Retracted: catena-Poly[[aqua­(pyrazine-2-carboxyl­ato-κ²N¹,O)manganese(II)]-μ-pyrazine-2-carboxyl­ato-κ³N¹,O:N⁴]

The title compound, [Mn(C₅H₃N₂O₂)₂(H₂O)]_n, prepared by hydro­thermal synthesis, is isostructural with its Fe^II, Co^II, Ni^II and Cu^II analogues. The asymmetric unit contains two bidendate pyrazine-2-carboxyl­ate anions coordinated to Mn^II in the equatorial plane through one N and one O atom. The Mn^II atoms are linked into chains by the second N atom of one of the pyrazine-2-carboxyl­ate anions coordinating to an axial site of a neighbouring Mn^II atom. The slightly distorted octa­hedral coordination around Mn^II is completed by a water mol­ecule, which forms hydrogen bonds to link the chains into a three-dimensional structure. The investigated crystal was an inversion twin.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.006 Å
• R factor = 0.039
• wR factor = 0.101
• Data-to-parameter ratio = 14.2

checkCIF/PLATON results

No syntax errors found



Alert level C
STRVA01_ALERT_4_C           Flack test results are ambiguous.
           From the CIF: _refine_ls_abs_structure_Flack    0.480
           From the CIF: _refine_ls_abs_structure_Flack_su    0.030
PLAT029_ALERT_3_C _diffrn_measured_fraction_theta_full Low .......       0.98
PLAT033_ALERT_2_C Flack Parameter Value Deviates 2 * su from zero.       0.48
PLAT094_ALERT_2_C Ratio of Maximum / Minimum Residual Density ....       3.06
PLAT142_ALERT_4_C su on b - Axis Small or Missing (x 100000) .....         10 Ang.
PLAT143_ALERT_4_C su on c - Axis Small or Missing (x 100000) .....         10 Ang.
PLAT180_ALERT_3_C Check Cell Rounding: # of Values Ending with 0 =          3
PLAT242_ALERT_2_C Check Low       Ueq as Compared to Neighbors for        Mn1
PLAT736_ALERT_1_C H...A   Calc     1.86(4), Rep   1.862(12) ......       3.33 su-Ra
              H2W  -O2      1.555   4.555

Alert level G
REFLT03_ALERT_4_G Please check that the estimate of the number of Friedel pairs is
            correct. If it is not, please give the correct count in the
            _publ_section_exptl_refinement section of the submitted CIF.
           From the CIF: _diffrn_reflns_theta_max           27.99
           From the CIF: _reflns_number_total               2661
           Count of symmetry unique reflns         1614
           Completeness (_total/calc)            164.87%
           TEST3: Check Friedels for noncentro structure
           Estimate of Friedel pairs measured      1047
           Fraction of Friedel pairs measured     0.649
           Are heavy atom types Z>Si present        yes
PLAT199_ALERT_1_G Check the Reported _cell_measurement_temperature        293 K
PLAT200_ALERT_1_G Check the Reported _diffrn_ambient_temperature .        293 K
PLAT794_ALERT_5_G Check Predicted Bond Valency for Mn1         (3)       2.86
PLAT860_ALERT_3_G Note: Number of Least-Squares Restraints .......          3

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

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

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S1. Comment

The title compound, [Mn(C₅H₃N₂O₂)₂(H₂O)]_n, is isostructural with its Fe^II, Co^II, Ni^II, and Cu^II analogues (Hao & Liu, (2007); Hao, Mu & Liu, (2007); Gao et al. (2007a); Gao et al. (2007b)).

The Mn^II atom is coordinated in a bidentate fashion by two O and two N atoms from two independent pyrazine-2-carboxylate anions. The distorted octahedral coordiantion is completed by another N atom from a third pyrazine-2-carboxylate ligand, and by the O atom of a water molecule (Figure 1). The Mn—N and Mn—O bond lengths are in the range of 2.094 (3)–2.137 (3) and 2.010 (3)–2.072 (3) Å, respectively.

One pyrazine-2-carboxylate ligand coordinates to a neighbouring Mn^II atom via its second N atom, leading to a polymeric structure with zigzag chains extending parallel to the b axis (Figure 2). Hydrogen bonding between the water molecules stablizes the structure. The refined Flack parameter of 0.48 (3) indicates that the crystal is an inversion twin.

Related literature

For the isostructural Fe^II, Co^II, Ni^II and Cu^II analogues, see: Hao & Liu (2007); Hao, Mu & Liu (2007); Gao et al. (2007a,b).

S2. Experimental

All chemicals were used as purchased from Jinan Henghua Sci & Tec Co. Ltd. A mixture of Mn(CH₃CO₂)₂ (0.5 mmol), KOH (0.5 mmol), 2-pyrazine carboxylic acid (0.5 mmol), EtOH (8 ml) and H₂O (8 ml) in a 25 ml Teflon-lined stainless steel autoclave was kept at 413 K for 2 d. On cooling to room temperature, colourless crystals were obtained in a yield of 36%. Elemental analysis calculated: C 37.62, H 2.51, N 17.55%; found: C 37.56, H 2.47, N 17.51%.

S3. Refinement

H atoms on C atoms were placed geometrically and refined as riding atoms with C—H = 0.93Å and U_iso(H) = 1.2U_eq(C). The H atoms of the water molecule were located from difference Fourier maps and were refined with distance restraints of O—H = 0.82 (1) Å and H···H = 1.38 (2) Å, and with U_iso(H) = 0.08 Ų. The refined Flack parameter (Flack, 1983) from 1086 Friedel pairs is 0.48 (3), indicating that the crystal is an inversion twin.

Computing details

Data collection: APEX2 (Bruker, 2005); cell refinement: SAINT-Plus (Bruker, 2001); data reduction: SAINT-Plus; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL (Bruker, 2001); software used to prepare material for publication: SHELXTL.

Figures

	Fig. 1. Asymmetric unit of the title compound expanded to show the complete coordination sphere of Mn^II. Displacement ellipsoids are shown at 30% probability for non-H atoms. Symmetry code (I): 1 - x, 1/2 + y, 1/2 - z.
	Fig. 2. View of the [Mn(C5H3N2O2)2(H2O)]n coordination polymer.

catena-Poly[[aqua(pyrazine-2-carboxylato-κ²N¹,O)manganese(II)]- µ-pyrazine-2-carboxylato-κ³-κ²N¹,O:N⁴]

Crystal data

[Mn(C5H3N2O2)2(H2O)]	F(000) = 644
Mr = 319.14	Dx = 1.844 Mg m^−3
Orthorhombic, P212121	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2ab	Cell parameters from 2661 reflections
a = 7.722 (1) Å	θ = 2.5–28.0°
b = 10.0002 (1) Å	µ = 1.18 mm^−1
c = 14.8836 (1) Å	T = 293 K
V = 1149.33 (15) Å^3	Cube, colourless
Z = 4	0.10 × 0.10 × 0.10 mm

Data collection

Bruker APEX II CCD diffractometer	2661 independent reflections
Radiation source: fine-focus sealed tube	2367 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.032
φ and ω scans	θmax = 28.0°, θmin = 2.5°
Absorption correction: multi-scan (SADABS; Bruker, 2001)	h = −9→10
Tmin = 0.891, Tmax = 0.891	k = −12→13
7188 measured reflections	l = −15→19

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F^2 > 2σ(F^2)] = 0.039	H atoms treated by a mixture of independent and constrained refinement
wR(F^2) = 0.101	w = 1/[σ^2(Fo^2) + (0.059P)^2 + 0.7652P] where P = (Fo^2 + 2Fc^2)/3
S = 1.00	(Δ/σ)max < 0.001
2661 reflections	Δρmax = 1.03 e Å^−3
187 parameters	Δρmin = −0.34 e Å^−3
3 restraints	Absolute structure: Flack (1983), 1086 Friedel pairs
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: 0.48 (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
C1	−0.1432 (6)	0.5282 (4)	−0.0196 (3)	0.0336 (9)
C2	0.0370 (5)	0.5738 (4)	−0.0409 (3)	0.0328 (9)
C3	0.0750 (6)	0.6650 (4)	−0.1082 (3)	0.0431 (10)
H3	−0.0160	0.7017	−0.1408	0.052*
C4	0.3581 (6)	0.6483 (4)	−0.0792 (3)	0.0432 (10)
H4	0.4724	0.6719	−0.0908	0.052*
C5	0.3240 (6)	0.5575 (4)	−0.0107 (3)	0.0366 (9)
H5	0.4153	0.5233	0.0229	0.044*
C6	0.3050 (5)	0.1913 (4)	0.1834 (3)	0.0277 (8)
C7	0.1282 (5)	0.1459 (4)	0.2115 (2)	0.0270 (7)
C8	−0.1645 (5)	0.1694 (4)	0.2000 (3)	0.0353 (10)
H8	−0.2615	0.2098	0.1749	0.042*
C10	−0.1851 (5)	0.0674 (4)	0.2636 (3)	0.0327 (9)
H10	−0.2964	0.0421	0.2805	0.039*
C11	0.1061 (5)	0.0419 (4)	0.2732 (3)	0.0307 (9)
H11	0.2031	−0.0024	0.2953	0.037*
H1W	0.006 (5)	0.240 (6)	−0.056 (3)	0.080*
H2W	0.156 (5)	0.178 (5)	−0.028 (4)	0.080*
Mn1	0.07321 (6)	0.36583 (5)	0.09074 (3)	0.01617 (13)
N1	−0.0492 (4)	0.0050 (3)	0.3010 (2)	0.0293 (7)
N2	−0.0065 (4)	0.2087 (3)	0.1753 (2)	0.0303 (7)
N3	0.1645 (4)	0.5190 (3)	0.0073 (2)	0.0299 (7)
N4	0.2341 (5)	0.7020 (4)	−0.1282 (3)	0.0505 (10)
O1	0.0814 (5)	0.2346 (3)	−0.01690 (19)	0.0399 (7)
O2	−0.1538 (4)	0.4351 (3)	0.04084 (19)	0.0333 (6)
O3	−0.2617 (4)	0.5807 (4)	−0.0589 (3)	0.0567 (9)
O4	0.3053 (3)	0.2971 (3)	0.13085 (18)	0.0315 (6)
O5	0.4313 (4)	0.1305 (3)	0.20942 (19)	0.0415 (6)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
C1	0.029 (2)	0.036 (2)	0.036 (2)	−0.0012 (17)	−0.0035 (17)	0.0013 (17)
C2	0.035 (2)	0.033 (2)	0.030 (2)	0.0042 (17)	−0.0003 (16)	−0.0001 (16)
C3	0.033 (2)	0.048 (2)	0.049 (3)	0.002 (2)	−0.005 (2)	0.0146 (18)
C4	0.035 (2)	0.044 (2)	0.051 (3)	−0.002 (2)	0.005 (2)	0.009 (2)
C5	0.032 (2)	0.037 (2)	0.041 (2)	0.0014 (18)	−0.0017 (18)	0.0019 (17)
C6	0.0222 (18)	0.0309 (18)	0.0300 (19)	−0.0004 (15)	−0.0003 (14)	−0.0031 (15)
C7	0.0266 (17)	0.0282 (18)	0.0262 (17)	0.0032 (15)	0.0021 (13)	−0.0009 (16)
C8	0.0233 (19)	0.042 (3)	0.040 (2)	−0.0008 (18)	−0.0011 (17)	0.0003 (18)
C10	0.027 (2)	0.033 (2)	0.038 (2)	−0.0034 (17)	0.0000 (16)	0.0052 (17)
C11	0.027 (2)	0.0339 (19)	0.0308 (19)	0.0019 (16)	0.0003 (16)	0.0025 (16)
Mn1	0.0136 (2)	0.0179 (2)	0.0170 (2)	−0.00008 (19)	0.00074 (19)	0.00062 (19)
N1	0.0295 (17)	0.0290 (15)	0.0293 (15)	−0.0008 (14)	−0.0005 (14)	0.0049 (13)
N2	0.0247 (15)	0.0327 (17)	0.0334 (18)	−0.0010 (14)	0.0014 (14)	−0.0021 (14)
N3	0.0293 (17)	0.0296 (17)	0.0307 (17)	−0.0006 (14)	−0.0006 (14)	0.0019 (13)
N4	0.042 (2)	0.055 (2)	0.055 (2)	−0.007 (2)	0.0056 (19)	0.019 (2)
O1	0.0371 (16)	0.0445 (16)	0.0383 (15)	0.0116 (16)	−0.0078 (14)	−0.0132 (13)
O2	0.0231 (13)	0.0360 (15)	0.0407 (16)	−0.0022 (12)	0.0007 (12)	−0.0003 (13)
O3	0.0314 (17)	0.076 (2)	0.063 (2)	0.0063 (17)	−0.0064 (15)	0.0208 (19)
O4	0.0267 (14)	0.0359 (15)	0.0321 (14)	−0.0014 (12)	0.0022 (11)	0.0018 (12)
O5	0.0258 (13)	0.0494 (16)	0.0492 (16)	0.0051 (17)	−0.0006 (13)	0.0100 (14)

Geometric parameters (Å, º)

C1—O3	1.206 (5)	C8—N2	1.334 (5)
C1—O2	1.297 (5)	C8—C10	1.401 (6)
C1—C2	1.498 (6)	C8—H8	0.930
C2—N3	1.335 (5)	C10—N1	1.341 (5)
C2—C3	1.387 (6)	C10—H10	0.930
C3—N4	1.317 (6)	C11—N1	1.321 (5)
C3—H3	0.930	C11—H11	0.930
C4—N4	1.318 (6)	Mn1—O4	2.010 (3)
C4—C5	1.390 (6)	Mn1—O2	2.026 (3)
C4—H4	0.930	Mn1—O1	2.072 (3)
C5—N3	1.318 (5)	Mn1—N3	2.094 (3)
C5—H5	0.930	Mn1—N2	2.106 (3)
C6—O5	1.213 (5)	Mn1—N1^i	2.137 (3)
C6—O4	1.315 (5)	N1—Mn1^ii	2.137 (3)
C6—C7	1.498 (5)	O1—H1W	0.83 (4)
C7—N2	1.329 (5)	O1—H2W	0.82 (4)
C7—C11	1.399 (5)
O3—C1—O2	126.9 (4)	O4—Mn1—O2	175.74 (12)
O3—C1—C2	118.0 (4)	O4—Mn1—O1	89.19 (12)
O2—C1—C2	115.1 (3)	O2—Mn1—O1	87.68 (12)
N3—C2—C3	120.1 (4)	O4—Mn1—N3	97.25 (12)
N3—C2—C1	116.5 (3)	O2—Mn1—N3	79.85 (12)
C3—C2—C1	123.3 (4)	O1—Mn1—N3	89.68 (13)
N4—C3—C2	123.0 (4)	O4—Mn1—N2	80.08 (12)
N4—C3—H3	118.5	O2—Mn1—N2	102.79 (12)
C2—C3—H3	118.5	O1—Mn1—N2	89.91 (13)
N4—C4—C5	122.3 (4)	N3—Mn1—N2	177.31 (14)
N4—C4—H4	118.9	O4—Mn1—N1^i	94.36 (12)
C5—C4—H4	118.9	O2—Mn1—N1^i	88.78 (12)
N3—C5—C4	121.1 (4)	O1—Mn1—N1^i	176.45 (14)
N3—C5—H5	119.4	N3—Mn1—N1^i	90.00 (13)
C4—C5—H5	119.4	N2—Mn1—N1^i	90.57 (12)
O5—C6—O4	126.3 (4)	C11—N1—C10	116.8 (3)
O5—C6—C7	119.5 (3)	C11—N1—Mn1^ii	119.7 (3)
O4—C6—C7	114.3 (3)	C10—N1—Mn1^ii	123.2 (3)
N2—C7—C11	121.5 (3)	C7—N2—C8	117.7 (3)
N2—C7—C6	117.2 (3)	C7—N2—Mn1	111.4 (3)
C11—C7—C6	121.3 (3)	C8—N2—Mn1	130.7 (3)
N2—C8—C10	120.3 (4)	C5—N3—C2	117.4 (3)
N2—C8—H8	119.8	C5—N3—Mn1	130.5 (3)
C10—C8—H8	119.8	C2—N3—Mn1	111.7 (3)
N1—C10—C8	122.0 (4)	C3—N4—C4	116.0 (4)
N1—C10—H10	119.0	Mn1—O1—H1W	119 (3)
C8—C10—H10	119.0	Mn1—O1—H2W	128 (3)
N1—C11—C7	121.6 (3)	H1W—O1—H2W	113 (3)
N1—C11—H11	119.2	C1—O2—Mn1	116.4 (3)
C7—C11—H11	119.2	C6—O4—Mn1	116.7 (2)

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

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1W···O4^iii	0.83 (4)	1.94 (2)	2.742 (4)	162 (6)
O1—H2W···O2^iv	0.82 (4)	1.86 (1)	2.681 (4)	171 (5)

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