The title complex, [Ni
2Cl
4(C
22H
17N
3)
2], was synthesized solvothermally. The molecule is a centrosymmetric dimer with the unique Ni
II centre in a distorted octahedral N
3Cl
3 coordination environment. The chloride bridges are highly asymmetric. In the 4′-
p-tolyl-2,2′:6′,2′′-terpyridine ligand, the
p-tolyl group is perfectly coplanar with the attached pyridine ring, and this differs from the situation found in previously reported compounds; however, there are no π–π interactions between the ligands. The terminal Cl atom forms four intermolecular C—H

Cl hydrogen bonds with one methyl and three methine groups. The methyl group also forms intermolecular C—H

π interactions with a pyridine ring. These nonclassical hydrogen bonds extend the molecule into a three-dimensional network.
Supporting information
CCDC reference: 742223
4'-p-tolyl-2,2':6',2''-terpyridine (ttp) was prepared by an improved
Kröhnke condensation method (Wang et al., 2007; Collin et
al.,
1991). A mixture of NiCl2.6H2O (0.2 mmol, 0.0476 g), ttp (0.2 mmol,
0.0646 g) and EtOH (10 ml) was placed in a 23 ml of Teflon-lined stainless steel
vessel and heated under autogenous pressure at 412 K for 3 d, followed by
cooling to room temperature at a rate of 5 K h-1. Light-green block-shaped
crystals of (I) were obtained.
All H atoms were positioned geometrically and allowed to ride on their parent C
atoms, with C—H distances of 0.93 or 0.96Å and Uiso(H) = 1.2 or
1.5Ueq(C) for aromatic or methyl H atoms, respectively.
Data collection: APEX2 (Bruker, 2004); cell refinement: APEX2 (Bruker, 2004); data reduction: APEX2 (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).
Di-µ-chlorido-bis[chlorido(4'-
p-tolyl-2,2':6',2''-terpyridine-
κ3N,
N',
N'')nickel(II)]
top
Crystal data top
[Ni2Cl4(C22H17N3)2] | F(000) = 928 |
Mr = 905.99 | Dx = 1.558 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ybc | Cell parameters from 2108 reflections |
a = 14.2218 (11) Å | θ = 2.2–24.0° |
b = 12.7866 (10) Å | µ = 1.29 mm−1 |
c = 10.8659 (8) Å | T = 298 K |
β = 102.219 (1)° | Block, light green |
V = 1931.2 (3) Å3 | 0.45 × 0.35 × 0.20 mm |
Z = 2 | |
Data collection top
Bruker APEXII CCD area-detector diffractometer | 3965 independent reflections |
Radiation source: fine-focus sealed tube | 2507 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.055 |
ϕ and ω scans | θmax = 26.5°, θmin = 2.2° |
Absorption correction: multi-scan (SADABS; Bruker, 2002) | h = −17→17 |
Tmin = 0.594, Tmax = 0.782 | k = −15→15 |
10824 measured reflections | l = −13→12 |
Refinement top
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.037 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.079 | H-atom parameters constrained |
S = 0.86 | w = 1/[σ2(Fo2) + (0.026P)2 + 0.0718P] where P = (Fo2 + 2Fc2)/3 |
3965 reflections | (Δ/σ)max = 0.002 |
254 parameters | Δρmax = 0.35 e Å−3 |
0 restraints | Δρmin = −0.35 e Å−3 |
Crystal data top
[Ni2Cl4(C22H17N3)2] | V = 1931.2 (3) Å3 |
Mr = 905.99 | Z = 2 |
Monoclinic, P21/c | Mo Kα radiation |
a = 14.2218 (11) Å | µ = 1.29 mm−1 |
b = 12.7866 (10) Å | T = 298 K |
c = 10.8659 (8) Å | 0.45 × 0.35 × 0.20 mm |
β = 102.219 (1)° | |
Data collection top
Bruker APEXII CCD area-detector diffractometer | 3965 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 2002) | 2507 reflections with I > 2σ(I) |
Tmin = 0.594, Tmax = 0.782 | Rint = 0.055 |
10824 measured reflections | |
Refinement top
R[F2 > 2σ(F2)] = 0.037 | 0 restraints |
wR(F2) = 0.079 | H-atom parameters constrained |
S = 0.86 | Δρmax = 0.35 e Å−3 |
3965 reflections | Δρmin = −0.35 e Å−3 |
254 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 > 2sigma(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 | |
C1 | 0.07181 (19) | 0.7479 (2) | −0.0440 (3) | 0.0355 (7) | |
H1 | 0.0417 | 0.7191 | −0.1208 | 0.043* | |
C2 | 0.0659 (2) | 0.8539 (2) | −0.0281 (3) | 0.0408 (8) | |
H2 | 0.0335 | 0.8960 | −0.0932 | 0.049* | |
C3 | 0.1088 (2) | 0.8964 (2) | 0.0856 (3) | 0.0439 (8) | |
H3 | 0.1039 | 0.9678 | 0.0997 | 0.053* | |
C4 | 0.1595 (2) | 0.8324 (2) | 0.1792 (3) | 0.0394 (8) | |
H4 | 0.1900 | 0.8603 | 0.2564 | 0.047* | |
C5 | 0.16419 (19) | 0.7274 (2) | 0.1566 (2) | 0.0300 (7) | |
C6 | 0.21755 (19) | 0.6507 (2) | 0.2497 (2) | 0.0298 (7) | |
C7 | 0.27509 (19) | 0.6752 (2) | 0.3646 (2) | 0.0341 (7) | |
H7 | 0.2829 | 0.7446 | 0.3905 | 0.041* | |
C8 | 0.32195 (19) | 0.5953 (2) | 0.4426 (3) | 0.0331 (7) | |
C9 | 0.3070 (2) | 0.4931 (2) | 0.3983 (3) | 0.0374 (7) | |
H9 | 0.3367 | 0.4379 | 0.4473 | 0.045* | |
C10 | 0.24827 (19) | 0.4729 (2) | 0.2817 (2) | 0.0327 (7) | |
C11 | 0.2274 (2) | 0.3684 (2) | 0.2219 (3) | 0.0331 (7) | |
C12 | 0.2611 (2) | 0.2753 (2) | 0.2775 (3) | 0.0454 (8) | |
H12 | 0.2986 | 0.2748 | 0.3588 | 0.054* | |
C13 | 0.2392 (2) | 0.1825 (2) | 0.2128 (3) | 0.0534 (9) | |
H13 | 0.2602 | 0.1189 | 0.2503 | 0.064* | |
C14 | 0.1858 (2) | 0.1864 (2) | 0.0917 (3) | 0.0444 (8) | |
H14 | 0.1715 | 0.1255 | 0.0446 | 0.053* | |
C15 | 0.1537 (2) | 0.2817 (2) | 0.0413 (3) | 0.0387 (8) | |
H15 | 0.1176 | 0.2835 | −0.0407 | 0.046* | |
C16 | 0.3850 (2) | 0.6185 (2) | 0.5672 (3) | 0.0358 (7) | |
C17 | 0.3981 (2) | 0.7186 (3) | 0.6128 (3) | 0.0471 (9) | |
H17 | 0.3671 | 0.7733 | 0.5642 | 0.057* | |
C18 | 0.4563 (2) | 0.7404 (3) | 0.7290 (3) | 0.0515 (9) | |
H18 | 0.4634 | 0.8094 | 0.7565 | 0.062* | |
C19 | 0.5036 (2) | 0.6626 (3) | 0.8047 (3) | 0.0444 (8) | |
C20 | 0.4915 (3) | 0.5631 (3) | 0.7588 (3) | 0.0762 (13) | |
H20 | 0.5228 | 0.5086 | 0.8075 | 0.091* | |
C21 | 0.4346 (3) | 0.5408 (3) | 0.6432 (3) | 0.0716 (12) | |
H21 | 0.4293 | 0.4719 | 0.6151 | 0.086* | |
C22 | 0.5653 (2) | 0.6861 (3) | 0.9325 (3) | 0.0619 (11) | |
H22A | 0.5299 | 0.6708 | 0.9964 | 0.093* | |
H22B | 0.5830 | 0.7586 | 0.9368 | 0.093* | |
H22C | 0.6223 | 0.6437 | 0.9457 | 0.093* | |
Cl1 | 0.01801 (5) | 0.48582 (6) | −0.14767 (6) | 0.03777 (19) | |
Cl2 | 0.27195 (5) | 0.53471 (6) | −0.04602 (7) | 0.0417 (2) | |
N1 | 0.11883 (15) | 0.68401 (17) | 0.0457 (2) | 0.0309 (6) | |
N2 | 0.20567 (15) | 0.55174 (17) | 0.2100 (2) | 0.0300 (6) | |
N3 | 0.17180 (16) | 0.37204 (17) | 0.1039 (2) | 0.0320 (6) | |
Ni1 | 0.12991 (3) | 0.52225 (3) | 0.03903 (3) | 0.03153 (12) | |
Atomic displacement parameters (Å2) top | U11 | U22 | U33 | U12 | U13 | U23 |
C1 | 0.0392 (18) | 0.0359 (19) | 0.0292 (17) | 0.0040 (15) | 0.0027 (14) | 0.0053 (13) |
C2 | 0.0475 (19) | 0.0354 (19) | 0.0374 (19) | 0.0096 (16) | 0.0039 (15) | 0.0106 (14) |
C3 | 0.056 (2) | 0.0237 (18) | 0.051 (2) | 0.0053 (16) | 0.0091 (17) | 0.0004 (15) |
C4 | 0.053 (2) | 0.0295 (18) | 0.0333 (17) | 0.0021 (15) | 0.0027 (15) | −0.0016 (14) |
C5 | 0.0340 (16) | 0.0289 (18) | 0.0251 (16) | 0.0005 (13) | 0.0019 (13) | 0.0001 (12) |
C6 | 0.0338 (16) | 0.0274 (17) | 0.0256 (16) | 0.0006 (13) | 0.0003 (13) | −0.0003 (12) |
C7 | 0.0405 (17) | 0.0280 (17) | 0.0307 (17) | 0.0000 (14) | 0.0006 (14) | −0.0027 (13) |
C8 | 0.0330 (16) | 0.0372 (19) | 0.0267 (16) | −0.0007 (14) | 0.0008 (13) | 0.0003 (13) |
C9 | 0.0421 (18) | 0.0345 (19) | 0.0303 (16) | 0.0027 (14) | −0.0046 (14) | 0.0059 (13) |
C10 | 0.0376 (17) | 0.0286 (17) | 0.0285 (16) | 0.0002 (14) | −0.0007 (13) | 0.0026 (13) |
C11 | 0.0384 (17) | 0.0305 (18) | 0.0282 (16) | 0.0033 (14) | 0.0022 (14) | 0.0034 (13) |
C12 | 0.059 (2) | 0.035 (2) | 0.0355 (19) | 0.0059 (17) | −0.0051 (16) | 0.0056 (15) |
C13 | 0.074 (2) | 0.0255 (19) | 0.058 (2) | 0.0062 (18) | 0.0069 (19) | 0.0088 (16) |
C14 | 0.057 (2) | 0.0245 (18) | 0.050 (2) | −0.0037 (16) | 0.0089 (17) | −0.0029 (15) |
C15 | 0.0423 (18) | 0.035 (2) | 0.0362 (18) | −0.0045 (15) | 0.0035 (15) | −0.0033 (15) |
C16 | 0.0350 (17) | 0.042 (2) | 0.0265 (16) | 0.0023 (15) | −0.0025 (13) | −0.0011 (14) |
C17 | 0.051 (2) | 0.043 (2) | 0.0379 (19) | 0.0033 (17) | −0.0114 (16) | −0.0023 (16) |
C18 | 0.052 (2) | 0.048 (2) | 0.044 (2) | 0.0021 (17) | −0.0116 (17) | −0.0127 (17) |
C19 | 0.0383 (18) | 0.058 (2) | 0.0324 (18) | 0.0050 (17) | −0.0040 (14) | −0.0068 (16) |
C20 | 0.105 (3) | 0.056 (3) | 0.046 (2) | 0.020 (2) | −0.034 (2) | −0.0017 (19) |
C21 | 0.102 (3) | 0.043 (2) | 0.049 (2) | 0.013 (2) | −0.031 (2) | −0.0095 (18) |
C22 | 0.058 (2) | 0.075 (3) | 0.042 (2) | 0.013 (2) | −0.0134 (17) | −0.0151 (19) |
Cl1 | 0.0417 (4) | 0.0421 (5) | 0.0254 (4) | −0.0043 (4) | −0.0021 (3) | −0.0028 (3) |
Cl2 | 0.0446 (5) | 0.0389 (5) | 0.0404 (4) | 0.0037 (4) | 0.0061 (4) | 0.0055 (4) |
N1 | 0.0339 (13) | 0.0275 (14) | 0.0281 (13) | 0.0007 (11) | −0.0008 (11) | 0.0014 (11) |
N2 | 0.0344 (13) | 0.0253 (14) | 0.0270 (13) | −0.0006 (11) | −0.0011 (11) | 0.0003 (10) |
N3 | 0.0371 (14) | 0.0264 (14) | 0.0293 (14) | 0.0003 (11) | −0.0005 (11) | −0.0001 (10) |
Ni1 | 0.0386 (2) | 0.0250 (2) | 0.0260 (2) | 0.00044 (18) | −0.00440 (16) | 0.00014 (16) |
Geometric parameters (Å, º) top
C1—N1 | 1.338 (3) | C13—H13 | 0.9300 |
C1—C2 | 1.371 (4) | C14—C15 | 1.374 (4) |
C1—H1 | 0.9300 | C14—H14 | 0.9300 |
C2—C3 | 1.369 (4) | C15—N3 | 1.338 (3) |
C2—H2 | 0.9300 | C15—H15 | 0.9300 |
C3—C4 | 1.384 (4) | C16—C17 | 1.371 (4) |
C3—H3 | 0.9300 | C16—C21 | 1.385 (4) |
C4—C5 | 1.368 (4) | C17—C18 | 1.384 (4) |
C4—H4 | 0.9300 | C17—H17 | 0.9300 |
C5—N1 | 1.359 (3) | C18—C19 | 1.373 (4) |
C5—C6 | 1.496 (4) | C18—H18 | 0.9300 |
C6—N2 | 1.336 (3) | C19—C20 | 1.363 (4) |
C6—C7 | 1.376 (3) | C19—C22 | 1.507 (4) |
C7—C8 | 1.403 (4) | C20—C21 | 1.373 (4) |
C7—H7 | 0.9300 | C20—H20 | 0.9300 |
C8—C9 | 1.393 (4) | C21—H21 | 0.9300 |
C8—C16 | 1.487 (4) | C22—H22A | 0.9600 |
C9—C10 | 1.386 (4) | C22—H22B | 0.9600 |
C9—H9 | 0.9300 | C22—H22C | 0.9600 |
C10—N2 | 1.338 (3) | Cl1—Ni1 | 2.3449 (7) |
C10—C11 | 1.489 (4) | Cl1—Ni1i | 2.6231 (8) |
C11—N3 | 1.357 (3) | Cl2—Ni1 | 2.3980 (8) |
C11—C12 | 1.375 (4) | N1—Ni1 | 2.077 (2) |
C12—C13 | 1.380 (4) | N2—Ni1 | 1.976 (2) |
C12—H12 | 0.9300 | N3—Ni1 | 2.089 (2) |
C13—C14 | 1.374 (4) | Ni1—Cl1i | 2.6231 (8) |
| | | |
N1—C1—C2 | 123.1 (3) | C21—C16—C8 | 122.2 (3) |
N1—C1—H1 | 118.4 | C16—C17—C18 | 121.8 (3) |
C2—C1—H1 | 118.4 | C16—C17—H17 | 119.1 |
C3—C2—C1 | 118.6 (3) | C18—C17—H17 | 119.1 |
C3—C2—H2 | 120.7 | C19—C18—C17 | 121.5 (3) |
C1—C2—H2 | 120.7 | C19—C18—H18 | 119.2 |
C2—C3—C4 | 119.4 (3) | C17—C18—H18 | 119.2 |
C2—C3—H3 | 120.3 | C20—C19—C18 | 116.7 (3) |
C4—C3—H3 | 120.3 | C20—C19—C22 | 121.8 (3) |
C5—C4—C3 | 119.0 (3) | C18—C19—C22 | 121.5 (3) |
C5—C4—H4 | 120.5 | C19—C20—C21 | 122.2 (3) |
C3—C4—H4 | 120.5 | C19—C20—H20 | 118.9 |
N1—C5—C4 | 121.9 (3) | C21—C20—H20 | 118.9 |
N1—C5—C6 | 114.2 (2) | C20—C21—C16 | 121.5 (3) |
C4—C5—C6 | 124.0 (2) | C20—C21—H21 | 119.2 |
N2—C6—C7 | 121.2 (3) | C16—C21—H21 | 119.2 |
N2—C6—C5 | 113.1 (2) | C19—C22—H22A | 109.5 |
C7—C6—C5 | 125.7 (3) | C19—C22—H22B | 109.5 |
C6—C7—C8 | 119.9 (3) | H22A—C22—H22B | 109.5 |
C6—C7—H7 | 120.1 | C19—C22—H22C | 109.5 |
C8—C7—H7 | 120.1 | H22A—C22—H22C | 109.5 |
C9—C8—C7 | 117.1 (3) | H22B—C22—H22C | 109.5 |
C9—C8—C16 | 121.4 (3) | Ni1—Cl1—Ni1i | 94.62 (3) |
C7—C8—C16 | 121.5 (3) | C1—N1—C5 | 117.8 (2) |
C10—C9—C8 | 120.6 (3) | C1—N1—Ni1 | 127.78 (19) |
C10—C9—H9 | 119.7 | C5—N1—Ni1 | 114.37 (18) |
C8—C9—H9 | 119.7 | C6—N2—C10 | 121.0 (2) |
N2—C10—C9 | 120.2 (3) | C6—N2—Ni1 | 119.39 (18) |
N2—C10—C11 | 113.5 (2) | C10—N2—Ni1 | 119.56 (19) |
C9—C10—C11 | 126.3 (3) | C15—N3—C11 | 117.5 (2) |
N3—C11—C12 | 121.6 (3) | C15—N3—Ni1 | 127.71 (19) |
N3—C11—C10 | 113.8 (2) | C11—N3—Ni1 | 114.71 (18) |
C12—C11—C10 | 124.5 (3) | N2—Ni1—N1 | 78.89 (9) |
C11—C12—C13 | 120.0 (3) | N2—Ni1—N3 | 78.37 (9) |
C11—C12—H12 | 120.0 | N1—Ni1—N3 | 157.26 (9) |
C13—C12—H12 | 120.0 | N2—Ni1—Cl1 | 170.45 (7) |
C14—C13—C12 | 118.4 (3) | N1—Ni1—Cl1 | 100.69 (6) |
C14—C13—H13 | 120.8 | N3—Ni1—Cl1 | 101.67 (6) |
C12—C13—H13 | 120.8 | N2—Ni1—Cl2 | 90.77 (7) |
C15—C14—C13 | 118.9 (3) | N1—Ni1—Cl2 | 91.36 (6) |
C15—C14—H14 | 120.5 | N3—Ni1—Cl2 | 89.31 (6) |
C13—C14—H14 | 120.5 | Cl1—Ni1—Cl2 | 98.78 (3) |
N3—C15—C14 | 123.4 (3) | N2—Ni1—Cl1i | 85.07 (7) |
N3—C15—H15 | 118.3 | N1—Ni1—Cl1i | 87.10 (6) |
C14—C15—H15 | 118.3 | N3—Ni1—Cl1i | 90.60 (6) |
C17—C16—C21 | 116.2 (3) | Cl1—Ni1—Cl1i | 85.38 (3) |
C17—C16—C8 | 121.7 (3) | Cl2—Ni1—Cl1i | 175.77 (3) |
| | | |
N1—C1—C2—C3 | −1.1 (5) | C7—C6—N2—C10 | 1.0 (4) |
C1—C2—C3—C4 | 2.3 (5) | C5—C6—N2—C10 | −179.9 (2) |
C2—C3—C4—C5 | −1.1 (5) | C7—C6—N2—Ni1 | −175.6 (2) |
C3—C4—C5—N1 | −1.3 (4) | C5—C6—N2—Ni1 | 3.5 (3) |
C3—C4—C5—C6 | 179.3 (3) | C9—C10—N2—C6 | −1.0 (4) |
N1—C5—C6—N2 | −4.2 (4) | C11—C10—N2—C6 | −179.7 (2) |
C4—C5—C6—N2 | 175.2 (3) | C9—C10—N2—Ni1 | 175.6 (2) |
N1—C5—C6—C7 | 174.8 (3) | C11—C10—N2—Ni1 | −3.1 (3) |
C4—C5—C6—C7 | −5.8 (5) | C14—C15—N3—C11 | 2.2 (4) |
N2—C6—C7—C8 | −0.5 (4) | C14—C15—N3—Ni1 | 179.0 (2) |
C5—C6—C7—C8 | −179.4 (3) | C12—C11—N3—C15 | −2.5 (4) |
C6—C7—C8—C9 | −0.1 (4) | C10—C11—N3—C15 | 176.7 (2) |
C6—C7—C8—C16 | 179.8 (3) | C12—C11—N3—Ni1 | −179.7 (2) |
C7—C8—C9—C10 | 0.1 (4) | C10—C11—N3—Ni1 | −0.5 (3) |
C16—C8—C9—C10 | −179.8 (3) | C6—N2—Ni1—N1 | −1.5 (2) |
C8—C9—C10—N2 | 0.4 (4) | C10—N2—Ni1—N1 | −178.2 (2) |
C8—C9—C10—C11 | 178.9 (3) | C6—N2—Ni1—N3 | 178.8 (2) |
N2—C10—C11—N3 | 2.2 (4) | C10—N2—Ni1—N3 | 2.2 (2) |
C9—C10—C11—N3 | −176.3 (3) | C6—N2—Ni1—Cl2 | 89.7 (2) |
N2—C10—C11—C12 | −178.6 (3) | C10—N2—Ni1—Cl2 | −86.9 (2) |
C9—C10—C11—C12 | 2.8 (5) | C6—N2—Ni1—Cl1i | −89.5 (2) |
N3—C11—C12—C13 | 0.6 (5) | C10—N2—Ni1—Cl1i | 93.8 (2) |
C10—C11—C12—C13 | −178.5 (3) | C1—N1—Ni1—N2 | −179.8 (2) |
C11—C12—C13—C14 | 1.7 (5) | C5—N1—Ni1—N2 | −1.00 (19) |
C12—C13—C14—C15 | −2.0 (5) | C1—N1—Ni1—N3 | −178.9 (2) |
C13—C14—C15—N3 | 0.0 (5) | C5—N1—Ni1—N3 | −0.1 (3) |
C9—C8—C16—C17 | −178.4 (3) | C1—N1—Ni1—Cl1 | −9.5 (2) |
C7—C8—C16—C17 | 1.7 (5) | C5—N1—Ni1—Cl1 | 169.28 (18) |
C9—C8—C16—C21 | 2.4 (5) | C1—N1—Ni1—Cl2 | 89.7 (2) |
C7—C8—C16—C21 | −177.5 (3) | C5—N1—Ni1—Cl2 | −91.52 (18) |
C21—C16—C17—C18 | −1.2 (5) | C1—N1—Ni1—Cl1i | −94.2 (2) |
C8—C16—C17—C18 | 179.6 (3) | C5—N1—Ni1—Cl1i | 84.54 (18) |
C16—C17—C18—C19 | −0.1 (5) | C15—N3—Ni1—N2 | −177.7 (3) |
C17—C18—C19—C20 | 0.9 (5) | C11—N3—Ni1—N2 | −0.8 (2) |
C17—C18—C19—C22 | −178.7 (3) | C15—N3—Ni1—N1 | −178.6 (2) |
C18—C19—C20—C21 | −0.3 (6) | C11—N3—Ni1—N1 | −1.7 (4) |
C22—C19—C20—C21 | 179.3 (4) | C15—N3—Ni1—Cl1 | 12.1 (2) |
C19—C20—C21—C16 | −1.0 (7) | C11—N3—Ni1—Cl1 | −171.07 (18) |
C17—C16—C21—C20 | 1.7 (6) | C15—N3—Ni1—Cl2 | −86.8 (2) |
C8—C16—C21—C20 | −179.0 (3) | C11—N3—Ni1—Cl2 | 90.11 (19) |
C2—C1—N1—C5 | −1.3 (4) | C15—N3—Ni1—Cl1i | 97.5 (2) |
C2—C1—N1—Ni1 | 177.4 (2) | C11—N3—Ni1—Cl1i | −85.66 (19) |
C4—C5—N1—C1 | 2.6 (4) | Ni1i—Cl1—Ni1—N1 | −86.16 (6) |
C6—C5—N1—C1 | −178.1 (2) | Ni1i—Cl1—Ni1—N3 | 89.66 (7) |
C4—C5—N1—Ni1 | −176.4 (2) | Ni1i—Cl1—Ni1—Cl2 | −179.23 (3) |
C6—C5—N1—Ni1 | 3.0 (3) | Ni1i—Cl1—Ni1—Cl1i | 0.0 |
Symmetry code: (i) −x, −y+1, −z. |
Hydrogen-bond geometry (Å, º) top
D—H···A | D—H | H···A | D···A | D—H···A |
C4—H4···Cl2ii | 0.93 | 2.59 | 3.512 (3) | 171 |
C7—H7···Cl2ii | 0.93 | 2.91 | 3.837 (2) | 170 |
C17—H17···Cl2ii | 0.93 | 2.93 | 3.851 (3) | 170 |
C22—H22C···Cl2iii | 0.96 | 2.82 | 3.693 (3) | 151 |
Symmetry codes: (ii) x, −y+3/2, z+1/2; (iii) −x+1, −y+1, −z+1. |
Experimental details
Crystal data |
Chemical formula | [Ni2Cl4(C22H17N3)2] |
Mr | 905.99 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 298 |
a, b, c (Å) | 14.2218 (11), 12.7866 (10), 10.8659 (8) |
β (°) | 102.219 (1) |
V (Å3) | 1931.2 (3) |
Z | 2 |
Radiation type | Mo Kα |
µ (mm−1) | 1.29 |
Crystal size (mm) | 0.45 × 0.35 × 0.20 |
|
Data collection |
Diffractometer | Bruker APEXII CCD area-detector diffractometer |
Absorption correction | Multi-scan (SADABS; Bruker, 2002) |
Tmin, Tmax | 0.594, 0.782 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 10824, 3965, 2507 |
Rint | 0.055 |
(sin θ/λ)max (Å−1) | 0.628 |
|
Refinement |
R[F2 > 2σ(F2)], wR(F2), S | 0.037, 0.079, 0.86 |
No. of reflections | 3965 |
No. of parameters | 254 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.35, −0.35 |
Selected geometric parameters (Å, º) topCl1—Ni1 | 2.3449 (7) | N2—Ni1 | 1.976 (2) |
Cl2—Ni1 | 2.3980 (8) | N3—Ni1 | 2.089 (2) |
N1—Ni1 | 2.077 (2) | Ni1—Cl1i | 2.6231 (8) |
| | | |
N2—Ni1—N1 | 78.89 (9) | N3—Ni1—Cl2 | 89.31 (6) |
N2—Ni1—N3 | 78.37 (9) | Cl1—Ni1—Cl2 | 98.78 (3) |
N1—Ni1—N3 | 157.26 (9) | N2—Ni1—Cl1i | 85.07 (7) |
N2—Ni1—Cl1 | 170.45 (7) | N1—Ni1—Cl1i | 87.10 (6) |
N1—Ni1—Cl1 | 100.69 (6) | N3—Ni1—Cl1i | 90.60 (6) |
N3—Ni1—Cl1 | 101.67 (6) | Cl1—Ni1—Cl1i | 85.38 (3) |
N2—Ni1—Cl2 | 90.77 (7) | Cl2—Ni1—Cl1i | 175.77 (3) |
N1—Ni1—Cl2 | 91.36 (6) | | |
Symmetry code: (i) −x, −y+1, −z. |
Hydrogen-bond geometry (Å, º) top
D—H···A | D—H | H···A | D···A | D—H···A |
C4—H4···Cl2ii | 0.93 | 2.59 | 3.512 (3) | 171 |
C7—H7···Cl2ii | 0.93 | 2.91 | 3.837 (2) | 170 |
C17—H17···Cl2ii | 0.93 | 2.93 | 3.851 (3) | 170 |
C22—H22C···Cl2iii | 0.96 | 2.82 | 3.693 (3) | 151 |
Symmetry codes: (ii) x, −y+3/2, z+1/2; (iii) −x+1, −y+1, −z+1. |
2,2':6',2''-Terpyridine and its derivatives are well known multidentate ligands. Among this ligand family, 4'-p-tolyl-2,2':6',2''-terpyridine (ttp) plays an important role because it is quite easy to prepare and derivatize via bromination and oxidation, and the electron-donor nature of the terminal methyl group is useful in certain cases. Hence, a number of transition metal (M) complexes of ttp have been studied for a variety of interesting properties, such as photophysics (Yoshikawa et al., 2007; Abrahamsson et al., 2005), photochemistry (Beley et al., 1991; Wilkinson et al., 2004), electrochemistry (Al-Noaimi et al., 2004; Chamchoumis & Potvin, 1999; Barigelletti et al., 2000; Collin et al., 1997; Mikel & Potvin, 2001), magnetism (Duboc et al., 2006; Yu et al., 2007), DNA binding (Uma et al., 2005; Jain et al., 2008; Bertrand et al., 2007; Jiang et al., 2008) and supramolecular assembly (Zhou et al., 2007; Liu et al., 2007; Messina et al., 2001; Yutaka et al., 2005; Hartshorn & Zibaseresht, 2006; Bray et al., 2008; Yucesan et al., 2005). All the complexes exist in the form of mononuclear [M(ttp)2]n+, except for the dinuclear manganese complex [Mn2(µ1,1-N3)2(N3)2(ttp)2] (Yu et al., 2007). Many metalloenzymes, including nickel enzymes, employ a dinuclear active site (Halcrow & Christou, 1994; Holm et al., 1996; Solomon et al., 1996; Wilcox, 1996). Lack of one Ni atom in the dinuclear active site can cause a reduction in catalytic activity or even complete inactivation of the enzyme. Halide-bridged dinuclear nickel complexes with nitrogen- and oxygen-containing ligands are occasionally utilized in ethylene oligomerization catalysis (Zhang et al., 2007; Sun et al., 2007). We present here the first structure of a dinuclear nickel(II) complex constructed with ttp and chloride ligands, namely di-µ-chlorido-bis{chlorido[4'-p-tolyl-2,2':6',2''-terpyridine-κ3N,N',N'']nickel(II)}, (I).
Complex (I) was obtained via a solvothermal reaction, but no solvent molecule could be detected within the cell. The molecule is arranged around an inversion center with a planar Ni2(µ-Cl)2 diamond-like framework (Fig. 1). The intramolecular Ni···Ni interatomic distance of 3.6565 (6)Å is typical of binuclear nickel(II) complexes and virtually excludes any specific interaction between these atoms. The coordination sphere of the NiII centre can be interpreted as a distorted octahedron (Table 1), with terpyridine atoms N1, N2 and N3 and the bridging atom Cl1 in the equatorial plane and the other bridging atom Cl1 and the terminal atom Cl2 in axial positions. The tridentate chelation results in the three pyridine rings in ttp being nearly coplanar, with the angles between the two outer pyridine rings and the central pyridine ring being as small as 5.68 (14) or 4.24 (14)°, which is common for ttp complexes. Compared to other ttp complexes, it is very unusal that the substituent tolyl group is almost in the same plane as the central pyridine ring, the torsion angles C7—C8—C16—C17 and C9—C8—C16—C21 are 1.8 (5) and 2.3 (5)°, respectively. The corresponding angles in previously reported compounds involving ttp ligand are significantly larger and only a few are less than 10° [cf 4.58, 6.94 and 9.46° in Yucesan et al. (2005), and 9.39° in Mikel & Potvin, (2001)].
Of the two bridging Cl1 atoms around an NiII center, that trans to the central ttp pyridine ring is much closer than that which is trans to the terminal Cl2 atom [2.3448 (7) versus 2.6232 (9)Å]. This reflects the difference of trans influence between pyridine and chloride, which are π-acid and π-donor ligand in nature, respectively. A similar difference in Ni—Cl distances is also present in other Ni2(µ-Cl)2Cl2 complexes with the Ni atom hexacoordinated and a pyridine ring opposite one of the two bridging Cl atoms [the two examples to date are: 2.367 versus 2.531Å (Constable et al., 2002) and 2.356 versus 2.520Å (Zhang et al., 2007)], but the difference in Ni—Cl distances found in (I) is certainly the largest. The good conjugation of all the rings in ttp mentioned above might be the reason. However, although ttp is a good extended π-system, there is no π–π stacking in (I) between the ttp planes in the crystal lattice. Instead, some nonclassical intermolecular hydrogen bonds as secondary interactions play a crucial role in self-assembling the molecules into a three-dimensional network, as discussed below.
As shown in Table 2 and the packing view (Fig. 2), the terminal Cl2 atom acts as an acceptor of four intermolecular C—H···Cl interactions with three aromatic CH groups from the same neighboring molecule and one methyl group from another adjacent molecule. One of the H···Cl distances is quite short at 2.59Å, suggesting a significant hydrogen bonding interaction, while the remaining three H···Cl distances fall slightly below the sum of van der Waals radii (2.95Å) and the C—H···Cl angles are fairly linear, consistent with criteria for C—H···Cl interactions (Aakeröy et al., 1999; Freytag et al., 2000). Atoms H4, H7 and H17 from the same ttp ligand surround atom Cl2 in a manner reminiscent of chelation. The Ni—Cl coordination bond provides both charge assistance and directionality for strengthening the C—H···Cl interactions. The four Ni—Cl···H angles are in the range 94–105°, compatible with other C—H···Cl cases assisted by terminal M—Cl bonds (Balamurugan et al., 2004).