organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

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ISSN: 2056-9890

5-Chloro-1-(4-meth­­oxy­benz­yl)indoline-2,3-dione

aDepartment of Chemistry, Capital Normal University, Beijing 100048, People's Republic of China
*Correspondence e-mail: sl_cao@sohu.com

(Received 29 November 2010; accepted 16 December 2010; online 8 January 2011)

In the title compound, C16H12ClNO3, an arm-like 4-meth­oxy­benzene links to 5-chloro­indoline-2,3-dione through a methyl­ene group, with a dihedral angle between the mean planes of the benzene ring and the indole moiety of 88.44 (8)°. In the crystal, weak inter­molecular C—H⋯O and ππ stacking inter­actions [centroid–centroid distance = 3.383 (3) Å] link the mol­ecules together to form a three-dimensional framework.

Related literature

For the anti­tumor activity of N-benzyl isatin analogs, see: Vine et al. (2007[Vine, K. L., Locke, J. M., Ranson, M., Pyne, S. G. & Bremner, J. B. (2007). J. Med. Chem. 50, 5109-5117.]); Matesic et al. (2008[Matesic, L., Locke, J. M., Bremner, J. B., Pyne, S. G., Skropeta, D., Ranson, M. & Vine, K. L. (2008). Bioorg. Med. Chem. 16, 3118-3124.]); Penthala et al. (2010[Penthala, N. R., Yerramreddy, T. R., Madadi, N. R. & Crooks, P. A. (2010). Bioorg. Med. Chem. Lett. 20, 4468-4471.]). For the preparation of the title compound, see: Itoh et al. (2009[Itoh, T., Ishikawa, H. & Hayashi, Y. (2009). Org. Lett. 17, 3854-3857.]).

[Scheme 1]

Experimental

Crystal data
  • C16H12ClNO3

  • Mr = 301.72

  • Orthorhombic, P n a 21

  • a = 7.5318 (17) Å

  • b = 16.587 (4) Å

  • c = 11.220 (3) Å

  • V = 1401.7 (6) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.28 mm−1

  • T = 296 K

  • 0.30 × 0.22 × 0.10 mm

Data collection
  • Bruker APEXII CCD area-detector diffractometer

  • 7665 measured reflections

  • 3259 independent reflections

  • 2113 reflections with I > 2σ(I)

  • Rint = 0.029

Refinement
  • R[F2 > 2σ(F2)] = 0.040

  • wR(F2) = 0.091

  • S = 1.01

  • 3259 reflections

  • 190 parameters

  • 1 restraint

  • H-atom parameters constrained

  • Δρmax = 0.11 e Å−3

  • Δρmin = −0.14 e Å−3

  • Absolute structure: Flack (1983[Flack, H. D. (1983). Acta Cryst. A39, 876-881.]), 1514 Friedel pairs

  • Flack parameter: −0.01 (7)

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C16—H16C⋯O1i 0.96 2.63 3.537 (4) 159
C1—H1A⋯O2ii 0.93 2.58 3.391 (3) 146
Symmetry codes: (i) [-x+1, -y+1, z+{\script{1\over 2}}]; (ii) [-x+{\script{3\over 2}}, y+{\script{1\over 2}}, z+{\script{1\over 2}}].

Data collection: APEX2 (Bruker, 2007[Bruker (2007). APEX2, SADABS and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: APEX2 and SAINT (Bruker, 2007[Bruker (2007). APEX2, SADABS and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

Supporting information


Comment top

It has been reported that the introduction of a benzyl or naphthylmethyl group into the N1 position of isatin can significantly increase its cytotoxicity against a wide range of human tumor cell lines (Vine et al., 2007; Matesic et al., 2008; Penthala et al., 2010). The studies on the structure-activity relationship of these derivatives also revealed that the 4-methoxybenzyl is one of the most favorable groups for the enhancement of their relative cytotoxicity (Vine et al., 2007). To explore these isatin-based antitumor agents, we synthesized the title compound 5-chloro-1-(4-methoxybenzyl)-indoline-2,3-dione. Herein, we report the structure of the title compound.

In the title compound, C16H12ClNO3, the indoline and methoxybenzene moieties are linked by a methylene group with a C5—C7(methylene)-N1 angle of 113.86 (2)° (Fig. 1). The mean planes of the benzene ring and of the indole-2,3-dione exhibit a dihedral angle of 88.44 (8)°. The molecules stake along the a axis and interconnect through ππ interaction between the adjacent indole-2,3-dione moieties, forming a chain structure, as shown in Fig. 2. The distance between the two planes is 3.383 (3) Å. The parallel chains with the stacking molecules are further interconnected through two types of C—H···O(=C) ineractions: C—H(methyl)···O and C—H(benzene)···O (Table 1). The D···A distances vary from 3.391 (3) to 3.537 (4) Å, while the D—H···A angles lie within the 146–159° range. By these cooperative weak intermolecular interactions, a three-dimensional framework is constructed (Fig. 2).

Related literature top

For the antitumor activity of N-benzyl isatin analogs, see: Vine et al. (2007); Matesic et al. (2008); Penthala et al. (2010). For the preparation of the title compound, see: Itoh et al. (2009).

Experimental top

To an ice-bath cooled solution of 5-chloro-indoline-2,3-dione (0.36 g, 2 mmol) in N,N-dimethylformamide (20 ml) was added potassium carbonate (0.33 g, 2.4 mmol) and potassium iodide (0.07 g, 0.4 mmol) followed by 4-methoxybenzyl chloride (0.32 ml, 2.2 mmol). The reaction mixture was stirred at 110 °C for 3 h. After cooling to room temperature, the reaction mixture was poured into ice water (80 ml). The resulting precipitate was separated by filtration and purified by column chromatography on silica gel with dichloromethane as an eluent to give the title compound (Rf = 0.81, dichloromethane; m.p. 152–153 °C; yield 72%). The red crystals of the title compound were obtained by slow evaporation from the solution of dichloromethane/ethanol 8:2 (v/v) at room temperature.

Refinement top

All H atoms were discernible in the difference electron density maps. Nevertheless, the hydrogen atoms were placed into idealized positions and allowed to ride on the carrier atoms, with C—H = 0.93 and 0.97 Å [Uiso(H) = 1.2Ueq(C)] for aromatic and methylene H atoms, respectively, and with C—H = 0.96 Å [Uiso(H) = 1.5Ueq(C)] for methyl H atoms. The Flack parameter is -0.01 (7) in the non-centrosymmetric refinement (1514 Friedel pairs).

Computing details top

Data collection: APEX2 (Bruker, 2007); cell refinement: APEX2 and SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); 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) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. The title molecule with the atomic numbering scheme. The displacement ellipsoids are shown at the 30% probability level, while the hydrogen atoms are shown as rods of arbitrary radius.
[Figure 2] Fig. 2. View down the a axis of the packing structure of the title compound. The red dashed lines indicate the intermolecular C—H···O interactions, while the ππ stacking interactions are omitted for clarity. Symmetry codes: (i) x + 1/2, -y + 1/2, z; (ii) -x + 1, -y + 1, z - 1/2.
5-Chloro-1-(4-methoxybenzyl)indoline-2,3-dione top
Crystal data top
C16H12ClNO3Z = 4
Mr = 301.72F(000) = 624
Orthorhombic, Pna21Dx = 1.430 Mg m3
Dm = 1.430 Mg m3
Dm measured by not measured
Hall symbol: P 2c -2nMo Kα radiation, λ = 0.71073 Å
a = 7.5318 (17) ŵ = 0.28 mm1
b = 16.587 (4) ÅT = 296 K
c = 11.220 (3) ÅBlock, red
V = 1401.7 (6) Å30.30 × 0.22 × 0.10 mm
Data collection top
Bruker APEXII CCD area-detector
diffractometer
2113 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.029
Graphite monochromatorθmax = 27.9°, θmin = 2.2°
ϕ and ω scansh = 96
7665 measured reflectionsk = 2121
3259 independent reflectionsl = 1414
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.040H-atom parameters constrained
wR(F2) = 0.091 w = 1/[σ2(Fo2) + (0.0356P)2 + 0.0529P]
where P = (Fo2 + 2Fc2)/3
S = 1.01(Δ/σ)max < 0.001
3259 reflectionsΔρmax = 0.11 e Å3
190 parametersΔρmin = 0.14 e Å3
1 restraintAbsolute structure: Flack (1983), 1514 Friedel pairs
Primary atom site location: structure-invariant direct methodsAbsolute structure parameter: 0.01 (7)
Crystal data top
C16H12ClNO3V = 1401.7 (6) Å3
Mr = 301.72Z = 4
Orthorhombic, Pna21Mo Kα radiation
a = 7.5318 (17) ŵ = 0.28 mm1
b = 16.587 (4) ÅT = 296 K
c = 11.220 (3) Å0.30 × 0.22 × 0.10 mm
Data collection top
Bruker APEXII CCD area-detector
diffractometer
2113 reflections with I > 2σ(I)
7665 measured reflectionsRint = 0.029
3259 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.040H-atom parameters constrained
wR(F2) = 0.091Δρmax = 0.11 e Å3
S = 1.01Δρmin = 0.14 e Å3
3259 reflectionsAbsolute structure: Flack (1983), 1514 Friedel pairs
190 parametersAbsolute structure parameter: 0.01 (7)
1 restraint
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
Cl10.68342 (11)0.09999 (5)0.75885 (8)0.0978 (3)
O11.0165 (3)0.41051 (12)0.32537 (18)0.0858 (6)
O21.0012 (3)0.23283 (12)0.33272 (17)0.0861 (6)
O30.1766 (2)0.61539 (11)0.48186 (16)0.0694 (5)
N10.8772 (3)0.39659 (11)0.50677 (17)0.0571 (5)
C10.4538 (4)0.61020 (13)0.5928 (2)0.0611 (7)
H1A0.41970.65180.64350.073*
C20.3403 (3)0.58404 (13)0.5057 (2)0.0542 (6)
C30.3907 (3)0.52070 (13)0.4320 (2)0.0573 (6)
H3A0.31270.50140.37450.069*
C40.5565 (3)0.48649 (13)0.4443 (2)0.0545 (6)
H4A0.59030.44480.39370.065*
C50.6734 (3)0.51321 (13)0.5309 (2)0.0528 (6)
C60.6183 (4)0.57500 (13)0.6055 (2)0.0600 (6)
H6A0.69400.59300.66530.072*
C70.8599 (3)0.48135 (14)0.5399 (2)0.0656 (7)
H7A0.93620.51330.48870.079*
H7B0.90120.48810.62120.079*
C80.9424 (3)0.27675 (16)0.4091 (2)0.0619 (6)
C90.9526 (3)0.37002 (16)0.4045 (2)0.0624 (6)
C100.8176 (3)0.33139 (13)0.5770 (2)0.0489 (5)
C110.8551 (3)0.25832 (13)0.52206 (19)0.0515 (5)
C120.7381 (3)0.33395 (14)0.6865 (2)0.0585 (6)
H12A0.71280.38290.72320.070*
C130.6964 (3)0.26183 (16)0.7410 (2)0.0619 (6)
H13A0.64160.26210.81530.074*
C140.7354 (3)0.18880 (15)0.6861 (2)0.0611 (6)
C150.8143 (3)0.18620 (13)0.5764 (2)0.0588 (6)
H15A0.83960.13730.53970.071*
C160.1141 (4)0.67967 (17)0.5534 (3)0.0917 (10)
H16A0.00190.69560.52680.138*
H16B0.19390.72460.54700.138*
H16C0.10780.66250.63500.138*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl10.1025 (6)0.0832 (5)0.1078 (6)0.0071 (4)0.0163 (5)0.0446 (5)
O10.0912 (14)0.0996 (15)0.0667 (12)0.0161 (12)0.0144 (11)0.0145 (11)
O20.0987 (15)0.0962 (14)0.0634 (11)0.0152 (12)0.0085 (11)0.0211 (11)
O30.0674 (12)0.0639 (11)0.0768 (12)0.0064 (9)0.0015 (9)0.0028 (9)
N10.0626 (12)0.0543 (12)0.0542 (12)0.0024 (9)0.0045 (10)0.0012 (9)
C10.0826 (19)0.0469 (12)0.0538 (15)0.0005 (13)0.0015 (13)0.0052 (11)
C20.0622 (15)0.0478 (13)0.0528 (14)0.0045 (11)0.0026 (13)0.0042 (10)
C30.0680 (16)0.0484 (13)0.0555 (15)0.0070 (12)0.0092 (13)0.0014 (11)
C40.0656 (16)0.0463 (13)0.0516 (14)0.0069 (12)0.0003 (12)0.0040 (10)
C50.0626 (15)0.0420 (11)0.0536 (13)0.0073 (11)0.0012 (12)0.0035 (10)
C60.0775 (18)0.0508 (13)0.0515 (14)0.0073 (13)0.0070 (12)0.0052 (11)
C70.0719 (17)0.0473 (13)0.0775 (18)0.0101 (12)0.0107 (14)0.0034 (12)
C80.0628 (16)0.0724 (16)0.0504 (14)0.0086 (13)0.0054 (12)0.0097 (13)
C90.0605 (16)0.0754 (16)0.0513 (14)0.0047 (13)0.0019 (13)0.0033 (14)
C100.0485 (12)0.0515 (12)0.0468 (12)0.0001 (11)0.0045 (10)0.0013 (11)
C110.0510 (12)0.0551 (13)0.0482 (13)0.0033 (10)0.0085 (11)0.0051 (11)
C120.0649 (15)0.0583 (14)0.0522 (14)0.0016 (12)0.0009 (12)0.0101 (11)
C130.0601 (15)0.0795 (17)0.0460 (13)0.0036 (13)0.0033 (12)0.0020 (13)
C140.0565 (15)0.0637 (15)0.0630 (16)0.0028 (12)0.0136 (13)0.0138 (13)
C150.0588 (15)0.0506 (13)0.0669 (16)0.0049 (11)0.0166 (13)0.0035 (12)
C160.087 (2)0.088 (2)0.100 (2)0.0183 (17)0.0142 (18)0.0122 (18)
Geometric parameters (Å, º) top
Cl1—C141.729 (2)C6—H6A0.9300
O1—C91.213 (3)C7—H7A0.9700
O2—C81.208 (3)C7—H7B0.9700
O3—C21.364 (3)C8—C111.461 (3)
O3—C161.415 (3)C8—C91.550 (4)
N1—C91.354 (3)C10—C121.367 (3)
N1—C101.412 (3)C10—C111.389 (3)
N1—C71.460 (3)C11—C151.378 (3)
C1—C21.369 (3)C12—C131.380 (3)
C1—C61.378 (3)C12—H12A0.9300
C1—H1A0.9300C13—C141.391 (3)
C2—C31.390 (3)C13—H13A0.9300
C3—C41.379 (3)C14—C151.367 (4)
C3—H3A0.9300C15—H15A0.9300
C4—C51.384 (3)C16—H16A0.9600
C4—H4A0.9300C16—H16B0.9600
C5—C61.386 (3)C16—H16C0.9600
C5—C71.504 (3)
C2—O3—C16118.5 (2)O2—C8—C9124.1 (2)
C9—N1—C10110.92 (18)C11—C8—C9105.0 (2)
C9—N1—C7124.5 (2)O1—C9—N1127.4 (2)
C10—N1—C7124.6 (2)O1—C9—C8126.6 (2)
C2—C1—C6120.1 (2)N1—C9—C8106.1 (2)
C2—C1—H1A120.0C12—C10—C11121.0 (2)
C6—C1—H1A120.0C12—C10—N1128.1 (2)
O3—C2—C1125.7 (2)C11—C10—N1110.85 (19)
O3—C2—C3114.8 (2)C15—C11—C10121.0 (2)
C1—C2—C3119.6 (2)C15—C11—C8131.8 (2)
C4—C3—C2119.9 (2)C10—C11—C8107.1 (2)
C4—C3—H3A120.0C10—C12—C13118.1 (2)
C2—C3—H3A120.0C10—C12—H12A121.0
C3—C4—C5121.0 (2)C13—C12—H12A121.0
C3—C4—H4A119.5C12—C13—C14120.7 (2)
C5—C4—H4A119.5C12—C13—H13A119.6
C4—C5—C6118.1 (2)C14—C13—H13A119.6
C4—C5—C7121.9 (2)C15—C14—C13121.2 (2)
C6—C5—C7119.9 (2)C15—C14—Cl1119.8 (2)
C1—C6—C5121.3 (2)C13—C14—Cl1119.0 (2)
C1—C6—H6A119.3C14—C15—C11117.9 (2)
C5—C6—H6A119.3C14—C15—H15A121.0
N1—C7—C5113.85 (19)C11—C15—H15A121.0
N1—C7—H7A108.8O3—C16—H16A109.5
C5—C7—H7A108.8O3—C16—H16B109.5
N1—C7—H7B108.8H16A—C16—H16B109.5
C5—C7—H7B108.8O3—C16—H16C109.5
H7A—C7—H7B107.7H16A—C16—H16C109.5
O2—C8—C11130.8 (2)H16B—C16—H16C109.5
C16—O3—C2—C11.2 (3)C11—C8—C9—N10.1 (3)
C16—O3—C2—C3179.4 (2)C9—N1—C10—C12178.7 (2)
C6—C1—C2—O3178.0 (2)C7—N1—C10—C121.2 (4)
C6—C1—C2—C31.4 (3)C9—N1—C10—C110.7 (3)
O3—C2—C3—C4177.2 (2)C7—N1—C10—C11179.2 (2)
C1—C2—C3—C42.2 (3)C12—C10—C11—C150.4 (3)
C2—C3—C4—C51.3 (3)N1—C10—C11—C15177.8 (2)
C3—C4—C5—C60.5 (3)C12—C10—C11—C8178.8 (2)
C3—C4—C5—C7175.1 (2)N1—C10—C11—C80.6 (2)
C2—C1—C6—C50.4 (3)O2—C8—C11—C150.5 (5)
C4—C5—C6—C11.3 (3)C9—C8—C11—C15177.9 (2)
C7—C5—C6—C1174.4 (2)O2—C8—C11—C10178.7 (3)
C9—N1—C7—C5107.0 (3)C9—C8—C11—C100.3 (2)
C10—N1—C7—C573.1 (3)C11—C10—C12—C130.1 (3)
C4—C5—C7—N133.9 (3)N1—C10—C12—C13177.7 (2)
C6—C5—C7—N1150.6 (2)C10—C12—C13—C140.4 (3)
C10—N1—C9—O1179.9 (2)C12—C13—C14—C150.6 (4)
C7—N1—C9—O10.1 (4)C12—C13—C14—Cl1179.08 (19)
C10—N1—C9—C80.5 (3)C13—C14—C15—C110.4 (3)
C7—N1—C9—C8179.5 (2)Cl1—C14—C15—C11179.33 (18)
O2—C8—C9—O11.2 (4)C10—C11—C15—C140.1 (3)
C11—C8—C9—O1179.7 (2)C8—C11—C15—C14178.0 (2)
O2—C8—C9—N1178.4 (2)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C16—H16C···O1i0.962.633.537 (4)159
C1—H1A···O2ii0.932.583.391 (3)146
Symmetry codes: (i) x+1, y+1, z+1/2; (ii) x+3/2, y+1/2, z+1/2.

Experimental details

Crystal data
Chemical formulaC16H12ClNO3
Mr301.72
Crystal system, space groupOrthorhombic, Pna21
Temperature (K)296
a, b, c (Å)7.5318 (17), 16.587 (4), 11.220 (3)
V3)1401.7 (6)
Z4
Radiation typeMo Kα
µ (mm1)0.28
Crystal size (mm)0.30 × 0.22 × 0.10
Data collection
DiffractometerBruker APEXII CCD area-detector
diffractometer
Absorption correction
No. of measured, independent and
observed [I > 2σ(I)] reflections
7665, 3259, 2113
Rint0.029
(sin θ/λ)max1)0.658
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.040, 0.091, 1.01
No. of reflections3259
No. of parameters190
No. of restraints1
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.11, 0.14
Absolute structureFlack (1983), 1514 Friedel pairs
Absolute structure parameter0.01 (7)

Computer programs: APEX2 (Bruker, 2007), APEX2 and SAINT (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C16—H16C···O1i0.962.633.537 (4)159
C1—H1A···O2ii0.932.583.391 (3)146
Symmetry codes: (i) x+1, y+1, z+1/2; (ii) x+3/2, y+1/2, z+1/2.
 

Acknowledgements

This work was supported by the National Natural Science Foundation of China (project No. 20972099).

References

First citationBruker (2007). APEX2, SADABS and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.
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