Bis[μ-2-(3-pyrid­yl)-1H-benzimidazole-κ²N:N′]disilver(I) dinitrate

The title compound, [Ag₂(C₁₂H₉N₃)₂](NO₃)₂, was prepared under hydro­thermal conditions. The structure consists of binuclear complex cations and nitrate anions. The two Ag^I atoms, each in a geometry somewhat distorted from linear, are bridged by two 2-(3-pyrid­yl)benzimidazole ligands via pyridyl and imidazole N atoms, forming a centrosymmetric cyclic dimer. A three-dimensional network is constructed via N—H...O hydrogen bonds and weak Ag...O inter­actions [Ag...O = 2.686 (13)–2.847 (7) Å], as well as by offset π–π inter­actions between the pyridyl and imidazolyl rings with a nearest atom-to-atom distance of 3.40 (2) Å and a centroid-to-centroid distance of 4.06 (3) Å.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.004 Å
• R factor = 0.023
• wR factor = 0.063
• Data-to-parameter ratio = 15.2

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT029_ALERT_3_C _diffrn_measured_fraction_theta_full Low .......       0.98
PLAT244_ALERT_4_C Low   'Solvent' Ueq as Compared to Neighbors for         N4

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
PLAT794_ALERT_5_G Check Predicted Bond Valency for Ag1         (9)       0.81

   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
   0 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
   1 ALERT type 4 Improvement, methodology, query or suggestion
   1 ALERT type 5 Informative message, check

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S1. Comment

The 2-(3-pyridyl)benzimidazole ligand acts as terminal (Chen et al., 2005) or bidentate ligand (Su et al., 1999) in metal complexes. Herein we report the synthesis and structure of a binuclear silver(I) complex with 2-(3-pyridyl)benzimidazole.

In the title compound, the centrosymmetric binuclear cyclic complex contains two Ag^I atoms bridged by two 2-(3-pyridyl)benzimidazole ligands via pyridyl and imidazole N atoms in a head-to-end mode (Fig. 1). The Ag^I atom is in an approximate linear coordination geometry. The nitrate anion acts as a counter ion and is weakly coordinated to Ag^I atoms [Ag1···O1 = 2.686 (13) Å, Ag1···O3 = 2.847 (7)Å and Ag1···O2ⁱ = 2.782 (5) Å; symmetry code: (i) 1 - x, 2 - y, 2 - z]. The Ag1···O1 and Ag1···O3 interactions as well as N3—H···O1 hydrogen bonds connect the binuclear units into a one-dimensional chain (Fig. 2). Crystal packing is stabilized by the Ag1···O2ⁱ interactions and offset π–π interactions between the chains (Fig. 3).

Related literature

For related literature, see: Alcade et al. (1992); Chen et al. (2005); Su et al. (1999).

S2. Experimental

A solution of AgNO₃ (0.104 g, 0.61 mmol), 2-(3-pyridyl)benzimidazole (Alcade et al., 1992) (0.14 g, 0.61 mmol) and H₂O (15 ml) was stirred under ambient condition. The mixture was sealed in a 25 ml Teflon-lined stainless steel vessel, heated at 383 K for 3 d and then cooled to room temperature. The resulting product was collected by filtration, washed with distilled water and dried in air (yield 80%).

S3. Refinement

H atoms were positioned geometrically and refined as riding atoms, with C—H = 0.93 and N—H = 0.86Å and U_iso(H) = 1.2U_eq(C,N).

Computing details

Data collection: CrystalClear (Rigaku, 2000); cell refinement: CrystalClear (Rigaku, 2000); data reduction: CrystalClear (Rigaku, 2000); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL (Siemens, 1994); software used to prepare material for publication: SHELXL97 (Sheldrick, 1997).

Figures

	Fig. 1. The structure of the title compound. Displacement ellipsoids are drawn at the 30% probability level. [Symmetry code: (i) 2 - x, 2 - y, 2 - z.]
	Fig. 2. A view of the one-dimensional chain. H atoms have been omitted for clarity. Hydrogen bonds and weak Ag···O interactions are shown as dashed lines.
	Fig. 3. The crystal packing of the title compound. Hydrogen bonds and weak Ag···O interactions are shown as dashed lines.

Bis[µ-2-(3-pyridyl)-1H-benzimidazole-κ²N:N']disilver(I) dinitrate

Crystal data

[Ag2(C12H9N3)2](NO3)2	Z = 1
Mr = 730.20	F(000) = 360
Triclinic, P1	Dx = 1.962 Mg m^−3
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 8.317 (3) Å	Cell parameters from 1908 reflections
b = 9.097 (4) Å	θ = 2.7–27.5°
c = 9.934 (4) Å	µ = 1.64 mm^−1
α = 105.949 (18)°	T = 293 K
β = 96.797 (15)°	Prism, colorless
γ = 116.892 (11)°	0.50 × 0.45 × 0.40 mm
V = 618.2 (5) Å^3

Data collection

Rigaku Mercury CCD diffractometer	2758 independent reflections
Radiation source: fine-focus sealed tube	2586 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.013
ω scans	θmax = 27.5°, θmin = 2.7°
Absorption correction: multi-scan (CrystalClear; Rigaku, 2000)	h = −10→6
Tmin = 0.444, Tmax = 0.528	k = −10→11
4673 measured reflections	l = −12→12

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)] = 0.024	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.063	H-atom parameters constrained
S = 1.04	w = 1/[σ^2(Fo^2) + (0.0396P)^2 + 0.1553P] where P = (Fo^2 + 2Fc^2)/3
2758 reflections	(Δ/σ)max = 0.002
181 parameters	Δρmax = 0.59 e Å^−3
0 restraints	Δρmin = −0.63 e Å^−3

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

	x	y	z	Uiso*/Ueq
Ag1	0.69487 (2)	0.909984 (19)	0.836791 (18)	0.03879 (8)
C1	1.0525 (3)	0.7222 (3)	1.1866 (2)	0.0340 (4)
H1A	1.1496	0.7688	1.2706	0.041*
C2	0.8990 (3)	0.5561 (3)	1.1521 (2)	0.0349 (4)
H2A	0.8944	0.4912	1.2108	0.042*
C3	0.7521 (3)	0.4871 (3)	1.0294 (2)	0.0315 (4)
H3A	0.6471	0.3754	1.0046	0.038*
C4	0.7635 (3)	0.5871 (3)	0.9437 (2)	0.0275 (4)
C5	0.9260 (3)	0.7512 (3)	0.9839 (2)	0.0299 (4)
H5A	0.9368	0.8166	0.9246	0.036*
C6	0.6097 (3)	0.5236 (2)	0.8146 (2)	0.0278 (4)
C7	0.4068 (3)	0.5075 (3)	0.6448 (2)	0.0296 (4)
C8	0.2976 (3)	0.5400 (3)	0.5523 (2)	0.0377 (5)
H8A	0.3261	0.6549	0.5640	0.045*
C9	0.1461 (3)	0.3949 (4)	0.4431 (3)	0.0452 (5)
H9A	0.0698	0.4125	0.3809	0.054*
C10	0.1036 (3)	0.2212 (4)	0.4230 (3)	0.0485 (6)
H10A	0.0002	0.1266	0.3476	0.058*
C11	0.2107 (3)	0.1873 (3)	0.5119 (3)	0.0420 (5)
H11A	0.1839	0.0722	0.4977	0.050*
C12	0.3621 (3)	0.3342 (3)	0.6251 (2)	0.0320 (4)
N1	1.0673 (2)	0.8195 (2)	1.10372 (19)	0.0310 (3)
N2	0.5635 (2)	0.6242 (2)	0.76462 (17)	0.0285 (3)
N3	0.4925 (2)	0.3486 (2)	0.73404 (19)	0.0323 (4)
H3B	0.4988	0.2622	0.7486	0.039*
N4	0.3636 (3)	0.9842 (2)	0.83250 (19)	0.0333 (4)
O1	0.4791 (3)	1.0384 (3)	0.7610 (2)	0.0500 (4)
O2	0.2846 (3)	1.0683 (3)	0.8762 (2)	0.0503 (4)
O3	0.3345 (3)	0.8520 (3)	0.8593 (2)	0.0623 (5)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Ag1	0.03312 (11)	0.02520 (10)	0.05195 (12)	0.01146 (8)	0.00234 (8)	0.01578 (8)
C1	0.0334 (11)	0.0342 (11)	0.0355 (10)	0.0180 (9)	0.0048 (8)	0.0151 (8)
C2	0.0369 (11)	0.0375 (11)	0.0399 (10)	0.0203 (10)	0.0140 (9)	0.0240 (9)
C3	0.0300 (10)	0.0273 (10)	0.0393 (10)	0.0130 (8)	0.0126 (8)	0.0168 (8)
C4	0.0267 (9)	0.0252 (9)	0.0341 (9)	0.0148 (8)	0.0094 (8)	0.0128 (7)
C5	0.0273 (10)	0.0250 (9)	0.0389 (10)	0.0131 (8)	0.0064 (8)	0.0155 (8)
C6	0.0233 (9)	0.0231 (9)	0.0351 (9)	0.0087 (7)	0.0080 (7)	0.0137 (7)
C7	0.0245 (9)	0.0311 (10)	0.0333 (9)	0.0127 (8)	0.0092 (8)	0.0139 (8)
C8	0.0395 (12)	0.0449 (12)	0.0377 (10)	0.0259 (11)	0.0113 (9)	0.0197 (9)
C9	0.0361 (12)	0.0635 (16)	0.0377 (11)	0.0267 (12)	0.0061 (9)	0.0207 (11)
C10	0.0313 (12)	0.0538 (15)	0.0387 (11)	0.0104 (11)	0.0001 (9)	0.0109 (11)
C11	0.0337 (12)	0.0330 (11)	0.0432 (12)	0.0073 (10)	0.0050 (9)	0.0113 (9)
C12	0.0251 (9)	0.0311 (10)	0.0347 (10)	0.0097 (8)	0.0068 (8)	0.0140 (8)
N1	0.0268 (8)	0.0253 (8)	0.0401 (9)	0.0130 (7)	0.0047 (7)	0.0134 (7)
N2	0.0265 (8)	0.0256 (8)	0.0342 (8)	0.0132 (7)	0.0074 (7)	0.0128 (6)
N3	0.0287 (9)	0.0229 (8)	0.0400 (9)	0.0092 (7)	0.0039 (7)	0.0135 (7)
N4	0.0293 (9)	0.0276 (9)	0.0381 (9)	0.0129 (7)	0.0011 (7)	0.0117 (7)
O1	0.0481 (10)	0.0499 (10)	0.0734 (12)	0.0307 (9)	0.0297 (9)	0.0373 (9)
O2	0.0553 (11)	0.0530 (11)	0.0576 (10)	0.0381 (10)	0.0188 (9)	0.0214 (9)
O3	0.0801 (15)	0.0443 (10)	0.0842 (14)	0.0360 (11)	0.0334 (12)	0.0418 (10)

Geometric parameters (Å, º)

Ag1—N2	2.1650 (19)	C7—C8	1.396 (3)
Ag1—N1^i	2.1994 (19)	C8—C9	1.375 (3)
C1—N1	1.343 (3)	C8—H8A	0.9300
C1—C2	1.377 (3)	C9—C10	1.403 (4)
C1—H1A	0.9300	C9—H9A	0.9300
C2—C3	1.381 (3)	C10—C11	1.371 (4)
C2—H2A	0.9300	C10—H10A	0.9300
C3—C4	1.389 (3)	C11—C12	1.397 (3)
C3—H3A	0.9300	C11—H11A	0.9300
C4—C5	1.391 (3)	C12—N3	1.372 (3)
C4—C6	1.467 (3)	N1—Ag1^i	2.1994 (19)
C5—N1	1.336 (3)	N3—O1^ii	2.860 (3)
C5—H5A	0.9300	N3—H3B	0.8600
C6—N2	1.324 (2)	N4—O3	1.226 (3)
C6—N3	1.355 (3)	N4—O2	1.243 (2)
C7—N2	1.389 (3)	N4—O1	1.263 (3)
C7—C12	1.395 (3)
N2—Ag1—N1^i	154.25 (7)	C8—C9—H9A	119.1
N1—C1—C2	122.6 (2)	C10—C9—H9A	119.1
N1—C1—H1A	118.7	C11—C10—C9	121.6 (2)
C2—C1—H1A	118.7	C11—C10—H10A	119.2
C1—C2—C3	119.25 (19)	C9—C10—H10A	119.2
C1—C2—H2A	120.4	C10—C11—C12	116.6 (2)
C3—C2—H2A	120.4	C10—C11—H11A	121.7
C2—C3—C4	119.00 (19)	C12—C11—H11A	121.7
C2—C3—H3A	120.5	N3—C12—C7	105.85 (18)
C4—C3—H3A	120.5	N3—C12—C11	132.0 (2)
C3—C4—C5	118.03 (19)	C7—C12—C11	122.1 (2)
C3—C4—C6	121.62 (18)	C5—N1—C1	118.00 (18)
C5—C4—C6	120.35 (17)	C5—N1—Ag1^i	119.02 (13)
N1—C5—C4	123.10 (18)	C1—N1—Ag1^i	122.89 (14)
N1—C5—H5A	118.4	C6—N2—C7	105.76 (16)
C4—C5—H5A	118.4	C6—N2—Ag1	130.80 (14)
N2—C6—N3	111.85 (18)	C7—N2—Ag1	123.40 (13)
N2—C6—C4	125.91 (18)	C6—N3—C12	107.64 (17)
N3—C6—C4	122.21 (18)	C6—N3—O1^ii	131.71 (14)
N2—C7—C12	108.90 (17)	C12—N3—O1^ii	120.65 (14)
N2—C7—C8	130.6 (2)	C6—N3—H3B	126.2
C12—C7—C8	120.5 (2)	C12—N3—H3B	126.2
C9—C8—C7	117.2 (2)	O3—N4—O2	121.6 (2)
C9—C8—H8A	121.4	O3—N4—O1	119.38 (19)
C7—C8—H8A	121.4	O2—N4—O1	119.00 (19)
C8—C9—C10	121.9 (2)
N1—C1—C2—C3	−1.4 (3)	C4—C5—N1—Ag1^i	−174.98 (14)
C1—C2—C3—C4	0.3 (3)	C2—C1—N1—C5	0.5 (3)
C2—C3—C4—C5	1.6 (3)	C2—C1—N1—Ag1^i	176.94 (16)
C2—C3—C4—C6	−178.09 (18)	N3—C6—N2—C7	0.1 (2)
C3—C4—C5—N1	−2.7 (3)	C4—C6—N2—C7	−177.85 (18)
C6—C4—C5—N1	177.04 (18)	N3—C6—N2—Ag1	−177.81 (12)
C3—C4—C6—N2	148.1 (2)	C4—C6—N2—Ag1	4.2 (3)
C5—C4—C6—N2	−31.7 (3)	C12—C7—N2—C6	−0.2 (2)
C3—C4—C6—N3	−29.7 (3)	C8—C7—N2—C6	178.7 (2)
C5—C4—C6—N3	150.54 (19)	C12—C7—N2—Ag1	177.91 (13)
N2—C7—C8—C9	−178.6 (2)	C8—C7—N2—Ag1	−3.2 (3)
C12—C7—C8—C9	0.2 (3)	N1^i—Ag1—N2—C6	52.9 (2)
C7—C8—C9—C10	−1.0 (3)	N1^i—Ag1—N2—C7	−124.70 (17)
C8—C9—C10—C11	0.3 (4)	N2—C6—N3—C12	0.0 (2)
C9—C10—C11—C12	1.1 (4)	C4—C6—N3—C12	178.08 (17)
N2—C7—C12—N3	0.2 (2)	N2—C6—N3—O1^ii	−178.99 (13)
C8—C7—C12—N3	−178.82 (18)	C4—C6—N3—O1^ii	−0.9 (3)
N2—C7—C12—C11	−179.67 (19)	C7—C12—N3—C6	−0.2 (2)
C8—C7—C12—C11	1.3 (3)	C11—C12—N3—C6	179.7 (2)
C10—C11—C12—N3	178.2 (2)	C7—C12—N3—O1^ii	178.99 (12)
C10—C11—C12—C7	−1.9 (3)	C11—C12—N3—O1^ii	−1.1 (3)
C4—C5—N1—C1	1.6 (3)

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

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N3—H3B···O1^ii	0.86	2.01	2.860 (3)	172

Symmetry code: (ii) x, y−1, z.