2-[(E)-(2,4-Dichloro­benzyl­idene)amino]­isoindoline-1,3-dione

Asad, M.; Oo, C.-W.; Osman, H.; Hemamalini, M.; Fun, H.-K.

doi:10.1107/S1600536811023063

organic compounds

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ISSN: 2056-9890

Volume 67| Part 7| July 2011| Page o1712

doi:10.1107/S1600536811023063

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2-[(E)-(2,4-Dichlorobenzylidene)amino]isoindoline-1,3-dione

Mohammad Asad,^a Chuan-Wei Oo,^a ‡ Hasnah Osman,^a Madhukar Hemamalini ^b and Hoong-Kun Fun ^b ^*§

^aSchool of Chemical Sciences, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia, and ^bX-ray Crystallography Unit, School of Physics, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia
^*Correspondence e-mail: hkfun@usm.my

(Received 1 June 2011; accepted 14 June 2011; online 18 June 2011)

In the title compound, C₁₅H₈Cl₂N₂O₂, the molecule adopts an E configuration about the central C=N double bond. The isoindoline ring is essentially planar, with a maximum deviation of 0.019 (2) Å. The dihedral angle between the isoindoline ring and the dichloro-substituted benzene ring is 6.54 (9)°. An intramolecular C—H⋯O hydrogen bond occurs. A short Cl⋯Cl contact of 3.4027 (9) Å is present in the crystal structure. The crystal packing is further stabilized by weak C—H⋯π interactions.

Related literature

For the coordination ability and biological activity of Schiff bases, see: Bhunora et al. (2011 ); Gupta & Sutar (2008 ); Sridhar et al., (2001 ); Mladenova et al. (2002 ); Bharti et al. (2010 ); Tenorio et al. (2005 ); Liu et al. (1992 ); Hodnett & Dunn (1970 ).

Experimental

Crystal data

C₁₅H₈Cl₂N₂O₂
M_r = 319.13
Monoclinic, P 2₁ /c
a = 8.0387 (8) Å
b = 7.6981 (8) Å
c = 22.2686 (19) Å
β = 101.828 (3)°
V = 1348.8 (2) Å³
Z = 4
Mo Kα radiation
μ = 0.49 mm⁻¹
T = 296 K
0.44 × 0.19 × 0.15 mm

Data collection

Bruker APEXII DUO CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2009 ) T_min = 0.815, T_max = 0.930
13900 measured reflections
3902 independent reflections
2795 reflections with I > 2σ(I)
R_int = 0.033

Refinement

R[F² > 2σ(F²)] = 0.046
wR(F²) = 0.113
S = 1.07
3902 reflections
190 parameters
H-atom parameters constrained
Δρ_max = 0.30 e Å⁻³
Δρ_min = −0.42 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

Cg1 is the centroid of the C1–C6 ring.

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C7—H7A⋯O1	0.93	2.18	2.857 (2)	129
C2—H2A⋯Cg1ⁱ	0.93	2.81	3.663 (2)	153
Symmetry code: (i) $[-x+2, y-{\script{1\over 2}}, -z+{\script{3\over 2}}]$ .

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 ); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009 ).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536811023063/rz2609sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536811023063/rz2609Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536811023063/rz2609Isup3.cml

checkCIF report

Comment top

Schiff bases have been prepared from the condensation of aldehydes or ketones with amines and their coordination ability with metal ions such as copper (II), cobalt (II), iron (II) and zinc (II) (Bhunora et al., 2011; Gupta & Sutar, 2008) has been studied. Many Schiff bases have been reported to possess antibacterial (Sridhar et al.,, 2001; Mladenova et al., 2002); antifungal (Bharti et al., 2010; Tenorio et al., 2005); and antitumor activities (Liu et al., 1992; Hodnett & Dunn, 1970).

In the title compound (Fig. 1), the molecule adopts an E configuration about the central C7═N1 double bond. The isoindoline ring is essentially planar, with a maximum deviation of 0.019 (2) Å for atom C8. The dihedral angle between the isoindoline ring and the dichloro-substituted phenyl ring is 6.54 (9)°. An intramolecular C—H···O hydrogen bond which generates an S(6) ring motif and a short Cl···Cl contact of 3.4027 (9) Å are present in the crystal structure. The crystal packing (Fig. 2) is further stabilized by a weak C—H···π (Table 1) interactions involving the C1–C6 ring.

Related literature top

For the coordination ability and biological activity of Schiff bases, see: Bhunora et al. (2011); Gupta & Sutar (2008); Sridhar et al., (2001); Mladenova et al. (2002); Bharti et al. (2010); Tenorio et al. (2005); Liu et al. (1992); Hodnett & Dunn (1970).

Experimental top

A mixture of 2-amino-1,3-isoindolinedione (6.15 mmol, 1.0 g) and 2,4-dichloro benzaldehyde (6.15 mmol, 1.08 g) was dissolved in an appropriate amount of ethanol-glacial acetic acid (2:1 v/v). The mixture was refluxed on water-bath for 0.5 hr to give a white colour precipitate. The solution was cooled at room temperature, filtered off, washed with ethanol and dried. The isolated product was recrystallized from chloroform-methanol (1:1 v/v)to get the new Schiff base in 80% yield.

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

	Fig. 1. The asymmetric unit of the title compound, showing 30% probability displacement ellipsoids. The intramolecular C—H···O hydrogen bond is shown as a dashed line.
	Fig. 2. The crystal packing of the title compound viewed down the a axis. Hydrogen atoms are omitted for clarity.

2-[(E)-(2,4-Dichlorobenzylidene)amino]isoindoline-1,3-dione top

Crystal data top

C₁₅H₈Cl₂N₂O₂	F(000) = 648
M_r = 319.13	D_x = 1.572 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 4526 reflections
a = 8.0387 (8) Å	θ = 2.8–29.8°
b = 7.6981 (8) Å	µ = 0.49 mm⁻¹
c = 22.2686 (19) Å	T = 296 K
β = 101.828 (3)°	Block, colourless
V = 1348.8 (2) Å³	0.44 × 0.19 × 0.15 mm
Z = 4

Data collection top

Bruker APEXII DUO CCD area-detector diffractometer	3902 independent reflections
Radiation source: fine-focus sealed tube	2795 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.033
ϕ and ω scans	θ_max = 30.0°, θ_min = 1.9°
Absorption correction: multi-scan (SADABS; Bruker, 2009)	h = −10→11
T_min = 0.815, T_max = 0.930	k = −10→10
13900 measured reflections	l = −31→29

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.046	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.113	H-atom parameters constrained
S = 1.07	w = 1/[σ²(F_o²) + (0.0331P)² + 0.9203P] where P = (F_o² + 2F_c²)/3
3902 reflections	(Δ/σ)_max = 0.001
190 parameters	Δρ_max = 0.30 e Å⁻³
0 restraints	Δρ_min = −0.42 e Å⁻³

Crystal data top

C₁₅H₈Cl₂N₂O₂	V = 1348.8 (2) Å³
M_r = 319.13	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 8.0387 (8) Å	µ = 0.49 mm⁻¹
b = 7.6981 (8) Å	T = 296 K
c = 22.2686 (19) Å	0.44 × 0.19 × 0.15 mm
β = 101.828 (3)°

Data collection top

Bruker APEXII DUO CCD area-detector diffractometer	3902 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2009)	2795 reflections with I > 2σ(I)
T_min = 0.815, T_max = 0.930	R_int = 0.033
13900 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.046	0 restraints
wR(F²) = 0.113	H-atom parameters constrained
S = 1.07	Δρ_max = 0.30 e Å⁻³
3902 reflections	Δρ_min = −0.42 e Å⁻³
190 parameters

Special details top

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.

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 > 2sigma(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

	x	y	z	U_iso*/U_eq
Cl1	0.72877 (6)	−0.18254 (8)	0.79982 (3)	0.05067 (17)
Cl2	1.31606 (7)	−0.18842 (9)	0.72366 (3)	0.05889 (19)
O1	0.58896 (19)	0.1209 (2)	0.93934 (8)	0.0566 (5)
O2	1.08478 (17)	0.3584 (2)	1.04839 (7)	0.0457 (4)
N1	0.9657 (2)	0.1599 (2)	0.94538 (8)	0.0374 (4)
N2	0.86224 (19)	0.2180 (2)	0.98379 (7)	0.0347 (4)
C1	0.9387 (2)	−0.1149 (3)	0.81141 (9)	0.0337 (4)
C2	1.0327 (2)	−0.1710 (3)	0.76903 (9)	0.0366 (4)
H2A	0.9837	−0.2409	0.7361	0.044*
C3	1.2005 (2)	−0.1199 (3)	0.77727 (9)	0.0369 (4)
C4	1.2766 (2)	−0.0181 (3)	0.82651 (9)	0.0387 (4)
H4A	1.3906	0.0127	0.8319	0.046*
C5	1.1798 (2)	0.0371 (3)	0.86757 (9)	0.0367 (4)
H5A	1.2299	0.1064	0.9005	0.044*
C6	1.0085 (2)	−0.0087 (3)	0.86084 (8)	0.0330 (4)
C7	0.9041 (2)	0.0526 (3)	0.90345 (9)	0.0378 (4)
H7A	0.7932	0.0130	0.8997	0.045*
C8	0.6843 (2)	0.2004 (3)	0.97890 (9)	0.0366 (4)
C9	0.6452 (2)	0.3000 (3)	1.03100 (9)	0.0339 (4)
C10	0.4911 (3)	0.3240 (3)	1.04859 (10)	0.0413 (5)
H10A	0.3918	0.2728	1.0271	0.050*
C11	0.4911 (3)	0.4273 (3)	1.09946 (10)	0.0449 (5)
H11A	0.3897	0.4458	1.1125	0.054*
C12	0.6395 (3)	0.5040 (3)	1.13147 (10)	0.0491 (5)
H12A	0.6356	0.5733	1.1654	0.059*
C13	0.7941 (3)	0.4787 (3)	1.11370 (9)	0.0436 (5)
H13A	0.8937	0.5295	1.1351	0.052*
C14	0.7933 (2)	0.3755 (3)	1.06312 (9)	0.0336 (4)
C15	0.9360 (2)	0.3247 (3)	1.03399 (9)	0.0338 (4)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Cl1	0.0330 (2)	0.0650 (4)	0.0558 (3)	−0.0135 (2)	0.0131 (2)	−0.0105 (3)
Cl2	0.0444 (3)	0.0766 (5)	0.0621 (4)	−0.0071 (3)	0.0259 (3)	−0.0224 (3)
O1	0.0355 (8)	0.0710 (12)	0.0616 (10)	−0.0063 (8)	0.0057 (7)	−0.0274 (9)
O2	0.0290 (7)	0.0587 (10)	0.0490 (9)	−0.0036 (7)	0.0069 (6)	−0.0061 (7)
N1	0.0326 (8)	0.0425 (10)	0.0388 (9)	0.0032 (7)	0.0114 (7)	−0.0030 (7)
N2	0.0294 (7)	0.0386 (9)	0.0368 (8)	0.0007 (7)	0.0082 (6)	−0.0035 (7)
C1	0.0275 (8)	0.0357 (10)	0.0377 (10)	−0.0017 (7)	0.0060 (7)	0.0023 (8)
C2	0.0338 (9)	0.0388 (11)	0.0370 (10)	−0.0015 (8)	0.0066 (8)	−0.0031 (9)
C3	0.0322 (9)	0.0411 (11)	0.0394 (10)	0.0022 (8)	0.0123 (8)	−0.0018 (9)
C4	0.0279 (9)	0.0432 (12)	0.0446 (11)	−0.0031 (8)	0.0068 (8)	−0.0020 (9)
C5	0.0336 (9)	0.0387 (11)	0.0364 (10)	−0.0007 (8)	0.0036 (7)	−0.0033 (8)
C6	0.0319 (9)	0.0342 (10)	0.0331 (9)	0.0018 (8)	0.0071 (7)	0.0024 (8)
C7	0.0329 (9)	0.0434 (12)	0.0383 (10)	0.0007 (8)	0.0101 (8)	−0.0014 (9)
C8	0.0293 (9)	0.0395 (11)	0.0408 (10)	0.0015 (8)	0.0065 (8)	−0.0010 (9)
C9	0.0301 (9)	0.0350 (11)	0.0373 (10)	0.0013 (8)	0.0082 (7)	0.0027 (8)
C10	0.0322 (9)	0.0433 (12)	0.0499 (12)	−0.0011 (9)	0.0116 (8)	0.0036 (10)
C11	0.0407 (11)	0.0473 (13)	0.0517 (12)	0.0051 (9)	0.0216 (9)	0.0036 (10)
C12	0.0541 (13)	0.0529 (14)	0.0445 (12)	0.0032 (11)	0.0198 (10)	−0.0054 (10)
C13	0.0411 (11)	0.0498 (13)	0.0401 (11)	−0.0012 (10)	0.0084 (8)	−0.0066 (10)
C14	0.0309 (9)	0.0348 (10)	0.0354 (9)	0.0017 (8)	0.0077 (7)	0.0029 (8)
C15	0.0295 (8)	0.0372 (11)	0.0348 (9)	−0.0003 (8)	0.0071 (7)	0.0015 (8)

Geometric parameters (Å, º) top

Cl1—C1	1.7338 (19)	C5—H5A	0.9300
Cl2—C3	1.7383 (19)	C6—C7	1.467 (3)
O1—C8	1.209 (2)	C7—H7A	0.9300
O2—C15	1.201 (2)	C8—C9	1.477 (3)
N1—C7	1.268 (3)	C9—C14	1.385 (3)
N1—N2	1.384 (2)	C9—C10	1.386 (3)
N2—C15	1.416 (3)	C10—C11	1.384 (3)
N2—C8	1.419 (2)	C10—H10A	0.9300
C1—C2	1.393 (3)	C11—C12	1.390 (3)
C1—C6	1.393 (3)	C11—H11A	0.9300
C2—C3	1.381 (3)	C12—C13	1.393 (3)
C2—H2A	0.9300	C12—H12A	0.9300
C3—C4	1.384 (3)	C13—C14	1.377 (3)
C4—C5	1.384 (3)	C13—H13A	0.9300
C4—H4A	0.9300	C14—C15	1.482 (3)
C5—C6	1.399 (3)

C7—N1—N2	118.18 (16)	O1—C8—N2	125.65 (18)
N1—N2—C15	117.91 (15)	O1—C8—C9	129.07 (18)
N1—N2—C8	130.24 (16)	N2—C8—C9	105.28 (16)
C15—N2—C8	111.63 (15)	C14—C9—C10	121.44 (19)
C2—C1—C6	122.02 (17)	C14—C9—C8	108.96 (16)
C2—C1—Cl1	116.91 (15)	C10—C9—C8	129.59 (19)
C6—C1—Cl1	121.07 (15)	C11—C10—C9	117.2 (2)
C3—C2—C1	118.21 (18)	C11—C10—H10A	121.4
C3—C2—H2A	120.9	C9—C10—H10A	121.4
C1—C2—H2A	120.9	C10—C11—C12	121.30 (19)
C2—C3—C4	121.86 (18)	C10—C11—H11A	119.3
C2—C3—Cl2	117.88 (16)	C12—C11—H11A	119.3
C4—C3—Cl2	120.26 (15)	C11—C12—C13	121.2 (2)
C5—C4—C3	118.67 (18)	C11—C12—H12A	119.4
C5—C4—H4A	120.7	C13—C12—H12A	119.4
C3—C4—H4A	120.7	C14—C13—C12	117.3 (2)
C4—C5—C6	121.77 (18)	C14—C13—H13A	121.4
C4—C5—H5A	119.1	C12—C13—H13A	121.4
C6—C5—H5A	119.1	C13—C14—C9	121.60 (18)
C1—C6—C5	117.44 (17)	C13—C14—C15	129.51 (18)
C1—C6—C7	120.55 (17)	C9—C14—C15	108.90 (17)
C5—C6—C7	122.01 (18)	O2—C15—N2	124.69 (17)
N1—C7—C6	119.80 (18)	O2—C15—C14	130.08 (19)
N1—C7—H7A	120.1	N2—C15—C14	105.21 (15)
C6—C7—H7A	120.1

C7—N1—N2—C15	174.19 (18)	N2—C8—C9—C14	1.7 (2)
C7—N1—N2—C8	−11.8 (3)	O1—C8—C9—C10	1.8 (4)
C6—C1—C2—C3	0.6 (3)	N2—C8—C9—C10	−178.9 (2)
Cl1—C1—C2—C3	−179.66 (16)	C14—C9—C10—C11	0.3 (3)
C1—C2—C3—C4	1.0 (3)	C8—C9—C10—C11	−179.0 (2)
C1—C2—C3—Cl2	−179.27 (16)	C9—C10—C11—C12	0.1 (3)
C2—C3—C4—C5	−1.6 (3)	C10—C11—C12—C13	−0.4 (4)
Cl2—C3—C4—C5	178.68 (17)	C11—C12—C13—C14	0.2 (4)
C3—C4—C5—C6	0.6 (3)	C12—C13—C14—C9	0.2 (3)
C2—C1—C6—C5	−1.5 (3)	C12—C13—C14—C15	−179.5 (2)
Cl1—C1—C6—C5	178.73 (15)	C10—C9—C14—C13	−0.5 (3)
C2—C1—C6—C7	177.96 (19)	C8—C9—C14—C13	178.99 (19)
Cl1—C1—C6—C7	−1.8 (3)	C10—C9—C14—C15	179.29 (19)
C4—C5—C6—C1	0.9 (3)	C8—C9—C14—C15	−1.3 (2)
C4—C5—C6—C7	−178.58 (19)	N1—N2—C15—O2	−5.7 (3)
N2—N1—C7—C6	178.49 (17)	C8—N2—C15—O2	179.2 (2)
C1—C6—C7—N1	−174.55 (19)	N1—N2—C15—C14	175.94 (16)
C5—C6—C7—N1	4.9 (3)	C8—N2—C15—C14	0.8 (2)
N1—N2—C8—O1	3.4 (4)	C13—C14—C15—O2	1.8 (4)
C15—N2—C8—O1	177.8 (2)	C9—C14—C15—O2	−177.9 (2)
N1—N2—C8—C9	−175.91 (19)	C13—C14—C15—N2	−180.0 (2)
C15—N2—C8—C9	−1.6 (2)	C9—C14—C15—N2	0.3 (2)
O1—C8—C9—C14	−177.6 (2)

Hydrogen-bond geometry (Å, º) top

Cg1 is the centroid of the C1–C6 ring.

D—H···A	D—H	H···A	D···A	D—H···A
C7—H7A···O1	0.93	2.18	2.857 (2)	129
C2—H2A···Cg1ⁱ	0.93	2.81	3.663 (2)	153

Symmetry code: (i) −x+2, y−1/2, −z+3/2.

Experimental details

Crystal data
Chemical formula	C₁₅H₈Cl₂N₂O₂
M_r	319.13
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	296
a, b, c (Å)	8.0387 (8), 7.6981 (8), 22.2686 (19)
β (°)	101.828 (3)
V (Å³)	1348.8 (2)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.49
Crystal size (mm)	0.44 × 0.19 × 0.15

Data collection
Diffractometer	Bruker APEXII DUO CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2009)
T_min, T_max	0.815, 0.930
No. of measured, independent and observed [I > 2σ(I)] reflections	13900, 3902, 2795
R_int	0.033
(sin θ/λ)_max (Å⁻¹)	0.704

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.046, 0.113, 1.07
No. of reflections	3902
No. of parameters	190
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.30, −0.42

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

Hydrogen-bond geometry (Å, º) top

Cg1 is the centroid of the C1–C6 ring.

D—H···A	D—H	H···A	D···A	D—H···A
C7—H7A···O1	0.93	2.18	2.857 (2)	129
C2—H2A···Cg1ⁱ	0.93	2.81	3.663 (2)	153

Symmetry code: (i) −x+2, y−1/2, −z+3/2.

Footnotes

‡Additional correspondence author, e-mail: oocw@usm.my.

§Thomson Reuters ResearcherID: A-3561-2009.

Acknowledgements

MA, CWO and HO thank Universiti Sains Malaysia (USM) for providing the necessary research facilities and RU research funding under grant No. 1001/PKIMIA/811134. MA also thanks USM for the award of a post-doctoral fellowship. HKF and MH thank the Malaysian Government and USM for the Research University Grant No. 1001/PFIZIK/811160. MH also thanks Universiti Sains Malaysia for a post-doctoral research fellowship.

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