metal-organic compounds
Poly[bis(μ2-benzyloxyacetato-κ3O,O′:O′′)cadmium(II)]
aCollege of Chemistry and Chemical Technology, Daqing Petroleum Institute, Daqing 163318, People's Republic of China, and bDepartment of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia
*Correspondence e-mail: seikweng@um.edu.my
The title cadmium derivative of benzyloxyacetic acid, [Cd(C9H9O3)2]n, exists as a μ2-carboxylate-bridged layer network. Two benzyloxyacetate units each chelate the metal through a carboxylate as well as through the ether O atoms; the metal is also coordinated by the double-bond carbonyl O atom of two adjacent benzyloxyacetate units in an octahedral geometry. The metal atom lies on a special position of 2 The phenyl group is disordered equally over two positions.
Related literature
There are no crystallographic examples of metal benzyloxyacetates although there are many examples of metal aryloxyacetates. For mononuclear diaquadi(phenoxyacetato)cadmium, see: Mak et al. (1985).
Experimental
Crystal data
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Data collection: APEX2 (Bruker, 2006); cell SAINT (Bruker, 2006); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: X-SEED (Barbour, 2001); OLEX (Dolomanov et al., 2003); software used to prepare material for publication: SHELXL97.
Supporting information
10.1107/S1600536808010799/sg2235sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536808010799/sg2235Isup2.hkl
Cadmium dinitrate tetrahydrate (0.31 g, 1 mmol) and 2,2'-bipyridine (0.16 g, 1 mmol) were added to a hot aqueous solution of benzyloxyacetic acid (0.17 g, 1 mmol). The pH of the solution was adjusted to 6 with 0.1 M sodium hydroxide. The solution was allowed to evaporate at room temperature. Colorless single crystals are separated from the filtered solution after several days.
Hydrogen atoms were treated as riding, with C–H = 0.93 to 0.97 Å and were included in the
with U(H) set to 1.2 times Ueq(C). The phenyl ring is disordered over two sites; the occupancy could not be refined, and each component was arbitrarily assigned 0.5 occupancy. The ring was refined as a rigid hexagon; the temperature factors of the primed atoms were constrained to those of the unprimed ones. The anisotropic temperature factors of the ring were retrained to be nearly isotropic. The C3–C4 and C3–C4' distances were restrained to within 0.01 Å of each other.The final difference Fourier map had a large peak at about 1 Å from Cd1.
Data collection: APEX2 (Bruker, 2006); cell
SAINT (Bruker, 2006); data reduction: SAINT (Bruker, 2006); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: X-SEED (Barbour, 2001); OLEX (Dolomanov et al., 2003); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).Fig. 1. Thermal displacement ellipsoid plot (Barbour, 2001) illustrating the coordination geometry of Cd in [Cd(C9H9O3)2]n. Displacement ellipsoids are drawn at the 50% probability level and H atoms as spheres of arbitrary radii. | |
Fig. 2. OLEX (Dolomanov et al., 2003) representation of the layer structure. |
[Cd(C9H9O3)2] | F(000) = 444 |
Mr = 442.72 | Dx = 1.575 Mg m−3 |
Orthorhombic, P21212 | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: P 2 2ab | Cell parameters from 2270 reflections |
a = 6.7430 (2) Å | θ = 2.6–23.6° |
b = 8.9449 (2) Å | µ = 1.20 mm−1 |
c = 15.4736 (4) Å | T = 295 K |
V = 933.30 (4) Å3 | Block, colorless |
Z = 2 | 0.33 × 0.13 × 0.04 mm |
Bruker APEXII diffractometer | 1639 independent reflections |
Radiation source: fine-focus sealed tube | 1483 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.039 |
ϕ and ω scans | θmax = 25.0°, θmin = 1.3° |
Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | h = −7→7 |
Tmin = 0.693, Tmax = 0.954 | k = −10→9 |
5780 measured reflections | l = −18→17 |
Refinement on F2 | Secondary atom site location: difference Fourier map |
Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
R[F2 > 2σ(F2)] = 0.044 | H-atom parameters constrained |
wR(F2) = 0.125 | w = 1/[σ2(Fo2) + (0.0833P)2] where P = (Fo2 + 2Fc2)/3 |
S = 1.09 | (Δ/σ)max = 0.001 |
1639 reflections | Δρmax = 2.22 e Å−3 |
108 parameters | Δρmin = −0.88 e Å−3 |
37 restraints | Absolute structure: Flack (1983), 501 Friedel pairs |
Primary atom site location: structure-invariant direct methods | Absolute structure parameter: 0.03 (8) |
[Cd(C9H9O3)2] | V = 933.30 (4) Å3 |
Mr = 442.72 | Z = 2 |
Orthorhombic, P21212 | Mo Kα radiation |
a = 6.7430 (2) Å | µ = 1.20 mm−1 |
b = 8.9449 (2) Å | T = 295 K |
c = 15.4736 (4) Å | 0.33 × 0.13 × 0.04 mm |
Bruker APEXII diffractometer | 1639 independent reflections |
Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | 1483 reflections with I > 2σ(I) |
Tmin = 0.693, Tmax = 0.954 | Rint = 0.039 |
5780 measured reflections |
R[F2 > 2σ(F2)] = 0.044 | H-atom parameters constrained |
wR(F2) = 0.125 | Δρmax = 2.22 e Å−3 |
S = 1.09 | Δρmin = −0.88 e Å−3 |
1639 reflections | Absolute structure: Flack (1983), 501 Friedel pairs |
108 parameters | Absolute structure parameter: 0.03 (8) |
37 restraints |
x | y | z | Uiso*/Ueq | Occ. (<1) | |
Cd1 | 1.0000 | 1.0000 | 0.01184 (4) | 0.0405 (3) | |
O1 | 1.2315 (7) | 0.8208 (5) | 0.0358 (3) | 0.0481 (12) | |
O2 | 1.2948 (7) | 0.5938 (5) | 0.0869 (3) | 0.0495 (12) | |
O3 | 0.9048 (6) | 0.8466 (5) | 0.1304 (3) | 0.0443 (11) | |
C1 | 1.1913 (10) | 0.7127 (7) | 0.0819 (4) | 0.0385 (15) | |
C2 | 1.0100 (14) | 0.7103 (6) | 0.1367 (4) | 0.0427 (13) | |
H2A | 0.9248 | 0.6287 | 0.1186 | 0.051* | |
H2B | 1.0472 | 0.6931 | 0.1964 | 0.051* | |
C3 | 0.7017 (11) | 0.8363 (9) | 0.1615 (5) | 0.059 (2) | |
H3A | 0.6423 | 0.7463 | 0.1381 | 0.070* | |
H3B | 0.6276 | 0.9209 | 0.1392 | 0.070* | |
C4 | 0.680 (3) | 0.834 (2) | 0.2552 (5) | 0.060 (3) | 0.50 |
C5 | 0.567 (2) | 0.7180 (17) | 0.2895 (9) | 0.100 (5) | 0.50 |
H5 | 0.5061 | 0.6494 | 0.2529 | 0.119* | 0.50 |
C6 | 0.545 (3) | 0.705 (2) | 0.3785 (10) | 0.124 (6) | 0.50 |
H6 | 0.4689 | 0.6276 | 0.4014 | 0.149* | 0.50 |
C7 | 0.636 (3) | 0.807 (2) | 0.4332 (5) | 0.127 (8) | 0.50 |
H7 | 0.6206 | 0.7986 | 0.4927 | 0.152* | 0.50 |
C8 | 0.749 (4) | 0.923 (2) | 0.3989 (9) | 0.135 (5) | 0.50 |
H8 | 0.8096 | 0.9915 | 0.4355 | 0.162* | 0.50 |
C9 | 0.771 (4) | 0.936 (2) | 0.3099 (10) | 0.108 (5) | 0.50 |
H9 | 0.8468 | 1.0133 | 0.2870 | 0.130* | 0.50 |
C4' | 0.704 (3) | 0.8030 (19) | 0.2550 (5) | 0.060 (3) | 0.50 |
C5' | 0.682 (3) | 0.6579 (16) | 0.2856 (9) | 0.100 (5) | 0.50 |
H5' | 0.6602 | 0.5798 | 0.2471 | 0.119* | 0.50 |
C6' | 0.691 (3) | 0.6296 (17) | 0.3739 (10) | 0.124 (6) | 0.50 |
H6' | 0.6755 | 0.5325 | 0.3943 | 0.149* | 0.50 |
C7' | 0.723 (3) | 0.746 (2) | 0.4315 (6) | 0.127 (8) | 0.50 |
H7' | 0.7288 | 0.7273 | 0.4905 | 0.152* | 0.50 |
C8' | 0.745 (4) | 0.891 (2) | 0.4009 (9) | 0.135 (5) | 0.50 |
H8' | 0.7667 | 0.9695 | 0.4395 | 0.162* | 0.50 |
C9' | 0.736 (4) | 0.9198 (16) | 0.3127 (10) | 0.108 (5) | 0.50 |
H9' | 0.7514 | 1.0168 | 0.2922 | 0.130* | 0.50 |
U11 | U22 | U33 | U12 | U13 | U23 | |
Cd1 | 0.0336 (4) | 0.0237 (3) | 0.0641 (4) | 0.0012 (3) | 0.000 | 0.000 |
O1 | 0.041 (3) | 0.033 (3) | 0.070 (3) | 0.010 (2) | 0.012 (2) | 0.006 (3) |
O2 | 0.048 (3) | 0.030 (2) | 0.070 (3) | 0.010 (2) | 0.006 (2) | 0.003 (2) |
O3 | 0.037 (2) | 0.028 (2) | 0.068 (3) | 0.0084 (19) | 0.012 (2) | 0.008 (2) |
C1 | 0.036 (4) | 0.027 (3) | 0.053 (4) | 0.006 (3) | −0.003 (3) | −0.005 (3) |
C2 | 0.037 (3) | 0.028 (3) | 0.063 (3) | 0.007 (4) | −0.006 (6) | 0.004 (2) |
C3 | 0.033 (4) | 0.056 (4) | 0.087 (6) | 0.016 (4) | 0.015 (4) | 0.008 (4) |
C4 | 0.054 (6) | 0.054 (6) | 0.072 (5) | 0.009 (6) | 0.014 (4) | −0.012 (4) |
C5 | 0.109 (10) | 0.098 (9) | 0.092 (7) | 0.006 (7) | 0.031 (7) | 0.016 (7) |
C6 | 0.126 (11) | 0.126 (9) | 0.120 (8) | −0.006 (8) | 0.019 (8) | 0.020 (8) |
C7 | 0.132 (11) | 0.134 (11) | 0.114 (9) | 0.012 (9) | 0.018 (8) | −0.004 (8) |
C8 | 0.134 (9) | 0.152 (9) | 0.119 (8) | −0.005 (8) | −0.001 (7) | −0.031 (7) |
C9 | 0.091 (9) | 0.122 (8) | 0.112 (7) | −0.008 (7) | 0.007 (6) | −0.025 (6) |
C4' | 0.054 (6) | 0.054 (6) | 0.072 (5) | 0.009 (6) | 0.014 (4) | −0.012 (4) |
C5' | 0.109 (10) | 0.098 (9) | 0.092 (7) | 0.006 (7) | 0.031 (7) | 0.016 (7) |
C6' | 0.126 (11) | 0.126 (9) | 0.120 (8) | −0.006 (8) | 0.019 (8) | 0.020 (8) |
C7' | 0.132 (11) | 0.134 (11) | 0.114 (9) | 0.012 (9) | 0.018 (8) | −0.004 (8) |
C8' | 0.134 (9) | 0.152 (9) | 0.119 (8) | −0.005 (8) | −0.001 (7) | −0.031 (7) |
C9' | 0.091 (9) | 0.122 (8) | 0.112 (7) | −0.008 (7) | 0.007 (6) | −0.025 (6) |
Cd1—O1 | 2.268 (4) | C5—C6 | 1.3900 |
Cd1—O1i | 2.268 (4) | C5—H5 | 0.9300 |
Cd1—O2ii | 2.226 (5) | C6—C7 | 1.3900 |
Cd1—O2iii | 2.226 (5) | C6—H6 | 0.9300 |
Cd1—O3 | 2.379 (4) | C7—C8 | 1.3900 |
Cd1—O3i | 2.379 (4) | C7—H7 | 0.9300 |
O1—C1 | 1.232 (8) | C8—C9 | 1.3900 |
O2—C1 | 1.274 (7) | C8—H8 | 0.9300 |
O2—Cd1iv | 2.226 (5) | C9—H9 | 0.9300 |
O3—C2 | 1.414 (7) | C4'—C5' | 1.3900 |
O3—C3 | 1.455 (8) | C4'—C9' | 1.3900 |
C1—C2 | 1.488 (11) | C5'—C6' | 1.3900 |
C2—H2A | 0.9700 | C5'—H5' | 0.9300 |
C2—H2B | 0.9700 | C6'—C7' | 1.3900 |
C3—C4 | 1.457 (11) | C6'—H6' | 0.9300 |
C3—C4' | 1.477 (11) | C7'—C8' | 1.3900 |
C3—H3A | 0.9700 | C7'—H7' | 0.9300 |
C3—H3B | 0.9700 | C8'—C9' | 1.3900 |
C4—C5 | 1.3900 | C8'—H8' | 0.9300 |
C4—C9 | 1.3900 | C9'—H9' | 0.9300 |
O1—Cd1—O1i | 161.2 (3) | H3A—C3—H3B | 107.5 |
O1—Cd1—O2ii | 105.9 (2) | C5—C4—C9 | 120.0 |
O1—Cd1—O2iii | 87.2 (2) | C5—C4—C3 | 116.6 (12) |
O1—Cd1—O3 | 69.6 (2) | C9—C4—C3 | 123.4 (12) |
O1—Cd1—O3i | 95.5 (2) | C6—C5—C4 | 120.0 |
O1i—Cd1—O2ii | 87.2 (2) | C6—C5—H5 | 120.0 |
O1i—Cd1—O2iii | 105.9 (2) | C4—C5—H5 | 120.0 |
O1i—Cd1—O3i | 69.6 (2) | C5—C6—C7 | 120.0 |
O1i—Cd1—O3 | 95.5 (2) | C5—C6—H6 | 120.0 |
O2ii—Cd1—O2iii | 93.3 (3) | C7—C6—H6 | 120.0 |
O2ii—Cd1—O3 | 98.3 (2) | C6—C7—C8 | 120.0 |
O2ii—Cd1—O3i | 156.2 (2) | C6—C7—H7 | 120.0 |
O2iii—Cd1—O3 | 156.2 (2) | C8—C7—H7 | 120.0 |
O2iii—Cd1—O3i | 98.3 (2) | C9—C8—C7 | 120.0 |
O3—Cd1—O3i | 79.1 (2) | C9—C8—H8 | 120.0 |
C1—O1—Cd1 | 119.9 (4) | C7—C8—H8 | 120.0 |
C1—O2—Cd1iv | 127.8 (5) | C8—C9—C4 | 120.0 |
C2—O3—C3 | 113.3 (6) | C8—C9—H9 | 120.0 |
C2—O3—Cd1 | 114.5 (4) | C4—C9—H9 | 120.0 |
C3—O3—Cd1 | 123.1 (4) | C5'—C4'—C9' | 120.0 |
O1—C1—O2 | 124.7 (6) | C5'—C4'—C3 | 121.4 (12) |
O1—C1—C2 | 121.5 (5) | C9'—C4'—C3 | 118.6 (12) |
O2—C1—C2 | 113.8 (6) | C6'—C5'—C4' | 120.0 |
O3—C2—C1 | 111.1 (5) | C6'—C5'—H5' | 120.0 |
O3—C2—H2A | 109.4 | C4'—C5'—H5' | 120.0 |
C1—C2—H2A | 109.4 | C5'—C6'—C7' | 120.0 |
O3—C2—H2B | 109.4 | C5'—C6'—H6' | 120.0 |
C1—C2—H2B | 109.4 | C7'—C6'—H6' | 120.0 |
H2A—C2—H2B | 108.0 | C6'—C7'—C8' | 120.0 |
O3—C3—C4 | 115.1 (10) | C6'—C7'—H7' | 120.0 |
O3—C3—C4' | 109.0 (11) | C8'—C7'—H7' | 120.0 |
O3—C3—H3A | 108.5 | C9'—C8'—C7' | 120.0 |
C4—C3—H3A | 108.5 | C9'—C8'—H8' | 120.0 |
C4'—C3—H3A | 101.8 | C7'—C8'—H8' | 120.0 |
O3—C3—H3B | 108.5 | C8'—C9'—C4' | 120.0 |
C4—C3—H3B | 108.5 | C8'—C9'—H9' | 120.0 |
C4'—C3—H3B | 120.9 | C4'—C9'—H9' | 120.0 |
O2ii—Cd1—O1—C1 | −78.1 (6) | Cd1—O3—C2—C1 | 15.2 (7) |
O2iii—Cd1—O1—C1 | −170.7 (5) | O1—C1—C2—O3 | −2.7 (10) |
O1i—Cd1—O1—C1 | 54.5 (5) | O2—C1—C2—O3 | 178.2 (6) |
O3i—Cd1—O1—C1 | 91.2 (6) | C2—O3—C3—C4 | 76.0 (10) |
O3—Cd1—O1—C1 | 15.0 (5) | Cd1—O3—C3—C4 | −139.0 (9) |
O2ii—Cd1—O3—C2 | 88.3 (5) | C2—O3—C3—C4' | 64.4 (10) |
O2iii—Cd1—O3—C2 | −29.9 (7) | Cd1—O3—C3—C4' | −150.7 (8) |
O1i—Cd1—O3—C2 | 176.3 (5) | O3—C3—C4—C5 | −128.2 (12) |
O1—Cd1—O3—C2 | −15.6 (4) | C4'—C3—C4—C5 | −65 (6) |
O3i—Cd1—O3—C2 | −115.7 (5) | O3—C3—C4—C9 | 49.7 (12) |
O2ii—Cd1—O3—C3 | −56.3 (6) | C4'—C3—C4—C9 | 113 (7) |
O2iii—Cd1—O3—C3 | −174.5 (5) | C3—C4—C5—C6 | 178.0 (15) |
O1i—Cd1—O3—C3 | 31.7 (5) | C3—C4—C9—C8 | −177.8 (16) |
O1—Cd1—O3—C3 | −160.2 (6) | O3—C3—C4'—C5' | −97.6 (15) |
O3i—Cd1—O3—C3 | 99.7 (5) | C4—C3—C4'—C5' | 141 (8) |
Cd1—O1—C1—O2 | 166.5 (5) | O3—C3—C4'—C9' | 80.5 (10) |
Cd1—O1—C1—C2 | −12.5 (9) | C4—C3—C4'—C9' | −41 (7) |
Cd1iv—O2—C1—O1 | −25.2 (10) | C3—C4'—C5'—C6' | 178.1 (17) |
Cd1iv—O2—C1—C2 | 153.9 (4) | C3—C4'—C9'—C8' | −178.1 (17) |
C3—O3—C2—C1 | 163.3 (6) |
Symmetry codes: (i) −x+2, −y+2, z; (ii) x−1/2, −y+3/2, −z; (iii) −x+5/2, y+1/2, −z; (iv) x+1/2, −y+3/2, −z. |
Experimental details
Crystal data | |
Chemical formula | [Cd(C9H9O3)2] |
Mr | 442.72 |
Crystal system, space group | Orthorhombic, P21212 |
Temperature (K) | 295 |
a, b, c (Å) | 6.7430 (2), 8.9449 (2), 15.4736 (4) |
V (Å3) | 933.30 (4) |
Z | 2 |
Radiation type | Mo Kα |
µ (mm−1) | 1.20 |
Crystal size (mm) | 0.33 × 0.13 × 0.04 |
Data collection | |
Diffractometer | Bruker APEXII diffractometer |
Absorption correction | Multi-scan (SADABS; Sheldrick, 1996) |
Tmin, Tmax | 0.693, 0.954 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 5780, 1639, 1483 |
Rint | 0.039 |
(sin θ/λ)max (Å−1) | 0.594 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.044, 0.125, 1.09 |
No. of reflections | 1639 |
No. of parameters | 108 |
No. of restraints | 37 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 2.22, −0.88 |
Absolute structure | Flack (1983), 501 Friedel pairs |
Absolute structure parameter | 0.03 (8) |
Computer programs: APEX2 (Bruker, 2006), SAINT (Bruker, 2006), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), X-SEED (Barbour, 2001); OLEX (Dolomanov et al., 2003).
Cd1—O1 | 2.268 (4) | Cd1—O2iii | 2.226 (5) |
Cd1—O1i | 2.268 (4) | Cd1—O3 | 2.379 (4) |
Cd1—O2ii | 2.226 (5) | Cd1—O3i | 2.379 (4) |
O1—Cd1—O1i | 161.2 (3) | O1i—Cd1—O3 | 95.5 (2) |
O1—Cd1—O2ii | 105.9 (2) | O2ii—Cd1—O2iii | 93.3 (3) |
O1—Cd1—O2iii | 87.2 (2) | O2ii—Cd1—O3 | 98.3 (2) |
O1—Cd1—O3 | 69.6 (2) | O2ii—Cd1—O3i | 156.2 (2) |
O1—Cd1—O3i | 95.5 (2) | O2iii—Cd1—O3 | 156.2 (2) |
O1i—Cd1—O2ii | 87.2 (2) | O2iii—Cd1—O3i | 98.3 (2) |
O1i—Cd1—O2iii | 105.9 (2) | O3—Cd1—O3i | 79.1 (2) |
O1i—Cd1—O3i | 69.6 (2) |
Symmetry codes: (i) −x+2, −y+2, z; (ii) x−1/2, −y+3/2, −z; (iii) −x+5/2, y+1/2, −z. |
Acknowledgements
The authors thank Daqing Petroleum Institute and the University of Malaya for generously supporting this study.
References
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The crystal structures of a large number of metal derivatives of aryloxyacetic acids have been reported; in some structures, the ether oxygen also engages in bonding so that the carboxylate unit functions both as a chelate as well as a bridge. The cadmium derivative of phenyoxyacetic acid exists as a diaqua, carboxylate-chelated compound. The carboxyl –CO2 portion engages in chelation instead (Mak et al., 1985). The title cadmium analog has a benzyl group in place of the phenyl group, which is probably less crowded; this feature permits the ether linkage to bind to the metal atom. The compound (Scheme I) is an anhydrous compound; the carboxylate group chelates to the metal atom. It also bridges adjacent metal atoms (Fig. 1); the bridges lead to the formation of a layer motif (Fig. 2).