
Acta Cryst. (2010). E66, o2116 [ doi:10.1107/S160053681002876X ]
In the title compound, C21H21AsS3, the three benzene rings make dihedral angles of 88.41 (10), 87.75 (9) and 74.74 (10)° with each other. The methylsulfanyl groups are roughly coplanar with their attached benzene rings [C-S-C-C torsion angles = -7.6 (2), 11.2 (2) and 4.1 (2)°]. In the crystal, weak C-H
interactions link the molecules.
The reactions were conducted under an atmosphere of high purity nitrogen using standard Schlenk techniques and tetrahydrofuran (THF) dried over sodium metal. Tris(4-(methylsulfanyl)phenyl)arsine was prepared from arsenic trichloride and 4-(methylsulfanyl)phenylmagnesium bromide in tetrahydrofuran. Colourless blocks of (I) were obtained by slow evaporation from a chloroform solution.
All hydrogen atoms were positioned geometrically and refined using a riding model with C–H = 0.93 or 0.96 Å and Uiso(H) = 1.2 or 1.5Ueq(C). The rotating group model was applied to the methyl groups.
Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).
| Fig. 1. The molecular structure of (I) with 50% probability ellipsoids for non-H atoms. |
| Fig. 2. The crystal packing of (I), viewed down the a axis, showing the molecules are stacked along a axis. |
| C21H21AsS3 | F(000) = 912 |
| Mr = 444.48 | Dx = 1.436 Mg m−3 |
| Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
| Hall symbol: -P 2ybc | Cell parameters from 6720 reflections |
| a = 11.0839 (2) Å | θ = 2.7–31.0° |
| b = 11.4556 (2) Å | µ = 1.96 mm−1 |
| c = 17.3247 (2) Å | T = 100 K |
| β = 110.860 (1)° | Block, colourless |
| V = 2055.58 (6) Å3 | 0.35 × 0.13 × 0.11 mm |
| Z = 4 |
| Bruker SMART APEXII CCD diffractometer | 7111 independent reflections |
| Radiation source: fine-focus sealed tube | 5098 reflections with I > 2σ(I) |
| graphite | Rint = 0.051 |
| φ and ω scans | θmax = 32.0°, θmin = 2.0° |
| Absorption correction: multi-scan (SADABS; Bruker, 2009) | h = −16→16 |
| Tmin = 0.545, Tmax = 0.821 | k = −11→17 |
| 31130 measured reflections | l = −25→25 |
| 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)] = 0.039 | Hydrogen site location: inferred from neighbouring sites |
| wR(F2) = 0.097 | H-atom parameters constrained |
| S = 1.00 | w = 1/[σ2(Fo2) + (0.0486P)2] where P = (Fo2 + 2Fc2)/3 |
| 7111 reflections | (Δ/σ)max = 0.001 |
| 229 parameters | Δρmax = 0.86 e Å−3 |
| 0 restraints | Δρmin = −0.51 e Å−3 |
| C21H21AsS3 | V = 2055.58 (6) Å3 |
| Mr = 444.48 | Z = 4 |
| Monoclinic, P21/c | Mo Kα radiation |
| a = 11.0839 (2) Å | µ = 1.96 mm−1 |
| b = 11.4556 (2) Å | T = 100 K |
| c = 17.3247 (2) Å | 0.35 × 0.13 × 0.11 mm |
| β = 110.860 (1)° |
| Bruker SMART APEXII CCD diffractometer | 7111 independent reflections |
| Absorption correction: multi-scan (SADABS; Bruker, 2009) | 5098 reflections with I > 2σ(I) |
| Tmin = 0.545, Tmax = 0.821 | Rint = 0.051 |
| 31130 measured reflections | θmax = 32.0° |
| R[F2 > 2σ(F2)] = 0.039 | H-atom parameters constrained |
| wR(F2) = 0.097 | Δρmax = 0.86 e Å−3 |
| S = 1.00 | Δρmin = −0.51 e Å−3 |
| 7111 reflections | Absolute structure: ? |
| 229 parameters | Flack parameter: ? |
| 0 restraints | Rogers parameter: ? |
Experimental. The crystal was placed in the cold stream of an Oxford Cryosystems Cobra open-flow nitrogen cryostat (Cosier & Glazer, 1986) operating at 100.0 (1) K. |
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 | ||
| As1 | 0.851830 (19) | 0.703422 (18) | 0.496255 (12) | 0.01802 (6) | |
| S1 | 0.60863 (5) | 1.03859 (5) | 0.17158 (3) | 0.03019 (13) | |
| S2 | 0.83788 (6) | 1.05708 (5) | 0.78874 (3) | 0.02996 (13) | |
| S3 | 1.44348 (5) | 0.76333 (6) | 0.50798 (4) | 0.03192 (14) | |
| C1 | 0.78015 (19) | 0.80668 (17) | 0.40006 (12) | 0.0183 (4) | |
| C2 | 0.64685 (19) | 0.81069 (18) | 0.35944 (13) | 0.0224 (4) | |
| H2A | 0.5944 | 0.7653 | 0.3790 | 0.027* | |
| C3 | 0.59018 (19) | 0.88051 (19) | 0.29053 (12) | 0.0234 (4) | |
| H3A | 0.5008 | 0.8824 | 0.2651 | 0.028* | |
| C4 | 0.66768 (19) | 0.94822 (18) | 0.25918 (12) | 0.0204 (4) | |
| C5 | 0.80152 (19) | 0.94533 (17) | 0.29981 (11) | 0.0192 (4) | |
| H5A | 0.8542 | 0.9905 | 0.2802 | 0.023* | |
| C6 | 0.85652 (18) | 0.87601 (17) | 0.36893 (11) | 0.0183 (4) | |
| H6A | 0.9458 | 0.8754 | 0.3952 | 0.022* | |
| C7 | 0.84768 (18) | 0.81425 (17) | 0.58127 (12) | 0.0178 (4) | |
| C8 | 0.8544 (2) | 0.77177 (19) | 0.65816 (13) | 0.0262 (5) | |
| H8A | 0.8605 | 0.6918 | 0.6680 | 0.031* | |
| C9 | 0.8520 (2) | 0.8473 (2) | 0.71996 (13) | 0.0286 (5) | |
| H9A | 0.8567 | 0.8174 | 0.7709 | 0.034* | |
| C10 | 0.84255 (19) | 0.96751 (18) | 0.70672 (12) | 0.0204 (4) | |
| C11 | 0.83575 (18) | 1.01047 (18) | 0.63009 (12) | 0.0197 (4) | |
| H11A | 0.8293 | 1.0904 | 0.6201 | 0.024* | |
| C12 | 0.83859 (18) | 0.93414 (17) | 0.56862 (12) | 0.0186 (4) | |
| H12A | 0.8343 | 0.9639 | 0.5178 | 0.022* | |
| C13 | 1.03380 (18) | 0.72022 (17) | 0.50883 (12) | 0.0178 (4) | |
| C14 | 1.0843 (2) | 0.64556 (18) | 0.46419 (12) | 0.0214 (4) | |
| H14A | 1.0332 | 0.5857 | 0.4330 | 0.026* | |
| C15 | 1.2091 (2) | 0.65933 (19) | 0.46564 (12) | 0.0230 (4) | |
| H15A | 1.2408 | 0.6092 | 0.4351 | 0.028* | |
| C16 | 1.28772 (19) | 0.74795 (19) | 0.51259 (12) | 0.0209 (4) | |
| C17 | 1.24043 (19) | 0.81979 (18) | 0.56012 (12) | 0.0198 (4) | |
| H17A | 1.2931 | 0.8768 | 0.5938 | 0.024* | |
| C18 | 1.11392 (19) | 0.80605 (17) | 0.55710 (11) | 0.0190 (4) | |
| H18A | 1.0825 | 0.8555 | 0.5881 | 0.023* | |
| C19 | 0.4396 (2) | 1.0054 (2) | 0.12929 (14) | 0.0353 (6) | |
| H19A | 0.4018 | 1.0427 | 0.0765 | 0.053* | |
| H19B | 0.3984 | 1.0333 | 0.1660 | 0.053* | |
| H19C | 0.4281 | 0.9225 | 0.1228 | 0.053* | |
| C20 | 0.7909 (3) | 1.1960 (2) | 0.73922 (14) | 0.0367 (6) | |
| H20A | 0.7705 | 1.2484 | 0.7761 | 0.055* | |
| H20B | 0.7164 | 1.1862 | 0.6899 | 0.055* | |
| H20C | 0.8606 | 1.2276 | 0.7252 | 0.055* | |
| C21 | 1.5139 (2) | 0.8774 (3) | 0.58105 (19) | 0.0518 (8) | |
| H21A | 1.5994 | 0.8937 | 0.5821 | 0.078* | |
| H21B | 1.5180 | 0.8531 | 0.6350 | 0.078* | |
| H21C | 1.4619 | 0.9465 | 0.5652 | 0.078* |
| U11 | U22 | U33 | U12 | U13 | U23 | |
| As1 | 0.01501 (10) | 0.01771 (11) | 0.02239 (10) | −0.00177 (8) | 0.00793 (8) | −0.00007 (8) |
| S1 | 0.0216 (3) | 0.0365 (3) | 0.0284 (3) | −0.0021 (2) | 0.0039 (2) | 0.0102 (2) |
| S2 | 0.0388 (3) | 0.0320 (3) | 0.0207 (2) | 0.0064 (3) | 0.0126 (2) | −0.0011 (2) |
| S3 | 0.0181 (3) | 0.0435 (4) | 0.0390 (3) | 0.0006 (2) | 0.0161 (2) | −0.0026 (3) |
| C1 | 0.0159 (9) | 0.0198 (10) | 0.0199 (9) | −0.0017 (8) | 0.0074 (7) | −0.0023 (7) |
| C2 | 0.0152 (9) | 0.0263 (11) | 0.0274 (10) | −0.0050 (8) | 0.0096 (8) | 0.0010 (8) |
| C3 | 0.0136 (9) | 0.0296 (12) | 0.0265 (10) | −0.0020 (8) | 0.0065 (8) | 0.0013 (9) |
| C4 | 0.0186 (10) | 0.0214 (10) | 0.0210 (9) | 0.0002 (8) | 0.0069 (8) | −0.0015 (8) |
| C5 | 0.0176 (9) | 0.0208 (10) | 0.0208 (9) | −0.0029 (8) | 0.0088 (7) | −0.0033 (8) |
| C6 | 0.0135 (9) | 0.0216 (10) | 0.0210 (9) | −0.0027 (7) | 0.0075 (7) | −0.0029 (8) |
| C7 | 0.0122 (9) | 0.0209 (10) | 0.0220 (9) | 0.0005 (7) | 0.0081 (7) | 0.0017 (7) |
| C8 | 0.0351 (13) | 0.0199 (11) | 0.0282 (11) | 0.0051 (9) | 0.0168 (9) | 0.0061 (8) |
| C9 | 0.0379 (13) | 0.0277 (12) | 0.0230 (10) | 0.0047 (10) | 0.0143 (9) | 0.0071 (9) |
| C10 | 0.0164 (9) | 0.0260 (11) | 0.0199 (9) | 0.0016 (8) | 0.0077 (7) | 0.0003 (8) |
| C11 | 0.0166 (9) | 0.0191 (10) | 0.0243 (9) | 0.0007 (8) | 0.0085 (8) | 0.0010 (8) |
| C12 | 0.0175 (9) | 0.0197 (10) | 0.0210 (9) | −0.0007 (8) | 0.0097 (7) | 0.0037 (7) |
| C13 | 0.0145 (9) | 0.0195 (10) | 0.0196 (9) | −0.0002 (7) | 0.0061 (7) | 0.0016 (7) |
| C14 | 0.0210 (10) | 0.0200 (10) | 0.0232 (9) | 0.0013 (8) | 0.0078 (8) | −0.0015 (8) |
| C15 | 0.0215 (10) | 0.0256 (11) | 0.0239 (10) | 0.0044 (9) | 0.0106 (8) | −0.0015 (8) |
| C16 | 0.0156 (9) | 0.0248 (11) | 0.0238 (10) | 0.0037 (8) | 0.0087 (8) | 0.0046 (8) |
| C17 | 0.0137 (9) | 0.0239 (11) | 0.0215 (9) | 0.0006 (7) | 0.0059 (7) | 0.0019 (8) |
| C18 | 0.0169 (9) | 0.0215 (10) | 0.0194 (9) | 0.0011 (8) | 0.0076 (7) | 0.0001 (7) |
| C19 | 0.0242 (12) | 0.0306 (13) | 0.0392 (13) | 0.0000 (10) | −0.0033 (10) | 0.0034 (10) |
| C20 | 0.0505 (16) | 0.0318 (14) | 0.0249 (11) | 0.0106 (11) | 0.0100 (11) | −0.0038 (9) |
| C21 | 0.0193 (12) | 0.069 (2) | 0.0692 (19) | −0.0159 (13) | 0.0189 (12) | −0.0260 (16) |
| As1—C7 | 1.9574 (19) | C9—H9A | 0.9300 |
| As1—C13 | 1.960 (2) | C10—C11 | 1.392 (3) |
| As1—C1 | 1.9660 (19) | C11—C12 | 1.387 (3) |
| S1—C4 | 1.760 (2) | C11—H11A | 0.9300 |
| S1—C19 | 1.793 (2) | C12—H12A | 0.9300 |
| S2—C10 | 1.768 (2) | C13—C18 | 1.388 (3) |
| S2—C20 | 1.795 (2) | C13—C14 | 1.397 (3) |
| S3—C16 | 1.765 (2) | C14—C15 | 1.384 (3) |
| S3—C21 | 1.793 (3) | C14—H14A | 0.9300 |
| C1—C2 | 1.393 (3) | C15—C16 | 1.395 (3) |
| C1—C6 | 1.401 (3) | C15—H15A | 0.9300 |
| C2—C3 | 1.388 (3) | C16—C17 | 1.392 (3) |
| C2—H2A | 0.9300 | C17—C18 | 1.393 (3) |
| C3—C4 | 1.402 (3) | C17—H17A | 0.9300 |
| C3—H3A | 0.9300 | C18—H18A | 0.9300 |
| C4—C5 | 1.398 (3) | C19—H19A | 0.9600 |
| C5—C6 | 1.384 (3) | C19—H19B | 0.9600 |
| C5—H5A | 0.9300 | C19—H19C | 0.9600 |
| C6—H6A | 0.9300 | C20—H20A | 0.9600 |
| C7—C12 | 1.389 (3) | C20—H20B | 0.9600 |
| C7—C8 | 1.395 (3) | C20—H20C | 0.9600 |
| C8—C9 | 1.384 (3) | C21—H21A | 0.9600 |
| C8—H8A | 0.9300 | C21—H21B | 0.9600 |
| C9—C10 | 1.394 (3) | C21—H21C | 0.9600 |
| C7—As1—C13 | 98.73 (8) | C11—C12—C7 | 121.50 (18) |
| C7—As1—C1 | 97.87 (8) | C11—C12—H12A | 119.2 |
| C13—As1—C1 | 97.15 (8) | C7—C12—H12A | 119.2 |
| C4—S1—C19 | 103.97 (10) | C18—C13—C14 | 118.11 (18) |
| C10—S2—C20 | 102.53 (10) | C18—C13—As1 | 123.30 (15) |
| C16—S3—C21 | 103.15 (11) | C14—C13—As1 | 118.53 (15) |
| C2—C1—C6 | 117.67 (18) | C15—C14—C13 | 121.01 (19) |
| C2—C1—As1 | 118.95 (14) | C15—C14—H14A | 119.5 |
| C6—C1—As1 | 123.38 (14) | C13—C14—H14A | 119.5 |
| C3—C2—C1 | 121.84 (18) | C14—C15—C16 | 120.41 (19) |
| C3—C2—H2A | 119.1 | C14—C15—H15A | 119.8 |
| C1—C2—H2A | 119.1 | C16—C15—H15A | 119.8 |
| C2—C3—C4 | 120.00 (19) | C17—C16—C15 | 119.12 (18) |
| C2—C3—H3A | 120.0 | C17—C16—S3 | 123.24 (16) |
| C4—C3—H3A | 120.0 | C15—C16—S3 | 117.64 (16) |
| C5—C4—C3 | 118.59 (18) | C16—C17—C18 | 119.79 (19) |
| C5—C4—S1 | 116.77 (15) | C16—C17—H17A | 120.1 |
| C3—C4—S1 | 124.64 (15) | C18—C17—H17A | 120.1 |
| C6—C5—C4 | 120.71 (18) | C13—C18—C17 | 121.48 (19) |
| C6—C5—H5A | 119.6 | C13—C18—H18A | 119.3 |
| C4—C5—H5A | 119.6 | C17—C18—H18A | 119.3 |
| C5—C6—C1 | 121.18 (18) | S1—C19—H19A | 109.5 |
| C5—C6—H6A | 119.4 | S1—C19—H19B | 109.5 |
| C1—C6—H6A | 119.4 | H19A—C19—H19B | 109.5 |
| C12—C7—C8 | 118.15 (18) | S1—C19—H19C | 109.5 |
| C12—C7—As1 | 122.86 (14) | H19A—C19—H19C | 109.5 |
| C8—C7—As1 | 118.99 (15) | H19B—C19—H19C | 109.5 |
| C9—C8—C7 | 120.8 (2) | S2—C20—H20A | 109.5 |
| C9—C8—H8A | 119.6 | S2—C20—H20B | 109.5 |
| C7—C8—H8A | 119.6 | H20A—C20—H20B | 109.5 |
| C8—C9—C10 | 120.74 (19) | S2—C20—H20C | 109.5 |
| C8—C9—H9A | 119.6 | H20A—C20—H20C | 109.5 |
| C10—C9—H9A | 119.6 | H20B—C20—H20C | 109.5 |
| C11—C10—C9 | 118.78 (18) | S3—C21—H21A | 109.5 |
| C11—C10—S2 | 123.63 (16) | S3—C21—H21B | 109.5 |
| C9—C10—S2 | 117.58 (15) | H21A—C21—H21B | 109.5 |
| C12—C11—C10 | 120.06 (19) | S3—C21—H21C | 109.5 |
| C12—C11—H11A | 120.0 | H21A—C21—H21C | 109.5 |
| C10—C11—H11A | 120.0 | H21B—C21—H21C | 109.5 |
| C7—As1—C1—C2 | −89.18 (16) | C8—C9—C10—S2 | 179.13 (18) |
| C13—As1—C1—C2 | 170.93 (16) | C20—S2—C10—C11 | 11.2 (2) |
| C7—As1—C1—C6 | 91.80 (17) | C20—S2—C10—C9 | −167.94 (19) |
| C13—As1—C1—C6 | −8.09 (17) | C9—C10—C11—C12 | −0.1 (3) |
| C6—C1—C2—C3 | −0.1 (3) | S2—C10—C11—C12 | −179.27 (15) |
| As1—C1—C2—C3 | −179.13 (16) | C10—C11—C12—C7 | 0.2 (3) |
| C1—C2—C3—C4 | 1.0 (3) | C8—C7—C12—C11 | −0.2 (3) |
| C2—C3—C4—C5 | −1.3 (3) | As1—C7—C12—C11 | 179.94 (14) |
| C2—C3—C4—S1 | 179.00 (16) | C7—As1—C13—C18 | −9.49 (18) |
| C19—S1—C4—C5 | 172.71 (16) | C1—As1—C13—C18 | 89.65 (17) |
| C19—S1—C4—C3 | −7.6 (2) | C7—As1—C13—C14 | 173.47 (16) |
| C3—C4—C5—C6 | 0.8 (3) | C1—As1—C13—C14 | −87.39 (16) |
| S1—C4—C5—C6 | −179.54 (15) | C18—C13—C14—C15 | −2.3 (3) |
| C4—C5—C6—C1 | 0.2 (3) | As1—C13—C14—C15 | 174.91 (15) |
| C2—C1—C6—C5 | −0.5 (3) | C13—C14—C15—C16 | 0.6 (3) |
| As1—C1—C6—C5 | 178.50 (14) | C14—C15—C16—C17 | 2.2 (3) |
| C13—As1—C7—C12 | 79.74 (17) | C14—C15—C16—S3 | −177.57 (16) |
| C1—As1—C7—C12 | −18.79 (18) | C21—S3—C16—C17 | 4.1 (2) |
| C13—As1—C7—C8 | −100.12 (17) | C21—S3—C16—C15 | −176.15 (18) |
| C1—As1—C7—C8 | 161.35 (16) | C15—C16—C17—C18 | −3.1 (3) |
| C12—C7—C8—C9 | 0.0 (3) | S3—C16—C17—C18 | 176.61 (15) |
| As1—C7—C8—C9 | 179.87 (17) | C14—C13—C18—C17 | 1.3 (3) |
| C7—C8—C9—C10 | 0.1 (3) | As1—C13—C18—C17 | −175.74 (14) |
| C8—C9—C10—C11 | −0.1 (3) | C16—C17—C18—C13 | 1.4 (3) |
| Cg1 is the centroid of the C7–C12 benzene ring. |
| D—H···A | D—H | H···A | D···A | D—H···A |
| C21—H21A···Cg1i | 0.96 | 2.55 | 3.441 (3) | 155 |
| Symmetry codes: (i) x+1, y, z. |
| Cg1 is the centroid of the C7–C12 benzene ring. |
| D—H···A | D—H | H···A | D···A | D—H···A |
| C21—H21A···Cg1i | 0.96 | 2.55 | 3.441 (3) | 155 |
| Symmetry codes: (i) x+1, y, z. |
The authors would like to thank the Malaysian Government and Universiti Sains Malaysia (USM) for the Research grant No. 1001/PJJAUH/811115. IAK is grateful to USM for a Visiting Researcher position. HKF and CSY thank USM for the Research University Golden Goose grant No. 1001/PFIZIK/811012. CSY also thanks USM for the award of a USM Fellowship.
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Trisarylarsines are used in the synthesis of osmium and ruthenium cluster derivatives (Cullen et al., 1995; Shawkataly et al., 2009a, b, 2010a, b).
The three benzene rings of the title compound (Fig. 1) make dihedral angles (C1–C6/C7–C12, C1–C6/C13–C18 and C7–C12/C13–C18) of 88.41 (10), 87.75 (9) and 74.74 (10)° with each other respectively. The methylsulfanyl groups are nearly coplanar with the attached benzene rings [torsion angles of C19–S1–C4–C3 = -7.6 (2), C20–S2–C10–C9 = 11.2 (2) and C21–S3–C16–C17 = 4.1 (2)°]. In the crystal structure, the molecules are stacked along a axis (Fig. 2). Weak intermolecular C—H···π interactions further stabilize the crystal structure (Table 1).