Diaqua­[5-(2-pyrid­yl)tetra­zolato-κ²N¹,N⁵]manganese(II)

The title compound, [Mn(C₆H₄N₅)₂(H₂O)₂], was synthesized by the hydro­thermal reaction of Mn(NO₃)₂ with picolino­nitrile in the presence of NaN₃. The Mn atom lies on an inversion centre. The distorted octa­hedral Mn environment contains two planar trans-related N,N′-chelating 5-(2-pyrid­yl)­tetra­zolate ligands in the equatorial plane and two axial water mol­ecules. O—H...N hydrogen bonds generate an infinite three-dimensional network.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.002 Å
• R factor = 0.028
• wR factor = 0.072
• Data-to-parameter ratio = 15.7

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT232_ALERT_2_C Hirshfeld Test Diff (M-X)  Mn1    -   N1      ..       7.75 su

Alert level G
PLAT199_ALERT_1_G Check the Reported _cell_measurement_temperature        293 K
PLAT200_ALERT_1_G Check the Reported _diffrn_ambient_temperature .        293 K

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

   2 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   1 ALERT type 2 Indicator that the structure model may be wrong or deficient
   0 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

The tetrazole functional group has found a wide range of applications in coordination chemistry as ligands, in medicinal chemistry as a metabolically stable surrogate for a carboxylic acid group, and in materials science as high density energy materials(Wang et al., 2005; Dunica et al., 1991; Wittenberger & Donner, 1993). We report here the crystal structure of the title compound, 5-(2-pyridyl)tetrazolate-Manganese(II) dihydrate.

The Mn atom lies on an inversion centre. The distorted octahedral Mn environment contains two planar trans-related N,N-chelating 5-(2-pyridyl)tetrazolate ligands in the equatorial plane and two water molecules ligands. The pyridine and tetrazole rings are nearly coplanar and are twisted from each other by a dihedral angle of only 4.02 (0.09) °(Fig.1). The bond distances and bond angles of the tetrazole rings are in the usual ranges (Wang et al., 2005; Arp et al., 2000).

The O atoms from water molecules are involved in intermolecular hydrogen bonds building up an infinite three-dimensional network(Table 1, Fig. 2).

Related literature

For the chemisty of tetrazole, see: Arp et al. (2000); Dunica et al. (1991); Wang et al. (2005); Wittenberger & Donner (1993).

S2. Experimental

A mixture of picolinonitrile (0.2 mmol), NaN₃ (0.4 mmol), Mn(NO₃)₂(0.15 mmol) ethanol (1 ml) and a few drops of water sealed in a glass tube was maintained at 120 °C. Yellow block crystals suitable for X-ray analysis were obtained after 3 days.

S3. Refinement

All H atoms attached to C atoms were fixed geometrically and treated as riding with C—H = 0.93 Å and U_iso(H) = 1.2U_eq(C). H atoms of water molecule were located in difference Fourier maps and included in the subsequent refinement using restraints (O-H= 0.85 (1)Å and H···H= 1.49 (2)Å) with U_iso(H) = 1.5U_eq(O). In the last stage of refinement they were treated as riding on the O atom.

Computing details

Data collection: CrystalClear (Rigaku, 2005); cell refinement: CrystalClear (Rigaku, 2005); data reduction: CrystalClear (Rigaku, 2005); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEPIII (Burnett & Johnson, 1996), ORTEP-32 (Farrugia, 1998) and SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures

	Fig. 1. Molecular view of the title compound with the atomic numbering scheme. Displacement ellipsoids are drawn at the 50% probability level. H atoms have been omitted for clarity. [Symmetry code : (i) 1-x, 1-y, 1-z]
	Fig. 2. The crystal packing of the title compound viewed along the a axis showing the three dimensionnal hydrogen bondings network (dashed line). Hydrogen atoms not involved in hydrogen bonding have been omitted for clarity.

Diaqua[5-(2-pyridyl)tetrazolato-κ²N¹,N⁵]manganese(II)

Crystal data

[Mn(C6H4N5)2(H2O)2]	F(000) = 390
Mr = 383.26	Dx = 1.671 Mg m^−3
Monoclinic, P21/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 2090 reflections
a = 6.185 (3) Å	θ = 3.8–27.5°
b = 12.110 (7) Å	µ = 0.90 mm^−1
c = 10.615 (5) Å	T = 293 K
β = 106.597 (12)°	Block, yellow
V = 761.9 (7) Å^3	0.5 × 0.5 × 0.4 mm
Z = 2

Data collection

Rigaku Mercury2 (2x2 bin mode) diffractometer	1803 independent reflections
Radiation source: fine-focus sealed tube	1660 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.021
Detector resolution: 13.6612 pixels mm^-1	θmax = 27.9°, θmin = 2.6°
ω scans	h = −8→8
Absorption correction: multi-scan (CrystalClear; Rigaku, 2005)	k = −15→15
Tmin = 0.638, Tmax = 0.695	l = −13→13
7656 measured reflections

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)] = 0.028	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.071	H-atom parameters constrained
S = 1.11	w = 1/[σ^2(Fo^2) + (0.0346P)^2 + 0.2477P] where P = (Fo^2 + 2Fc^2)/3
1803 reflections	(Δ/σ)max = 0.001
115 parameters	Δρmax = 0.26 e Å^−3
0 restraints	Δρmin = −0.30 e Å^−3

Special details

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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	0.2334 (2)	0.69220 (11)	0.35475 (13)	0.0241 (3)
C2	0.4533 (2)	0.74376 (11)	0.41494 (13)	0.0244 (3)
C3	0.4930 (3)	0.85522 (12)	0.40133 (15)	0.0344 (3)
H3	0.3799	0.9008	0.3511	0.041*
C4	0.7043 (3)	0.89713 (13)	0.46408 (17)	0.0412 (4)
H4	0.7349	0.9717	0.4569	0.049*
C5	0.8696 (3)	0.82755 (14)	0.53750 (16)	0.0393 (4)
H5	1.0121	0.8544	0.5814	0.047*
C6	0.8179 (2)	0.71703 (13)	0.54410 (15)	0.0325 (3)
H6	0.9299	0.6698	0.5921	0.039*
Mn1	0.5000	0.5000	0.5000	0.02576 (11)
N1	0.61452 (19)	0.67490 (9)	0.48475 (11)	0.0255 (2)
N2	0.19348 (18)	0.58625 (9)	0.37478 (12)	0.0275 (2)
N3	−0.0219 (2)	0.56898 (11)	0.30475 (13)	0.0338 (3)
N4	−0.1061 (2)	0.66105 (11)	0.24559 (13)	0.0368 (3)
N5	0.0515 (2)	0.74084 (10)	0.27584 (12)	0.0318 (3)
O1W	0.58488 (19)	0.45145 (9)	0.32058 (11)	0.0393 (3)
H1W	0.5510	0.3858	0.2905	0.059*
H2W	0.7096	0.4775	0.3151	0.059*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
C1	0.0229 (6)	0.0215 (6)	0.0268 (6)	0.0016 (5)	0.0055 (5)	0.0021 (5)
C2	0.0237 (6)	0.0221 (6)	0.0267 (6)	−0.0007 (5)	0.0059 (5)	0.0014 (5)
C3	0.0350 (7)	0.0238 (7)	0.0409 (8)	−0.0016 (6)	0.0050 (6)	0.0051 (6)
C4	0.0445 (9)	0.0267 (7)	0.0491 (9)	−0.0124 (6)	0.0082 (7)	0.0013 (6)
C5	0.0299 (7)	0.0422 (9)	0.0407 (8)	−0.0135 (6)	0.0019 (6)	−0.0014 (7)
C6	0.0243 (6)	0.0366 (8)	0.0327 (7)	−0.0011 (6)	0.0020 (5)	0.0024 (6)
Mn1	0.02613 (16)	0.01760 (16)	0.03133 (17)	0.00182 (10)	0.00463 (12)	0.00246 (10)
N1	0.0235 (5)	0.0237 (5)	0.0277 (5)	0.0000 (4)	0.0047 (4)	0.0021 (4)
N2	0.0222 (5)	0.0227 (6)	0.0342 (6)	−0.0018 (4)	0.0026 (5)	0.0001 (4)
N3	0.0239 (6)	0.0332 (7)	0.0400 (7)	−0.0042 (5)	0.0023 (5)	−0.0009 (5)
N4	0.0246 (6)	0.0402 (7)	0.0407 (7)	−0.0016 (5)	0.0012 (5)	0.0044 (6)
N5	0.0240 (6)	0.0316 (6)	0.0363 (6)	0.0023 (5)	0.0029 (5)	0.0075 (5)
O1W	0.0422 (6)	0.0340 (6)	0.0472 (6)	−0.0123 (5)	0.0213 (5)	−0.0121 (5)

Geometric parameters (Å, º)

C1—N5	1.3325 (17)	C6—H6	0.9300
C1—N2	1.3350 (18)	Mn1—O1W^i	2.1954 (14)
C1—C2	1.4670 (19)	Mn1—O1W	2.1954 (14)
C2—N1	1.3478 (17)	Mn1—N2^i	2.2388 (14)
C2—C3	1.387 (2)	Mn1—N2	2.2388 (14)
C3—C4	1.383 (2)	Mn1—N1^i	2.2538 (16)
C3—H3	0.9300	Mn1—N1	2.2538 (16)
C4—C5	1.381 (2)	N2—N3	1.3438 (17)
C4—H4	0.9300	N3—N4	1.3122 (19)
C5—C6	1.382 (2)	N4—N5	1.3449 (18)
C5—H5	0.9300	O1W—H1W	0.8597
C6—N1	1.3367 (18)	O1W—H2W	0.8507
N5—C1—N2	111.33 (12)	N2^i—Mn1—N2	180.0
N5—C1—C2	126.65 (12)	O1W^i—Mn1—N1^i	91.80 (5)
N2—C1—C2	122.03 (11)	O1W—Mn1—N1^i	88.20 (5)
N1—C2—C3	122.30 (13)	N2^i—Mn1—N1^i	75.47 (5)
N1—C2—C1	115.11 (12)	N2—Mn1—N1^i	104.53 (5)
C3—C2—C1	122.59 (12)	O1W^i—Mn1—N1	88.20 (5)
C4—C3—C2	118.56 (14)	O1W—Mn1—N1	91.80 (5)
C4—C3—H3	120.7	N2^i—Mn1—N1	104.53 (5)
C2—C3—H3	120.7	N2—Mn1—N1	75.47 (5)
C5—C4—C3	119.57 (14)	N1^i—Mn1—N1	180.0
C5—C4—H4	120.2	C6—N1—C2	118.14 (12)
C3—C4—H4	120.2	C6—N1—Mn1	126.70 (10)
C4—C5—C6	118.32 (14)	C2—N1—Mn1	115.00 (9)
C4—C5—H5	120.8	C1—N2—N3	105.11 (11)
C6—C5—H5	120.8	C1—N2—Mn1	112.29 (9)
N1—C6—C5	123.09 (14)	N3—N2—Mn1	142.51 (9)
N1—C6—H6	118.5	N4—N3—N2	109.13 (12)
C5—C6—H6	118.5	N3—N4—N5	109.55 (12)
O1W^i—Mn1—O1W	180.0	C1—N5—N4	104.88 (12)
O1W^i—Mn1—N2^i	88.95 (5)	Mn1—O1W—H1W	118.4
O1W—Mn1—N2^i	91.05 (5)	Mn1—O1W—H2W	114.0
O1W^i—Mn1—N2	91.05 (5)	H1W—O1W—H2W	116.5
O1W—Mn1—N2	88.95 (5)

Symmetry code: (i) −x+1, −y+1, −z+1.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O1W—H2W···N3^ii	0.85	2.03	2.864 (2)	169
O1W—H1W···N5^iii	0.86	1.93	2.788 (2)	175

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