Retracted: Diazido­bis(2,2′-biimidazole)manganese(II)

In the title compound, [Mn(N₃)₂(C₆H₆N₄)₂], the Mn atom (site symmetry ) is bonded to two azide ions and two bidentate biimidizole ligands, resulting in a slightly distorted octa­hedral MnN₆ geometry for the metal ion. In the crystal structure, N—H...N hydrogen bonds help to consolidate the packing.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.005 Å
• R factor = 0.039
• wR factor = 0.131
• Data-to-parameter ratio = 11.5

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT029_ALERT_3_C _diffrn_measured_fraction_theta_full Low .......       0.98
PLAT232_ALERT_2_C Hirshfeld Test Diff (M-X)  Mn1    --  N5      ..       6.72 su

Alert level G
PLAT860_ALERT_3_G Note: Number of Least-Squares Restraints .......          2
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
   2 ALERT level C = Check and explain
   3 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
   2 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 study of coordination compounds including one-, two- and three-dimensional infinite frameworks has been expanding rapidly because of their fascinating structural diversity and potential application as functional materials. To date, much of the work has been focused on coordination polymers with semi-rigid ligands, such as 4,4'-bipyridine, pyrazine and their analogues. In this paper, we report the structure of the molecular title compound, (I), with the use of the 2,2'-biimidazole bridging ligand (Hester et al., 1997).

As shown in Fig. 1, the Mn ion in (I) occupies an inversion centre, and is hexacoordinated by six N atoms from two chelating ligands of H₂bim (biimidizole; C₆H₆N₄) and two azide ions, showing a slightly distorted MnN₆ octahedral geometry (Table 1).

In the crystal of (I), N—H···N hydrogen bonds, one of which is bifurcated (Table 2), help to consolidate the packing.

Related literature

For a related structure, see: Hester et al. (1997).

S2. Experimental

A mixture of manganese(II) perchlorate hexahydrate (1 mmol), 2,2'-biimidazoline (2 mmol) and Na₃N₃ (2 mmol) in 20 ml ethanol was reflued for several hours. The cooled solution was filtered and the filtrate was kept in an ice box for about one week. Yellow blocks of (I) were obtained with a yield of 10%. Anal. Calc. for C₁₂H₁₂MnN₁₄: C 35.35, H 2.95, N 48.12%; Found: C 35.31, H 2.92, N 48.06%.

S3. Refinement

The N-bound H atoms were located in a difference map and their positions were freely refined with U_iso(H) = 1.2U_eq(N). The C-bound H atoms were placed in calculated positions (C—H = 0.93 Å) and refined as riding with U_iso(H) = 1.2U_eq(C).

Computing details

Data collection: APEX2 (Bruker, 2004); cell refinement: SAINT-Plus (Bruker, 2004); data reduction: SAINT-Plus (Bruker, 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures

Fig. 1. The molecular structure of (I), drawn with 30% probability displacement ellipsoids for the non-hydrogen atoms. Symmetry code: (i) 3/2-x, 3/2-y, 1-z.

Diazidobis(2,2'-biimidazole)manganese(II)

Crystal data

[Mn(N3)2(C6H6N4)2]	F(000) = 828
Mr = 407.30	Dx = 1.705 Mg m^−3
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2yc	Cell parameters from 1505 reflections
a = 12.5097 (10) Å	θ = 2.8–25.9°
b = 8.9728 (5) Å	µ = 0.87 mm^−1
c = 14.1416 (10) Å	T = 293 K
β = 91.883 (10)°	Block, yellow
V = 1586.50 (19) Å^3	0.40 × 0.26 × 0.20 mm
Z = 4

Data collection

Bruker APEXII CCD diffractometer	1505 independent reflections
Radiation source: fine-focus sealed tube	1250 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.022
ϕ and ω scans	θmax = 25.9°, θmin = 2.8°
Absorption correction: multi-scan (SADABS; Bruker, 2004)	h = −1→15
Tmin = 0.723, Tmax = 0.846	k = −1→10
1966 measured reflections	l = −17→17

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)] = 0.038	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.131	H atoms treated by a mixture of independent and constrained refinement
S = 1.00	w = 1/[σ^2(Fo^2) + (0.081P)^2 + 1.7249P] where P = (Fo^2 + 2Fc^2)/3
1505 reflections	(Δ/σ)max = 0.024
131 parameters	Δρmax = 0.49 e Å^−3
2 restraints	Δρmin = −0.25 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	0.7500	0.7500	0.5000	0.0486 (5)
C1	0.5842 (3)	0.5617 (4)	0.3628 (2)	0.0572 (8)
H1	0.5711	0.6280	0.3132	0.069*
C2	0.5366 (3)	0.4245 (4)	0.3721 (2)	0.0585 (9)
H2	0.4865	0.3819	0.3303	0.070*
C3	0.6462 (2)	0.4631 (4)	0.4891 (2)	0.0482 (7)
C4	0.7106 (2)	0.4562 (4)	0.5744 (2)	0.0489 (7)
C5	0.8223 (3)	0.5322 (4)	0.6783 (2)	0.0580 (8)
H5	0.8713	0.5915	0.7118	0.070*
C6	0.7940 (3)	0.3903 (4)	0.7030 (2)	0.0610 (9)
H6	0.8195	0.3369	0.7554	0.073*
N1	0.5763 (2)	0.3633 (3)	0.45300 (18)	0.0534 (7)
H1A	0.546 (3)	0.270 (3)	0.474 (3)	0.064*
N2	0.6529 (2)	0.5851 (3)	0.43706 (17)	0.0520 (7)
N3	0.7688 (2)	0.5733 (3)	0.59802 (18)	0.0525 (7)
N4	0.7220 (2)	0.3432 (3)	0.63640 (19)	0.0551 (7)
H4	0.680 (3)	0.255 (3)	0.634 (3)	0.066*
N5	0.8833 (2)	0.6634 (3)	0.4268 (2)	0.0529 (7)
N6	0.8963 (2)	0.5320 (3)	0.4212 (2)	0.0552 (7)
N7	0.9109 (3)	0.4018 (3)	0.4143 (2)	0.0723 (9)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Mn1	0.0504 (12)	0.0400 (13)	0.0550 (13)	0.0096 (10)	−0.0016 (10)	−0.0034 (10)
C1	0.0542 (18)	0.069 (2)	0.0481 (17)	−0.0156 (16)	−0.0081 (14)	0.0038 (15)
C2	0.0551 (18)	0.070 (2)	0.0495 (17)	−0.0171 (16)	−0.0056 (14)	−0.0031 (15)
C3	0.0485 (16)	0.0500 (18)	0.0462 (15)	−0.0087 (13)	0.0012 (12)	−0.0003 (13)
C4	0.0481 (15)	0.0480 (17)	0.0503 (16)	−0.0051 (13)	0.0012 (13)	0.0026 (13)
C5	0.0598 (19)	0.061 (2)	0.0527 (17)	−0.0041 (16)	−0.0095 (14)	0.0033 (15)
C6	0.064 (2)	0.067 (2)	0.0510 (18)	−0.0005 (18)	−0.0087 (15)	0.0092 (16)
N1	0.0539 (15)	0.0539 (16)	0.0525 (15)	−0.0158 (13)	0.0020 (12)	−0.0012 (12)
N2	0.0512 (14)	0.0569 (17)	0.0477 (14)	−0.0117 (13)	−0.0035 (11)	0.0045 (12)
N3	0.0519 (15)	0.0543 (16)	0.0508 (14)	−0.0088 (13)	−0.0063 (11)	0.0042 (12)
N4	0.0600 (16)	0.0524 (16)	0.0524 (14)	−0.0079 (13)	−0.0021 (12)	0.0077 (12)
N5	0.0585 (16)	0.0552 (17)	0.0444 (14)	−0.0006 (14)	−0.0080 (12)	−0.0089 (12)
N6	0.0525 (15)	0.0540 (18)	0.0585 (16)	−0.0129 (13)	−0.0071 (12)	0.0069 (13)
N7	0.073 (2)	0.0512 (18)	0.092 (2)	−0.0078 (15)	−0.0108 (17)	0.0073 (16)

Geometric parameters (Å, º)

Mn1—N2	2.094 (3)	C3—C4	1.430 (4)
Mn1—N2^i	2.094 (3)	C4—N3	1.315 (4)
Mn1—N3^i	2.114 (3)	C4—N4	1.345 (4)
Mn1—N3	2.114 (3)	C5—N3	1.350 (4)
Mn1—N5	2.138 (3)	C5—C6	1.370 (5)
Mn1—N5^i	2.138 (3)	C5—H5	0.9300
C1—N2	1.351 (4)	C6—N4	1.350 (4)
C1—C2	1.375 (5)	C6—H6	0.9300
C1—H1	0.9300	N1—H1A	0.966 (18)
C2—N1	1.349 (4)	N4—H4	0.952 (19)
C2—H2	0.9300	N5—N6	1.193 (4)
C3—N2	1.323 (4)	N6—N7	1.187 (4)
C3—N1	1.340 (4)
N2—Mn1—N2^i	180.0)	N3—C4—N4	113.0 (3)
N2—Mn1—N3^i	101.59 (10)	N3—C4—C3	118.2 (3)
N2^i—Mn1—N3^i	78.41 (10)	N4—C4—C3	128.8 (3)
N2—Mn1—N3	78.41 (10)	N3—C5—C6	110.1 (3)
N2^i—Mn1—N3	101.59 (10)	N3—C5—H5	125.0
N3^i—Mn1—N3	180.0	C6—C5—H5	125.0
N2—Mn1—N5	89.31 (11)	N4—C6—C5	106.5 (3)
N2^i—Mn1—N5	90.69 (11)	N4—C6—H6	126.7
N3^i—Mn1—N5	91.53 (11)	C5—C6—H6	126.7
N3—Mn1—N5	88.47 (11)	C3—N1—C2	105.6 (3)
N2—Mn1—N5^i	90.69 (11)	C3—N1—H1A	135 (3)
N2^i—Mn1—N5^i	89.31 (11)	C2—N1—H1A	119 (3)
N3^i—Mn1—N5^i	88.47 (11)	C3—N2—C1	104.7 (3)
N3—Mn1—N5^i	91.53 (11)	C3—N2—Mn1	113.26 (19)
N5—Mn1—N5^i	180.0	C1—N2—Mn1	141.7 (2)
N2—C1—C2	109.3 (3)	C4—N3—C5	104.5 (3)
N2—C1—H1	125.3	C4—N3—Mn1	112.6 (2)
C2—C1—H1	125.3	C5—N3—Mn1	142.9 (2)
N1—C2—C1	107.3 (3)	C4—N4—C6	105.8 (3)
N1—C2—H2	126.4	C4—N4—H4	124 (3)
C1—C2—H2	126.4	C6—N4—H4	130 (3)
N2—C3—N1	113.1 (3)	N6—N5—Mn1	120.1 (2)
N2—C3—C4	117.4 (3)	N7—N6—N5	178.6 (4)
N1—C3—C4	129.5 (3)

Symmetry code: (i) −x+3/2, −y+3/2, −z+1.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1A···N7^ii	0.97 (2)	2.26 (3)	3.031 (4)	136 (3)
N1—H1A···N5^iii	0.97 (2)	2.33 (4)	3.021 (4)	127 (3)
N4—H4···N7^ii	0.95 (2)	1.92 (2)	2.834 (4)	160 (4)

Symmetry codes: (ii) −x+3/2, −y+1/2, −z+1; (iii) x−1/2, y−1/2, z.