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Acta Crystallogr Sect E Struct Rep Online. 2008 August 1; 64(Pt 8): o1430–o1431.
Published online 2008 July 9. doi:  10.1107/S1600536808018722
PMCID: PMC2962063

5′,6-Dichloro-1′,3′,3′-trimethyl­spiro­[2H-1-benzopyran-2,2′-indoline]

Abstract

In the crystal structure of the title compound, C19H17Cl2NO, the indoline and benzopyran ring systems are approximately perpendicular to each other. The indoline ring is in an envelope conformation with the spiro C atom as the flap. The N atom of the indoline ring forms a pyramidal environment, the sum of the angles at this atom being 352.46°.

Related literature

For related literature, see: Crano & Guglielmetti (1999 [triangle]); Kholmanskii & Dyumanev (1987 [triangle]); Tamai & Miyasaka (2000 [triangle]); Krongauz et al. (2000 [triangle]); Minkin (2004 [triangle]); Crano et al. (1996 [triangle]); Dvornikov et al. (1994 [triangle]); Tamai & Miyasaka (2000 [triangle]); Yoshida & Morinaka (1994 [triangle]); Willner et al. (1993 [triangle]); Byrne et al. (2006a [triangle],b [triangle]); Raić-Malić et al. (2004 [triangle]); Aldoshin & Atovmyan (1985 [triangle]); Aldoshin et al. (1987 [triangle]); Mannschreeck et al. (1999 [triangle]). For the synthesis of the title compound, see: Martin et al. (1998 [triangle]).

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Object name is e-64-o1430-scheme1.jpg

Experimental

Crystal data

  • C19H17Cl2NO
  • M r = 346.24
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-64-o1430-efi1.jpg
  • a = 8.3105 (7) Å
  • b = 18.2576 (16) Å
  • c = 11.1921 (10) Å
  • β = 104.770 (2)°
  • V = 1642.1 (2) Å3
  • Z = 4
  • Mo Kα radiation
  • μ = 0.40 mm−1
  • T = 100 (2) K
  • 0.50 × 0.40 × 0.05 mm

Data collection

  • Bruker SMART CCD area-detector diffractometer
  • Absorption correction: multi-scan (SADABS; Sheldrick, 2000 [triangle]) T min = 0.740, T max = 0.980
  • 16175 measured reflections
  • 4312 independent reflections
  • 3857 reflections with I > 2σ(I)
  • R int = 0.023

Refinement

  • R[F 2 > 2σ(F 2)] = 0.046
  • wR(F 2) = 0.122
  • S = 1.05
  • 4312 reflections
  • 276 parameters
  • All H-atom parameters refined
  • Δρmax = 0.96 e Å−3
  • Δρmin = −0.25 e Å−3

Data collection: SMART (Bruker, 2007 [triangle]); cell refinement: SAINT (Bruker, 2007 [triangle]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: DIAMOND (Brandenburg, 2001 [triangle]); software used to prepare material for publication: publCIF (Westrip, 2008 [triangle]).

Table 1
Selected interplanar angles (°) for the title compound

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536808018722/nc2106sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536808018722/nc2106Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Acknowledgments

This work was supported financially by the Science Found­ation of Ireland (grant SFI 03/IN3/1361) and the Environmental Protection Agency (grant 2004-RS-AIC-M4).

supplementary crystallographic information

Comment

Spiropyrans are a family of organic photochromic compounds (Carno & Guglielmetti, 1998). This family of compounds are well studied and documented (Kholmanskii & Dyumanev, 1987; Tamai & Miyasaka, 2000; Krongauz et al., 2000; Minkin, 2004) because they can be converted from a closed colourless form into a strongly coloured open form using UV irradiation. This tremendous characteristic of spiropyran compounds has been utilized by scientists for many applications such as light-sensitive eyewear (Crano et al., 1996), high density optical storage (Dvornikov et al.,1994), molecular switches (Tamai & Miyasaka, 2000, Minkin, 2004) and molecular devices (Yoshida & Morinaka, 1994; Willner et al., 1993). Our main interest was utilizing spiropyran derivatives as transducers in optical sensors, where selective binding to certain metal ions was achieved. The binding and release of such ions can be controlled by exposure to light of around 380 nm (open form) and 550 nm (close form) respectively (Byrne et al., 2006a; Byrne et al., 2006b). The title compound was envisaged as an intermediate in the synthesis of further spiropyran derivatives, whereby the chlorides groups can be replaced by substitution with variety of functional groups. The title compound consists of two molecular fragments: An indoline ring linked to a benzopyran ring by the spiro (C11) atom (Fig 1). The two fragments are almost perpendicular to each other (Table 2). The bond lengths of (C11—N) and (C11—O) are both approximately equal, which agrees with previous reports (Raić-Malić et al., 2004; Aldoshin & Atovmyan, 1985; Aldoshin et al., 1987). The spiro carbon atom (C11) is out of the plane of the other four indoline ring atoms (Table 2). The indoline ring is quite coplanar with the fused benzene ring (Table 2). The sum of the angles of the nitrogen atom at the indoline moiety is 352.46°, which indicates a pyramidal arrangement about this atom. These results are in agreement with previous reports (Raić-Malić et al., 2004).

Experimental

The title compound was originally synthesized according to a method outlined in a patent (Martin et al., 1998). Our procedure differs from the original synthesis, especially with regard to the purification process. Single crystals suitable for X-ray diffraction were grown by slow evaporation from ethanol solution.

To 5-chlorosalicylaldehyde (1.53 g, 9.6 mmol) in 10 ml e thanol, a solution of 5-chloro-2-methylene-1,3,3-trimethylindoline (1.95 ml, 9.6 mmol) in 20 ml of ethanol was added slowly, over 30 min. This reaction mixture was heated to reflux over 24 h and then cooled down to ambient temperature. The solvent was evaporated by vacuum and the resulting crude compound was purified by column chromatography from the system solvent of 1:5, ethyl acetate: hexane, yielding a white powder (2.30 g, 69.4%).

Refinement

All hydrogen atoms were located in the difference fourier map and allowed to refine isotropic without any restraints. C—H bond lenghts vary from 0.92 (2) to 1.00 (2) Å.

Figures

Fig. 1.
A perspective view of the asymmetric unit of title compound, showing the atom numbering and thermal ellipsoids at a 50% probability level.

Crystal data

C19H17Cl2NOF000 = 720
Mr = 346.24Dx = 1.401 Mg m3
Monoclinic, P21/cMo Kα radiation λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 7373 reflections
a = 8.3105 (7) Åθ = 2.2–31.7º
b = 18.2576 (16) ŵ = 0.40 mm1
c = 11.1921 (10) ÅT = 100 (2) K
β = 104.770 (2)ºPlate, colourless
V = 1642.1 (2) Å30.50 × 0.40 × 0.05 mm
Z = 4

Data collection

Bruker SMART CCD area-detector diffractometer4312 independent reflections
Radiation source: fine-focus sealed tube3857 reflections with I > 2σ(I)
Monochromator: graphiteRint = 0.023
Detector resolution: 8.366 pixels mm-1θmax = 29.0º
T = 100(2) Kθmin = 2.2º
[var phi] and ω scansh = −11→11
Absorption correction: multi-scan(SADABS; Sheldrick, 2000)k = −24→24
Tmin = 0.740, Tmax = 0.980l = −15→15
16175 measured reflections

Refinement

Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.046All H-atom parameters refined
wR(F2) = 0.122  w = 1/[σ2(Fo2) + (0.0653P)2 + 1.2622P] where P = (Fo2 + 2Fc2)/3
S = 1.05(Δ/σ)max = 0.002
4312 reflectionsΔρmax = 0.96 e Å3
276 parametersΔρmin = −0.25 e Å3
Primary atom site location: structure-invariant direct methodsExtinction correction: none

Special details

Experimental. 1H NMR δ(CDCl3); 1.190 (S, 3H, CH3), 1.30 (S, 3H, CH~3~),2.72 (S, 3H, CH3), 5.73 (d, 1H, J= 10.4 Hz, CH=CH), 6.46 ( d, H, J= 12.8 Hz, Ar-H), 6.67 (d, 1H, J =9.6 Hz, Ar-H), 6.83 (d, 1H, J = 16.4, Ar-H), 7.01-7.08 ( m, 2H, Ar-H), 7.15 ( d, 1H, J = 10.4 Hz, CH=CH).13C NMR δ(CDCl3); 19.95, 25.68, 29.04, 51.96, 104.60, 107.78, 116.33, 119.91,120.17, 122.11, 123.93, 124.85, 126.28, 127.37, 128.80, 129.50, 138.53, 146.73,152.80.M.S. (m/z ion) (m/z 346.2).
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)

xyzUiso*/Ueq
Cl11.29108 (6)0.46363 (2)0.01666 (4)0.02892 (13)
C11.2126 (2)0.38771 (9)0.07835 (15)0.0198 (3)
C21.0760 (2)0.39650 (9)0.12870 (15)0.0187 (3)
H21.029 (3)0.4437 (13)0.133 (2)0.025 (5)*
C31.01780 (19)0.33524 (8)0.17644 (14)0.0160 (3)
C41.09359 (19)0.26690 (8)0.17419 (14)0.0169 (3)
C51.2295 (2)0.25851 (9)0.12441 (16)0.0202 (3)
H51.284 (3)0.2115 (12)0.120 (2)0.020 (5)*
C61.2886 (2)0.32043 (10)0.07558 (16)0.0223 (3)
H61.381 (3)0.3155 (12)0.037 (2)0.024 (5)*
N1.01339 (17)0.21423 (7)0.22743 (13)0.0186 (3)
C71.0459 (2)0.13674 (9)0.21878 (17)0.0225 (3)
H7A1.015 (3)0.1214 (13)0.136 (2)0.029 (6)*
H7B0.989 (3)0.1089 (13)0.271 (2)0.030 (6)*
H7C1.163 (3)0.1284 (14)0.256 (2)0.038 (7)*
C80.88187 (19)0.32673 (8)0.24368 (14)0.0150 (3)
C90.9546 (2)0.34836 (9)0.37930 (15)0.0197 (3)
H9A0.989 (3)0.3981 (13)0.383 (2)0.024 (5)*
H9B0.870 (3)0.3426 (12)0.427 (2)0.027 (6)*
H9C1.051 (3)0.3191 (13)0.419 (2)0.029 (6)*
C100.7265 (2)0.37244 (10)0.18951 (16)0.0204 (3)
H10A0.687 (3)0.3635 (12)0.100 (2)0.022 (5)*
H10B0.756 (3)0.4243 (13)0.202 (2)0.028 (6)*
H10C0.647 (3)0.3607 (12)0.233 (2)0.023 (5)*
C110.85232 (19)0.24213 (9)0.23280 (14)0.0163 (3)
O0.73274 (14)0.23176 (6)0.11246 (10)0.0178 (2)
C120.7959 (2)0.20568 (9)0.33518 (15)0.0194 (3)
H120.853 (3)0.2181 (12)0.417 (2)0.025 (5)*
C130.6788 (2)0.15405 (9)0.31410 (15)0.0200 (3)
H130.651 (3)0.1291 (13)0.381 (2)0.028 (6)*
C140.5891 (2)0.13478 (8)0.18904 (15)0.0166 (3)
C150.61892 (19)0.17667 (8)0.09238 (14)0.0147 (3)
C160.52518 (19)0.16618 (9)−0.02828 (14)0.0159 (3)
H160.550 (3)0.1972 (12)−0.090 (2)0.021 (5)*
C170.4051 (2)0.11154 (9)−0.05435 (15)0.0185 (3)
H170.345 (2)0.1032 (11)−0.1356 (18)0.014 (5)*
C180.38016 (19)0.06811 (8)0.04128 (16)0.0183 (3)
Cl20.23079 (5)−0.00073 (2)0.00933 (4)0.02523 (13)
C190.4695 (2)0.07902 (9)0.16192 (16)0.0188 (3)
H190.452 (3)0.0512 (12)0.226 (2)0.022 (5)*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
Cl10.0321 (2)0.0223 (2)0.0349 (2)−0.00767 (16)0.01332 (18)0.00340 (17)
C10.0173 (7)0.0211 (8)0.0209 (7)−0.0046 (6)0.0047 (6)0.0022 (6)
C20.0180 (7)0.0160 (7)0.0208 (7)−0.0002 (6)0.0026 (6)−0.0016 (6)
C30.0129 (7)0.0172 (7)0.0165 (7)−0.0009 (5)0.0015 (5)−0.0014 (5)
C40.0145 (7)0.0176 (7)0.0171 (7)−0.0003 (5)0.0016 (5)−0.0016 (5)
C50.0152 (7)0.0200 (8)0.0248 (8)0.0016 (6)0.0041 (6)−0.0025 (6)
C60.0174 (8)0.0249 (8)0.0248 (8)−0.0022 (6)0.0061 (6)−0.0025 (6)
N0.0187 (6)0.0149 (6)0.0224 (7)0.0011 (5)0.0054 (5)−0.0002 (5)
C70.0284 (9)0.0143 (7)0.0252 (8)0.0031 (6)0.0078 (7)0.0011 (6)
C80.0141 (7)0.0149 (7)0.0158 (7)−0.0007 (5)0.0033 (5)−0.0021 (5)
C90.0205 (8)0.0199 (8)0.0178 (7)−0.0011 (6)0.0032 (6)−0.0037 (6)
C100.0157 (7)0.0213 (8)0.0240 (8)0.0019 (6)0.0048 (6)0.0012 (6)
C110.0179 (7)0.0166 (7)0.0134 (7)−0.0020 (5)0.0022 (5)−0.0011 (5)
O0.0204 (5)0.0194 (6)0.0125 (5)−0.0082 (4)0.0023 (4)0.0001 (4)
C120.0235 (8)0.0199 (7)0.0145 (7)−0.0006 (6)0.0045 (6)−0.0002 (6)
C130.0231 (8)0.0203 (8)0.0180 (7)−0.0001 (6)0.0080 (6)0.0026 (6)
C140.0169 (7)0.0147 (7)0.0190 (7)0.0010 (5)0.0058 (6)0.0003 (5)
C150.0133 (6)0.0134 (6)0.0182 (7)−0.0001 (5)0.0056 (5)−0.0013 (5)
C160.0132 (7)0.0173 (7)0.0171 (7)0.0004 (5)0.0039 (5)−0.0006 (5)
C170.0143 (7)0.0182 (7)0.0216 (8)0.0001 (6)0.0018 (6)−0.0028 (6)
C180.0122 (7)0.0117 (6)0.0308 (8)−0.0002 (5)0.0052 (6)−0.0012 (6)
Cl20.0158 (2)0.01421 (19)0.0436 (3)−0.00319 (13)0.00372 (17)0.00058 (15)
C190.0179 (7)0.0146 (7)0.0256 (8)0.0007 (6)0.0086 (6)0.0034 (6)

Geometric parameters (Å, °)

Cl1—C11.7474 (17)C9—H9C0.97 (2)
C1—C61.385 (2)C10—H10A0.98 (2)
C1—C21.399 (2)C10—H10B0.98 (2)
C2—C31.379 (2)C10—H10C0.94 (2)
C2—H20.95 (2)C11—O1.4680 (18)
C3—C41.401 (2)C11—C121.500 (2)
C3—C81.517 (2)O—C151.3596 (18)
C4—N1.388 (2)C12—C131.332 (2)
C4—C51.389 (2)C12—H120.94 (2)
C5—C61.398 (2)C13—C141.451 (2)
C5—H50.98 (2)C13—H130.95 (2)
C6—H60.98 (2)C14—C151.397 (2)
N—C111.448 (2)C14—C191.401 (2)
N—C71.448 (2)C15—C161.390 (2)
C7—H7A0.94 (2)C16—C171.389 (2)
C7—H7B0.98 (2)C16—H160.96 (2)
C7—H7C0.96 (3)C17—C181.389 (2)
C8—C101.527 (2)C17—H170.93 (2)
C8—C91.535 (2)C18—C191.379 (2)
C8—C111.564 (2)C18—Cl21.7384 (16)
C9—H9A0.95 (2)C19—H190.92 (2)
C9—H9B1.00 (2)
C6—C1—C2122.16 (15)H9B—C9—H9C107.9 (19)
C6—C1—Cl1118.44 (13)C8—C10—H10A109.9 (13)
C2—C1—Cl1119.41 (13)C8—C10—H10B108.3 (14)
C3—C2—C1117.62 (15)H10A—C10—H10B108.3 (18)
C3—C2—H2121.6 (14)C8—C10—H10C107.7 (14)
C1—C2—H2120.7 (14)H10A—C10—H10C113.3 (18)
C2—C3—C4120.77 (15)H10B—C10—H10C109.2 (19)
C2—C3—C8130.88 (14)N—C11—O109.47 (12)
C4—C3—C8108.24 (13)N—C11—C12110.36 (13)
N—C4—C5128.63 (15)O—C11—C12111.93 (13)
N—C4—C3110.00 (14)N—C11—C8102.84 (12)
C5—C4—C3121.37 (15)O—C11—C8104.77 (12)
C4—C5—C6118.05 (15)C12—C11—C8116.89 (13)
C4—C5—H5123.3 (13)C15—O—C11121.79 (12)
C6—C5—H5118.6 (13)C13—C12—C11122.36 (15)
C1—C6—C5120.02 (15)C13—C12—H12120.5 (14)
C1—C6—H6120.4 (13)C11—C12—H12117.0 (14)
C5—C6—H6119.5 (13)C12—C13—C14120.98 (15)
C4—N—C11108.93 (13)C12—C13—H13120.8 (14)
C4—N—C7122.00 (14)C14—C13—H13118.2 (14)
C11—N—C7122.46 (14)C15—C14—C19119.07 (15)
N—C7—H7A110.4 (14)C15—C14—C13117.73 (14)
N—C7—H7B109.9 (14)C19—C14—C13123.13 (15)
H7A—C7—H7B112 (2)O—C15—C16117.17 (14)
N—C7—H7C108.0 (16)O—C15—C14122.00 (14)
H7A—C7—H7C112 (2)C16—C15—C14120.72 (14)
H7B—C7—H7C104 (2)C17—C16—C15119.88 (15)
C3—C8—C10114.10 (13)C17—C16—H16123.2 (13)
C3—C8—C9107.98 (13)C15—C16—H16116.9 (13)
C10—C8—C9109.39 (13)C16—C17—C18119.23 (15)
C3—C8—C11100.63 (12)C16—C17—H17119.9 (12)
C10—C8—C11114.13 (13)C18—C17—H17120.8 (12)
C9—C8—C11110.21 (13)C19—C18—C17121.53 (15)
C8—C9—H9A109.3 (13)C19—C18—Cl2118.93 (13)
C8—C9—H9B110.6 (13)C17—C18—Cl2119.53 (13)
H9A—C9—H9B108.9 (19)C18—C19—C14119.48 (15)
C8—C9—H9C112.7 (14)C18—C19—H19121.8 (14)
H9A—C9—H9C107.3 (19)C14—C19—H19118.7 (14)
C6—C1—C2—C30.0 (2)C9—C8—C11—N−84.95 (15)
Cl1—C1—C2—C3179.99 (12)C3—C8—C11—O−85.57 (13)
C1—C2—C3—C40.0 (2)C10—C8—C11—O37.07 (17)
C1—C2—C3—C8175.66 (15)C9—C8—C11—O160.62 (12)
C2—C3—C4—N179.88 (14)C3—C8—C11—C12149.91 (14)
C8—C3—C4—N3.35 (17)C10—C8—C11—C12−87.45 (17)
C2—C3—C4—C50.2 (2)C9—C8—C11—C1236.10 (19)
C8—C3—C4—C5−176.36 (14)N—C11—O—C15102.17 (16)
N—C4—C5—C6179.99 (16)C12—C11—O—C15−20.53 (19)
C3—C4—C5—C6−0.4 (2)C8—C11—O—C15−148.14 (13)
C2—C1—C6—C5−0.2 (3)N—C11—C12—C13−104.55 (18)
Cl1—C1—C6—C5179.82 (13)O—C11—C12—C1317.6 (2)
C4—C5—C6—C10.4 (3)C8—C11—C12—C13138.45 (16)
C5—C4—N—C11−163.27 (16)C11—C12—C13—C14−5.4 (3)
C3—C4—N—C1117.04 (17)C12—C13—C14—C15−5.7 (2)
C5—C4—N—C7−11.2 (3)C12—C13—C14—C19177.48 (16)
C3—C4—N—C7169.10 (15)C11—O—C15—C16−172.39 (13)
C2—C3—C8—C1041.2 (2)C11—O—C15—C1411.3 (2)
C4—C3—C8—C10−142.78 (14)C19—C14—C15—O179.72 (14)
C2—C3—C8—C9−80.7 (2)C13—C14—C15—O2.8 (2)
C4—C3—C8—C995.37 (15)C19—C14—C15—C163.6 (2)
C2—C3—C8—C11163.81 (16)C13—C14—C15—C16−173.34 (14)
C4—C3—C8—C11−20.12 (15)O—C15—C16—C17−178.97 (14)
C4—N—C11—O81.89 (15)C14—C15—C16—C17−2.7 (2)
C7—N—C11—O−70.01 (18)C15—C16—C17—C180.2 (2)
C4—N—C11—C12−154.49 (13)C16—C17—C18—C191.4 (2)
C7—N—C11—C1253.62 (19)C16—C17—C18—Cl2−179.66 (12)
C4—N—C11—C8−29.08 (16)C17—C18—C19—C14−0.4 (2)
C7—N—C11—C8179.02 (14)Cl2—C18—C19—C14−179.39 (12)
C3—C8—C11—N28.87 (14)C15—C14—C19—C18−2.0 (2)
C10—C8—C11—N151.51 (13)C13—C14—C19—C18174.72 (15)

Table 2 Selected interplanar angles for the title compound

Atoms defining plane 1Atoms defining plane 2Interplanar angle (°)
C2, C6, C8, NC11, C19, O85.03 (4)
C3, C4, C8, NC8, C11, N28.9 (1)
C1, C2, C3, C4, C5, C6C3, C4, C8, N2.4 (1)

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: NC2106).

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