supplementary materials


cv5394 scheme

Acta Cryst. (2013). E69, o648    [ doi:10.1107/S1600536813007800 ]

(E)-6-(4-Chlorophenyl)-4-[(2-cyano-3-phenylallyl)sulfanyl]-2,2-difluoro-3-phenyl-1,3,2-oxazaborinin-3-ium-2-uide

M. Li, S.-W. Wang and L.-R. Wen

Abstract top

In the title compound, C25H18BClF2N2OS, the characteristic B-N and B-O bond lengths are 1.571 (3) and 1.458 (3) Å, respectively. The phenyl rings form dihedral angles of 83.1 (1) and 64.6 (1)° with the chlorophenyl ring. In the crystal, weak C-H...N, C-H...F, C-H...[pi] and [pi]-[pi] interactions [centroid-centroid distances 3.877 (6) Å between the chlorophenyl rings of neighbouring molecules] held molecules together, forming ladders along the b axis.

Comment top

Thioacetanilides being novel enaminones (Peruncheralathan et al., 2005) with four active reaction sites show structural feature of highly polarized push-pull interaction C=C double bond (Li et al., 2010). BF2 complexes, such as the Bodipy family, are most intriguing due to their outstanding optical properties, extraordinary chemical versatility, and variety of applications spanning from biolabeling (Wu et al., 2009) to solar cells (Erten-Ela et al., 2008) and nanoparticle engineering (Tokoro et al., 2010). Synthetic studies have been conducted on various phosphorescent materials with heavy metals such as iridium (Tsuboyama et al., 2003) and platinum (Lu et al., 2002) and on fluorescent boron complexes (Zhang et al., 2006). In order to explore the chemical reactivities of thioacetanilides, we obtained the title compound, (I).

In (I) (Fig. 1), the B1–N2 bond length (1.571 (3) Å) is more than 0.1 Å longer than the B1–O1 bond length (1.458 (3) Å) suggesting that the major resonance contribution to bonding is the alkoxy-imine form. All bond lengths and angles in (I) are normal and in a good agreement with those reported previously for related compounds (Macedo et al., 2008) The phenyl rings C10—C15 and C20—C25 form the dihedral angles of 83.1 (1) and 64.6 (1)°, respectively, with the chlorophenyl ring C1—C6.

In the crystal, π-π interactions (centroid-to-centroid distances 3.877 (6) Å between the chlorophenyl rings of neighbouring molecules) and weak intermolecular C—H···N, C—H···F and C—H···π interactions (Table 1) held molecules together.

Related literature top

For background to thioacetanilides, see: Peruncheralathan et al. (2005); Li et al. (2010); Wu et al. (2009); Erten-Ela et al. (2008); Tokoro et al. (2010); Lu et al. (2002); Tsuboyama et al. (2003); Zhang et al. (2006). For the crystal structures of related compounds, see: Macedo et al. (2008).

Experimental top

A 25 ml volumetric flask was charged with 8 ml THF and 1.01 g (5 mmol) 2-cyano-1-phenylallyl acetate. Then 1.45 g (5 mmol) 3-(4-chlorophenyl)-3-oxo-N-phenylpropane thioamide and 0.09 g (3.75 mmol) sodium hydride were added. The mixture was stirred at room temperature for 4 h, and then 8 ml BF3.Et2O (10 mmol) was added with stirring for a further 4 h at room temperature. The reaction was monitored by TLC, and after TLC indicated the completion of the reaction, the solution was filtered, and the inorganic salts were removed. The solvent of the filtrate was removed with the aid of a rotary evaporator, and the residue was purified by column chromatography on silica gel, using petroleum ether/ethyl acetate (6:1) as eluent to provide the desired product yielding 2.01 g (84%) of pure BF2 complex, m.p. 462–463 K. Analytical data: IR (KBr, cm-1): 3080, 2977, 2180, 1681, 1583, 1505, 850, 732, 699. 1H-NMR (500 MHz, CDCl3): δ (p.p.m.) 3.98 (2H, s), 6.26 (1H, s), 7.22 (1H, s), 7.32–7.33 (2H, d, J = 7.55 Hz), 7.40–7.49 (8H, m), 7.73–7.74 (2H, d, J = 7.65 Hz), 7.88–7.90 (2H, d, J = 4.28 Hz). Single crystals suitable for X-ray diffraction were obtained through slow evaporation of a solution of the pure title compound in ethanol.

Refinement top

All H atoms were found on difference maps, but placed in idealized positions (C–H = 0.95–0.99 Å), and included in the final cycles of refinement using a riding model, with Uiso(H) = 1.2Ueq(C).

Computing details top

Data collection: CrystalClear-SM Expert (Rigaku/MSC, 2008); cell refinement: CrystalClear-SM Expert (Rigaku/MSC, 2008); data reduction: CrystalClear-SM Expert (Rigaku/MSC, 2008); 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).

Figures top
[Figure 1] Fig. 1. View of (I) showing the atomic numbering and 40% probability displacement ellipsoids.
(E)-6-(4-Chlorophenyl)-4-[(2-cyano-3-phenylallyl)sulfanyl]-2,2-difluoro-3-phenyl-1,3,2-oxazaborinin-3-ium-2-uide top
Crystal data top
C25H18BClF2N2OSF(000) = 984
Mr = 478.73Dx = 1.437 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 7694 reflections
a = 9.6996 (19) Åθ = 1.5–27.5°
b = 16.290 (3) ŵ = 0.31 mm1
c = 14.168 (3) ÅT = 173 K
β = 98.71 (3)°Plate, colourless
V = 2212.9 (8) Å30.43 × 0.29 × 0.09 mm
Z = 4
Data collection top
Rigaku MM007HF
diffractometer with Saturn724+ CCD
5081 independent reflections
Radiation source: Rotating Anode4491 reflections with I > 2σ(I)
Confocal monochromatorRint = 0.052
Detector resolution: 28.5714 pixels mm-1θmax = 27.5°, θmin = 2.1°
ω scans at fixed χ = 45°h = 1212
Absorption correction: multi-scan
(CrystalClear-SM Expert; Rigaku/MSC, 2008)
k = 2021
Tmin = 0.685, Tmax = 1.000l = 1818
15558 measured reflections
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.058Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.120H-atom parameters constrained
S = 1.18 w = 1/[σ2(Fo2) + (0.0312P)2 + 1.2135P]
where P = (Fo2 + 2Fc2)/3
5081 reflections(Δ/σ)max = 0.001
298 parametersΔρmax = 0.31 e Å3
0 restraintsΔρmin = 0.23 e Å3
Crystal data top
C25H18BClF2N2OSV = 2212.9 (8) Å3
Mr = 478.73Z = 4
Monoclinic, P21/cMo Kα radiation
a = 9.6996 (19) ŵ = 0.31 mm1
b = 16.290 (3) ÅT = 173 K
c = 14.168 (3) Å0.43 × 0.29 × 0.09 mm
β = 98.71 (3)°
Data collection top
Rigaku MM007HF
diffractometer with Saturn724+ CCD
5081 independent reflections
Absorption correction: multi-scan
(CrystalClear-SM Expert; Rigaku/MSC, 2008)
4491 reflections with I > 2σ(I)
Tmin = 0.685, Tmax = 1.000Rint = 0.052
15558 measured reflectionsθmax = 27.5°
Refinement top
R[F2 > 2σ(F2)] = 0.058H-atom parameters constrained
wR(F2) = 0.120Δρmax = 0.31 e Å3
S = 1.18Δρmin = 0.23 e Å3
5081 reflectionsAbsolute structure: ?
298 parametersFlack parameter: ?
0 restraintsRogers parameter: ?
Special details top

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
Cl11.18430 (6)0.47712 (4)1.29061 (4)0.03843 (16)
S10.47463 (6)0.63647 (4)0.79190 (4)0.03476 (16)
F10.61480 (16)0.34159 (9)0.78320 (10)0.0494 (4)
F20.46844 (15)0.35602 (9)0.89236 (12)0.0531 (4)
O10.69166 (16)0.40858 (9)0.92380 (11)0.0328 (4)
N10.7666 (3)0.74393 (18)0.69117 (18)0.0609 (7)
N20.51593 (17)0.47557 (11)0.80301 (12)0.0262 (4)
C11.0468 (2)0.47953 (14)1.19668 (15)0.0274 (5)
C21.0082 (2)0.55340 (14)1.15244 (16)0.0304 (5)
H21.05580.60271.17300.036*
C30.8982 (2)0.55382 (13)1.07731 (16)0.0292 (5)
H30.86960.60411.04650.035*
C40.8293 (2)0.48155 (13)1.04648 (15)0.0250 (4)
C50.8714 (2)0.40787 (13)1.09205 (16)0.0292 (5)
H50.82560.35821.07090.035*
C60.9795 (2)0.40674 (14)1.16804 (16)0.0299 (5)
H61.00710.35681.20000.036*
C70.7153 (2)0.48088 (13)0.96488 (15)0.0248 (4)
C80.6431 (2)0.54917 (13)0.93219 (15)0.0275 (5)
H80.65670.59890.96740.033*
C90.5476 (2)0.54684 (13)0.84604 (15)0.0261 (4)
C100.4192 (2)0.47173 (13)0.71416 (15)0.0264 (4)
C110.4659 (2)0.44916 (14)0.63062 (15)0.0299 (5)
H110.56180.43760.63030.036*
C120.3708 (2)0.44347 (14)0.54681 (16)0.0332 (5)
H120.40200.42780.48900.040*
C130.2318 (2)0.46038 (15)0.54715 (17)0.0353 (5)
H130.16740.45680.48970.042*
C140.1866 (2)0.48238 (16)0.63088 (17)0.0371 (6)
H140.09070.49440.63090.044*
C150.2795 (2)0.48729 (15)0.71564 (17)0.0351 (5)
H150.24750.50120.77370.042*
C160.5544 (2)0.71958 (13)0.86749 (16)0.0305 (5)
H16A0.49940.77010.85070.037*
H16B0.54640.70610.93460.037*
C170.7407 (2)0.74202 (16)0.76730 (19)0.0392 (6)
C180.7058 (2)0.73849 (13)0.86224 (16)0.0290 (5)
C190.7974 (2)0.75408 (13)0.94089 (17)0.0298 (5)
H190.75980.74970.99880.036*
C200.9453 (2)0.77676 (13)0.95341 (18)0.0331 (5)
C211.0184 (3)0.77306 (15)1.04606 (19)0.0399 (6)
H210.97050.75811.09720.048*
C221.1595 (3)0.79076 (17)1.0647 (2)0.0497 (7)
H221.20790.78701.12810.060*
C231.2294 (3)0.81371 (17)0.9917 (3)0.0549 (8)
H231.32630.82571.00450.066*
C241.1594 (3)0.81935 (16)0.8998 (2)0.0525 (8)
H241.20830.83510.84940.063*
C251.0182 (3)0.80214 (15)0.8805 (2)0.0412 (6)
H250.97030.80760.81720.049*
B10.5719 (3)0.39255 (16)0.85061 (19)0.0319 (6)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl10.0282 (3)0.0561 (4)0.0277 (3)0.0032 (2)0.0063 (2)0.0049 (3)
S10.0339 (3)0.0328 (3)0.0334 (3)0.0042 (2)0.0084 (2)0.0026 (2)
F10.0668 (10)0.0414 (8)0.0339 (8)0.0178 (7)0.0125 (7)0.0125 (6)
F20.0451 (9)0.0497 (9)0.0622 (11)0.0141 (7)0.0003 (7)0.0157 (8)
O10.0389 (9)0.0252 (8)0.0294 (9)0.0015 (7)0.0102 (7)0.0042 (6)
N10.0547 (15)0.090 (2)0.0404 (15)0.0242 (14)0.0130 (11)0.0166 (13)
N20.0249 (9)0.0321 (10)0.0201 (9)0.0005 (7)0.0013 (7)0.0020 (7)
C10.0232 (10)0.0402 (12)0.0181 (11)0.0031 (9)0.0005 (8)0.0029 (9)
C20.0307 (11)0.0330 (12)0.0266 (12)0.0051 (9)0.0020 (9)0.0050 (9)
C30.0328 (11)0.0278 (11)0.0256 (12)0.0010 (9)0.0003 (9)0.0007 (9)
C40.0265 (10)0.0281 (11)0.0197 (11)0.0020 (8)0.0014 (8)0.0020 (8)
C50.0317 (11)0.0278 (11)0.0266 (12)0.0011 (9)0.0004 (8)0.0011 (9)
C60.0325 (11)0.0287 (11)0.0265 (12)0.0060 (9)0.0014 (9)0.0004 (9)
C70.0277 (10)0.0263 (11)0.0202 (11)0.0026 (8)0.0029 (8)0.0011 (8)
C80.0294 (11)0.0279 (11)0.0229 (11)0.0006 (9)0.0029 (8)0.0035 (8)
C90.0246 (10)0.0308 (11)0.0222 (11)0.0003 (8)0.0011 (8)0.0006 (8)
C100.0266 (10)0.0297 (11)0.0214 (11)0.0042 (9)0.0011 (8)0.0017 (8)
C110.0271 (11)0.0366 (12)0.0251 (12)0.0038 (9)0.0014 (8)0.0026 (9)
C120.0390 (12)0.0392 (13)0.0210 (12)0.0095 (10)0.0036 (9)0.0018 (9)
C130.0352 (12)0.0430 (14)0.0245 (12)0.0097 (10)0.0061 (9)0.0050 (10)
C140.0254 (11)0.0512 (15)0.0326 (13)0.0026 (10)0.0020 (9)0.0011 (11)
C150.0278 (11)0.0507 (15)0.0267 (13)0.0038 (10)0.0035 (9)0.0049 (10)
C160.0297 (11)0.0288 (11)0.0317 (13)0.0074 (9)0.0002 (9)0.0004 (9)
C170.0345 (12)0.0473 (15)0.0353 (15)0.0106 (11)0.0041 (10)0.0065 (11)
C180.0318 (11)0.0246 (10)0.0311 (12)0.0071 (9)0.0066 (9)0.0030 (9)
C190.0331 (11)0.0248 (11)0.0317 (13)0.0024 (9)0.0058 (9)0.0010 (9)
C200.0330 (11)0.0214 (10)0.0449 (15)0.0013 (9)0.0061 (10)0.0002 (10)
C210.0380 (13)0.0353 (13)0.0452 (16)0.0021 (10)0.0029 (11)0.0054 (11)
C220.0386 (14)0.0444 (15)0.0616 (19)0.0029 (12)0.0067 (12)0.0058 (13)
C230.0334 (13)0.0383 (15)0.092 (3)0.0078 (12)0.0072 (14)0.0011 (15)
C240.0411 (14)0.0341 (14)0.086 (2)0.0042 (12)0.0215 (15)0.0109 (14)
C250.0397 (13)0.0314 (13)0.0536 (17)0.0016 (10)0.0105 (11)0.0096 (11)
B10.0342 (13)0.0305 (13)0.0284 (14)0.0032 (11)0.0040 (10)0.0041 (10)
Geometric parameters (Å, º) top
Cl1—C11.736 (2)C11—C121.392 (3)
S1—C91.748 (2)C11—H110.9500
S1—C161.824 (2)C12—C131.377 (3)
F1—B11.376 (3)C12—H120.9500
F2—B11.375 (3)C13—C141.373 (3)
O1—C71.318 (2)C13—H130.9500
O1—B11.458 (3)C14—C151.391 (3)
N1—C171.144 (3)C14—H140.9500
N2—C91.326 (3)C15—H150.9500
N2—C101.453 (3)C16—C181.513 (3)
N2—B11.571 (3)C16—H16A0.9900
C1—C21.382 (3)C16—H16B0.9900
C1—C61.384 (3)C17—C181.437 (3)
C2—C31.388 (3)C18—C191.340 (3)
C2—H20.9500C19—C201.466 (3)
C3—C41.391 (3)C19—H190.9500
C3—H30.9500C20—C211.396 (3)
C4—C51.394 (3)C20—C251.400 (3)
C4—C71.474 (3)C21—C221.384 (3)
C5—C61.385 (3)C21—H210.9500
C5—H50.9500C22—C231.372 (4)
C6—H60.9500C22—H220.9500
C7—C81.358 (3)C23—C241.377 (4)
C8—C91.417 (3)C23—H230.9500
C8—H80.9500C24—C251.384 (4)
C10—C111.380 (3)C24—H240.9500
C10—C151.381 (3)C25—H250.9500
C9—S1—C16104.75 (10)C13—C14—C15120.7 (2)
C7—O1—B1122.73 (17)C13—C14—H14119.6
C9—N2—C10120.69 (18)C15—C14—H14119.6
C9—N2—B1121.04 (17)C10—C15—C14119.0 (2)
C10—N2—B1118.08 (17)C10—C15—H15120.5
C2—C1—C6121.98 (19)C14—C15—H15120.5
C2—C1—Cl1119.43 (17)C18—C16—S1116.79 (16)
C6—C1—Cl1118.60 (17)C18—C16—H16A108.1
C1—C2—C3118.4 (2)S1—C16—H16A108.1
C1—C2—H2120.8C18—C16—H16B108.1
C3—C2—H2120.8S1—C16—H16B108.1
C2—C3—C4120.9 (2)H16A—C16—H16B107.3
C2—C3—H3119.6N1—C17—C18178.8 (3)
C4—C3—H3119.6C19—C18—C17123.4 (2)
C3—C4—C5119.35 (19)C19—C18—C16121.6 (2)
C3—C4—C7121.36 (19)C17—C18—C16115.0 (2)
C5—C4—C7119.27 (19)C18—C19—C20131.4 (2)
C6—C5—C4120.4 (2)C18—C19—H19114.3
C6—C5—H5119.8C20—C19—H19114.3
C4—C5—H5119.8C21—C20—C25117.7 (2)
C1—C6—C5119.0 (2)C21—C20—C19116.8 (2)
C1—C6—H6120.5C25—C20—C19125.4 (2)
C5—C6—H6120.5C22—C21—C20121.2 (3)
O1—C7—C8122.33 (19)C22—C21—H21119.4
O1—C7—C4114.39 (18)C20—C21—H21119.4
C8—C7—C4123.25 (19)C23—C22—C21120.0 (3)
C7—C8—C9120.5 (2)C23—C22—H22120.0
C7—C8—H8119.7C21—C22—H22120.0
C9—C8—H8119.7C22—C23—C24120.1 (3)
N2—C9—C8119.69 (19)C22—C23—H23119.9
N2—C9—S1118.65 (15)C24—C23—H23119.9
C8—C9—S1121.61 (16)C23—C24—C25120.3 (3)
C11—C10—C15120.8 (2)C23—C24—H24119.9
C11—C10—N2120.13 (19)C25—C24—H24119.9
C15—C10—N2119.0 (2)C24—C25—C20120.7 (3)
C10—C11—C12119.2 (2)C24—C25—H25119.7
C10—C11—H11120.4C20—C25—H25119.7
C12—C11—H11120.4F2—B1—F1110.8 (2)
C13—C12—C11120.4 (2)F2—B1—O1109.0 (2)
C13—C12—H12119.8F1—B1—O1108.0 (2)
C11—C12—H12119.8F2—B1—N2109.24 (19)
C14—C13—C12119.8 (2)F1—B1—N2110.0 (2)
C14—C13—H13120.1O1—B1—N2109.71 (18)
C12—C13—H13120.1
C6—C1—C2—C30.2 (3)C10—C11—C12—C130.2 (3)
Cl1—C1—C2—C3179.82 (17)C11—C12—C13—C140.5 (4)
C1—C2—C3—C40.7 (3)C12—C13—C14—C150.4 (4)
C2—C3—C4—C50.2 (3)C11—C10—C15—C142.0 (4)
C2—C3—C4—C7178.1 (2)N2—C10—C15—C14179.0 (2)
C3—C4—C5—C60.8 (3)C13—C14—C15—C101.6 (4)
C7—C4—C5—C6179.1 (2)C9—S1—C16—C1872.85 (18)
C2—C1—C6—C50.8 (3)N1—C17—C18—C19157 (14)
Cl1—C1—C6—C5178.86 (17)N1—C17—C18—C1626 (14)
C4—C5—C6—C11.3 (3)S1—C16—C18—C19137.62 (19)
B1—O1—C7—C810.5 (3)S1—C16—C18—C1745.1 (2)
B1—O1—C7—C4171.5 (2)C17—C18—C19—C200.2 (4)
C3—C4—C7—O1158.4 (2)C16—C18—C19—C20177.3 (2)
C5—C4—C7—O119.9 (3)C18—C19—C20—C21167.7 (2)
C3—C4—C7—C819.6 (3)C18—C19—C20—C2512.7 (4)
C5—C4—C7—C8162.2 (2)C25—C20—C21—C222.5 (4)
O1—C7—C8—C96.2 (3)C19—C20—C21—C22177.9 (2)
C4—C7—C8—C9171.6 (2)C20—C21—C22—C231.1 (4)
C10—N2—C9—C8179.45 (19)C21—C22—C23—C240.1 (4)
B1—N2—C9—C85.6 (3)C22—C23—C24—C250.2 (4)
C10—N2—C9—S11.9 (3)C23—C24—C25—C201.7 (4)
B1—N2—C9—S1176.82 (16)C21—C20—C25—C242.8 (4)
C7—C8—C9—N28.1 (3)C19—C20—C25—C24177.7 (2)
C7—C8—C9—S1169.38 (17)C7—O1—B1—F297.9 (2)
C16—S1—C9—N2175.52 (17)C7—O1—B1—F1141.6 (2)
C16—S1—C9—C82.0 (2)C7—O1—B1—N221.6 (3)
C9—N2—C10—C11112.8 (2)C9—N2—B1—F2100.3 (2)
B1—N2—C10—C1172.1 (3)C10—N2—B1—F274.8 (3)
C9—N2—C10—C1570.1 (3)C9—N2—B1—F1137.9 (2)
B1—N2—C10—C15105.0 (2)C10—N2—B1—F147.0 (3)
C15—C10—C11—C121.1 (3)C9—N2—B1—O119.2 (3)
N2—C10—C11—C12178.1 (2)C10—N2—B1—O1165.75 (18)
Hydrogen-bond geometry (Å, º) top
Cg1 is the centroid of the C1–C6 ring.
D—H···AD—HH···AD···AD—H···A
C16—H16A···F1i0.992.353.184 (3)141
C21—H21···N1ii0.952.553.434 (4)156
C15—H15···Cg1iii0.952.523.394 (5)153
Symmetry codes: (i) x+1, y+1/2, z+3/2; (ii) x, y+3/2, z+1/2; (iii) x+1, y+1, z.
Hydrogen-bond geometry (Å, º) top
Cg1 is the centroid of the C1–C6 ring.
D—H···AD—HH···AD···AD—H···A
C16—H16A···F1i0.992.353.184 (3)140.8
C21—H21···N1ii0.952.553.434 (4)155.6
C15—H15···Cg1iii0.952.523.394 (5)153.0
Symmetry codes: (i) x+1, y+1/2, z+3/2; (ii) x, y+3/2, z+1/2; (iii) x+1, y+1, z.
references
References top

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