Hexaaqua­manganese(II) dipicrate dihydrate

In the title compound, [Mn(H₂O)₆](C₆H₂N₃O₇)₂·2H₂O, the manganese cation, on an inversion centre, is coordinated by six water mol­ecules, but the picrate anion has no coordinative inter­action with the manganese cation. The anions in the stack are linked via short inter­molecular O...C (3.013 and 2.973 Å) and C...C (3.089 and 3.065 Å) contacts and hydrogen bonds.

Key indicators

• Single-crystal X-ray study
• T = 294 K
• Mean [sigma](C-C) = 0.005 Å
• R factor = 0.047
• wR factor = 0.158
• Data-to-parameter ratio = 10.1

checkCIF/PLATON results

No syntax errors found



Alert level B
PLAT432_ALERT_2_B Short Inter X...Y Contact  C2     ..  C2      ..       3.09 Ang.
PLAT432_ALERT_2_B Short Inter X...Y Contact  C4     ..  C4      ..       3.06 Ang.

Alert level C
PLAT152_ALERT_1_C Supplied and Calc Volume s.u. Inconsistent .....          ?
PLAT432_ALERT_2_C Short Inter X...Y Contact  O6     ..  C1      ..       3.01 Ang.
PLAT432_ALERT_2_C Short Inter X...Y Contact  O7     ..  C5      ..       2.97 Ang.
PLAT731_ALERT_1_C Bond    Calc     0.84(4), Rep   0.846(10) ......       4.00 su-Ra
              O1   -H1A     1.555   1.555
PLAT731_ALERT_1_C Bond    Calc     0.85(4), Rep   0.852(10) ......       4.00 su-Ra
              O1   -H1B     1.555   1.555
PLAT731_ALERT_1_C Bond    Calc     0.85(3), Rep   0.848(10) ......       3.00 su-Ra
              O2   -H2A     1.555   1.555
PLAT731_ALERT_1_C Bond    Calc     0.84(3), Rep   0.841(10) ......       3.00 su-Ra
              O2   -H2B     1.555   1.555
PLAT731_ALERT_1_C Bond    Calc     0.83(3), Rep   0.832(10) ......       3.00 su-Ra
              O3   -H3A     1.555   1.555
PLAT731_ALERT_1_C Bond    Calc     0.85(3), Rep   0.847(10) ......       3.00 su-Ra
              O11  -H11A    1.555   1.555
PLAT735_ALERT_1_C D-H     Calc     0.84(4), Rep   0.846(10) ......       4.00 su-Ra
              O1   -H1A     1.555   1.555
PLAT735_ALERT_1_C D-H     Calc     0.85(4), Rep   0.852(10) ......       4.00 su-Ra
              O1   -H1B     1.555   1.555
PLAT735_ALERT_1_C D-H     Calc     0.85(3), Rep   0.848(10) ......       3.00 su-Ra
              O2   -H2A     1.555   1.555
PLAT735_ALERT_1_C D-H     Calc     0.85(3), Rep   0.848(10) ......       3.00 su-Ra
              O2   -H2A     1.555   1.555
PLAT735_ALERT_1_C D-H     Calc     0.83(3), Rep   0.832(10) ......       3.00 su-Ra
              O3   -H3A     1.555   1.555
PLAT735_ALERT_1_C D-H     Calc     0.85(3), Rep   0.847(10) ......       3.00 su-Ra
              O11  -H11A    1.555   1.555
PLAT735_ALERT_1_C D-H     Calc     0.84(3), Rep   0.841(10) ......       3.00 su-Ra
              O2   -H2B     1.555   1.555
PLAT736_ALERT_1_C H...A   Calc     1.94(4), Rep   1.938(12) ......       3.33 su-Ra
              H1A  -O11     1.555   7.575
PLAT736_ALERT_1_C H...A   Calc     2.05(3), Rep   2.048(12) ......       2.50 su-Ra
              H2A  -O10     1.555   3.645
PLAT736_ALERT_1_C H...A   Calc     1.95(3), Rep   1.951(12) ......       2.50 su-Ra
              H3A  -O11     1.555   1.545

Alert level G
PLAT860_ALERT_3_G Note: Number of Least-Squares Restraints .......          8

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

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

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S1. Comment

Picrate is commonly used as an accompanying ion in many systems involving extraction and transport of metal ions to improve the extractability and selectivity (Zhang et al., 2003; Bibal et al., 2003; García et al., 2004). In many structures, picrate interacts as monodentate, bidentate and tridentate ligand (Olsher et al., 1996). Besides, picrate is a penta-dentate ligand when it coordinates with sodium or potassium cation by chelating pairs of oxygen atoms from p-nitro groups of adjacent picrates, and with successive cation linking the array into two or three-dimensional network (Harrowfield et al., 1995a; Maartmann-Moe, 1969). Furthermore, the picrate interacts as a heptadentate ligand through all its available oxygen donor atoms to coordinate with caesium (Harrowfield et al., 1995a).

Fig. 1 shows the structure and the atomic numbering schemes of the crystal structure of the title manganese picrate complex (I). This situation is similar to the crystal structure of iron (II) picrate (Honda et al., 2003) and Magnesium (II) picrate (Harrowfield et al., 1995b) and the picrate anion adopts a keto form with C6—O10 bond distance of 1.257 (4) Å, C1—C6 and C5—C6 bond distance of 1.447 (5) and 1.456 (5) Å, respectively, which is longer than the other C—C bond lengths (between 1.374 (5) to 1.460 (4) Å) in the benzene ring. The Mn—O distance ranges from 2.120 (2) to 2.190 (2) Å. The bond angle C1—C6—C5 is 111.9 (3)°, which is the case in some picrate complexes, while the corresponding bond angle of picric acid is 116.4 (5)° (Yang et al., 2001). Selected bond lengths and angles are given in Table 1.

In the case of planarity of picrate anion, the ortho nitro group are twisted relative to the plane of the benzene ring, (between 19.01 and 27.69°), while para-positioned nitro group is deviated 13.02° off the benzene ring. The picrate ions are stacked head-to-tail, presumably as a result of charge-transfer interactions. The anion in the stack are linked via short intermolecular O···C and C···C contacts of 3.013, 2.973, 3.089 and 3.065Å for O6···C1^x, O7···C5^xi, C2···C2^x and C4···C4^xi [symmetry codes: (x) 1/2 - x, 3/2 - y, z; (xi) 1/2 - x, 5/2 - y, z] respectively (Fig.2). The picrate anions are not parallel to one another, and the dihedral angles between neighbouring benzene planes are 25.01°, 25.25° and 3.48° respectively.

Related literature

For related literature, see: Bibal et al. (2003); García et al. (2004); Harrowfield et al. (1995a,b); Honda et al. (2003); Ji & Chen (1996); Maartmann-Moe (1969); Olsher et al. (1996); Yang et al. (2001); Zhang et al. (2003).

S2. Experimental

The title compound (I) was obtained by the reaction of 3.20 g (13.96 mmol) picric acid with 0.80 g (6.98 mmol) manganese carbonate in water (350 ml), according to Ji et al., 1996. Heating has been continued for another 1 h and filtered while it was still hot. The filtrate was partially evaporated and left to stand in open atmosphere for a few days, during which time, yellow crystals suitable for X-Ray determination were obtained. Analysis, calculated for C₁₂H₂₀N₆O₂₂Mn: C 21.98, H 3.05, N 12.80, Mn 8.40%; Found: C 22.35, H 3.34, N 12.46, Mn 8.68%.

S3. Refinement

All H atoms of water were located from difference map and then refined with O—H distances restrained to 0.85 (1) Å. All other H atoms were positioned geometrically and refined using a riding mode with the C—H bond lengths of 0.93 Å and U_iso(H)=1.2U_eq(carrier atom).

Computing details

Data collection: SMART (Bruker, 1997); cell refinement: SAINT (Bruker, 1997); data reduction: SAINT (Bruker, 1997); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL (Bruker, 1997); software used to prepare material for publication: SHELXTL (Bruker, 1997).

Figures

	Fig. 1. The molecular structure of (I), with displacement ellipsoids at the 50% probability level and the atomic labeling scheme.
	Fig. 2. The crystal structure of (I), projected along the c axis. The dashed lines indicate short intermolecular contacts with N···O, C···C and O···C distances less than 3.0, 3.2 and 3.0 Å, respectively. [Symmetry mode: (x) 1/2 - x, 3/2 - y, z; (xi) 1/2 - x, 5/2 - y, z]

Hexaaquamanganese(II) dipicrate dihydrate

Crystal data

[Mn(H2O)6](C6H2N3O7)2·2H2O	F(000) = 1340
Mr = 655.28	Dx = 1.814 Mg m^−3
Orthorhombic, Pccn	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ab 2ac	Cell parameters from 3819 reflections
a = 25.344 (6) Å	θ = 3.0–26.9°
b = 7.1625 (17) Å	µ = 0.67 mm^−1
c = 13.217 (3) Å	T = 294 K
V = 2399.2 (9) Å^3	Prism, yellow
Z = 4	0.28 × 0.24 × 0.20 mm

Data collection

Bruker SMART CCD area-detector diffractometer	2122 independent reflections
Radiation source: fine-focus sealed tube	1643 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.033
ϕ and ω scans	θmax = 25.0°, θmin = 3.0°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −30→20
Tmin = 0.835, Tmax = 0.878	k = −6→8
11295 measured reflections	l = −14→15

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)] = 0.047	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.158	H atoms treated by a mixture of independent and constrained refinement
S = 1.11	w = 1/[σ^2(Fo^2) + (0.1031P)^2 + 1.8926P] where P = (Fo^2 + 2Fc^2)/3
2122 reflections	(Δ/σ)max = 0.002
211 parameters	Δρmax = 0.50 e Å^−3
8 restraints	Δρmin = −1.20 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.

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

	x	y	z	Uiso*/Ueq
Mn1	0.5000	0.0000	0.5000	0.0324 (3)
O1	0.46126 (10)	0.2424 (4)	0.4457 (2)	0.0421 (7)
H1A	0.4744 (16)	0.322 (5)	0.406 (3)	0.051*
H1B	0.4352 (12)	0.300 (6)	0.472 (3)	0.051*
O2	0.55826 (9)	0.1880 (4)	0.56780 (19)	0.0330 (6)
H2A	0.5744 (14)	0.275 (4)	0.537 (3)	0.040*
H2B	0.5784 (12)	0.128 (5)	0.606 (2)	0.040*
O3	0.45862 (10)	0.0148 (5)	0.6406 (2)	0.0445 (8)
H3A	0.4722 (18)	0.009 (6)	0.6979 (17)	0.053*
H3B	0.4257 (5)	0.002 (6)	0.637 (4)	0.053*
O4	0.38727 (10)	0.9511 (5)	0.2517 (2)	0.0513 (8)
O5	0.31431 (10)	0.8379 (4)	0.30495 (17)	0.0370 (6)
O6	0.15343 (9)	0.9452 (4)	0.1363 (2)	0.0377 (7)
O7	0.15241 (9)	1.0752 (4)	−0.0108 (2)	0.0394 (7)
O8	0.31310 (10)	1.1774 (4)	−0.18909 (18)	0.0380 (6)
O9	0.38129 (10)	1.0114 (4)	−0.15080 (19)	0.0366 (7)
O10	0.39594 (9)	0.9860 (4)	0.05051 (18)	0.0341 (6)
N1	0.34078 (10)	0.9135 (4)	0.2395 (2)	0.0283 (7)
N2	0.17602 (11)	1.0079 (4)	0.0613 (2)	0.0251 (7)
N3	0.33772 (10)	1.0754 (4)	−0.1311 (2)	0.0258 (6)
C1	0.31536 (13)	0.9605 (5)	0.1440 (2)	0.0242 (7)
C2	0.26072 (13)	0.9623 (5)	0.1463 (3)	0.0251 (7)
H2	0.2428	0.9370	0.2062	0.030*
C3	0.23318 (13)	1.0019 (4)	0.0588 (2)	0.0235 (7)
C4	0.25917 (13)	1.0386 (4)	−0.0315 (3)	0.0245 (7)
H4	0.2402	1.0684	−0.0895	0.029*
C5	0.31330 (13)	1.0304 (4)	−0.0340 (2)	0.0229 (7)
C6	0.34639 (13)	0.9917 (4)	0.0536 (3)	0.0246 (7)
O11	0.50741 (10)	0.9801 (4)	0.8282 (2)	0.0377 (7)
H11A	0.4971 (15)	0.878 (3)	0.854 (3)	0.045*
H11B	0.5400 (6)	0.982 (6)	0.842 (3)	0.045*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Mn1	0.0302 (5)	0.0345 (5)	0.0324 (5)	−0.0018 (3)	−0.0020 (3)	0.0010 (3)
O1	0.0328 (14)	0.0450 (17)	0.0486 (17)	0.0143 (12)	0.0079 (12)	0.0177 (13)
O2	0.0237 (12)	0.0355 (14)	0.0398 (15)	−0.0053 (10)	−0.0081 (10)	0.0038 (11)
O3	0.0233 (14)	0.080 (2)	0.0299 (15)	−0.0049 (13)	0.0010 (11)	0.0035 (14)
O4	0.0246 (14)	0.098 (2)	0.0312 (15)	−0.0061 (14)	−0.0079 (11)	0.0097 (15)
O5	0.0351 (13)	0.0514 (17)	0.0247 (13)	0.0044 (12)	0.0019 (10)	0.0052 (12)
O6	0.0214 (13)	0.0518 (17)	0.0399 (15)	0.0010 (11)	0.0062 (11)	0.0082 (13)
O7	0.0202 (13)	0.0538 (18)	0.0443 (16)	0.0023 (12)	−0.0087 (11)	0.0137 (13)
O8	0.0415 (14)	0.0462 (16)	0.0263 (13)	0.0089 (12)	−0.0015 (11)	0.0059 (12)
O9	0.0194 (13)	0.0578 (18)	0.0325 (14)	0.0028 (11)	0.0030 (10)	−0.0004 (12)
O10	0.0160 (12)	0.0588 (18)	0.0274 (14)	0.0035 (10)	−0.0005 (9)	0.0030 (11)
N1	0.0224 (15)	0.0361 (17)	0.0265 (15)	0.0045 (12)	−0.0018 (12)	−0.0022 (13)
N2	0.0187 (14)	0.0231 (15)	0.0334 (17)	−0.0001 (11)	−0.0012 (12)	−0.0012 (12)
N3	0.0235 (14)	0.0308 (15)	0.0231 (14)	−0.0023 (12)	−0.0018 (11)	−0.0031 (12)
C1	0.0208 (16)	0.0291 (18)	0.0226 (16)	0.0028 (13)	−0.0026 (13)	−0.0010 (14)
C2	0.0218 (17)	0.0265 (18)	0.0269 (17)	0.0002 (13)	0.0015 (13)	−0.0006 (14)
C3	0.0180 (16)	0.0232 (16)	0.0294 (18)	0.0012 (12)	−0.0011 (13)	−0.0019 (13)
C4	0.0204 (17)	0.0259 (17)	0.0271 (17)	0.0018 (13)	−0.0060 (13)	−0.0009 (14)
C5	0.0200 (16)	0.0263 (18)	0.0224 (16)	−0.0011 (13)	0.0000 (13)	−0.0007 (13)
C6	0.0208 (17)	0.0265 (18)	0.0265 (19)	0.0016 (13)	−0.0029 (13)	−0.0023 (13)
O11	0.0303 (15)	0.0455 (17)	0.0374 (16)	−0.0029 (12)	−0.0032 (12)	0.0069 (12)

Geometric parameters (Å, º)

Mn1—O1	2.120 (3)	C1—C2	1.385 (5)
Mn1—O1^i	2.120 (3)	C1—C6	1.447 (5)
Mn1—O3	2.136 (3)	C2—C3	1.380 (5)
Mn1—O3^i	2.136 (3)	C3—C4	1.389 (5)
Mn1—O2	2.190 (2)	C4—C5	1.374 (5)
Mn1—O2	2.190 (2)	C5—C6	1.456 (5)
O4—N1	1.219 (4)	C2—H2	0.931
O5—N1	1.222 (4)	C4—H4	0.931
O6—N2	1.229 (4)	O1—H1A	0.846 (10)
O7—N2	1.225 (4)	O1—H1B	0.852 (10)
O8—N3	1.229 (4)	O2—H2A	0.848 (10)
O9—N3	1.224 (4)	O2—H2B	0.841 (10)
O10—C6	1.257 (4)	O3—H3A	0.832 (10)
N1—C1	1.456 (4)	O3—H3B	0.841 (10)
N2—C3	1.450 (4)	O11—H11A	0.847 (10)
N3—C5	1.460 (4)	O11—H11B	0.846 (10)
O1—Mn1—O1^i	180.0	O9—N3—O8	123.2 (3)
O1—Mn1—O3	91.52 (11)	O9—N3—C5	119.1 (3)
O1^i—Mn1—O3	88.48 (11)	O8—N3—C5	117.7 (3)
O1—Mn1—O3^i	88.48 (11)	C2—C1—C6	124.1 (3)
O1^i—Mn1—O3^i	91.52 (11)	C2—C1—N1	115.1 (3)
O3—Mn1—O3^i	180.0	C6—C1—N1	120.7 (3)
O1—Mn1—O2^i	93.02 (11)	C3—C2—C1	119.3 (3)
O1^i—Mn1—O2^i	86.98 (11)	C2—C3—C4	121.3 (3)
O3—Mn1—O2^i	93.18 (11)	C2—C3—N2	119.5 (3)
O3^i—Mn1—O2^i	86.83 (11)	C4—C3—N2	119.2 (3)
O1—Mn1—O2	86.98 (11)	C5—C4—C3	119.1 (3)
O1^i—Mn1—O2	93.02 (11)	C4—C5—C6	124.4 (3)
O3—Mn1—O2	86.83 (11)	C4—C5—N3	115.8 (3)
O3^i—Mn1—O2	93.17 (11)	C6—C5—N3	119.8 (3)
O2^i—Mn1—O2	180.0	O10—C6—C1	124.4 (3)
O4—N1—O5	122.3 (3)	O10—C6—C5	123.8 (3)
O4—N1—C1	119.5 (3)	C1—C6—C5	111.9 (3)
O5—N1—C1	118.3 (3)	C3—C2—H2	120.36
O7—N2—O6	123.0 (3)	C1—C2—H2	120.37
O7—N2—C3	118.8 (3)	C3—C4—H4	120.43
O6—N2—C3	118.2 (3)	C5—C4—H4	120.41
O4—N1—C1—C2	−162.6 (3)	C3—C4—C5—C6	−2.3 (5)
O5—N1—C1—C2	17.1 (4)	C3—C4—C5—N3	−178.5 (3)
O4—N1—C1—C6	20.8 (5)	O9—N3—C5—C4	−154.6 (3)
O5—N1—C1—C6	−159.6 (3)	O8—N3—C5—C4	25.5 (4)
C6—C1—C2—C3	−2.2 (5)	O9—N3—C5—C6	29.0 (4)
N1—C1—C2—C3	−178.8 (3)	O8—N3—C5—C6	−150.8 (3)
C1—C2—C3—C4	0.5 (5)	C2—C1—C6—O10	−178.3 (3)
C1—C2—C3—N2	−178.7 (3)	N1—C1—C6—O10	−1.9 (5)
O7—N2—C3—C2	167.0 (3)	C2—C1—C6—C5	1.6 (5)
O6—N2—C3—C2	−12.8 (4)	N1—C1—C6—C5	178.0 (3)
O7—N2—C3—C4	−12.2 (4)	C4—C5—C6—O10	−179.4 (3)
O6—N2—C3—C4	168.0 (3)	N3—C5—C6—O10	−3.4 (5)
C2—C3—C4—C5	1.7 (5)	C4—C5—C6—C1	0.7 (4)
N2—C3—C4—C5	−179.1 (3)	N3—C5—C6—C1	176.7 (3)

Symmetry code: (i) −x+1, −y, −z+1.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1A···O11^ii	0.85 (1)	1.94 (1)	2.780 (4)	173 (4)
O1—H1B···O10^iii	0.85 (1)	2.10 (2)	2.906 (4)	157 (4)
O2—H2A···O10^iv	0.85 (1)	2.05 (1)	2.889 (4)	172 (4)
O2—H2A···O9^iv	0.85 (1)	2.53 (4)	2.986 (4)	115 (3)
O3—H3A···O11^v	0.83 (1)	1.95 (1)	2.782 (4)	176 (5)
O3—H3B···O6^vi	0.84 (1)	2.05 (1)	2.884 (4)	174 (5)
O11—H11A···O2^vii	0.85 (1)	2.21 (2)	3.006 (4)	156 (4)
O11—H11B···O10^viii	0.85 (1)	2.17 (2)	2.938 (4)	151 (4)
O11—H11B···O4^viii	0.85 (1)	2.27 (3)	2.913 (4)	133 (4)
O2—H2B···O4^ix	0.84 (1)	2.14 (2)	2.930 (4)	156 (4)

Symmetry codes: (ii) x, −y+3/2, z−1/2; (iii) x, −y+3/2, z+1/2; (iv) −x+1, y−1/2, −z+1/2; (v) x, y−1, z; (vi) −x+1/2, y−1, z+1/2; (vii) −x+1, y+1/2, −z+3/2; (viii) −x+1, −y+2, −z+1; (ix) −x+1, −y+1, −z+1.