Dibromidobis(2-methyl-5-phenyl-s-triazolo[3,4-b][1,3,4]thia­diazole-κN)­nickel(II)

The title complex, [NiBr₂(C₁₀H₈N₄S)₂], is a mononuclear mol­ecule consisting of an Ni^II ion, two 2-methyl-5-phenyl-s-triazolo[3,4-b][1,3,4]thia­diazole ligands and two bromide ligands. The Ni^II atom, located on a center of symmetry, displays a square-planar coordination geometry. Inter­molecular C—H...Br hydrogen bonds and π–π contacts [centroid–centroid distance = 3.58 (6) Å] stabilize the supra­molecular structure.

Key indicators

• Single-crystal X-ray study
• T = 298 K
• Mean [sigma](C-C) = 0.006 Å
• R factor = 0.044
• wR factor = 0.116
• Data-to-parameter ratio = 15.7

checkCIF/PLATON results

No syntax errors found



Alert level A
PLAT029_ALERT_3_A _diffrn_measured_fraction_theta_full Low .......       0.92

Author Response: The diffraction was weak, but in spite of the rather low completness (92% at \q = 25\%) the ratio of "observed" data to total number of parameters was reasonable (10.5).

Alert level B
PLAT022_ALERT_3_B Ratio Unique / Expected Reflections too Low ....       0.89
PLAT232_ALERT_2_B Hirshfeld Test Diff (M-X)  Br1    -   Ni1     ..      13.56 su

Alert level C
RINTA01_ALERT_3_C  The value of Rint is greater than 0.10
            Rint given   0.101
PLAT020_ALERT_3_C The value of Rint is greater than 0.10 .........       0.10
PLAT125_ALERT_4_C No _symmetry_space_group_name_Hall Given .......          ?
PLAT242_ALERT_2_C Check Low       Ueq as Compared to Neighbors for        Ni1

Alert level G
PLAT794_ALERT_5_G Check Predicted Bond Valency for Ni1         (2)       2.15

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

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

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S1. Comment

The molecular structure of 2-methyl-5-phenyl-s-triazolo(3,4- b)-1,3,4-thiadiazole (Fornies-Marquina et al., 1974) and its substituted derivatives (Huang et al., 2005; Naveen, et al., 2006) have been reported; however, no example of any metal complex of the ligand are known to date. In this paper, we present the crystal structure of the title compound [NiBr₂(C₁₀H₈N₄S)₂] (I), a Ni complex obtained by the reaction of 2-methyl-5-phenyl-s-triazolo(3,4- b)-1,3,4-thiadiazole with nickel sulfate and sodium bromide in a methanol solution.

As illustrated in Fig. 1, the Ni^II atom is a neutral mononuclear molecule which lies on a centre of symmetry and displays a square planar coordination geometry, the four coordinating atoms being two N atoms from two 2-methyl-5-phenyl-s-triazolo(3,4- b)-1,3,4-thiadiazole, and two bromine atoms (Table 1). The structural components are connected through two types of interactions:

1) C—H···Br hydrogen bonds (involving the C atoms of 2-methyl-5-phenyl-s-triazolo(3,4- b)-1,3,4-thiadiazole) as donors and the bromine atoms as acceptors (Table 2), and

2) π-π stacking interactions between the phenyl and triazolo rings, with a centroid-centroid distance of 3.58 (6) Å, forming a supramolecular network structure.

Besides, there is an intramolecular C—H···N hydrogen bond (Table 2) linking the fused ring system and the phenyl plane and promoting their near coplanarity (Dihedral angle: 2.2 (5)°).

Related literature

For related literature, see: Fornies-Marquina et al. (1974); Huang et al. (2005); Naveen et al. (2006).

S2. Experimental

The title complex was prepared by adding nickel sulfate (0.0155 g,0.1 mmol) and sodium bromide(0.0205 g, 0.2 mmol) to a CH₃CN solution (12 ml) of 2-methyl-5-phenyl-s-triazolo(3,4- b)-1,3,4-thiadiazole (0.045 g, 0.2 mmol). The resulting solution was filtered, and green block crystals were obtained at room temperature on slow evaporation of the solvent over three weeks.

S3. Refinement

The diffraction was weak, but in spite of the rather low completness (92% at θ = 25°) the ratio of "observed" data to total number of parameters was reasonable (10.5). Carbon-bound H atoms were placed at calculated positions and were treated as riding on the parent C atoms with C—H = 0.93–0.97 and with U_iso(H) = 1.2.

Computing details

Data collection: APEX2 (Bruker, 2000); cell refinement: SAINT (Bruker, 1999); data reduction: SAINT (Bruker, 1999); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL (Bruker, 1998); software used to prepare material for publication: SHELXTL (Bruker, 1998).

Figures

Fig. 1. The molecular structure of (I), showing the atomic numbering scheme. Probability displacement ellipsoids are drawn at the 30% level. In the centrosymmetric molecule, unlabelled atoms are related to labelled ones by the symmetry operator 1 - x, 1 - y, -z.

Dibromidobis(2-methyl-5-phenyl-s-triazolo[3,4-b][1,3,4]thiadiazole- κN)nickel(II)

Crystal data

[NiBr2(C10H8N4S)2]	Z = 1
Mr = 651.06	F(000) = 322
Triclinic, P1	Dx = 1.855 Mg m^−3
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 6.8286 (10) Å	Cell parameters from 2383 reflections
b = 8.5231 (13) Å	θ = 1.9–27.5°
c = 11.3654 (16) Å	µ = 4.47 mm^−1
α = 98.442 (2)°	T = 298 K
β = 105.614 (3)°	Block, green
γ = 108.859 (2)°	0.25 × 0.20 × 0.14 mm
V = 582.69 (15) Å^3

Data collection

Bruker APEX II area-detector diffractometer	2383 independent reflections
Radiation source: fine-focus sealed tube	1595 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.101
φ and ω scans	θmax = 27.5°, θmin = 1.9°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −8→8
Tmin = 0.37, Tmax = 0.53	k = −11→10
4173 measured reflections	l = −13→14

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)] = 0.044	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.116	H-atom parameters constrained
S = 0.89	w = 1/[σ^2(Fo^2) + (0.0555P)^2] where P = (Fo^2 + 2Fc^2)/3
2383 reflections	(Δ/σ)max < 0.001
152 parameters	Δρmax = 0.70 e Å^−3
0 restraints	Δρmin = −0.93 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
Br1	0.85222 (9)	0.72697 (7)	0.06809 (5)	0.0707 (2)
Ni1	0.5000	0.5000	0.0000	0.0321 (2)
S1	0.3986 (2)	0.08844 (13)	0.13109 (10)	0.0434 (3)
N1	0.5616 (6)	0.4522 (4)	0.1689 (3)	0.0392 (8)
N2	0.6704 (6)	0.5816 (4)	0.2827 (3)	0.0392 (8)
N3	0.6002 (6)	0.3343 (4)	0.3279 (3)	0.0330 (7)
N4	0.5781 (6)	0.1933 (4)	0.3771 (3)	0.0383 (8)
C1	0.8738 (8)	0.7807 (6)	0.5409 (4)	0.0435 (10)
H1	0.8615	0.8379	0.4772	0.052*
C2	0.9710 (8)	0.8729 (6)	0.6677 (4)	0.0504 (12)
H2	1.0233	0.9921	0.6892	0.060*
C3	0.9889 (8)	0.7861 (6)	0.7604 (4)	0.0497 (12)
H3	1.0536	0.8479	0.8447	0.060*
C5	0.8172 (8)	0.5181 (6)	0.6055 (4)	0.0424 (10)
H4	0.7674	0.3990	0.5852	0.051*
C6	0.7950 (7)	0.6011 (5)	0.5107 (4)	0.0340 (9)
C4	0.9134 (8)	0.6106 (6)	0.7314 (4)	0.0511 (12)
H6	0.9264	0.5541	0.7954	0.061*
C8	0.5192 (7)	0.3049 (5)	0.2004 (4)	0.0358 (9)
C9	0.4777 (8)	0.0564 (5)	0.2839 (4)	0.0425 (10)
C10	0.4262 (9)	−0.1189 (6)	0.3024 (5)	0.0629 (15)
H17A	0.4750	−0.1124	0.3911	0.094*
H17B	0.4999	−0.1755	0.2613	0.094*
H17C	0.2703	−0.1826	0.2667	0.094*
C7	0.6932 (7)	0.5085 (5)	0.3759 (4)	0.0327 (9)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Br1	0.0605 (4)	0.0744 (4)	0.0384 (3)	−0.0131 (3)	0.0004 (2)	0.0214 (3)
Ni1	0.0408 (4)	0.0294 (4)	0.0194 (3)	0.0069 (3)	0.0077 (3)	0.0064 (3)
S1	0.0519 (7)	0.0362 (6)	0.0349 (5)	0.0125 (5)	0.0104 (5)	0.0061 (5)
N1	0.047 (2)	0.0380 (19)	0.0244 (16)	0.0099 (17)	0.0081 (16)	0.0064 (14)
N2	0.047 (2)	0.0352 (18)	0.0271 (17)	0.0096 (16)	0.0096 (17)	0.0046 (14)
N3	0.040 (2)	0.0342 (18)	0.0280 (16)	0.0153 (15)	0.0126 (16)	0.0114 (14)
N4	0.043 (2)	0.043 (2)	0.0358 (19)	0.0202 (17)	0.0140 (17)	0.0176 (16)
C1	0.048 (3)	0.046 (3)	0.032 (2)	0.016 (2)	0.011 (2)	0.0063 (19)
C2	0.047 (3)	0.053 (3)	0.037 (2)	0.012 (2)	0.009 (2)	−0.003 (2)
C3	0.043 (3)	0.071 (3)	0.029 (2)	0.020 (2)	0.011 (2)	0.000 (2)
C5	0.049 (3)	0.044 (2)	0.032 (2)	0.016 (2)	0.014 (2)	0.0079 (18)
C6	0.035 (2)	0.042 (2)	0.0276 (19)	0.0158 (19)	0.0139 (19)	0.0076 (17)
C4	0.057 (3)	0.070 (3)	0.028 (2)	0.022 (3)	0.016 (2)	0.016 (2)
C8	0.038 (2)	0.039 (2)	0.029 (2)	0.0118 (19)	0.0128 (19)	0.0084 (17)
C9	0.043 (3)	0.042 (2)	0.045 (2)	0.019 (2)	0.013 (2)	0.015 (2)
C10	0.073 (4)	0.047 (3)	0.062 (3)	0.024 (3)	0.006 (3)	0.021 (3)
C7	0.033 (2)	0.037 (2)	0.0283 (19)	0.0124 (18)	0.0100 (18)	0.0096 (17)

Geometric parameters (Å, º)

Ni1—Br1	2.3826 (6)	C1—H1	0.9300
Ni1—N1	1.984 (3)	C2—C3	1.375 (6)
Ni1—N1^i	1.984 (3)	C2—H2	0.9300
Ni1—Br1^i	2.3826 (6)	C3—C4	1.369 (7)
S1—C8	1.716 (4)	C3—H3	0.9300
S1—C9	1.765 (4)	C5—C6	1.375 (6)
N1—C8	1.319 (5)	C5—C4	1.389 (6)
N1—N2	1.405 (4)	C5—H4	0.9300
N2—C7	1.305 (5)	C6—C7	1.473 (5)
N3—C8	1.358 (5)	C4—H6	0.9300
N3—C7	1.368 (5)	C9—C10	1.481 (6)
N3—N4	1.380 (4)	C10—H17A	0.9600
N4—C9	1.297 (6)	C10—H17B	0.9600
C1—C2	1.396 (6)	C10—H17C	0.9600
C1—C6	1.402 (6)
N1—Ni1—N1^i	180.00 (19)	C6—C5—C4	120.5 (4)
N1—Ni1—Br1	90.80 (10)	C6—C5—H4	119.7
N1^i—Ni1—Br1	89.20 (10)	C4—C5—H4	119.7
N1—Ni1—Br1^i	89.20 (10)	C5—C6—C1	119.9 (4)
N1^i—Ni1—Br1^i	90.80 (10)	C5—C6—C7	122.5 (4)
Br1—Ni1—Br1^i	180.0	C1—C6—C7	117.6 (4)
C8—S1—C9	87.73 (19)	C3—C4—C5	119.3 (4)
C8—N1—N2	106.4 (3)	C3—C4—H6	120.3
C8—N1—Ni1	130.3 (3)	C5—C4—H6	120.3
N2—N1—Ni1	123.3 (2)	N1—C8—N3	109.8 (3)
C7—N2—N1	108.2 (3)	N1—C8—S1	140.1 (3)
C8—N3—C7	106.6 (3)	N3—C8—S1	110.1 (3)
C8—N3—N4	117.5 (3)	N4—C9—C10	122.8 (4)
C7—N3—N4	135.9 (3)	N4—C9—S1	116.4 (3)
C9—N4—N3	108.2 (3)	C10—C9—S1	120.8 (4)
C2—C1—C6	119.2 (4)	C9—C10—H17A	109.5
C2—C1—H1	120.4	C9—C10—H17B	109.5
C6—C1—H1	120.4	H17A—C10—H17B	109.5
C3—C2—C1	119.5 (4)	C9—C10—H17C	109.5
C3—C2—H2	120.3	H17A—C10—H17C	109.5
C1—C2—H2	120.3	H17B—C10—H17C	109.5
C4—C3—C2	121.5 (4)	N2—C7—N3	109.0 (3)
C4—C3—H3	119.2	N2—C7—C6	124.7 (4)
C2—C3—H3	119.2	N3—C7—C6	126.3 (3)

Symmetry code: (i) −x+1, −y+1, −z.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
C10—H17C···Br1^ii	0.96	2.90	3.769 (5)	150
C5—H4···N4	0.93	2.45	3.123 (6)	129

Symmetry code: (ii) x−1, y−1, z.