supplementary materials


lh5627 scheme

Acta Cryst. (2013). E69, i45-i46    [ doi:10.1107/S1600536813018187 ]

Tetraammine(carbonato-[kappa]2O,O')cobalt(III) perchlorate

S. C. Mohan, S. J. Jenniefer, P. T. Muthiah and K. Jothivenkatachalam

Abstract top

In the title complex, [Co(CO3)(NH3)4]ClO4, both the cation and anion lie on a mirror plane. The CoIII ion is coordinated by two NH3 ligands and a chelating carbonato ligand in the equatorial sites and by two NH3 groups in the axial sites, forming a distorted octahedral geometry. In the crystal, N-H...O hydrogen bonds connect the anions and cations, forming a three-dimensional network.

Comment top

Cobalt(III) ammine complexes are well known and were widely studied by Werner (1908). In aqueous medium, the chelated ring of a bicarbonate complex is opened and protonation occurs due to hydrolysis which leads to instability. The less stability of a carbonato complex in acidic aqueous medium not only leads to protonation but also makes a site for metallation (McClintock et al., 2008; Cavigliasso et al., 2008). The carbanato complex also plays a vital role in photocleavage of proteins with high preference and it assists the new models of transition metal complexes for the photocleavage (Kumar & Thota, 2005). The P—O bonds present in the phosphodiester of DNA have been cleaved hydrolytically by the imitative of chelated carbonato complexes (Xu et al., 2009). Recently the carbonate radical generation by photochemical reaction of carbonatopentaamminecobalt(III) complex was also reported (Busset et al., 2007). The photochemical reactions of carboxylatopentamminecobalt(III) complexes lead to the reduction of metal centre and the formation of oxidized ligands, which may lead to the synthesis of value added products (Palaniappan et al., 2001; Jothivenkatachalam et al., 2013).

The crystal structure of the title complex is composed of one [CoCO3(NH3)4]+ cation and a ClO4- anion in a 1:1 molar ratio. A mirror plane bisects the cation as well as the perchlorate anion, hence half a cation and an anion form the asymmetric unit. The molecular structure of the title complex is shown in Fig. 1. The CoIII ion is coordinated by two NH3 ligands and a chelating carbanato ligand equatorially, by two NH3 groups axially. Unlike other d6 octahedral Co(II) complexes the title complex shows a distortion from ideal octahedral geometry. This can be noted by the deviation of O1—Co—O1i bond angle of 68.41 (7)° from the ideal octahedral bond angle of 90°. This is due to the steric restriction of the carbanato ligand in the formation of four membered chelate ring. The observed O—Co—O bond angle is similar to those observed in related [Co(CO3)(N)4]+ species (Kim et al., 1998; Massoud et al., 2000). The chelating CO32- has a slight influence on the N1—Co—N1i bond angle trans to the O1—Co—O1i angle. The N1—Co—N1i bond angle is 94.22 (8)°. The Co—N bond distances observed for the complex under investigation is similar to those reported earlier [CoCO3(L2)]ClO4, [Co(NH3)2(NO2)4]-, [Co(NH3)6]3+, (Massoud et al., 2000; Sharma et al., 2004a,b; Sharma et al., 2005a,b). In the crystal, N—H···O hydrogen bonds connect anions and cations to form a three-dimensional network (Fig. 2).

Related literature top

For background to cobalt(III)–ammine complexes, see: Werner (1908) and to cobalt–carbonato complexes, see: McClintock et al. (2008); Cavigliasso et al. (2008). For their biological applications, see: Kumar & Thota (2005); Xu et al. (2009). For the chemistry of carbonatopentaamminecobalt(III) and carboxylatopentamminecobalt(III) complexes, see: Busset et al. (2007); Palaniappan et al. (2001); Jothivenkatachalam et al. (2013). For related CoIII complexes, see: Kim et al. (1998); Massoud et al. (2000); Sharma et al. (2004a,b, 2005a,b).

Experimental top

Carbonatotetramminecobalt(III) perchlorate was synthesized by the treatment of sodium bicarbonate with aquapentaamminecobalt(III) perchlorate dissolved in small amount of hot water. The pH of the reaction mixture is adjusted to pH 8 by varying sodium bicarbonate and refluxed at 333K for 4 h and kept in cool place. The purple colored carbonatotetramminecobalt(III) perchlorate precipitate then settled. The resulting solution was filtered and was dissolved in minimum amount of hot water, and then allowed to crystallize by slow evaporation at ambient temperature. Fine purple crystals of X-ray quality separated out after one week. These were filtered, washed with ethanol, acetone and air-dried.

Refinement top

The H atoms attached to N3 and N4 were located from a difference Fourier map and were refined freely. The H atoms attached to N1 were placed in geometrically idealized positions and constrained to ride on their parent atom, with N—H distance of 0.89 Å, and with Uiso(H) set at 1.5Ueq(N).

Computing details top

Data collection: APEX2 (Bruker, 2008); cell refinement: SAINT (Bruker, 2008); data reduction: SAINT (Bruker, 2008); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: POV-RAY (Persistence of Vision Team, 2004) and PLATON (Spek, 2009); software used to prepare material for publication: PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound, with anisotropic displacement ellipsoids drawn at 50% probability level [Symmetry code: (i) x, -y+1/2, z].
[Figure 2] Fig. 2. The packing of the complex viewed along the c axis, showing N—H···O hydrogen bonds as dashed lines.
Tetraammine(carbonato-κ2O,O')cobalt(III) perchlorate top
Crystal data top
[Co(CO3)(NH3)4]ClO4F(000) = 584
Mr = 286.53Dx = 1.912 Mg m3
Orthorhombic, PnmaMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ac 2nCell parameters from 1947 reflections
a = 17.8961 (5) Åθ = 2.3–33.0°
b = 8.0768 (2) ŵ = 2.01 mm1
c = 6.8871 (2) ÅT = 296 K
V = 995.48 (5) Å3Plate, purple
Z = 40.09 × 0.08 × 0.07 mm
Data collection top
Bruker SMART APEXII CCD area-detector
diffractometer
1947 independent reflections
Radiation source: fine-focus sealed tube1565 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.032
φ and ω scansθmax = 33.0°, θmin = 2.3°
Absorption correction: multi-scan
(SADABS; Bruker, 2008)
h = 2727
Tmin = 0.951, Tmax = 0.962k = 1112
12900 measured reflectionsl = 1010
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.042Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.153H atoms treated by a mixture of independent and constrained refinement
S = 1.15 w = 1/[σ2(Fo2) + (0.1P)2]
where P = (Fo2 + 2Fc2)/3
1947 reflections(Δ/σ)max < 0.001
91 parametersΔρmax = 1.06 e Å3
0 restraintsΔρmin = 0.75 e Å3
Crystal data top
[Co(CO3)(NH3)4]ClO4V = 995.48 (5) Å3
Mr = 286.53Z = 4
Orthorhombic, PnmaMo Kα radiation
a = 17.8961 (5) ŵ = 2.01 mm1
b = 8.0768 (2) ÅT = 296 K
c = 6.8871 (2) Å0.09 × 0.08 × 0.07 mm
Data collection top
Bruker SMART APEXII CCD area-detector
diffractometer
1947 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2008)
1565 reflections with I > 2σ(I)
Tmin = 0.951, Tmax = 0.962Rint = 0.032
12900 measured reflectionsθmax = 33.0°
Refinement top
R[F2 > 2σ(F2)] = 0.042H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.153Δρmax = 1.06 e Å3
S = 1.15Δρmin = 0.75 e Å3
1947 reflectionsAbsolute structure: ?
91 parametersAbsolute structure parameter: ?
0 restraintsRogers parameter: ?
Special details top

Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell e.s.d.'s are taken into account in the estimation of distances, angles and torsion angles

Refinement. Refinement on F2 for ALL reflections except those flagged by the user for potential systematic errors. Weighted R-factors wR and all goodnesses of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The observed criterion of F2 > σ(F2) is used only for calculating -R-factor-obs 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 (Å2) top
xyzUiso*/Ueq
Co10.07671 (2)0.250000.88852 (5)0.0258 (1)
O10.05126 (10)0.1164 (2)1.10933 (19)0.0324 (5)
O20.01415 (17)0.250001.3801 (3)0.0486 (9)
N10.09597 (12)0.0723 (2)0.7015 (3)0.0362 (5)
N30.02722 (17)0.250000.8052 (4)0.0328 (8)
N40.18057 (18)0.250000.9753 (5)0.0380 (9)
C10.03851 (18)0.250001.2100 (4)0.0319 (8)
Cl20.27539 (5)0.250000.48795 (14)0.0426 (3)
O30.3348 (3)0.250000.3518 (8)0.0950 (17)
O40.2027 (3)0.250000.4051 (6)0.149 (4)
O50.2799 (3)0.1123 (4)0.6072 (7)0.131 (2)
H1A0.145000.056200.691000.0540*
H1B0.077400.100500.586200.0540*
H1C0.074300.020600.742200.0540*
H20.1869 (18)0.174 (4)1.035 (5)0.052 (10)*
H30.209 (3)0.250000.904 (8)0.062 (19)*
H40.0472 (17)0.171 (3)0.843 (4)0.032 (7)*
H50.029 (2)0.250000.686 (6)0.023 (8)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Co10.0320 (3)0.0241 (2)0.0213 (2)0.00000.0021 (1)0.0000
O10.0417 (9)0.0285 (8)0.0269 (7)0.0032 (7)0.0017 (5)0.0027 (5)
O20.0462 (14)0.077 (2)0.0227 (10)0.00000.0028 (8)0.0000
N10.0450 (10)0.0319 (9)0.0318 (8)0.0014 (8)0.0007 (8)0.0035 (7)
N30.0368 (13)0.0343 (14)0.0272 (12)0.00000.0029 (10)0.0000
N40.0369 (14)0.0407 (18)0.0364 (14)0.00000.0037 (12)0.0000
C10.0336 (13)0.0392 (16)0.0230 (11)0.00000.0044 (10)0.0000
Cl20.0418 (4)0.0377 (5)0.0482 (5)0.00000.0064 (3)0.0000
O30.102 (3)0.068 (3)0.115 (3)0.00000.076 (3)0.0000
O40.066 (3)0.324 (11)0.056 (3)0.00000.0011 (19)0.0000
O50.162 (4)0.0684 (19)0.161 (4)0.041 (2)0.070 (3)0.054 (2)
Geometric parameters (Å, º) top
Co1—O11.9195 (15)O2—C11.250 (4)
Co1—N11.9590 (19)N1—H1A0.8900
Co1—N31.947 (3)N1—H1B0.8900
Co1—N41.952 (3)N1—H1C0.8900
Co1—O1i1.9195 (15)N3—H40.78 (3)
Co1—N1i1.9590 (19)N3—H50.82 (4)
Cl2—O5i1.385 (4)N3—H4i0.78 (3)
Cl2—O31.418 (6)N4—H30.71 (5)
Cl2—O41.421 (5)N4—H2i0.75 (3)
Cl2—O51.385 (4)N4—H20.75 (3)
O1—C11.303 (2)
Co1···O2ii3.676 (2)N3···O12.743 (3)
Co1···O1iii3.7420 (17)N3···N1i2.726 (3)
Co1···O1iv3.7420 (17)N3···O2ii3.020 (4)
Co1···O2v3.676 (2)N3···N12.726 (3)
Cl2···H1Ai3.1400N3···C13.026 (4)
Cl2···H1A3.1400N4···N1i2.812 (4)
Cl2···H33.10 (5)N4···O12.715 (3)
Cl2···H33.10 (5)N4···O4vii2.987 (5)
O1···O22.255 (2)N4···O1i2.715 (3)
O1···N3iv3.0478 (18)N4···O5xiv3.145 (4)
O1···N32.743 (3)N4···N12.812 (4)
O1···Co1vi3.7420 (17)N4···C13.013 (5)
O1···N12.942 (2)N4···O4viii2.987 (5)
O1···N42.715 (3)N4···O5xii3.145 (4)
O1···O1iv3.028 (2)N1···H52.66 (3)
O1···N3vi3.0478 (18)N1···H32.85 (5)
O1···O1i2.158 (2)N1···H42.86 (3)
O1···Co1iv3.7420 (17)N1···H1Bi2.7800
O2···N1vii3.017 (3)N1···H22.93 (3)
O2···N3vii3.020 (4)N3···H1Ci2.8800
O2···Co1viii3.676 (2)N3···H1B2.6900
O2···O1i2.255 (2)N3···H1C2.8800
O2···N3viii3.020 (4)N3···H1Bi2.6900
O2···Co1vii3.676 (2)N4···H1Ai2.5900
O2···O12.255 (2)N4···H1A2.5900
O2···N1viii3.017 (3)C1···O4viii3.231 (6)
O3···N1ix3.063 (3)C1···N33.026 (4)
O3···N1x3.063 (3)C1···N43.013 (5)
O4···N1i3.143 (5)C1···O4vii3.231 (6)
O4···N4ii2.987 (5)C1···H22.98 (3)
O4···C1v3.231 (6)C1···H1Civ2.7600
O4···C1ii3.231 (6)C1···H43.03 (3)
O4···N4v2.987 (5)C1···H1Bviii2.9400
O4···N13.143 (5)C1···H4i3.03 (3)
O5···N4xi3.145 (4)C1···H1Ciii2.7600
O5···N4ix3.145 (4)C1···H1Bvii2.9400
O1···H1Civ2.5900C1···H2i2.98 (3)
O1···H22.52 (3)H1A···H32.4300
O1···H4iv2.35 (2)H1A···O3xii2.7300
O1···H42.58 (3)H1A···O3xiii2.7300
O1···H1C2.7900H1A···O52.5200
O2···H1Civ2.5800H1A···Cl23.1400
O2···H5viii2.24 (4)H1A···O42.7200
O2···H1Bvii2.1800H1A···Cl23.1400
O2···H1Ciii2.5800H1A···O42.7200
O2···H5vii2.24 (4)H1B···O2v2.1800
O2···H1Bviii2.1800H1B···C1ii2.9400
O3···H1Ax2.7300H1B···H52.3600
O3···H1Aix2.7300H1B···O2ii2.1800
O3···H1Cix2.5800H1B···O42.8400
O3···H1Cx2.5800H1B···O42.8400
O4···H1A2.7200H1B···C1v2.9400
O4···H2ii2.64 (3)H1B···H1Bi2.4100
O4···H1B2.8400H1C···C1vi2.7600
O4···H2v2.64 (3)H1C···O1iv2.5900
O4···H1Ai2.7200H1C···O2iv2.5800
O4···H1Bi2.8400H1C···O3xii2.5800
O5···H32.65 (5)H1C···O2vi2.5800
O5···H1A2.5200H1C···C1iv2.7600
O5···H2ix2.44 (3)H1C···O3xiii2.5800
O5···H32.65 (5)H2···O4viii2.64 (3)
N1···O12.942 (2)H2···O4vii2.64 (3)
N1···O43.143 (5)H2···O5xii2.44 (3)
N1···N1i2.871 (2)H3···Cl23.10 (5)
N1···N32.726 (3)H3···O52.65 (5)
N1···O2ii3.017 (3)H3···H1A2.4300
N1···O43.143 (5)H3···Cl23.10 (5)
N1···O3xii3.063 (3)H3···O5i2.65 (5)
N1···N42.812 (4)H3···H1Ai2.4300
N1···O2v3.017 (3)H4···O1iv2.35 (2)
N1···O3xiii3.063 (3)H5···O2v2.24 (4)
N3···O2v3.020 (4)H5···H1Bi2.3600
N3···O1iv3.0478 (18)H5···H1B2.3600
N3···O1i2.743 (3)H5···O2ii2.24 (4)
N3···O1iii3.0478 (18)
O1—Co1—N198.67 (7)Co1—O1—C189.86 (13)
O1—Co1—N390.39 (9)Co1—N1—H1C110.00
O1—Co1—N489.05 (10)Co1—N1—H1B109.00
O1—Co1—C134.21 (5)H1A—N1—H1C109.00
O1—Co1—O1i68.41 (7)H1B—N1—H1C110.00
O1—Co1—N1i167.04 (7)H1A—N1—H1B109.00
N1—Co1—N388.53 (8)Co1—N1—H1A110.00
N1—Co1—N491.94 (9)H4—N3—H4i111 (3)
N1—Co1—C1132.85 (6)H4i—N3—H5109 (2)
O1i—Co1—N1167.04 (7)H4—N3—H5109 (2)
N1—Co1—N1i94.22 (8)Co1—N3—H4i110 (2)
N3—Co1—N4179.32 (13)Co1—N3—H4110 (2)
N3—Co1—C189.99 (11)Co1—N3—H5109 (3)
O1i—Co1—N390.39 (9)H2i—N4—H3106 (3)
N1i—Co1—N388.53 (8)Co1—N4—H2i108 (2)
N4—Co1—C189.33 (13)Co1—N4—H2108 (2)
O1i—Co1—N489.05 (10)Co1—N4—H3118 (4)
N1i—Co1—N491.94 (9)H2—N4—H2i110 (4)
O1i—Co1—C134.21 (5)H2—N4—H3106 (3)
N1i—Co1—C1132.85 (6)Co1—C1—O2176.8 (3)
O1i—Co1—N1i98.67 (7)Co1—C1—O1i55.93 (12)
O5—Cl2—O5i106.9 (3)O1—C1—O1i111.9 (2)
O3—Cl2—O5110.4 (2)O1i—C1—O2124.05 (12)
O3—Cl2—O5i110.4 (2)O1—C1—O2124.05 (12)
O3—Cl2—O4114.9 (3)Co1—C1—O155.93 (12)
O4—Cl2—O5107.0 (2)
N1—Co1—O1—C1177.97 (17)N3—Co1—C1—O190.72 (15)
N3—Co1—O1—C189.40 (17)N4—Co1—C1—O189.29 (15)
N4—Co1—O1—C190.22 (17)O1i—Co1—C1—O1178.6 (3)
O1i—Co1—O1—C10.87 (16)N1i—Co1—C1—O1178.69 (14)
O1—Co1—C1—O1i178.6 (3)O1—Co1—O1i—C10.87 (16)
N1—Co1—C1—O12.7 (2)Co1—O1—C1—O2176.1 (3)
N1—Co1—C1—O1i178.69 (14)Co1—O1—C1—O1i1.3 (2)
Symmetry codes: (i) x, y+1/2, z; (ii) x, y, z1; (iii) x, y+1/2, z+2; (iv) x, y, z+2; (v) x, y+1/2, z1; (vi) x, y1/2, z+2; (vii) x, y+1/2, z+1; (viii) x, y, z+1; (ix) x+1/2, y, z1/2; (x) x+1/2, y+1/2, z1/2; (xi) x+1/2, y1/2, z1/2; (xii) x+1/2, y, z+1/2; (xiii) x+1/2, y1/2, z+1/2; (xiv) x+1/2, y+1/2, z+1/2.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1A···O50.892.523.371 (6)159
N1—H1B···O2ii0.892.183.017 (3)156
N1—H1C···O3xii0.892.583.063 (3)115
N1—H1C···O2vi0.892.583.313 (3)140
N1—H1C···O1iv0.892.593.311 (3)139
N4—H2···O5xii0.75 (3)2.44 (3)3.145 (4)158 (3)
N3—H4···O1iv0.78 (3)2.35 (2)3.0478 (18)151 (3)
N3—H5···O2ii0.82 (4)2.24 (4)3.020 (4)158 (3)
Symmetry codes: (ii) x, y, z1; (iv) x, y, z+2; (vi) x, y1/2, z+2; (xii) x+1/2, y, z+1/2.

Experimental details

Crystal data
Chemical formula[Co(CO3)(NH3)4]ClO4
Mr286.53
Crystal system, space groupOrthorhombic, Pnma
Temperature (K)296
a, b, c (Å)17.8961 (5), 8.0768 (2), 6.8871 (2)
V3)995.48 (5)
Z4
Radiation typeMo Kα
µ (mm1)2.01
Crystal size (mm)0.09 × 0.08 × 0.07
Data collection
DiffractometerBruker SMART APEXII CCD area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2008)
Tmin, Tmax0.951, 0.962
No. of measured, independent and
observed [I > 2σ(I)] reflections
12900, 1947, 1565
Rint0.032
(sin θ/λ)max1)0.766
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.042, 0.153, 1.15
No. of reflections1947
No. of parameters91
No. of restraints0
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)1.06, 0.75

Computer programs: APEX2 (Bruker, 2008), SAINT (Bruker, 2008), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), POV-RAY (Persistence of Vision Team, 2004) and PLATON (Spek, 2009), PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1A···O50.892.523.371 (6)159
N1—H1B···O2i0.892.183.017 (3)156
N1—H1C···O3ii0.892.583.063 (3)115
N1—H1C···O2iii0.892.583.313 (3)140
N1—H1C···O1iv0.892.593.311 (3)139
N4—H2···O5ii0.75 (3)2.44 (3)3.145 (4)158 (3)
N3—H4···O1iv0.78 (3)2.35 (2)3.0478 (18)151 (3)
N3—H5···O2i0.82 (4)2.24 (4)3.020 (4)158 (3)
Symmetry codes: (i) x, y, z1; (ii) x+1/2, y, z+1/2; (iii) x, y1/2, z+2; (iv) x, y, z+2.
Acknowledgements top

KJV thanks the Department of Science and Technology (DST), Government of India, New Delhi, for financial support (sanction No. SR/FT/CS-042/2008). The authors thank the DST India (FIST programme) for the use of the diffractometer at the School of Chemistry, Bharathidasan University, Tiruchirappalli, Tamilnadu, India.

references
References top

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