organic compounds
1-Propyl-1H-indole-2,3-dione
aLaboratoire de Chimie Organique Appliquée-Chimie Appliquée, Faculté des Sciences et Techniques, Université Sidi Mohamed Ben Abdallah, Fès, Morocco, bLaboratoire de Chimie Organique Hétérocyclique, Pôle de Compétences Pharmacochimie, Mohammed V University in Rabat, BP 1014, Avenue Ibn Batouta, Rabat, Morocco, cUnité de Catalyse et de Chimie du Solide (UCCS), UMR 8181., Ecole Nationale Supérieure de Chimie de Lille, France, and dLaboratoire d'Ingénierie des Matériaux et d'Environnement, Modélisation et Application (LIMEMA), Ibn Tofail University, Kénitra, Morocco
*Correspondence e-mail: hafid.zouihri@gmail.com
In the title compound, C11H11NO2, the 1H-indole-2,3-dione unit is essentially planar, with an r.m.s. deviation of 0.0387 (13) Å. This plane makes a dihedral angle of 72.19 (17)° with the plane of the propyl substituent. In the crystal, chains propagating along the b axis are formed through C—H⋯O hydrogen bonds.
Keywords: crystal structure; indoline; hydrogen bonds.
CCDC reference: 1473515
Structure description
Formerly, the study of isatin (1H-indole-2,3-dione) derivatives was connected with dye synthesis, but more recently these heterocycles have been shown to possess biological and pharmacological properties. They are also used as key intermediates in organic synthesis (da Silva et al., 2001). Isatin is a core constituent of many (Batanero & Barba, 2006) and drugs (Aboul-Fadl et al., 2010) as well as dyes (Doménech et al., 2009), pesticides and analytical reagents. Various derivatives of isatin show diverse biological activities including antibacterial (Kassab et al., 2010), antifungal (Amal Raj et al., 2003), antiviral (Jarrahpour et al., 2007), anti-HIV (Bal et al., 2005), anti-mycobacterial (Karalı et al., 2007), anticancer (Gürsoy & Karalı 2003), and anti-inflammatory activities (Sridhar & Ramesh 2001) and are also effective anticonvulsants (Verma et al. 2004). Furthermore, isatin derivatives with their multifunctionality and diversity of transformations are synthetically versatile substrates and many efforts have been made toward the synthesis of these compounds.
In this work we report the synthesis and structure of a new derivative of isatin (Fig. 1) prepared by the action of 1-bromopropane alkyl on 1H-indole-2,3-dione in the presence of a catalytic quantity of tetra-n-butylammonium bromide. The near planarity of the isatin ring system is illustrated by a maximum deviation of 0.0387 (13) Å for the O2 atom from the best-fit plane through the 11 atoms of the ring system (Fig. 1). All bond lengths and angles compare well with those reported in the structure of 5-bromo-1-(prop-2-en-1-yl)-2, 3-dihydro-1H-indole-2, 3-dione (Maamri et al., 2012).
Two C—H⋯O intermolecular hydrogen bonds are observed in the ; they link molecules, forming parallel chains along the b axis (Figs. 2 and 3). π–π interactions are observed between the five- and six-membered rings of neighbouring molecules, with a Cg1⋯Cg2i distance of 3.6218 (10) Å [Cg1 and Cg2 are the centroids of the (N1/C1/C6–C8) and (C1–C6) rings, respectively; symmetry code: (i): 1 + x, y, z].
Table 1Synthesis and crystallization
To a solution of isatin (0.2 g, 1.4 mmol) dissolved in DMF(10 ml) was added potassium carbonate (0.33 g, 2.38 mmol), a catalytic quantity of tetra-n-butylammonium bromide (0.04 g, 0.11 mmol) and 1-bromopropane (0.13 ml, 1.4 mmol). The mixture was stirred for 48 h; the reaction was monitored by thin layer The mixture was filtered and the solvent removed under vacuum. The resulting solid was recrystallized from ethanol to afford the title compound as red crystals in 82% yield (m.p. 357 K).
Refinement
Crystal data, data collection and structure .
details are summarized in Table 2Structural data
CCDC reference: 1473515
10.1107/S241431461600609X/sj4024sup1.cif
contains datablock I. DOI:Structure factors: contains datablock I. DOI: 10.1107/S241431461600609X/sj4024Isup2.hkl
Supporting information file. DOI: 10.1107/S241431461600609X/sj4024Isup3.cml
To a solution of isatin (0.2g, 1.4mmol) dissolved in DMF(10ml) was added potassium carbonate (0.33g, 2.38 mmol), a catalytic quantity of tetra-n-butylammonium bromide (0.04g, 0.11mmol) and 1-bromopropane (0.13 ml, 1.4 mmol). The mixture was stirred for 48 h; the reaction was monitored by thin layer
The mixture was filtered and the solvent removed under vacuum. The resulting solid was recrystallized from ethanol to afford the title compound as red crystals in 82% yield (mp: 357°K)To a solution of isatin (0.2 g, 1.4 mmol) dissolved in DMF(10 ml) was added potassium carbonate (0.33 g, 2.38 mmol), a catalytic quantity of tetra-n-butylammonium bromide (0.04 g, 0.11 mmol) and 1-bromopropane (0.13 ml, 1.4 mmol). The mixture was stirred for 48 h; the reaction was monitored by thin layer
The mixture was filtered and the solvent removed under vacuum. The resulting solid was recrystallized from ethanol to afford the title compound as red crystals in 82% yield (m.p. 357 K)Formerly, the study of isatin (1H-indole-2,3-dione) derivatives was connected with dye synthesis, but more recently these heterocycles have been shown to possess biological and pharmacological properties. They are also used as key intermediates in organic synthesis (da Silva et al., 2001). Isatin is a core constituent of many
(Batanero & Barba, 2006) and drugs (Aboul-Fadl et al., 2010) as well as dyes (Doménech et al., 2009), pesticides and analytical reagents. Various derivatives of isatin show diverse biological activities including antibacterial (Kassab et al., 2010), antifungal (Amal Raj et al., 2003), antiviral (Jarrahpour et al., 2007), anti-HIV (Bal et al., 2005), anti-mycobacterial (Karalı et al., 2007), anticancer (Gürsoy & Karalı 2003), and anti-inflammatory activities (Sridhar & Ramesh 2001) and are also effective anticonvulsants (Verma et al. 2004). Furthermore, isatin derivatives with their multifunctionality and diversity of transformations are synthetically versatile substrates and many efforts have been made toward the synthesis of these compounds.In this work we report the synthesis and structure of a new derivative of isatin (Fig. 1) prepared by the action of 1-bromopropane alkyl on 1H-indole-2,3-dione in the presence of a catalytic quantity of tetra-n-butylammonium bromide. The near planarity of the isatin ring system is illustrated by a maximum deviation of 0.0387 (13) Å for the O2 atom from the best-fit plane through the 11 atoms of the ring system (Fig. 1). All bond lengths and angles compare well with those reported in the structure of 5-bromo-1-(prop-2-en-1-yl)-2, 3-dihydro-1H-indole-2, 3-dione (Maamri et al., 2012).
Three C—H···O intermolecular hydrogen bonds are observed in the π–π interactions are observed between the five- and six-membered rings of neighbouring molecules, with a Cg1···Cg2i distance of 3.6218 (10) Å [Cg1 and Cg2 are the centroids of the (C1, C6, N1, C8,C7) and (C1–C6) rings, respectively; symmetry code: (i): 1 + x, y, z].
Table 1; they link molecules, forming parallel chains along the b axis (Figs. 2 and 3).Data collection: APEX2 (Bruker, 2009); cell
SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXT (Sheldrick, 2015a); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015b); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: publCIF (Westrip, 2010).Fig. 1. The molecular structure of the title molecule, showing the atom-numbering scheme. Displacement ellipsoids are drawn at the 50% probability level. | |
Fig. 2. View along the a axis of the packing structure of the title compound. The dashed lines indicate intermolecular C—H···O interactions. | |
Fig. 3. The crystal structure of the title compound, viewed along the b axis, showing chains parallel to the b axis of the unit cell. |
C11H11NO2 | Dx = 1.329 Mg m−3 |
Mr = 189.21 | Mo Kα radiation, λ = 0.71073 Å |
Orthorhombic, P212121 | Cell parameters from 3897 reflections |
a = 4.4666 (2) Å | θ = 2.5–30.5° |
b = 12.9169 (6) Å | µ = 0.09 mm−1 |
c = 16.3857 (8) Å | T = 100 K |
V = 945.37 (8) Å3 | Parallelepiped, orange |
Z = 4 | 0.28 × 0.24 × 0.10 mm |
F(000) = 400 |
Bruker APEXII CCD diffractometer | 2720 independent reflections |
Radiation source: microfocus source | 2474 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.026 |
φ and ω scans | θmax = 30.5°, θmin = 2.0° |
Absorption correction: multi-scan (SADABS; Bruker, 2009) | h = −6→5 |
Tmin = 0.681, Tmax = 0.746 | k = −17→12 |
8372 measured reflections | l = −23→22 |
Refinement on F2 | Hydrogen site location: difference Fourier map |
Least-squares matrix: full | All H-atom parameters refined |
R[F2 > 2σ(F2)] = 0.038 | w = 1/[σ2(Fo2) + (0.043P)2] where P = (Fo2 + 2Fc2)/3 |
wR(F2) = 0.089 | (Δ/σ)max = 0.006 |
S = 1.25 | Δρmax = 0.23 e Å−3 |
2720 reflections | Δρmin = −0.21 e Å−3 |
171 parameters | Absolute structure: Flack x determined using 912 quotients [(I+)-(I-)]/[(I+)+(I-)] (Parsons et al., 2013) |
0 restraints | Absolute structure parameter: −0.5 (5) |
C11H11NO2 | V = 945.37 (8) Å3 |
Mr = 189.21 | Z = 4 |
Orthorhombic, P212121 | Mo Kα radiation |
a = 4.4666 (2) Å | µ = 0.09 mm−1 |
b = 12.9169 (6) Å | T = 100 K |
c = 16.3857 (8) Å | 0.28 × 0.24 × 0.10 mm |
Bruker APEXII CCD diffractometer | 2720 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 2009) | 2474 reflections with I > 2σ(I) |
Tmin = 0.681, Tmax = 0.746 | Rint = 0.026 |
8372 measured reflections |
R[F2 > 2σ(F2)] = 0.038 | All H-atom parameters refined |
wR(F2) = 0.089 | Δρmax = 0.23 e Å−3 |
S = 1.25 | Δρmin = −0.21 e Å−3 |
2720 reflections | Absolute structure: Flack x determined using 912 quotients [(I+)-(I-)]/[(I+)+(I-)] (Parsons et al., 2013) |
171 parameters | Absolute structure parameter: −0.5 (5) |
0 restraints |
Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes. |
x | y | z | Uiso*/Ueq | ||
C7 | 0.2074 (4) | 0.23633 (14) | 0.34207 (9) | 0.0167 (3) | |
C5 | 0.0195 (4) | 0.50779 (14) | 0.32062 (10) | 0.0161 (3) | |
C3 | −0.2671 (4) | 0.44800 (15) | 0.43838 (10) | 0.0200 (4) | |
C8 | 0.3971 (4) | 0.26930 (14) | 0.26673 (10) | 0.0167 (3) | |
C1 | 0.0449 (3) | 0.32977 (13) | 0.36607 (9) | 0.0145 (3) | |
C9 | 0.4709 (4) | 0.43360 (15) | 0.18883 (10) | 0.0173 (3) | |
C10 | 0.2755 (4) | 0.44538 (14) | 0.11315 (10) | 0.0179 (3) | |
C6 | 0.1282 (3) | 0.40851 (13) | 0.31200 (9) | 0.0131 (3) | |
C4 | −0.1806 (4) | 0.52562 (14) | 0.38456 (10) | 0.0194 (4) | |
C2 | −0.1525 (4) | 0.34886 (14) | 0.42971 (10) | 0.0166 (3) | |
C11 | 0.2039 (5) | 0.34352 (16) | 0.07157 (12) | 0.0270 (4) | |
N1 | 0.3325 (3) | 0.37085 (11) | 0.25297 (8) | 0.0150 (3) | |
O1 | 0.2111 (3) | 0.15078 (9) | 0.37136 (7) | 0.0235 (3) | |
O2 | 0.5712 (3) | 0.21478 (10) | 0.22898 (8) | 0.0247 (3) | |
H2 | −0.211 (5) | 0.2930 (18) | 0.4661 (14) | 0.030 (6)* | |
H3 | −0.405 (5) | 0.4602 (16) | 0.4792 (14) | 0.029 (5)* | |
H4 | −0.266 (5) | 0.5948 (17) | 0.3915 (12) | 0.022 (5)* | |
H5 | 0.075 (4) | 0.5642 (16) | 0.2856 (13) | 0.024 (5)* | |
H9A | 0.666 (4) | 0.3964 (15) | 0.1758 (12) | 0.016 (5)* | |
H9B | 0.517 (4) | 0.5007 (15) | 0.2124 (11) | 0.011 (4)* | |
H10B | 0.093 (5) | 0.4815 (16) | 0.1264 (12) | 0.023 (5)* | |
H10A | 0.391 (4) | 0.4923 (16) | 0.0746 (12) | 0.021 (5)* | |
H11A | 0.084 (6) | 0.3542 (16) | 0.0226 (15) | 0.034 (6)* | |
H11B | 0.387 (6) | 0.3080 (19) | 0.0530 (15) | 0.044 (7)* | |
H11C | 0.084 (5) | 0.2976 (17) | 0.1088 (15) | 0.031 (6)* |
U11 | U22 | U33 | U12 | U13 | U23 | |
C7 | 0.0205 (8) | 0.0129 (9) | 0.0166 (7) | −0.0014 (6) | −0.0032 (6) | −0.0009 (6) |
C5 | 0.0188 (7) | 0.0114 (9) | 0.0180 (7) | 0.0000 (6) | −0.0027 (6) | 0.0006 (6) |
C3 | 0.0184 (8) | 0.0257 (10) | 0.0158 (7) | 0.0029 (7) | 0.0011 (6) | −0.0029 (7) |
C8 | 0.0177 (7) | 0.0160 (9) | 0.0164 (7) | 0.0015 (6) | −0.0020 (6) | −0.0023 (6) |
C1 | 0.0160 (7) | 0.0123 (9) | 0.0151 (7) | −0.0012 (6) | −0.0030 (6) | 0.0007 (6) |
C9 | 0.0160 (7) | 0.0181 (10) | 0.0176 (7) | −0.0030 (7) | 0.0020 (6) | 0.0024 (6) |
C10 | 0.0189 (7) | 0.0180 (9) | 0.0170 (7) | −0.0001 (7) | 0.0004 (6) | 0.0017 (7) |
C6 | 0.0121 (6) | 0.0130 (9) | 0.0143 (6) | −0.0018 (6) | −0.0028 (6) | −0.0007 (6) |
C4 | 0.0208 (8) | 0.0159 (10) | 0.0217 (8) | 0.0042 (7) | −0.0034 (7) | −0.0033 (7) |
C2 | 0.0172 (7) | 0.0167 (9) | 0.0159 (7) | −0.0023 (6) | −0.0016 (6) | 0.0026 (6) |
C11 | 0.0354 (10) | 0.0226 (11) | 0.0231 (9) | 0.0029 (9) | −0.0061 (8) | −0.0039 (8) |
N1 | 0.0179 (7) | 0.0122 (8) | 0.0148 (6) | −0.0001 (5) | 0.0016 (5) | 0.0012 (5) |
O1 | 0.0353 (7) | 0.0104 (7) | 0.0247 (6) | 0.0001 (5) | −0.0025 (5) | 0.0032 (5) |
O2 | 0.0291 (7) | 0.0197 (8) | 0.0253 (6) | 0.0081 (6) | 0.0024 (6) | −0.0027 (5) |
C7—O1 | 1.205 (2) | C9—N1 | 1.464 (2) |
C7—C1 | 1.462 (2) | C9—C10 | 1.524 (2) |
C7—C8 | 1.557 (2) | C9—H9A | 1.02 (2) |
C5—C6 | 1.379 (2) | C9—H9B | 0.971 (19) |
C5—C4 | 1.396 (2) | C10—C11 | 1.516 (3) |
C5—H5 | 0.96 (2) | C10—H10B | 0.96 (2) |
C3—C2 | 1.386 (3) | C10—H10A | 1.02 (2) |
C3—C4 | 1.390 (3) | C6—N1 | 1.416 (2) |
C3—H3 | 0.92 (2) | C4—H4 | 0.98 (2) |
C8—O2 | 1.218 (2) | C2—H2 | 0.97 (2) |
C8—N1 | 1.362 (2) | C11—H11A | 0.97 (2) |
C1—C2 | 1.388 (2) | C11—H11B | 0.98 (3) |
C1—C6 | 1.399 (2) | C11—H11C | 1.01 (2) |
O1—C7—C1 | 131.04 (16) | C9—C10—H10B | 110.4 (12) |
O1—C7—C8 | 124.02 (16) | C11—C10—H10A | 110.2 (12) |
C1—C7—C8 | 104.93 (14) | C9—C10—H10A | 106.0 (11) |
C6—C5—C4 | 117.12 (16) | H10B—C10—H10A | 106.2 (17) |
C6—C5—H5 | 123.6 (12) | C5—C6—C1 | 121.17 (15) |
C4—C5—H5 | 119.3 (12) | C5—C6—N1 | 128.07 (14) |
C2—C3—C4 | 119.91 (16) | C1—C6—N1 | 110.75 (14) |
C2—C3—H3 | 118.6 (13) | C3—C4—C5 | 122.35 (17) |
C4—C3—H3 | 121.5 (13) | C3—C4—H4 | 118.5 (12) |
O2—C8—N1 | 127.46 (16) | C5—C4—H4 | 119.2 (12) |
O2—C8—C7 | 126.30 (16) | C1—C2—C3 | 118.41 (16) |
N1—C8—C7 | 106.23 (13) | C1—C2—H2 | 119.9 (13) |
C2—C1—C6 | 121.04 (16) | C3—C2—H2 | 121.7 (13) |
C2—C1—C7 | 131.62 (16) | C10—C11—H11A | 111.3 (12) |
C6—C1—C7 | 107.31 (14) | C10—C11—H11B | 111.7 (14) |
N1—C9—C10 | 113.42 (13) | H11A—C11—H11B | 105 (2) |
N1—C9—H9A | 104.5 (11) | C10—C11—H11C | 110.6 (13) |
C10—C9—H9A | 111.5 (11) | H11A—C11—H11C | 106.9 (19) |
N1—C9—H9B | 107.3 (11) | H11B—C11—H11C | 110.7 (19) |
C10—C9—H9B | 110.8 (11) | C8—N1—C6 | 110.75 (13) |
H9A—C9—H9B | 108.9 (15) | C8—N1—C9 | 124.24 (14) |
C11—C10—C9 | 113.57 (15) | C6—N1—C9 | 124.91 (14) |
C11—C10—H10B | 110.1 (12) | ||
O1—C7—C8—O2 | −0.7 (3) | C2—C3—C4—C5 | 0.3 (3) |
C1—C7—C8—O2 | 178.18 (16) | C6—C5—C4—C3 | 0.6 (2) |
O1—C7—C8—N1 | −179.65 (16) | C6—C1—C2—C3 | 0.3 (2) |
C1—C7—C8—N1 | −0.79 (17) | C7—C1—C2—C3 | 178.24 (17) |
O1—C7—C1—C2 | 0.4 (3) | C4—C3—C2—C1 | −0.8 (2) |
C8—C7—C1—C2 | −178.34 (16) | O2—C8—N1—C6 | −177.48 (16) |
O1—C7—C1—C6 | 178.56 (17) | C7—C8—N1—C6 | 1.48 (16) |
C8—C7—C1—C6 | −0.18 (17) | O2—C8—N1—C9 | −1.0 (3) |
N1—C9—C10—C11 | −61.1 (2) | C7—C8—N1—C9 | 177.95 (13) |
C4—C5—C6—C1 | −1.1 (2) | C5—C6—N1—C8 | 177.01 (16) |
C4—C5—C6—N1 | −179.70 (15) | C1—C6—N1—C8 | −1.69 (17) |
C2—C1—C6—C5 | 0.7 (2) | C5—C6—N1—C9 | 0.6 (2) |
C7—C1—C6—C5 | −177.72 (14) | C1—C6—N1—C9 | −178.13 (14) |
C2—C1—C6—N1 | 179.48 (14) | C10—C9—N1—C8 | 99.75 (18) |
C7—C1—C6—N1 | 1.09 (18) | C10—C9—N1—C6 | −84.27 (19) |
D—H···A | D—H | H···A | D···A | D—H···A |
C5—H5···O2i | 0.96 (2) | 2.52 (2) | 3.339 (2) | 143.6 (16) |
C9—H9A···O2 | 1.018 (18) | 2.538 (19) | 2.936 (2) | 102.8 (12) |
C10—H10B···O1ii | 0.96 (2) | 2.57 (2) | 3.439 (2) | 149.4 (17) |
Symmetry codes: (i) −x+1, y+1/2, −z+1/2; (ii) −x, y+1/2, −z+1/2. |
D—H···A | D—H | H···A | D···A | D—H···A |
C5—H5···O2i | 0.96 (2) | 2.52 (2) | 3.339 (2) | 143.6 (16) |
C9—H9A···O2 | 1.018 (18) | 2.538 (19) | 2.936 (2) | 102.8 (12) |
C10—H10B···O1ii | 0.96 (2) | 2.57 (2) | 3.439 (2) | 149.4 (17) |
Symmetry codes: (i) −x+1, y+1/2, −z+1/2; (ii) −x, y+1/2, −z+1/2. |
Experimental details
Crystal data | |
Chemical formula | C11H11NO2 |
Mr | 189.21 |
Crystal system, space group | Orthorhombic, P212121 |
Temperature (K) | 100 |
a, b, c (Å) | 4.4666 (2), 12.9169 (6), 16.3857 (8) |
V (Å3) | 945.37 (8) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.09 |
Crystal size (mm) | 0.28 × 0.24 × 0.10 |
Data collection | |
Diffractometer | Bruker APEXII CCD |
Absorption correction | Multi-scan (SADABS; Bruker, 2009) |
Tmin, Tmax | 0.681, 0.746 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 8372, 2720, 2474 |
Rint | 0.026 |
(sin θ/λ)max (Å−1) | 0.714 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.038, 0.089, 1.25 |
No. of reflections | 2720 |
No. of parameters | 171 |
H-atom treatment | All H-atom parameters refined |
Δρmax, Δρmin (e Å−3) | 0.23, −0.21 |
Absolute structure | Flack x determined using 912 quotients [(I+)-(I-)]/[(I+)+(I-)] (Parsons et al., 2013) |
Absolute structure parameter | −0.5 (5) |
Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXT (Sheldrick, 2015a), SHELXL2014 (Sheldrick, 2015b), PLATON (Spek, 2009), publCIF (Westrip, 2010).
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