ	2.708 (3)	C5—C6	1.403 (4)
O3—H3A	0.82 (2)	C5—H5	0.93 (4)
O3—H3B	0.80 (2)	C6—C7	1.469 (4)
O1—C9	1.276 (3)	C7—C8	1.328 (7)
C1—C2	1.390 (5)	C7—H7	0.98 (4)
C1—C6	1.403 (5)	C8—C9	1.485 (7)
C1—H1	0.98 (4)	C8—H8	0.99 (4)

O3ⁱ—Cd1—O3	92.86 (11)	C2—C1—C6	121.4 (3)
O3ⁱ—Cd1—O1ⁱ	141.89 (7)	C2—C1—H1	124 (5)
O3—Cd1—O1ⁱ	99.10 (8)	C6—C1—H1	114 (5)
O3ⁱ—Cd1—O1	99.10 (8)	C9—O2—Cd1	90.74 (15)
O3—Cd1—O1	141.89 (7)	C1—C2—C3	119.6 (3)
O1ⁱ—Cd1—O1	93.45 (10)	C1—C2—H2	120 (3)
O3ⁱ—Cd1—O2	126.04 (8)	C3—C2—H2	121 (2)
O3—Cd1—O2	87.88 (7)	C4—C3—C2	119.7 (3)
O1ⁱ—Cd1—O2	90.65 (7)	C4—C3—H3	122 (2)
O1—Cd1—O2	55.96 (7)	C2—C3—H3	118 (2)
O3ⁱ—Cd1—O2ⁱ	87.88 (7)	C5—C4—C3	120.8 (3)
O3—Cd1—O2ⁱ	126.04 (8)	C5—C4—H4	120 (2)
O1ⁱ—Cd1—O2ⁱ	55.96 (7)	C3—C4—H4	120 (2)
O1—Cd1—O2ⁱ	90.65 (7)	C4—C5—C6	120.4 (3)
O2—Cd1—O2ⁱ	132.85 (10)	C4—C5—H5	119 (3)
O3ⁱ—Cd1—C9	116.30 (8)	C6—C5—H5	120 (3)
O3—Cd1—C9	115.41 (8)	C5—C6—C1	118.2 (3)
O1ⁱ—Cd1—C9	90.85 (7)	C5—C6—C7	122.9 (3)
O1—Cd1—C9	28.08 (7)	C1—C6—C7	118.9 (3)
O2—Cd1—C9	27.95 (7)	C8—C7—C6	126.6 (3)
O2ⁱ—Cd1—C9	112.16 (8)	C8—C7—H7	117 (2)
O3ⁱ—Cd1—C9ⁱ	115.41 (8)	C6—C7—H7	116 (2)
O3—Cd1—C9ⁱ	116.30 (8)	C7—C8—C9	122.2 (2)
O1ⁱ—Cd1—C9ⁱ	28.08 (7)	C7—C8—H8	127 (5)
O1—Cd1—C9ⁱ	90.85 (8)	C9—C8—H8	111 (5)
O2—Cd1—C9ⁱ	112.16 (8)	O2—C9—O1	120.3 (2)
O2ⁱ—Cd1—C9ⁱ	27.96 (7)	O2—C9—C8	119.0 (3)
C9—Cd1—C9ⁱ	101.50 (11)	O1—C9—C8	120.6 (2)
Cd1—O3—H3A	119 (3)	O2—C9—Cd1	61.30 (13)
Cd1—O3—H3B	123 (4)	O1—C9—Cd1	59.28 (13)
H3A—O3—H3B	112 (5)	C8—C9—Cd1	174.6 (3)
C9—O1—Cd1	92.64 (15)

Symmetry code: (i) −x+2, y, −z+2.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O3—H3A···O1ⁱⁱ	0.82 (2)	1.86 (2)	2.679 (3)	174 (4)
O3—H3B···O2ⁱⁱⁱ	0.80 (2)	1.86 (3)	2.658 (3)	171 (5)

Symmetry codes: (ii) −x+2, y−1, −z+2; (iii) −x+3/2, y−1/2, −z+2.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O3—H3A···O1ⁱ	0.82 (2)	1.86 (2)	2.679 (3)	174 (4)
O3—H3B···O2ⁱⁱ	0.80 (2)	1.86 (3)	2.658 (3)	171 (5)

Symmetry codes: (i) −x+2, y−1, −z+2; (ii) −x+3/2, y−1/2, −z+2.

Acknowledgements

This work was supported by the Songklanagarind Scholarship for Graduate Studies from Prince of Songkla University. SC would like to thank Ruthairat Nimthong for assistance in the manuscript preparation. The X-ray diffractometer at Youngstown State University was funded by NSF grant 0087210, Ohio Board of Regents grant CAP-491, and by Youngstown State University.

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