supplementary materials


lh5180 scheme

Acta Cryst. (2011). E67, o98-o99    [ doi:10.1107/S160053681005049X ]

Ethyl 4-(1,3-dioxo-2,3-dihydro-1H-benzo[de]isoquinolin-2-yl)benzoate

Y. C. Chan, A. Salhin, M. Khairuddean, M. Hemamalini and H.-K. Fun

Abstract top

The title compound, C21H15NO4, was synthesized by reducing the Schiff base obtained from acenaphthenequinone and ethyl-4-aminobenzoate. The dihedral angle between the essentially planar 1,3-dioxo-2,3-dihydro-1H-benzo[de]isoquinoline ring system [maximum deviation = 0.061 (2) Å] and the benzene ring is 75.08 (10)°. In the crystal, molecules are connected via weak intermolecular C-H...O hydrogen bonds, forming a two-dimensional network. The ethyl group is disordered over two sets of sites with a refined occupancy ratio of 0.502 (12):0.498 (12).

Comment top

Acenaphthenequinone-based Schiff bases have been widely synthesized due to their significant applications in chemistry (Maldanis et al., 2002; Son et al., 2006), physics (Mhaidat et al., 2009) and pharmacology (Rodriguez-Argüelles et al., 1997; McDavid et al., 1951). As a continuation of the interest of our research group on the synthesis of Schiff base derivatives (Salhin et al., 2007, 2008, 2009; Tameem et al., 2006, 2007, 2008; Shalash et al., 2010), the title compound was prepared through the reduction of the Schiff base which was obtained from the condensation reaction of acenaphthenequinone and ethyl-4-aminobenzoate.

The molecular structure of the title compound is shown in Fig. 1. The 1,3-dioxo-1H-benzo[de]isoquinoline (O1–O2/N1/C1–C12) ring is approximately planar with maximum deviation of 0.061 (2) Å for atom N1. The ethyl group is disordered over two sites with a refined occupancy ratio of 0.502 (12):0.498 (12). The dihedral angle between the 1,3-dioxo-1H-benzo[de]isoquinoline (O1–O2/N1/C1–C12) ring and the benzene (C13–C18) ring is 75.08 (10)°.

In the crystal structure (Fig. 2), adjacent molecules are connected via intermolecular C7—H7A···O3i and C14—H14A···O1ii (Table 1) hydrogen bonds to form a two-dimensional network.

Related literature top

For details and applications of acenaphthenquinone Schiff bases, see: Maldanis et al. (2002); Son et al. (2006); Mhaidat et al. (2009); Rodriguez-Argüelles et al. (1997); McDavid et al. (1951); Salhin et al. (2007, 2008, 2009); Tameem et al. (2006, 2007, 2008); Shalash et al. (2010). For the stability of the temperature controller used in the data collection, see: Cosier & Glazer (1986).

Experimental top

A mixture of acenaphthenequinone (0.182 g, 1 mmol), ethyl-4-aminobenzoate (0.165 g, 1 mmol) and methanol (30 mL) was allowed to reflux for overnight. The synthesized Schiff base was then reduced using NaBH4 in ethanol with stirring at room temperature. Crystal of (I) suitable for X-ray crystallography was obtained by recrystallization from ethanol.

Refinement top

All H atoms were positioned geometrically [C–H = 0.93 or 0.96 Å] and were refined using a riding model, with Uiso(H) = 1.2 or 1.5 Ueq(C). The ethyl group disordered over two sites with a refined occupancy ratio of 0.502 (12):0.498 (12). Since there is no significant anomalous dispersion, 2242 Friedel pairs were merged before the final refinement. The larger than normal displacement parameter of O4 was noticed but it did not improve the precision of the structure to include this atom as a split atom in a disorder model.

Computing details top

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).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound, showing 30% probability displacement ellipsoids and the atom-numbering scheme. Dotted lines represents the disorder component.
[Figure 2] Fig. 2. The crystal packing of the title compound with hydrogen bonds shown as dashed lines.
Ethyl 4-(1,3-dioxo-2,3-dihydro-1H-benzo[de]isoquinolin-2-yl)benzoate top
Crystal data top
C21H15NO4F(000) = 720
Mr = 345.34Dx = 1.405 Mg m3
Monoclinic, CcMo Kα radiation, λ = 0.71073 Å
Hall symbol: C -2ycCell parameters from 5950 reflections
a = 5.2025 (7) Åθ = 2.5–30.0°
b = 18.066 (3) ŵ = 0.10 mm1
c = 17.560 (2) ÅT = 100 K
β = 98.365 (2)°Needle, colourless
V = 1632.8 (4) Å30.49 × 0.21 × 0.08 mm
Z = 4
Data collection top
Bruker APEXII DUO CCD area-detector
diffractometer
2393 independent reflections
Radiation source: fine-focus sealed tube2157 reflections with I > 2σ(I)
graphiteRint = 0.040
φ and ω scansθmax = 30.0°, θmin = 2.3°
Absorption correction: multi-scan
(SADABS; Bruker, 2009)
h = 77
Tmin = 0.953, Tmax = 0.992k = 2525
15726 measured reflectionsl = 2424
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)] = 0.065Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.171H-atom parameters constrained
S = 1.07 w = 1/[σ2(Fo2) + (0.0659P)2 + 3.4903P]
where P = (Fo2 + 2Fc2)/3
2393 reflections(Δ/σ)max < 0.001
256 parametersΔρmax = 0.56 e Å3
4 restraintsΔρmin = 0.38 e Å3
Crystal data top
C21H15NO4V = 1632.8 (4) Å3
Mr = 345.34Z = 4
Monoclinic, CcMo Kα radiation
a = 5.2025 (7) ŵ = 0.10 mm1
b = 18.066 (3) ÅT = 100 K
c = 17.560 (2) Å0.49 × 0.21 × 0.08 mm
β = 98.365 (2)°
Data collection top
Bruker APEXII DUO CCD area-detector
diffractometer
2393 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2009)
2157 reflections with I > 2σ(I)
Tmin = 0.953, Tmax = 0.992Rint = 0.040
15726 measured reflectionsθmax = 30.0°
Refinement top
R[F2 > 2σ(F2)] = 0.065H-atom parameters constrained
wR(F2) = 0.171Δρmax = 0.56 e Å3
S = 1.07Δρmin = 0.38 e Å3
2393 reflectionsAbsolute structure: ?
256 parametersFlack parameter: ?
4 restraintsRogers parameter: ?
Special details top

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 s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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 > 2σ(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*/UeqOcc. (<1)
O10.6572 (6)0.08698 (16)0.20848 (18)0.0348 (6)
O21.3670 (6)0.02019 (16)0.3453 (2)0.0378 (7)
O30.9558 (11)0.3058 (3)0.5083 (2)0.0746 (15)
O41.2949 (12)0.3339 (3)0.4533 (4)0.105 (2)
C10.7860 (7)0.0310 (2)0.2216 (2)0.0259 (7)
C20.7297 (7)0.0388 (2)0.1797 (2)0.0271 (7)
C30.5174 (8)0.0424 (2)0.1229 (2)0.0336 (8)
H3A0.41500.00070.11060.040*
C40.4555 (9)0.1099 (3)0.0835 (3)0.0386 (9)
H4A0.31170.11250.04530.046*
C50.6070 (8)0.1716 (2)0.1013 (2)0.0334 (8)
H5A0.56390.21580.07530.040*
C60.8256 (7)0.1689 (2)0.1583 (2)0.0293 (8)
C70.9882 (8)0.2308 (2)0.1776 (2)0.0332 (8)
H7A0.94770.27560.15270.040*
C81.2041 (9)0.2262 (2)0.2323 (3)0.0338 (8)
H8A1.30930.26740.24400.041*
C91.2662 (8)0.1586 (2)0.2707 (2)0.0293 (7)
H9A1.41410.15540.30730.035*
C101.1111 (7)0.09719 (19)0.2547 (2)0.0254 (7)
C110.8898 (7)0.1011 (2)0.1980 (2)0.0245 (7)
C121.1773 (7)0.0277 (2)0.2972 (2)0.0267 (7)
N11.0028 (6)0.03130 (17)0.27965 (19)0.0254 (6)
C131.0402 (7)0.0969 (2)0.3273 (2)0.0262 (7)
C141.2342 (7)0.1468 (2)0.3184 (2)0.0290 (7)
H14A1.34540.13820.28240.035*
C151.2614 (8)0.2100 (2)0.3639 (3)0.0345 (9)
H15A1.39170.24400.35870.041*
C161.0928 (9)0.2223 (2)0.4175 (2)0.0358 (9)
C170.9001 (8)0.1711 (3)0.4258 (2)0.0363 (9)
H17A0.78910.17930.46190.044*
C180.8716 (8)0.1078 (2)0.3807 (2)0.0322 (8)
H18A0.74240.07350.38610.039*
C191.1063 (12)0.2905 (3)0.4660 (3)0.0525 (14)
C201.244 (3)0.4000 (7)0.5078 (9)0.065 (4)0.493 (17)
H20A1.08100.42520.49060.078*0.493 (17)
H20B1.25090.38470.56100.078*0.493 (17)
C211.483 (3)0.4465 (6)0.4943 (9)0.066 (4)0.493 (17)
H21A1.49440.48960.52670.098*0.493 (17)
H21B1.46450.46150.44140.098*0.493 (17)
H21C1.63740.41730.50660.098*0.493 (17)
C20A1.343 (4)0.4184 (10)0.4745 (8)0.074 (5)0.507 (17)
H20C1.46220.44310.44520.088*0.507 (17)
H20D1.18540.44700.47490.088*0.507 (17)
C21A1.470 (3)0.3911 (11)0.5553 (10)0.103 (7)0.507 (17)
H21D1.49010.43220.59040.155*0.507 (17)
H21E1.63720.37010.55170.155*0.507 (17)
H21F1.36100.35430.57370.155*0.507 (17)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0360 (15)0.0291 (14)0.0376 (15)0.0107 (12)0.0006 (12)0.0021 (11)
O20.0347 (15)0.0267 (14)0.0483 (17)0.0047 (11)0.0064 (13)0.0026 (12)
O30.126 (4)0.056 (2)0.043 (2)0.035 (3)0.014 (2)0.0126 (18)
O40.102 (4)0.056 (3)0.152 (6)0.014 (3)0.003 (4)0.071 (3)
C10.0237 (15)0.0251 (17)0.0286 (17)0.0035 (12)0.0027 (13)0.0016 (13)
C20.0257 (16)0.0246 (17)0.0311 (18)0.0002 (13)0.0050 (14)0.0010 (13)
C30.0293 (19)0.034 (2)0.036 (2)0.0037 (15)0.0017 (16)0.0033 (16)
C40.034 (2)0.042 (2)0.037 (2)0.0004 (17)0.0010 (17)0.0098 (18)
C50.0343 (19)0.0318 (19)0.0340 (19)0.0042 (16)0.0048 (16)0.0082 (15)
C60.0308 (18)0.0262 (18)0.0315 (18)0.0034 (14)0.0069 (15)0.0025 (14)
C70.042 (2)0.0202 (16)0.039 (2)0.0004 (15)0.0101 (17)0.0030 (14)
C80.041 (2)0.0174 (16)0.043 (2)0.0069 (15)0.0071 (17)0.0006 (15)
C90.0309 (18)0.0197 (15)0.0367 (19)0.0027 (13)0.0023 (15)0.0004 (14)
C100.0268 (17)0.0191 (15)0.0306 (17)0.0019 (12)0.0053 (14)0.0026 (13)
C110.0241 (16)0.0217 (15)0.0283 (16)0.0006 (12)0.0054 (13)0.0006 (12)
C120.0269 (16)0.0202 (15)0.0324 (17)0.0021 (13)0.0024 (13)0.0033 (13)
N10.0261 (14)0.0195 (13)0.0302 (15)0.0014 (11)0.0028 (12)0.0017 (11)
C130.0255 (16)0.0226 (16)0.0295 (17)0.0059 (13)0.0008 (13)0.0019 (13)
C140.0282 (17)0.0219 (16)0.0370 (19)0.0033 (13)0.0052 (14)0.0028 (14)
C150.0288 (18)0.0224 (17)0.051 (2)0.0011 (14)0.0009 (17)0.0081 (16)
C160.041 (2)0.0303 (19)0.0328 (19)0.0131 (16)0.0068 (16)0.0080 (15)
C170.039 (2)0.041 (2)0.0277 (18)0.0122 (17)0.0023 (16)0.0033 (16)
C180.0335 (19)0.033 (2)0.0305 (18)0.0038 (15)0.0059 (15)0.0003 (15)
C190.075 (4)0.032 (2)0.044 (2)0.021 (2)0.013 (2)0.0114 (19)
C200.092 (11)0.041 (6)0.058 (8)0.012 (6)0.003 (7)0.022 (6)
C210.079 (9)0.033 (5)0.085 (10)0.031 (6)0.014 (8)0.014 (5)
C20A0.082 (12)0.074 (11)0.068 (9)0.014 (9)0.023 (8)0.015 (8)
C21A0.068 (11)0.102 (14)0.15 (2)0.012 (9)0.047 (12)0.023 (13)
Geometric parameters (Å, °) top
O1—C11.217 (5)C12—N11.405 (4)
O2—C121.210 (5)N1—C131.448 (5)
O3—C191.188 (7)C13—C141.379 (5)
O4—C191.300 (9)C13—C181.387 (5)
O4—C201.576 (14)C14—C151.389 (5)
O4—C20A1.581 (19)C14—H14A0.9300
C1—N11.406 (5)C15—C161.394 (6)
C1—C21.468 (5)C15—H15A0.9300
C2—C31.377 (5)C16—C171.387 (7)
C2—C111.410 (5)C16—C191.494 (6)
C3—C41.417 (6)C17—C181.386 (6)
C3—H3A0.9300C17—H17A0.9300
C4—C51.375 (6)C18—H18A0.9300
C4—H4A0.9300C20—C211.546 (10)
C5—C61.402 (6)C20—H20A0.9700
C5—H5A0.9300C20—H20B0.9700
C6—C71.415 (6)C21—H21A0.9600
C6—C111.424 (5)C21—H21B0.9600
C7—C81.370 (6)C21—H21C0.9600
C7—H7A0.9300C20A—C21A1.555 (10)
C8—C91.409 (5)C20A—H20C0.9700
C8—H8A0.9300C20A—H20D0.9700
C9—C101.376 (5)C21A—H21D0.9600
C9—H9A0.9300C21A—H21E0.9600
C10—C111.410 (5)C21A—H21F0.9600
C10—C121.476 (5)
C19—O4—C2098.9 (7)C1—N1—C13116.7 (3)
C19—O4—C20A129.7 (8)C14—C13—C18122.0 (4)
C20—O4—C20A33.0 (6)C14—C13—N1120.5 (3)
O1—C1—N1119.7 (3)C18—C13—N1117.5 (3)
O1—C1—C2123.7 (3)C13—C14—C15119.1 (4)
N1—C1—C2116.6 (3)C13—C14—H14A120.5
C3—C2—C11120.8 (3)C15—C14—H14A120.5
C3—C2—C1118.9 (3)C14—C15—C16119.9 (4)
C11—C2—C1120.2 (3)C14—C15—H15A120.1
C2—C3—C4119.7 (4)C16—C15—H15A120.1
C2—C3—H3A120.1C17—C16—C15120.0 (4)
C4—C3—H3A120.1C17—C16—C19117.7 (4)
C5—C4—C3120.3 (4)C15—C16—C19122.3 (5)
C5—C4—H4A119.8C18—C17—C16120.6 (4)
C3—C4—H4A119.8C18—C17—H17A119.7
C4—C5—C6120.8 (4)C16—C17—H17A119.7
C4—C5—H5A119.6C17—C18—C13118.5 (4)
C6—C5—H5A119.6C17—C18—H18A120.8
C5—C6—C7122.5 (4)C13—C18—H18A120.8
C5—C6—C11119.3 (3)O3—C19—O4123.3 (5)
C7—C6—C11118.2 (3)O3—C19—C16124.6 (6)
C8—C7—C6121.4 (4)O4—C19—C16112.0 (5)
C8—C7—H7A119.3C21—C20—O496.2 (9)
C6—C7—H7A119.3C21—C20—H20A112.5
C7—C8—C9119.7 (4)O4—C20—H20A112.5
C7—C8—H8A120.1C21—C20—H20B112.5
C9—C8—H8A120.1O4—C20—H20B112.5
C10—C9—C8121.0 (4)H20A—C20—H20B110.0
C10—C9—H9A119.5C21A—C20A—O486.6 (13)
C8—C9—H9A119.5C21A—C20A—H20C114.2
C9—C10—C11119.8 (3)O4—C20A—H20C114.2
C9—C10—C12119.7 (3)C21A—C20A—H20D114.2
C11—C10—C12120.4 (3)O4—C20A—H20D114.2
C2—C11—C10121.0 (3)H20C—C20A—H20D111.4
C2—C11—C6119.1 (3)C20A—C21A—H21D109.5
C10—C11—C6119.9 (3)C20A—C21A—H21E109.5
O2—C12—N1120.3 (3)H21D—C21A—H21E109.5
O2—C12—C10123.7 (3)C20A—C21A—H21F109.5
N1—C12—C10116.0 (3)H21D—C21A—H21F109.5
C12—N1—C1125.5 (3)H21E—C21A—H21F109.5
C12—N1—C13117.8 (3)
O1—C1—C2—C31.1 (6)C10—C12—N1—C15.3 (5)
N1—C1—C2—C3179.1 (4)O2—C12—N1—C137.6 (5)
O1—C1—C2—C11179.5 (4)C10—C12—N1—C13171.5 (3)
N1—C1—C2—C110.3 (5)O1—C1—N1—C12175.6 (4)
C11—C2—C3—C41.3 (6)C2—C1—N1—C124.3 (5)
C1—C2—C3—C4178.1 (4)O1—C1—N1—C137.6 (5)
C2—C3—C4—C50.3 (7)C2—C1—N1—C13172.6 (3)
C3—C4—C5—C60.4 (7)C12—N1—C13—C1476.6 (4)
C4—C5—C6—C7179.1 (4)C1—N1—C13—C14106.3 (4)
C4—C5—C6—C110.1 (6)C12—N1—C13—C18104.4 (4)
C5—C6—C7—C8178.5 (4)C1—N1—C13—C1872.7 (4)
C11—C6—C7—C80.8 (6)C18—C13—C14—C150.3 (6)
C6—C7—C8—C90.4 (6)N1—C13—C14—C15178.6 (3)
C7—C8—C9—C100.8 (6)C13—C14—C15—C160.2 (6)
C8—C9—C10—C111.4 (6)C14—C15—C16—C170.7 (6)
C8—C9—C10—C12178.5 (4)C14—C15—C16—C19177.7 (4)
C3—C2—C11—C10178.4 (4)C15—C16—C17—C180.6 (6)
C1—C2—C11—C102.2 (5)C19—C16—C17—C18177.9 (4)
C3—C2—C11—C61.6 (5)C16—C17—C18—C130.1 (6)
C1—C2—C11—C6177.8 (3)C14—C13—C18—C170.3 (6)
C9—C10—C11—C2179.0 (4)N1—C13—C18—C17178.6 (3)
C12—C10—C11—C21.1 (5)C20—O4—C19—O30.3 (10)
C9—C10—C11—C61.0 (5)C20A—O4—C19—O313.0 (13)
C12—C10—C11—C6179.0 (3)C20—O4—C19—C16176.7 (7)
C5—C6—C11—C20.8 (5)C20A—O4—C19—C16163.4 (9)
C7—C6—C11—C2179.9 (4)C17—C16—C19—O34.0 (7)
C5—C6—C11—C10179.1 (4)C15—C16—C19—O3174.4 (5)
C7—C6—C11—C100.2 (5)C17—C16—C19—O4179.7 (5)
C9—C10—C12—O21.7 (6)C15—C16—C19—O41.9 (7)
C11—C10—C12—O2178.4 (4)C19—O4—C20—C21176.4 (10)
C9—C10—C12—N1177.4 (3)C20A—O4—C20—C2122.5 (12)
C11—C10—C12—N12.5 (5)C19—O4—C20A—C21A84.2 (13)
O2—C12—N1—C1175.5 (4)C20—O4—C20A—C21A59.5 (14)
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
C7—H7A···O3i0.932.603.249 (4)127
C14—H14A···O1ii0.932.413.312 (3)165
Symmetry codes: (i) x, −y, z−1/2; (ii) x+1, y, z.
Table 1
Hydrogen-bond geometry (Å, °)
top
D—H···AD—HH···AD···AD—H···A
C7—H7A···O3i0.932.603.249 (4)127
C14—H14A···O1ii0.932.413.312 (3)165
Symmetry codes: (i) x, −y, z−1/2; (ii) x+1, y, z.
Acknowledgements top

YCC, AS and MK acknowledge financial support by the Universiti Sains Malaysia (USM) under the Science Fund Grant No. 1001/PKIMIA/823003. HKF and MH thank the Malaysian Government and Universiti Sains Malaysia for the Research University grant No. 1001/PFIZIK/811160. MH also thanks Universiti Sains Malaysia for a post-doctoral research fellowship.

references
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