As part of a study on the effect of different counter-anions on the self-assembly of coordination complexes, a new dinuclear Ag
I complex, [Ag
2(C
14H
12N
4)
2](CF
3SO
3)
2, with the 3-[3-(2-pyridyl)pyrazol-1-ylmethyl]pyridine (
L) ligand was obtained through the reaction of
L with AgCF
3SO
3. In this complex, each Ag
I center in the centrosymmetric dinuclear complex cation is coordinated by two pyridine and one pyrazole N-atom donor of two inversion-related
L ligands in a trigonal planar geometry. This forms a unique box-like cyclic dimer with an intramolecular nonbonding Ag
Ag separation of 6.379 (7) Å. Weak Ag
CF
3SO
3 and C—H
X (
X = O and F) hydrogen-bonding interactions, together with π–π stacking interactions, link the complex cations along the [001] and [1
0] directions, respectively, generating two different one-dimensional chains and then an overall two-dimensional network of the complex running parallel to the (110) plane. Comparison of the structural differences with previous findings suggests that the presence of different counter-anions plays an important role in the construction of such supramolecular frameworks.
Supporting information
CCDC reference: 609247
The ligand L was synthesized according to the method reported by Liu, Li
et al. (2007). To AgCF3SO3 (0.1 mmol) in a mixed solution of
methanol (15 ml) and acetonitrile (5 ml) was added L (0.1 mmol). A
yellow solid formed, which was filtered off, and the resulting solution was
kept at room temperature. Yellow single crystals suitable for X-ray analysis
were obtained by slow evaporation of the solvent after several days (yield
~30%). Elemental analysis calculated for C15H12AgF3N4O3S: C 36.53,
H 2.45, N 11.36%; found: C 36.41, H 2.56, N 11.42%.
H atoms were included in calculated positions and treated in the subsequent
refinement as riding atoms, with C—H distances of 0.93 (aromatic) or 0.97 Å (methylene), and with Uiso(H) equal to 1.2Ueq(C).
Data collection: SMART (Bruker, 1998); cell refinement: SAINT (Bruker, 1998); data reduction: SAINT (Bruker, 1998); 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) and PLATON (Spek, 2003).
Bis{µ
2-3-[3-(2-pyridyl)pyrazol-1-ylmethyl]pyridine-
κ3N
1:N
2,N
3}disilver(I) bis(trifluoromethanesulfonate)
top
Crystal data top
[Ag2(C14H12N4)2](CF3SO3)2 | Z = 1 |
Mr = 986.44 | F(000) = 488 |
Triclinic, P1 | Dx = 1.848 Mg m−3 |
Hall symbol: -P 1 | Mo Kα radiation, λ = 0.71073 Å |
a = 7.9430 (16) Å | Cell parameters from 3009 reflections |
b = 8.5368 (17) Å | θ = 2.5–26.3° |
c = 13.739 (3) Å | µ = 1.31 mm−1 |
α = 75.64 (3)° | T = 293 K |
β = 86.57 (3)° | Block, yellow |
γ = 79.16 (3)° | 0.30 × 0.28 × 0.25 mm |
V = 886.3 (3) Å3 | |
Data collection top
Bruker SMART CCD area-detector diffractometer | 3099 independent reflections |
Radiation source: fine-focus sealed tube | 2678 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.018 |
ϕ and ω scans | θmax = 25.0°, θmin = 1.5° |
Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | h = −9→7 |
Tmin = 0.68, Tmax = 0.72 | k = −10→10 |
4510 measured reflections | l = −16→15 |
Refinement top
Refinement on F2 | Secondary atom site location: difference Fourier map |
Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
R[F2 > 2σ(F2)] = 0.036 | H-atom parameters constrained |
wR(F2) = 0.095 | w = 1/[σ2(Fo2) + (0.0386P)2 + 1.1251P] where P = (Fo2 + 2Fc2)/3 |
S = 1.07 | (Δ/σ)max = 0.001 |
3099 reflections | Δρmax = 0.59 e Å−3 |
245 parameters | Δρmin = −0.53 e Å−3 |
0 restraints | Extinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
Primary atom site location: structure-invariant direct methods | Extinction coefficient: 0.050 (2) |
Crystal data top
[Ag2(C14H12N4)2](CF3SO3)2 | γ = 79.16 (3)° |
Mr = 986.44 | V = 886.3 (3) Å3 |
Triclinic, P1 | Z = 1 |
a = 7.9430 (16) Å | Mo Kα radiation |
b = 8.5368 (17) Å | µ = 1.31 mm−1 |
c = 13.739 (3) Å | T = 293 K |
α = 75.64 (3)° | 0.30 × 0.28 × 0.25 mm |
β = 86.57 (3)° | |
Data collection top
Bruker SMART CCD area-detector diffractometer | 3099 independent reflections |
Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | 2678 reflections with I > 2σ(I) |
Tmin = 0.68, Tmax = 0.72 | Rint = 0.018 |
4510 measured reflections | |
Refinement top
R[F2 > 2σ(F2)] = 0.036 | 0 restraints |
wR(F2) = 0.095 | H-atom parameters constrained |
S = 1.07 | Δρmax = 0.59 e Å−3 |
3099 reflections | Δρmin = −0.53 e Å−3 |
245 parameters | |
Special details top
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 (Å2) top | x | y | z | Uiso*/Ueq | |
Ag1 | 0.63897 (4) | 0.54485 (4) | 0.77390 (2) | 0.06530 (19) | |
C1 | 0.1667 (5) | 0.4937 (5) | 0.6284 (3) | 0.0550 (9) | |
H1 | 0.0624 | 0.4606 | 0.6257 | 0.066* | |
C2 | 0.2346 (5) | 0.6060 (5) | 0.5562 (3) | 0.0545 (9) | |
H2 | 0.1866 | 0.6655 | 0.4949 | 0.065* | |
C3 | 0.3926 (5) | 0.6128 (4) | 0.5939 (3) | 0.0437 (8) | |
C4 | 0.5237 (5) | 0.7115 (4) | 0.5493 (3) | 0.0427 (8) | |
C5 | 0.5137 (6) | 0.8050 (5) | 0.4513 (3) | 0.0529 (9) | |
H5 | 0.4229 | 0.8067 | 0.4112 | 0.063* | |
C6 | 0.6396 (6) | 0.8956 (5) | 0.4138 (3) | 0.0618 (11) | |
H6 | 0.6342 | 0.9598 | 0.3482 | 0.074* | |
C7 | 0.7720 (6) | 0.8901 (5) | 0.4737 (3) | 0.0623 (11) | |
H7 | 0.8593 | 0.9490 | 0.4493 | 0.075* | |
C8 | 0.7744 (5) | 0.7956 (5) | 0.5712 (3) | 0.0581 (10) | |
H8 | 0.8645 | 0.7934 | 0.6120 | 0.070* | |
C9 | 0.4209 (6) | 0.2801 (5) | 1.0526 (3) | 0.0583 (10) | |
H9 | 0.4943 | 0.2064 | 1.1000 | 0.070* | |
C10 | 0.2303 (5) | 0.5182 (5) | 1.0065 (3) | 0.0549 (9) | |
H10 | 0.1699 | 0.6147 | 1.0205 | 0.066* | |
C11 | 0.4087 (5) | 0.2443 (5) | 0.9613 (3) | 0.0551 (9) | |
H11 | 0.4742 | 0.1497 | 0.9475 | 0.066* | |
C12 | 0.2094 (5) | 0.4888 (5) | 0.9143 (3) | 0.0562 (10) | |
H12 | 0.1345 | 0.5636 | 0.8682 | 0.067* | |
C13 | 0.2989 (4) | 0.3494 (4) | 0.8906 (3) | 0.0426 (8) | |
C14 | 0.2734 (5) | 0.3048 (5) | 0.7935 (3) | 0.0510 (9) | |
H141 | 0.3619 | 0.2127 | 0.7868 | 0.061* | |
H142 | 0.1636 | 0.2695 | 0.7966 | 0.061* | |
C15 | 0.9695 (6) | −0.0467 (6) | 0.8342 (4) | 0.0765 (14) | |
N1 | 0.2785 (4) | 0.4397 (4) | 0.7044 (2) | 0.0459 (7) | |
N2 | 0.4187 (4) | 0.5090 (4) | 0.6841 (2) | 0.0443 (7) | |
N3 | 0.6536 (4) | 0.7071 (4) | 0.6097 (2) | 0.0481 (7) | |
N4 | 0.3330 (4) | 0.4149 (4) | 1.0766 (2) | 0.0472 (7) | |
O1 | 0.8952 (5) | 0.1722 (6) | 0.6747 (3) | 0.1055 (14) | |
O2 | 0.8441 (5) | 0.2540 (5) | 0.8276 (4) | 0.0998 (13) | |
O3 | 0.6633 (4) | 0.0865 (5) | 0.7823 (3) | 0.0782 (9) | |
S1 | 0.82589 (12) | 0.13590 (12) | 0.77311 (7) | 0.0504 (3) | |
F1 | 0.9638 (7) | −0.1678 (5) | 0.7907 (5) | 0.170 (2) | |
F2 | 0.9291 (5) | −0.1092 (6) | 0.9244 (3) | 0.155 (2) | |
F3 | 1.1288 (4) | −0.0274 (4) | 0.8340 (4) | 0.1178 (14) | |
Atomic displacement parameters (Å2) top | U11 | U22 | U33 | U12 | U13 | U23 |
Ag1 | 0.0686 (3) | 0.0816 (3) | 0.0446 (2) | −0.00971 (17) | −0.01809 (15) | −0.01210 (16) |
C1 | 0.045 (2) | 0.066 (3) | 0.056 (2) | −0.0060 (18) | −0.0102 (17) | −0.019 (2) |
C2 | 0.053 (2) | 0.063 (2) | 0.044 (2) | −0.0036 (19) | −0.0133 (17) | −0.0090 (18) |
C3 | 0.0465 (19) | 0.0465 (19) | 0.0376 (18) | 0.0009 (15) | −0.0071 (14) | −0.0147 (15) |
C4 | 0.0467 (19) | 0.0437 (19) | 0.0365 (17) | 0.0014 (15) | −0.0017 (14) | −0.0143 (15) |
C5 | 0.068 (3) | 0.052 (2) | 0.0375 (19) | −0.0023 (19) | −0.0033 (17) | −0.0141 (16) |
C6 | 0.083 (3) | 0.055 (2) | 0.042 (2) | −0.006 (2) | 0.014 (2) | −0.0099 (18) |
C7 | 0.065 (3) | 0.059 (2) | 0.063 (3) | −0.015 (2) | 0.018 (2) | −0.016 (2) |
C8 | 0.052 (2) | 0.060 (2) | 0.062 (3) | −0.0098 (19) | −0.0010 (19) | −0.014 (2) |
C9 | 0.067 (3) | 0.052 (2) | 0.049 (2) | −0.0013 (19) | −0.0144 (19) | −0.0015 (18) |
C10 | 0.057 (2) | 0.054 (2) | 0.050 (2) | 0.0035 (18) | −0.0060 (18) | −0.0160 (18) |
C11 | 0.065 (2) | 0.045 (2) | 0.051 (2) | −0.0018 (18) | −0.0070 (18) | −0.0088 (17) |
C12 | 0.057 (2) | 0.058 (2) | 0.047 (2) | 0.0077 (19) | −0.0155 (18) | −0.0115 (18) |
C13 | 0.0413 (18) | 0.0429 (18) | 0.0431 (18) | −0.0134 (15) | 0.0022 (14) | −0.0055 (15) |
C14 | 0.057 (2) | 0.049 (2) | 0.050 (2) | −0.0177 (17) | −0.0016 (17) | −0.0123 (17) |
C15 | 0.067 (3) | 0.056 (3) | 0.098 (4) | −0.013 (2) | −0.028 (3) | 0.007 (3) |
N1 | 0.0459 (17) | 0.0519 (17) | 0.0416 (16) | −0.0107 (14) | −0.0053 (13) | −0.0121 (13) |
N2 | 0.0463 (16) | 0.0481 (17) | 0.0394 (15) | −0.0098 (13) | −0.0063 (13) | −0.0100 (13) |
N3 | 0.0495 (17) | 0.0497 (17) | 0.0437 (16) | −0.0062 (14) | −0.0033 (13) | −0.0100 (13) |
N4 | 0.0494 (17) | 0.0544 (18) | 0.0373 (15) | −0.0160 (14) | −0.0026 (13) | −0.0050 (13) |
O1 | 0.094 (3) | 0.140 (4) | 0.053 (2) | −0.002 (2) | 0.0086 (18) | 0.014 (2) |
O2 | 0.087 (3) | 0.082 (2) | 0.141 (4) | 0.010 (2) | −0.033 (2) | −0.059 (3) |
O3 | 0.0494 (17) | 0.099 (2) | 0.082 (2) | −0.0110 (16) | −0.0123 (15) | −0.0121 (19) |
S1 | 0.0454 (5) | 0.0531 (5) | 0.0468 (5) | −0.0013 (4) | −0.0057 (4) | −0.0057 (4) |
F1 | 0.180 (5) | 0.069 (2) | 0.264 (7) | 0.024 (3) | −0.110 (4) | −0.057 (3) |
F2 | 0.115 (3) | 0.180 (4) | 0.116 (3) | −0.046 (3) | −0.040 (2) | 0.086 (3) |
F3 | 0.0548 (17) | 0.079 (2) | 0.195 (4) | −0.0034 (15) | −0.033 (2) | 0.015 (2) |
Geometric parameters (Å, º) top
Ag1—N4i | 2.196 (3) | C9—H9 | 0.9300 |
Ag1—N2 | 2.307 (3) | C10—N4 | 1.331 (5) |
Ag1—N3 | 2.346 (3) | C10—C12 | 1.376 (5) |
C1—N1 | 1.345 (5) | C10—H10 | 0.9300 |
C1—C2 | 1.362 (6) | C11—C13 | 1.372 (5) |
C1—H1 | 0.9300 | C11—H11 | 0.9300 |
C2—C3 | 1.402 (5) | C12—C13 | 1.370 (5) |
C2—H2 | 0.9300 | C12—H12 | 0.9300 |
C3—N2 | 1.334 (5) | C13—C14 | 1.509 (5) |
C3—C4 | 1.472 (5) | C14—N1 | 1.463 (5) |
C4—N3 | 1.352 (5) | C14—H141 | 0.9700 |
C4—C5 | 1.383 (5) | C14—H142 | 0.9700 |
C5—C6 | 1.376 (6) | C15—F2 | 1.270 (7) |
C5—H5 | 0.9300 | C15—F3 | 1.306 (6) |
C6—C7 | 1.360 (7) | C15—F1 | 1.325 (7) |
C6—H6 | 0.9300 | C15—S1 | 1.798 (5) |
C7—C8 | 1.381 (6) | N1—N2 | 1.341 (4) |
C7—H7 | 0.9300 | N4—Ag1i | 2.196 (3) |
C8—N3 | 1.336 (5) | O1—S1 | 1.412 (4) |
C8—H8 | 0.9300 | O2—S1 | 1.429 (4) |
C9—N4 | 1.334 (5) | O3—S1 | 1.421 (3) |
C9—C11 | 1.376 (6) | | |
| | | |
N4i—Ag1—N2 | 136.04 (11) | C13—C12—C10 | 120.0 (4) |
N4i—Ag1—N3 | 133.89 (11) | C13—C12—H12 | 120.0 |
N2—Ag1—N3 | 72.05 (11) | C10—C12—H12 | 120.0 |
N1—C1—C2 | 107.2 (3) | C12—C13—C11 | 117.4 (3) |
N1—C1—H1 | 126.4 | C12—C13—C14 | 122.5 (3) |
C2—C1—H1 | 126.4 | C11—C13—C14 | 120.0 (3) |
C1—C2—C3 | 105.2 (3) | N1—C14—C13 | 113.7 (3) |
C1—C2—H2 | 127.4 | N1—C14—H141 | 108.8 |
C3—C2—H2 | 127.4 | C13—C14—H141 | 108.8 |
N2—C3—C2 | 110.3 (3) | N1—C14—H142 | 108.8 |
N2—C3—C4 | 119.5 (3) | C13—C14—H142 | 108.8 |
C2—C3—C4 | 130.2 (3) | H141—C14—H142 | 107.7 |
N3—C4—C5 | 121.7 (4) | F2—C15—F3 | 107.2 (5) |
N3—C4—C3 | 116.4 (3) | F2—C15—F1 | 101.6 (5) |
C5—C4—C3 | 121.9 (3) | F3—C15—F1 | 108.2 (5) |
C6—C5—C4 | 119.3 (4) | F2—C15—S1 | 115.0 (4) |
C6—C5—H5 | 120.3 | F3—C15—S1 | 113.8 (3) |
C4—C5—H5 | 120.3 | F1—C15—S1 | 110.2 (4) |
C7—C6—C5 | 119.3 (4) | N2—N1—C1 | 111.8 (3) |
C7—C6—H6 | 120.4 | N2—N1—C14 | 119.7 (3) |
C5—C6—H6 | 120.4 | C1—N1—C14 | 127.9 (3) |
C6—C7—C8 | 118.8 (4) | C3—N2—N1 | 105.5 (3) |
C6—C7—H7 | 120.6 | C3—N2—Ag1 | 115.2 (2) |
C8—C7—H7 | 120.6 | N1—N2—Ag1 | 136.9 (2) |
N3—C8—C7 | 123.1 (4) | C8—N3—C4 | 117.7 (3) |
N3—C8—H8 | 118.4 | C8—N3—Ag1 | 126.8 (3) |
C7—C8—H8 | 118.4 | C4—N3—Ag1 | 115.4 (2) |
N4—C9—C11 | 123.4 (4) | C10—N4—C9 | 116.6 (3) |
N4—C9—H9 | 118.3 | C10—N4—Ag1i | 123.6 (3) |
C11—C9—H9 | 118.3 | C9—N4—Ag1i | 119.7 (2) |
N4—C10—C12 | 123.0 (4) | O1—S1—O3 | 115.7 (3) |
N4—C10—H10 | 118.5 | O1—S1—O2 | 112.6 (3) |
C12—C10—H10 | 118.5 | O3—S1—O2 | 115.6 (2) |
C13—C11—C9 | 119.5 (4) | O1—S1—C15 | 102.8 (3) |
C13—C11—H11 | 120.3 | O3—S1—C15 | 103.9 (2) |
C9—C11—H11 | 120.3 | O2—S1—C15 | 104.1 (2) |
| | | |
N1—C1—C2—C3 | 0.6 (4) | C1—N1—N2—Ag1 | 162.0 (3) |
C1—C2—C3—N2 | 0.3 (4) | C14—N1—N2—Ag1 | −26.5 (5) |
C1—C2—C3—C4 | 179.7 (4) | N4i—Ag1—N2—C3 | 125.3 (2) |
N2—C3—C4—N3 | −9.0 (5) | N3—Ag1—N2—C3 | −10.3 (2) |
C2—C3—C4—N3 | 171.7 (4) | N4i—Ag1—N2—N1 | −33.8 (4) |
N2—C3—C4—C5 | 171.7 (3) | N3—Ag1—N2—N1 | −169.3 (4) |
C2—C3—C4—C5 | −7.7 (6) | C7—C8—N3—C4 | 0.1 (6) |
N3—C4—C5—C6 | 0.3 (5) | C7—C8—N3—Ag1 | −179.0 (3) |
C3—C4—C5—C6 | 179.6 (3) | C5—C4—N3—C8 | −0.6 (5) |
C4—C5—C6—C7 | 0.5 (6) | C3—C4—N3—C8 | −180.0 (3) |
C5—C6—C7—C8 | −1.1 (6) | C5—C4—N3—Ag1 | 178.5 (3) |
C6—C7—C8—N3 | 0.8 (6) | C3—C4—N3—Ag1 | −0.8 (4) |
N4—C9—C11—C13 | −1.2 (7) | N4i—Ag1—N3—C8 | 47.1 (4) |
N4—C10—C12—C13 | −1.2 (7) | N2—Ag1—N3—C8 | −175.3 (3) |
C10—C12—C13—C11 | −0.6 (6) | N4i—Ag1—N3—C4 | −131.9 (2) |
C10—C12—C13—C14 | 176.1 (4) | N2—Ag1—N3—C4 | 5.6 (2) |
C9—C11—C13—C12 | 1.7 (6) | C12—C10—N4—C9 | 1.8 (6) |
C9—C11—C13—C14 | −175.0 (4) | C12—C10—N4—Ag1i | −177.7 (3) |
C12—C13—C14—N1 | 49.0 (5) | C11—C9—N4—C10 | −0.5 (6) |
C11—C13—C14—N1 | −134.4 (4) | C11—C9—N4—Ag1i | 178.9 (3) |
C2—C1—N1—N2 | −1.4 (4) | F2—C15—S1—O1 | −176.9 (5) |
C2—C1—N1—C14 | −172.0 (4) | F3—C15—S1—O1 | 59.0 (5) |
C13—C14—N1—N2 | 58.6 (4) | F1—C15—S1—O1 | −62.9 (5) |
C13—C14—N1—C1 | −131.5 (4) | F2—C15—S1—O3 | −55.9 (5) |
C2—C3—N2—N1 | −1.1 (4) | F3—C15—S1—O3 | 179.9 (4) |
C4—C3—N2—N1 | 179.4 (3) | F1—C15—S1—O3 | 58.1 (5) |
C2—C3—N2—Ag1 | −166.5 (2) | F2—C15—S1—O2 | 65.5 (5) |
C4—C3—N2—Ag1 | 14.0 (4) | F3—C15—S1—O2 | −58.7 (5) |
C1—N1—N2—C3 | 1.6 (4) | F1—C15—S1—O2 | 179.5 (5) |
C14—N1—N2—C3 | 173.1 (3) | | |
Symmetry code: (i) −x+1, −y+1, −z+2. |
Hydrogen-bond geometry (Å, º) top
D—H···A | D—H | H···A | D···A | D—H···A |
C2—H2···O1ii | 0.93 | 2.45 | 3.375 (6) | 171 |
C12—H12···F1iii | 0.93 | 2.45 | 3.326 (7) | 156 |
Symmetry codes: (ii) −x+1, −y+1, −z+1; (iii) x−1, y+1, z. |
Experimental details
Crystal data |
Chemical formula | [Ag2(C14H12N4)2](CF3SO3)2 |
Mr | 986.44 |
Crystal system, space group | Triclinic, P1 |
Temperature (K) | 293 |
a, b, c (Å) | 7.9430 (16), 8.5368 (17), 13.739 (3) |
α, β, γ (°) | 75.64 (3), 86.57 (3), 79.16 (3) |
V (Å3) | 886.3 (3) |
Z | 1 |
Radiation type | Mo Kα |
µ (mm−1) | 1.31 |
Crystal size (mm) | 0.30 × 0.28 × 0.25 |
|
Data collection |
Diffractometer | Bruker SMART CCD area-detector diffractometer |
Absorption correction | Multi-scan (SADABS; Sheldrick, 1996) |
Tmin, Tmax | 0.68, 0.72 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 4510, 3099, 2678 |
Rint | 0.018 |
(sin θ/λ)max (Å−1) | 0.595 |
|
Refinement |
R[F2 > 2σ(F2)], wR(F2), S | 0.036, 0.095, 1.07 |
No. of reflections | 3099 |
No. of parameters | 245 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.59, −0.53 |
Selected geometric parameters (Å, º) topAg1—N4i | 2.196 (3) | Ag1—N3 | 2.346 (3) |
Ag1—N2 | 2.307 (3) | | |
| | | |
N4i—Ag1—N2 | 136.04 (11) | N2—Ag1—N3 | 72.05 (11) |
N4i—Ag1—N3 | 133.89 (11) | | |
Symmetry code: (i) −x+1, −y+1, −z+2. |
Hydrogen-bond geometry (Å, º) top
D—H···A | D—H | H···A | D···A | D—H···A |
C2—H2···O1ii | 0.93 | 2.45 | 3.375 (6) | 171 |
C12—H12···F1iii | 0.93 | 2.45 | 3.326 (7) | 156 |
Symmetry codes: (ii) −x+1, −y+1, −z+1; (iii) x−1, y+1, z. |
The rational design and synthesis of functional coordination architectures has attracted much attention in recent years owing to their interesting structures and their potential uses as functional materials (Chen et al., 2006; Janiak, 2003; Robin & Fromm, 2006; Steel, 2005; Wang et al., 2008). Although the principles for controlling the solid structures of the target products still need to be classified and established, many rational synthetic strategies have been brought forward and have proved significant in the design of metal-based coordination complexes. The selection of suitable ligands as building blocks is undoubtedly a key point in manipulating the final structures of the complexes (Robin & Fromm, 2006; Steel, 2005). Other factors, such as the coordination geometry or radius of the metal ions (Du et al., 2007; Liu, Wang et al., 2007), the size or coordination ability of the counter-anions (Campos-Fernández et al., 2005; Hirsch et al., 1997; Huang et al., 2004; Xie et al., 2004; Zou et al., 2004), the presence of auxiliary ligands (Liu, Shi et al., 2006; Liu, Wang et al., 2007) or solvents (Kasai et al., 2000; Raehm et al., 2003), metal/ligand ratio (Saalfrank et al., 2001), and even pH value (Du et al., 2002), have also been found to influence significantly the structural topologies of such coordination frameworks.
Numerous related bis-heterocyclic chelating or bridging ligands have been synthesized and used extensively to construct functional coordination complexes that contain different hetero-aromatic ring systems, for example, pyridine, pyrazine, quinoline, quinoxaline, pyrazole, imidazole, thiazoles and their benzo-analogues (Steel, 2005). Ward and co-workers have reported many coordination architectures involving 3-(2-pyridyl)-1H-pyrazole and its derivative ligands (Bell et al., 2003; Paul et al., 2004; Singh et al., 2003; Ward et al., 2001). In our previous work, a series of 3-(2-pyridyl)pyrazole-based ligands have also been used to construct complexes with various structures, including multi-nuclear discrete molecules as well as one- and two-dimensional coordination polymers, which also exhibit interesting properties (Liu, Chen et al., 2006, Liu, Li et al., 2007; Liu, Shi et al., 2006; Liu, Zhang et al., 2007; Zhang et al., 2005; Zou et al., 2006). Recently, we have reported the preparation of a nonplanar flexible ligand based on a pyrazolyl–pyridine chelating unit and a pendant pyridyl group, 3-[3-(2-pyridyl)pyrazol-1-ylmethyl]pyridine (L) (Liu, Li et al., 2007). Its reaction with AgClO4 produced a one-dimensional helical chain coordination polymer, {[Ag(L)](ClO4)}∞, (II). To further investigate the influence of different counter-anions on the self-assembly process of coordination complexes, we chose to use L to construct new functional AgI complexes through its reaction with AgCF3SO3. We report here the crystal structure of complex (I), {[Ag(L)](CF3SO3)}2, and discuss the effect of different the counter-anions, ClO4- for (II) and CF3SO3- for (I), on the final structures of the relevant coordination complexes.
The structure of (I) consists of a centrosymmetric dinuclear [Ag(L)]22+ unit and two uncoordinated CF3SO3- ions. The dinuclear [Ag(L)]22+ cation (Fig. 1) comprises two L ligands and two AgI centers. Each AgI center adopts a distorted trigonal–planar geometry formed by three N-atom donors, two from the pyridyl–pyrazole ring system of one L ligand, and one from the pendant pyridine ring of another L ligand. All the Ag—N bond distances (Table 1) are in the normal range found in such complexes (Liu, Chen et al., 2006; Liu, Li et al., 2007). Meanwhile, each uncoordinated CF3SO3- anion exhibits a weak interaction with the AgI center [Ag1···O2 = 2.660 (5) Å]. In addition, adjacent discrete dinuclear [Ag(L)]22+ units are assembled into different one-dimensional chains, along the [001] and [110] directions, by the combined effects of intermolecular face-to-face π–π stacking [the centroid–centroid separation being 3.804 (5) Å between the pyridyl–pyrazole ring systems; symmetry code: -x + 1, -y + 1, -z + 3] (Janiak, 2000), C—H···X hydrogen-bonding interactions (X = O and F) (Desiraju & Steiner, 1999) and the weak Ag···O interactions mentioned above (Fig. 2). The net result is a two-dimensional network running parallel to the (110) plane (Fig. 3).
In general, the effect of counter-anions on the self-assembly process of coordination complexes can be explained as being due to differences in sizes, shapes and coordination ability (Campos-Fernández et al., 2005; Hirsch et al., 1997; Huang et al., 2004; Xie et al., 2004; Zou et al., 2004).
The structural differences of complexes (I) and (II) serve to exemplify the eventual influence of counter-anions on the construction of supramolecular frameworks. Even if neither the ClO4- anion in (II) nor the CF3SO3- anion in (I) coordinates to the AgI cation, owing to their size difference they fulfill quite different template roles, strongly affecting the building of the corresponding final frameworks through weak Ag···O interactions with the different cationic subunits [a dinuclear motif in complex (I) and a one-dimensional motif in complex (II); see the scheme below]. This analysis shows that changes in counter-anions could adjust the framework formation of such complexes, and this fact may provide an effective method for controlling the coordination architectures of compounds with potentially useful properties.