organic compounds
4-[4-(Methylsulfanyl)phenyl]-6-phenyl-2,2′-bipyridine
aChemistry Department, University of Canterbury, PO Box 4800, Christchurch, New Zealand, and bDipartimento de Chimica, Università degli Studi di Ferrara, Ferrara 44100, Italy
*Correspondence e-mail: matthew.polson@canterbury.ac.nz
The structure of the title compound, C23H18N2S, is revealed by X-ray diffraction to be almost planar over all four aromatic rings; the pendant rings are at angles of 10.18, 14.12 and 15.42° relative to the central pyridine ring for the 4-methylsulfanyl, 2-pyridyl and 6-phenyl rings, respectively. The 2,6-aromatic substituents are disordered over two sites in a 0.6:0.4 occupancy ratio.
Experimental
Crystal data
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Data collection: APEX2 (Bruker, 2007); cell SAINT (Bruker, 2007); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1990); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEP-3 for Windows (Version 1.08; Farrugia, 1997); software used to prepare material for publication: publCIF (Westrip, 2008).
Supporting information
https://doi.org/10.1107/S1600536807065701/ww2105sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536807065701/ww2105Isup2.hkl
To a solution of 4-(methylsulfanyl)benzaldehyde (5 g), acetophenone (4.5 g), methanol (300 ml) and ammonia (0.81 g/ml, 50 ml) was added a sodium hydroxide solution (1.5 g in 50 ml water) with stirring. Overnight a precipitate of the condensation product formed. This was filtered, air dried and was used in the next step without further purification. This compound (5 g) was ground in a mortar and pestle with 2-acetylpyridine (2.5 g) and sodium hydroxide (0.83 g) until the mixture became a solid again. Excess ammonium hydroxide was added and the mixture dissolved in glacial acetic acid (50 ml) and was refluxed with stirring for 4 h. On cooling, the solution was poured into water (200 ml) and extracted with dichloromethane (3 x 50 ml). δ 2.54 (3H, s, CH3S), 7.35 (1H, ddd, py5'), 7.37 (2H, d, thio-ph3,5), 7.46 (1H, t, ph4), 7.53 (2H, dd, thio-ph2,6), 7.77 (2H, d, ph3,5), 7.87 (1H, td, py4'), 7.95 (1H, d, py5), 8.20 (2H, d, ph2,6), 8.63 (1H, d, py3), 8.68 (1H, d, py3'), 8.72 (1H, dd, py6'); 13C NMR (CDCl3): δ 15.5, 117.1, 118.1, 121.6, 123.9, 126.5, 127.1, 127.5, 128.7, 129.1, 135.0, 137.1, 139.4, 140.1, 148.8, 149.5, 156.0, 156.2, 157.2.
on silica gel with dichloromethane/methanol (95:5) yielded the pure product (1). Single crystals suitable for X-ray diffraction formed on slow evaporation from dichloromethane solution. Yield = 2.3 g (25%). Spectroscopic data: 1H NMR (CDCl3):The 2-pyridine and 6-phenyl rings are disordered in a 60/40 ratio over the two possible positions. The pyridine ring however always adopts a s-trans arrangement to the central pyridine nitrogen, presumably to minimize hydrogen/hydrogen repulsions.
The use of Self Assemblied Monolayers (SAMs) in the fabrication of molecular devices is a rapidly expanding field. To incorporate the useful photophysical properties of iridium complexes into a SAM, ligands must be capable of attaching to a surface. The compound (1), a bipyridine based ligand, includes a protected thiol group for attachment to a gold surface and a phenyl group for cyclometallation. Typically bipyridine ligands crystallize with the pyridine N atoms in a s-trans arrangement (Fitchett et al., 2005). This is attributed to reduction of C—H/H—C interactions. Here, the pyridine ring and the phenyl ring crystallize in identical conformations, leading to disorder. If C—H/H—C interactions were the dominant force for the arrangement of the ring, one would expect the phenyl ring to adopt a different arrangement due to the additional interaction. This implies that the dominant force for the arrangement of the rings is the attractive C—H/N interaction.
For related literature, see: Fitchett et al. (2005).
Data collection: APEX2 (Bruker, 2007); cell
SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 1990); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEP-3 for Windows (Version 1.08; Farrugia, 1997); software used to prepare material for publication: publCIF (Westrip, 2008).Fig. 1. The molecular structure of (1), showing displacement ellipsoids at the 50% probability level. |
C23H18N2S | F(000) = 744 |
Mr = 354.45 | Dx = 1.341 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ybc | Cell parameters from 1819 reflections |
a = 19.189 (3) Å | θ = 2.7–25.9° |
b = 5.3617 (8) Å | µ = 0.19 mm−1 |
c = 17.084 (3) Å | T = 93 K |
β = 92.262 (9)° | Plate, yellow |
V = 1756.3 (5) Å3 | 0.45 × 0.17 × 0.04 mm |
Z = 4 |
Bruker APEXII CCD area-detector diffractometer | 3118 independent reflections |
Radiation source: sealed tube | 1442 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.121 |
φ and ω scans | θmax = 25.1°, θmin = 2.4° |
Absorption correction: multi-scan (SADABS; Bruker, 2007) | h = −22→22 |
Tmin = 0.599, Tmax = 0.992 | k = −6→6 |
19871 measured reflections | l = −20→20 |
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)] = 0.063 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.161 | H-atom parameters constrained |
S = 0.93 | w = 1/[σ2(Fo2) + (0.0562P)2 + 0.5007P] where P = (Fo2 + 2Fc2)/3 |
3118 reflections | (Δ/σ)max < 0.001 |
236 parameters | Δρmax = 0.50 e Å−3 |
0 restraints | Δρmin = −0.35 e Å−3 |
C23H18N2S | V = 1756.3 (5) Å3 |
Mr = 354.45 | Z = 4 |
Monoclinic, P21/c | Mo Kα radiation |
a = 19.189 (3) Å | µ = 0.19 mm−1 |
b = 5.3617 (8) Å | T = 93 K |
c = 17.084 (3) Å | 0.45 × 0.17 × 0.04 mm |
β = 92.262 (9)° |
Bruker APEXII CCD area-detector diffractometer | 3118 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 2007) | 1442 reflections with I > 2σ(I) |
Tmin = 0.599, Tmax = 0.992 | Rint = 0.121 |
19871 measured reflections |
R[F2 > 2σ(F2)] = 0.063 | 0 restraints |
wR(F2) = 0.161 | H-atom parameters constrained |
S = 0.93 | Δρmax = 0.50 e Å−3 |
3118 reflections | Δρmin = −0.35 e Å−3 |
236 parameters |
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. |
x | y | z | Uiso*/Ueq | Occ. (<1) | |
C10 | 0.7765 (2) | 0.5910 (7) | 0.4911 (2) | 0.0262 (10) | |
C11 | 0.8384 (2) | 0.6255 (8) | 0.5330 (3) | 0.0467 (13) | |
H11 | 0.8788 | 0.5333 | 0.5204 | 0.056* | |
C12 | 0.8411 (2) | 0.7978 (9) | 0.5941 (3) | 0.0575 (15) | |
H12 | 0.8832 | 0.8205 | 0.6245 | 0.069* | |
C13 | 0.7843 (2) | 0.9318 (8) | 0.6101 (2) | 0.0383 (11) | |
H13 | 0.7862 | 1.0516 | 0.6511 | 0.046* | |
C14 | 0.7242 (2) | 0.8947 (9) | 0.5672 (3) | 0.0440 (12) | |
H14 | 0.6839 | 0.9883 | 0.5792 | 0.053* | |
N15 | 0.71985 (18) | 0.7258 (8) | 0.5069 (2) | 0.0428 (10) | 0.60 |
C15 | 0.71985 (18) | 0.7258 (8) | 0.5069 (2) | 0.0428 (10) | 0.40 |
H15 | 0.6775 | 0.7046 | 0.4769 | 0.051* | 0.40 |
N20 | 0.82507 (15) | 0.2544 (7) | 0.41731 (17) | 0.0296 (8) | |
C20 | 0.7730 (2) | 0.4149 (8) | 0.4222 (2) | 0.0278 (10) | |
C21 | 0.7176 (2) | 0.4300 (8) | 0.3674 (2) | 0.0300 (10) | |
H21 | 0.6811 | 0.5471 | 0.3741 | 0.036* | |
C22 | 0.71595 (19) | 0.2711 (8) | 0.3022 (2) | 0.0269 (9) | |
C23 | 0.7708 (2) | 0.1064 (8) | 0.2974 (2) | 0.0322 (11) | |
H23 | 0.7720 | −0.0040 | 0.2540 | 0.039* | |
C24 | 0.8246 (2) | 0.0983 (8) | 0.3549 (2) | 0.0314 (10) | |
C30 | 0.8832 (2) | −0.0776 (8) | 0.3508 (2) | 0.0306 (10) | |
C31 | 0.9434 (2) | −0.0504 (9) | 0.3971 (3) | 0.0453 (13) | |
H31 | 0.9469 | 0.0856 | 0.4327 | 0.054* | |
C32 | 0.9981 (3) | −0.2125 (10) | 0.3934 (3) | 0.0545 (14) | |
H32 | 1.0387 | −0.1896 | 0.4262 | 0.065* | |
C33 | 0.9939 (2) | −0.4123 (9) | 0.3407 (3) | 0.0454 (13) | |
H33 | 1.0314 | −0.5261 | 0.3361 | 0.054* | |
C34 | 0.9338 (2) | −0.4371 (9) | 0.2964 (3) | 0.0441 (12) | |
H34 | 0.9297 | −0.5751 | 0.2617 | 0.053* | |
N35 | 0.87914 (19) | −0.2752 (8) | 0.2989 (2) | 0.0354 (10) | 0.40 |
C35 | 0.87914 (19) | −0.2752 (8) | 0.2989 (2) | 0.0354 (10) | 0.60 |
H35 | 0.8389 | −0.2979 | 0.2655 | 0.042* | 0.60 |
C40 | 0.65707 (19) | 0.2792 (8) | 0.2432 (2) | 0.0283 (10) | |
C41 | 0.6070 (2) | 0.4625 (8) | 0.2429 (2) | 0.0380 (11) | |
H41 | 0.6118 | 0.5930 | 0.2803 | 0.046* | |
C42 | 0.5494 (2) | 0.4669 (8) | 0.1906 (2) | 0.0393 (12) | |
H42 | 0.5163 | 0.5981 | 0.1928 | 0.047* | |
C43 | 0.54081 (19) | 0.2767 (8) | 0.1349 (2) | 0.0302 (10) | |
C44 | 0.5919 (2) | 0.0955 (9) | 0.1327 (3) | 0.0442 (12) | |
H44 | 0.5880 | −0.0321 | 0.0943 | 0.053* | |
C45 | 0.6486 (2) | 0.0961 (8) | 0.1857 (3) | 0.0411 (12) | |
H45 | 0.6827 | −0.0318 | 0.1826 | 0.049* | |
S40 | 0.46881 (5) | 0.2541 (2) | 0.06834 (6) | 0.0347 (3) | |
C46 | 0.4188 (2) | 0.5257 (8) | 0.0889 (2) | 0.0422 (12) | |
H46A | 0.4083 | 0.5279 | 0.1446 | 0.063* | |
H46B | 0.3752 | 0.5232 | 0.0571 | 0.063* | |
H46C | 0.4456 | 0.6752 | 0.0763 | 0.063* |
U11 | U22 | U33 | U12 | U13 | U23 | |
C10 | 0.032 (2) | 0.030 (2) | 0.016 (2) | −0.001 (2) | 0.0034 (18) | 0.005 (2) |
C11 | 0.048 (3) | 0.050 (3) | 0.041 (3) | 0.015 (2) | −0.006 (2) | −0.015 (3) |
C12 | 0.056 (3) | 0.071 (4) | 0.044 (3) | 0.019 (3) | −0.024 (2) | −0.021 (3) |
C13 | 0.052 (3) | 0.043 (3) | 0.019 (3) | 0.003 (2) | −0.004 (2) | −0.007 (2) |
C14 | 0.046 (3) | 0.050 (3) | 0.037 (3) | 0.014 (2) | 0.004 (2) | −0.019 (3) |
N15 | 0.043 (2) | 0.058 (3) | 0.028 (2) | 0.007 (2) | −0.0014 (17) | −0.019 (2) |
C15 | 0.043 (2) | 0.058 (3) | 0.028 (2) | 0.007 (2) | −0.0014 (17) | −0.019 (2) |
N20 | 0.0384 (19) | 0.037 (2) | 0.0137 (18) | 0.003 (2) | 0.0057 (14) | 0.0044 (19) |
C20 | 0.037 (2) | 0.034 (3) | 0.012 (2) | 0.001 (2) | 0.0076 (19) | 0.002 (2) |
C21 | 0.042 (3) | 0.029 (3) | 0.019 (2) | 0.000 (2) | 0.002 (2) | 0.001 (2) |
C22 | 0.039 (2) | 0.029 (2) | 0.013 (2) | −0.002 (2) | 0.0067 (17) | 0.004 (2) |
C23 | 0.048 (3) | 0.036 (3) | 0.013 (2) | −0.002 (2) | 0.003 (2) | −0.001 (2) |
C24 | 0.043 (3) | 0.029 (3) | 0.022 (3) | −0.002 (2) | 0.006 (2) | 0.005 (2) |
C30 | 0.039 (3) | 0.037 (3) | 0.016 (2) | 0.003 (2) | 0.0086 (19) | 0.006 (2) |
C31 | 0.056 (3) | 0.056 (3) | 0.024 (3) | 0.013 (3) | 0.001 (2) | −0.003 (2) |
C32 | 0.064 (3) | 0.071 (4) | 0.029 (3) | 0.018 (3) | 0.000 (2) | 0.007 (3) |
C33 | 0.056 (3) | 0.046 (3) | 0.035 (3) | 0.012 (3) | 0.011 (2) | 0.013 (3) |
C34 | 0.062 (3) | 0.040 (3) | 0.032 (3) | 0.003 (3) | 0.018 (3) | −0.003 (2) |
N35 | 0.048 (2) | 0.036 (2) | 0.023 (2) | 0.006 (2) | 0.0093 (18) | 0.000 (2) |
C35 | 0.048 (2) | 0.036 (2) | 0.023 (2) | 0.006 (2) | 0.0093 (18) | 0.000 (2) |
C40 | 0.039 (2) | 0.031 (3) | 0.016 (2) | −0.005 (2) | 0.0059 (17) | 0.003 (2) |
C41 | 0.053 (3) | 0.045 (3) | 0.016 (3) | 0.005 (2) | −0.002 (2) | −0.010 (2) |
C42 | 0.055 (3) | 0.041 (3) | 0.022 (3) | 0.012 (2) | 0.001 (2) | −0.007 (2) |
C43 | 0.038 (2) | 0.029 (3) | 0.024 (2) | −0.005 (2) | 0.0013 (18) | 0.004 (2) |
C44 | 0.056 (3) | 0.040 (3) | 0.036 (3) | 0.006 (3) | −0.008 (2) | −0.011 (2) |
C45 | 0.052 (3) | 0.034 (3) | 0.037 (3) | 0.010 (2) | −0.004 (2) | −0.009 (2) |
S40 | 0.0459 (6) | 0.0359 (6) | 0.0222 (6) | −0.0007 (6) | −0.0005 (4) | −0.0047 (6) |
C46 | 0.049 (3) | 0.053 (3) | 0.024 (3) | 0.009 (2) | −0.003 (2) | −0.003 (2) |
C10—N15 | 1.342 (5) | C31—C32 | 1.367 (6) |
C10—C11 | 1.374 (5) | C31—H31 | 0.9500 |
C10—C20 | 1.509 (5) | C32—C33 | 1.399 (6) |
C11—C12 | 1.394 (6) | C32—H32 | 0.9500 |
C11—H11 | 0.9500 | C33—C34 | 1.360 (6) |
C12—C13 | 1.343 (6) | C33—H33 | 0.9500 |
C12—H12 | 0.9500 | C34—N35 | 1.364 (5) |
C13—C14 | 1.357 (5) | C34—H34 | 0.9500 |
C13—H13 | 0.9500 | C40—C41 | 1.375 (5) |
C14—N15 | 1.371 (5) | C40—C45 | 1.393 (5) |
C14—H14 | 0.9500 | C41—C42 | 1.392 (5) |
N20—C20 | 1.324 (5) | C41—H41 | 0.9500 |
N20—C24 | 1.355 (5) | C42—C43 | 1.401 (6) |
C20—C21 | 1.391 (5) | C42—H42 | 0.9500 |
C21—C22 | 1.402 (5) | C43—C44 | 1.381 (6) |
C21—H21 | 0.9500 | C43—S40 | 1.758 (4) |
C22—C23 | 1.378 (5) | C44—C45 | 1.388 (6) |
C22—C40 | 1.485 (5) | C44—H44 | 0.9500 |
C23—C24 | 1.398 (5) | C45—H45 | 0.9500 |
C23—H23 | 0.9500 | S40—C46 | 1.787 (4) |
C24—C30 | 1.472 (5) | C46—H46A | 0.9800 |
C30—C31 | 1.380 (6) | C46—H46B | 0.9800 |
C30—N35 | 1.382 (5) | C46—H46C | 0.9800 |
N15—C10—C11 | 120.9 (4) | C30—C31—H31 | 118.9 |
N15—C10—C20 | 118.8 (4) | C31—C32—C33 | 119.5 (5) |
C11—C10—C20 | 120.1 (4) | C31—C32—H32 | 120.3 |
C10—C11—C12 | 119.0 (4) | C33—C32—H32 | 120.3 |
C10—C11—H11 | 120.5 | C34—C33—C32 | 117.3 (5) |
C12—C11—H11 | 120.5 | C34—C33—H33 | 121.3 |
C13—C12—C11 | 120.1 (4) | C32—C33—H33 | 121.3 |
C13—C12—H12 | 120.0 | C33—C34—N35 | 123.8 (5) |
C11—C12—H12 | 120.0 | C33—C34—H34 | 118.1 |
C12—C13—C14 | 119.4 (4) | N35—C34—H34 | 118.1 |
C12—C13—H13 | 120.3 | C34—N35—C30 | 118.9 (4) |
C14—C13—H13 | 120.3 | C41—C40—C45 | 116.1 (4) |
C13—C14—N15 | 121.8 (4) | C41—C40—C22 | 122.4 (4) |
C13—C14—H14 | 119.1 | C45—C40—C22 | 121.5 (4) |
N15—C14—H14 | 119.1 | C40—C41—C42 | 123.4 (4) |
C10—N15—C14 | 118.8 (4) | C40—C41—H41 | 118.3 |
C20—N20—C24 | 117.9 (3) | C42—C41—H41 | 118.3 |
N20—C20—C21 | 123.7 (4) | C41—C42—C43 | 119.5 (4) |
N20—C20—C10 | 116.4 (3) | C41—C42—H42 | 120.2 |
C21—C20—C10 | 119.9 (4) | C43—C42—H42 | 120.2 |
C20—C21—C22 | 119.4 (4) | C44—C43—C42 | 117.7 (4) |
C20—C21—H21 | 120.3 | C44—C43—S40 | 118.3 (3) |
C22—C21—H21 | 120.3 | C42—C43—S40 | 123.9 (3) |
C23—C22—C21 | 116.4 (3) | C43—C44—C45 | 121.4 (4) |
C23—C22—C40 | 122.7 (4) | C43—C44—H44 | 119.3 |
C21—C22—C40 | 120.9 (4) | C45—C44—H44 | 119.3 |
C22—C23—C24 | 121.5 (4) | C44—C45—C40 | 121.8 (4) |
C22—C23—H23 | 119.3 | C44—C45—H45 | 119.1 |
C24—C23—H23 | 119.3 | C40—C45—H45 | 119.1 |
N20—C24—C23 | 121.1 (4) | C43—S40—C46 | 103.4 (2) |
N20—C24—C30 | 116.8 (4) | S40—C46—H46A | 109.5 |
C23—C24—C30 | 122.1 (4) | S40—C46—H46B | 109.5 |
C31—C30—N35 | 118.2 (4) | H46A—C46—H46B | 109.5 |
C31—C30—C24 | 121.9 (4) | S40—C46—H46C | 109.5 |
N35—C30—C24 | 119.8 (4) | H46A—C46—H46C | 109.5 |
C32—C31—C30 | 122.2 (5) | H46B—C46—H46C | 109.5 |
C32—C31—H31 | 118.9 |
Experimental details
Crystal data | |
Chemical formula | C23H18N2S |
Mr | 354.45 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 93 |
a, b, c (Å) | 19.189 (3), 5.3617 (8), 17.084 (3) |
β (°) | 92.262 (9) |
V (Å3) | 1756.3 (5) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.19 |
Crystal size (mm) | 0.45 × 0.17 × 0.04 |
Data collection | |
Diffractometer | Bruker APEXII CCD area-detector |
Absorption correction | Multi-scan (SADABS; Bruker, 2007) |
Tmin, Tmax | 0.599, 0.992 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 19871, 3118, 1442 |
Rint | 0.121 |
(sin θ/λ)max (Å−1) | 0.596 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.063, 0.161, 0.93 |
No. of reflections | 3118 |
No. of parameters | 236 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.50, −0.35 |
Computer programs: APEX2 (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 1990), SHELXL97 (Sheldrick, 1997), ORTEP-3 for Windows (Version 1.08; Farrugia, 1997), publCIF (Westrip, 2008).
Acknowledgements
We thank the Foundation of Research Science and Technology for funding. FS also thanks the EC for funding (grant G5RD-CT-2002-00776, MWFM) and PJS also thanks the Royal Society of New Zealand for the award of a James Cook Research Fellowship.
References
Bruker (2007). APEX2 (Version 2.1-4), SAINT (Version 7.34A) and SADABS (Version 2004/1). Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565. CrossRef IUCr Journals Google Scholar
Fitchett, C. M., Richardson, C. & Steel, P. J. (2005). Org. Biomol. Chem. 3, 498–502. Web of Science CSD CrossRef PubMed CAS Google Scholar
Sheldrick, G. M. (1990). Acta Cryst. A46, 467–473. CrossRef CAS Web of Science IUCr Journals Google Scholar
Sheldrick, G. M. (1997). SHELXL97. University of Göttingen, Germany. Google Scholar
Westrip, S. P. (2008). publCIF. In preparation. Google Scholar
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The use of Self Assemblied Monolayers (SAMs) in the fabrication of molecular devices is a rapidly expanding field. To incorporate the useful photophysical properties of iridium complexes into a SAM, ligands must be capable of attaching to a surface. The compound (1), a bipyridine based ligand, includes a protected thiol group for attachment to a gold surface and a phenyl group for cyclometallation. Typically bipyridine ligands crystallize with the pyridine N atoms in a s-trans arrangement (Fitchett et al., 2005). This is attributed to reduction of C—H/H—C interactions. Here, the pyridine ring and the phenyl ring crystallize in identical conformations, leading to disorder. If C—H/H—C interactions were the dominant force for the arrangement of the ring, one would expect the phenyl ring to adopt a different arrangement due to the additional interaction. This implies that the dominant force for the arrangement of the rings is the attractive C—H/N interaction.