2′-Chloro-4-meth­oxy-3-nitro­benzil

Nithya, G.; Thanuja, B.; Chakkaravarthi, G.; Kanagam, C.C.

doi:10.1107/S1600536811019532

organic compounds

CRYSTALLOGRAPHIC
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ISSN: 2056-9890

Volume 67| Part 6| June 2011| Page o1535

doi:10.1107/S1600536811019532

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2′-Chloro-4-methoxy-3-nitrobenzil

G. Nithya,^a B. Thanuja,^a G. Chakkaravarthi ^b ^* and Charles C. Kanagam ^c

^aDepartment of Chemistry, Vels Univeristy, Pallavaram, Chennai 600 117, Tamil Nadu, India, ^bDepartment of Physics, CPCL Polytechnic College, Chennai 600 068, Tamil Nadu, India, and ^cDepartment of Chemistry, SRM Valliammai Engineering College, Kattankulathur 603 203, Tamil Nadu, India
^*Correspondence e-mail: chakkaravarthi_2005@yahoo.com

(Received 23 May 2011; accepted 23 May 2011; online 28 May 2011)

In the title compound, C₁₅H₁₀ClNO₅, the dihedral angle between the aromatic rings is 87.99 (5)°. The O—C—C—O torsion angle between the two carbonyl units is −119.03 (16)°. The crystal structure is stabilized by a weak intermolecular C—H⋯O hydrogen bond.

Related literature

For the biological activity of benzil derivatives, see: Mousset et al. (2008 ); Mahabusarakam et al. (2004 ); Ganapaty et al. (2009 ). For bond-length data and related structures, see: Allen et al. (1987 ); Fun & Kia (2008a ,b ).

Experimental

Crystal data

C₁₅H₁₀ClNO₅
M_r = 319.69
Triclinic, $[P \overline 1]$
a = 7.8559 (2) Å
b = 8.1003 (2) Å
c = 12.4961 (3) Å
α = 74.893 (1)°
β = 74.809 (2)°
γ = 68.593 (1)°
V = 702.32 (3) Å³
Z = 2
Mo Kα radiation
μ = 0.30 mm⁻¹
T = 295 K
0.30 × 0.20 × 0.20 mm

Data collection

Bruker Kappa APEXII diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ) T_min = 0.917, T_max = 0.943
17487 measured reflections
3937 independent reflections
3150 reflections with I > 2σ(I)
R_int = 0.021

Refinement

R[F² > 2σ(F²)] = 0.042
wR(F²) = 0.128
S = 1.06
3937 reflections
200 parameters
H-atom parameters constrained
Δρ_max = 0.48 e Å⁻³
Δρ_min = −0.41 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C3—H3⋯O2ⁱ	0.93	2.53	3.318 (2)	143
Symmetry code: (i) -x, -y+1, -z+2.

Data collection: APEX2 (Bruker, 2004 ); cell refinement: SAINT (Bruker, 2004); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009 ); software used to prepare material for publication: SHELXL97.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536811019532/bt5555sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536811019532/bt5555Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536811019532/bt5555Isup3.cml

checkCIF report

Comment top

Benzil derivates exhibit radical scavenging, antibacterial and hypertensive (Mahabusarakam et al., 2004), antiprotozoal (Ganapaty et al., 2009), antiproliferative and antimitotic (Mousset et al., 2008) activities.

The geometric parameters of the title compound (Fig. 1) agree with those in the reported structures (Fun & Kia, 2008a,b) and the literature values (Allen et al., 1987). The dihedral angle between the two rings is 87.99 (5)°. The mean plane of methoxy and nitro groups are twisted at an angle of 4.95 (8) and 32.19 (6)°, respectively, with the benzene ring (C9—C14).

The dicarbonyl unit has s-trans conformation as can be indicated by the torsion angles of O1–C7–C6–C1, and O2–C8–C9–C14 being -145.86 (16) and -171.77 (15)°, respectively. This conformation is authenticated by the torsion angle of O1–C7–C8–O2, being -119.03 (16)°.

The crystal structure exhibit weak C—H···O (Table 1 & Fig. 2) and π···π [Cg1···Cg1 (-x,1 - y,2 - z) distance of 3.8904 (9)Å and Cg2···Cg2 (1 - x,2 - y,1 - z) distance of 4.2891 (9) Å; Cg1 and Cg2 are the centroids of the rings (C1—C6) and (C9—C14), respectively] interactions.

Related literature top

For the biological activity of benzil derivatives, see: Mousset et al. (2008); Mahabusarakam et al. (2004); Ganapaty et al. (2009). For bond-length data and related structures, see: Allen et al. (1987); Fun & Kia (2008a,b).

Experimental top

The title compound was synthesized in two steps. The first step involves the benzoin condensation. 4 g of KCN was dissolved in 75cc of water in a one litre flask. To this was added 6.8 g (0.05 mole) of anisaldehyde, 7 g (0.05mole) of 2-chloro benzaldeyde and 75 cc of 95% ethanol. The mixture formed a solution at the boiling temperature and was refluxed for one and half hours. Steam was then passed through the solution until all the alcohol and nearly all the unchanged aldehyde were removed. The condensed water was decanted from the product and later set away to crystallize. The product was then pressed as free as possible from oily material on a suction funnel and washed with cold alcohol. In this way about 9 g of crude product was obtained. The crude mixture was dissolved in hot alcohol and allowed to crystallize slowly. The 2'chloro-4-methoxy benzoin crystallizes out as colourless, hexagonal crystals. From the benzoin about 1 gram was taken and treated with concentrated nitric acid by heating in a water bath inside a fume cupboard for about 3 h until it is free from the smell of nitrogen dioxide. It is then cooled and crystallized using hot ethanol. The obtained benzil is recrystallized using chloroform / acetone in the ratio 3:1. Pure crystals of benzil separates out. The yield is about 70–80%.

Computing details top

Data collection: APEX2 (Bruker, 2004); cell refinement: SAINT (Bruker, 2004); data reduction: SAINT (Bruker, 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top

Fig. 1. The molecular structure of the title compound, with atom labels and 30% probability displacement ellipsoids for non-H atoms.

1-(2-chlorophenyl)-2-(4-methoxy-3-nitrophenyl)ethane-1,2-dione top

Crystal data top

C₁₅H₁₀ClNO₅	Z = 2
M_r = 319.69	F(000) = 328
Triclinic, P1	D_x = 1.512 Mg m⁻³
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 7.8559 (2) Å	Cell parameters from 8570 reflections
b = 8.1003 (2) Å	θ = 2.7–29.0°
c = 12.4961 (3) Å	µ = 0.30 mm⁻¹
α = 74.893 (1)°	T = 295 K
β = 74.809 (2)°	Block, colourless
γ = 68.593 (1)°	0.30 × 0.20 × 0.20 mm
V = 702.32 (3) Å³

Data collection top

Bruker Kappa APEXII diffractometer	3937 independent reflections
Radiation source: fine-focus sealed tube	3150 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.021
ω and ϕ scans	θ_max = 29.6°, θ_min = 2.8°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −10→10
T_min = 0.917, T_max = 0.943	k = −11→10
17487 measured reflections	l = −12→17

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)] = 0.042	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.128	H-atom parameters constrained
S = 1.06	w = 1/[σ²(F_o²) + (0.0635P)² + 0.160P] where P = (F_o² + 2F_c²)/3
3937 reflections	(Δ/σ)_max < 0.001
200 parameters	Δρ_max = 0.48 e Å⁻³
0 restraints	Δρ_min = −0.41 e Å⁻³

Crystal data top

C₁₅H₁₀ClNO₅	γ = 68.593 (1)°
M_r = 319.69	V = 702.32 (3) Å³
Triclinic, P1	Z = 2
a = 7.8559 (2) Å	Mo Kα radiation
b = 8.1003 (2) Å	µ = 0.30 mm⁻¹
c = 12.4961 (3) Å	T = 295 K
α = 74.893 (1)°	0.30 × 0.20 × 0.20 mm
β = 74.809 (2)°

Data collection top

Bruker Kappa APEXII diffractometer	3937 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	3150 reflections with I > 2σ(I)
T_min = 0.917, T_max = 0.943	R_int = 0.021
17487 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.042	0 restraints
wR(F²) = 0.128	H-atom parameters constrained
S = 1.06	Δρ_max = 0.48 e Å⁻³
3937 reflections	Δρ_min = −0.41 e Å⁻³
200 parameters

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
Cl1	0.15981 (6)	0.62735 (6)	0.72481 (4)	0.06164 (15)
O1	0.66183 (15)	0.31713 (16)	0.83551 (11)	0.0568 (3)
O2	0.39794 (18)	0.70912 (17)	0.88704 (10)	0.0583 (3)
O3	0.82025 (17)	0.96590 (15)	0.40294 (9)	0.0523 (3)
O4	0.5354 (2)	1.23772 (19)	0.64274 (14)	0.0786 (5)
O5	0.7972 (2)	1.19529 (19)	0.52797 (13)	0.0714 (4)
N1	0.6714 (2)	1.14290 (17)	0.58676 (11)	0.0457 (3)
C1	0.17355 (19)	0.45206 (19)	0.83978 (12)	0.0404 (3)
C2	0.0214 (2)	0.3912 (2)	0.88416 (15)	0.0505 (4)
H2	−0.0877	0.4486	0.8552	0.061*
C3	0.0327 (2)	0.2455 (2)	0.97122 (17)	0.0571 (4)
H3	−0.0693	0.2046	1.0012	0.069*
C4	0.1931 (3)	0.1598 (2)	1.01429 (16)	0.0587 (4)
H4	0.1997	0.0611	1.0730	0.070*
C5	0.3451 (2)	0.2209 (2)	0.96994 (14)	0.0480 (3)
H5	0.4537	0.1627	0.9993	0.058*
C6	0.33717 (18)	0.36820 (18)	0.88208 (12)	0.0376 (3)
C7	0.50704 (19)	0.4244 (2)	0.83798 (12)	0.0402 (3)
C8	0.4875 (2)	0.6252 (2)	0.81244 (12)	0.0411 (3)
C9	0.59015 (19)	0.70248 (18)	0.70630 (12)	0.0384 (3)
C10	0.59340 (19)	0.87676 (18)	0.69408 (12)	0.0383 (3)
H10	0.5392	0.9386	0.7540	0.046*
C11	0.67654 (19)	0.95783 (17)	0.59376 (12)	0.0370 (3)
C12	0.7569 (2)	0.87131 (19)	0.50031 (12)	0.0397 (3)
C13	0.7560 (2)	0.6947 (2)	0.51480 (13)	0.0471 (3)
H13	0.8119	0.6315	0.4556	0.057*
C14	0.6734 (2)	0.61296 (19)	0.61536 (13)	0.0453 (3)
H14	0.6732	0.4958	0.6228	0.054*
C15	0.8938 (3)	0.8816 (3)	0.30568 (15)	0.0650 (5)
H15A	1.0008	0.7784	0.3192	0.098*
H15B	0.9292	0.9660	0.2416	0.098*
H15C	0.8008	0.8441	0.2911	0.098*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Cl1	0.0595 (3)	0.0632 (3)	0.0616 (3)	−0.0207 (2)	−0.0251 (2)	0.0054 (2)
O1	0.0354 (5)	0.0565 (7)	0.0711 (8)	−0.0172 (5)	−0.0089 (5)	0.0038 (6)
O2	0.0625 (7)	0.0654 (7)	0.0542 (7)	−0.0350 (6)	0.0107 (5)	−0.0236 (6)
O3	0.0677 (7)	0.0483 (6)	0.0396 (5)	−0.0255 (5)	0.0027 (5)	−0.0083 (4)
O4	0.0917 (11)	0.0534 (7)	0.0943 (11)	−0.0305 (7)	0.0123 (8)	−0.0384 (8)
O5	0.0858 (10)	0.0603 (8)	0.0791 (9)	−0.0483 (7)	0.0052 (7)	−0.0153 (7)
N1	0.0600 (8)	0.0395 (6)	0.0464 (7)	−0.0238 (6)	−0.0113 (6)	−0.0094 (5)
C1	0.0379 (7)	0.0413 (7)	0.0461 (7)	−0.0148 (6)	−0.0065 (5)	−0.0128 (6)
C2	0.0344 (7)	0.0574 (9)	0.0682 (10)	−0.0180 (6)	−0.0040 (7)	−0.0265 (8)
C3	0.0434 (8)	0.0594 (10)	0.0749 (11)	−0.0309 (7)	0.0117 (8)	−0.0246 (9)
C4	0.0578 (10)	0.0507 (9)	0.0641 (10)	−0.0294 (8)	0.0054 (8)	−0.0036 (8)
C5	0.0434 (7)	0.0443 (8)	0.0538 (9)	−0.0187 (6)	−0.0059 (6)	−0.0013 (6)
C6	0.0344 (6)	0.0384 (6)	0.0425 (7)	−0.0170 (5)	−0.0023 (5)	−0.0088 (5)
C7	0.0368 (7)	0.0461 (7)	0.0403 (7)	−0.0199 (6)	−0.0060 (5)	−0.0035 (6)
C8	0.0387 (7)	0.0463 (7)	0.0448 (7)	−0.0226 (6)	−0.0046 (6)	−0.0090 (6)
C9	0.0385 (6)	0.0377 (7)	0.0431 (7)	−0.0180 (5)	−0.0054 (5)	−0.0080 (5)
C10	0.0406 (7)	0.0397 (7)	0.0398 (7)	−0.0175 (6)	−0.0045 (5)	−0.0122 (5)
C11	0.0419 (7)	0.0333 (6)	0.0414 (7)	−0.0174 (5)	−0.0090 (5)	−0.0070 (5)
C12	0.0412 (7)	0.0403 (7)	0.0388 (7)	−0.0158 (6)	−0.0040 (5)	−0.0084 (5)
C13	0.0570 (9)	0.0404 (7)	0.0447 (8)	−0.0172 (7)	0.0010 (6)	−0.0173 (6)
C14	0.0535 (8)	0.0352 (7)	0.0510 (8)	−0.0191 (6)	−0.0041 (6)	−0.0126 (6)
C15	0.0772 (12)	0.0696 (11)	0.0423 (8)	−0.0258 (10)	0.0097 (8)	−0.0175 (8)

Geometric parameters (Å, º) top

Cl1—C1	1.7315 (16)	C5—H5	0.9300
O1—C7	1.2072 (18)	C6—C7	1.4894 (18)
O2—C8	1.2098 (18)	C7—C8	1.531 (2)
O3—C12	1.3379 (17)	C8—C9	1.4755 (19)
O3—C15	1.4329 (19)	C9—C10	1.3888 (18)
O4—N1	1.2288 (19)	C9—C14	1.392 (2)
O5—N1	1.2081 (18)	C10—C11	1.3727 (19)
N1—C11	1.4649 (17)	C10—H10	0.9300
C1—C2	1.386 (2)	C11—C12	1.4039 (19)
C1—C6	1.387 (2)	C12—C13	1.397 (2)
C2—C3	1.375 (3)	C13—C14	1.375 (2)
C2—H2	0.9300	C13—H13	0.9300
C3—C4	1.371 (3)	C14—H14	0.9300
C3—H3	0.9300	C15—H15A	0.9600
C4—C5	1.386 (2)	C15—H15B	0.9600
C4—H4	0.9300	C15—H15C	0.9600
C5—C6	1.390 (2)

C12—O3—C15	118.41 (13)	O2—C8—C7	116.30 (13)
O5—N1—O4	123.29 (13)	C9—C8—C7	120.11 (12)
O5—N1—C11	119.95 (13)	C10—C9—C14	118.62 (13)
O4—N1—C11	116.76 (13)	C10—C9—C8	118.39 (12)
C2—C1—C6	120.96 (14)	C14—C9—C8	122.86 (12)
C2—C1—Cl1	118.46 (12)	C11—C10—C9	120.09 (12)
C6—C1—Cl1	120.49 (11)	C11—C10—H10	120.0
C3—C2—C1	119.54 (15)	C9—C10—H10	120.0
C3—C2—H2	120.2	C10—C11—C12	122.04 (12)
C1—C2—H2	120.2	C10—C11—N1	116.88 (12)
C4—C3—C2	120.65 (14)	C12—C11—N1	121.04 (12)
C4—C3—H3	119.7	O3—C12—C13	124.79 (13)
C2—C3—H3	119.7	O3—C12—C11	118.04 (12)
C3—C4—C5	119.75 (16)	C13—C12—C11	117.09 (13)
C3—C4—H4	120.1	C14—C13—C12	120.92 (13)
C5—C4—H4	120.1	C14—C13—H13	119.5
C4—C5—C6	120.75 (16)	C12—C13—H13	119.5
C4—C5—H5	119.6	C13—C14—C9	121.19 (13)
C6—C5—H5	119.6	C13—C14—H14	119.4
C1—C6—C5	118.35 (12)	C9—C14—H14	119.4
C1—C6—C7	124.05 (13)	O3—C15—H15A	109.5
C5—C6—C7	117.59 (13)	O3—C15—H15B	109.5
O1—C7—C6	122.20 (13)	H15A—C15—H15B	109.5
O1—C7—C8	117.75 (12)	O3—C15—H15C	109.5
C6—C7—C8	119.31 (12)	H15A—C15—H15C	109.5
O2—C8—C9	123.30 (13)	H15B—C15—H15C	109.5

C6—C1—C2—C3	−0.1 (2)	O2—C8—C9—C14	−171.77 (15)
Cl1—C1—C2—C3	176.25 (12)	C7—C8—C9—C14	14.6 (2)
C1—C2—C3—C4	−0.1 (3)	C14—C9—C10—C11	0.4 (2)
C2—C3—C4—C5	0.2 (3)	C8—C9—C10—C11	−175.55 (13)
C3—C4—C5—C6	−0.1 (3)	C9—C10—C11—C12	1.3 (2)
C2—C1—C6—C5	0.3 (2)	C9—C10—C11—N1	178.94 (12)
Cl1—C1—C6—C5	−176.05 (11)	O5—N1—C11—C10	148.61 (15)
C2—C1—C6—C7	179.26 (13)	O4—N1—C11—C10	−31.4 (2)
Cl1—C1—C6—C7	3.0 (2)	O5—N1—C11—C12	−33.7 (2)
C4—C5—C6—C1	−0.2 (2)	O4—N1—C11—C12	146.30 (16)
C4—C5—C6—C7	−179.23 (15)	C15—O3—C12—C13	−0.3 (2)
C1—C6—C7—O1	−145.86 (16)	C15—O3—C12—C11	−176.86 (15)
C5—C6—C7—O1	33.2 (2)	C10—C11—C12—O3	174.20 (14)
C1—C6—C7—C8	44.2 (2)	N1—C11—C12—O3	−3.4 (2)
C5—C6—C7—C8	−136.81 (14)	C10—C11—C12—C13	−2.6 (2)
O1—C7—C8—O2	−119.03 (16)	N1—C11—C12—C13	179.86 (14)
C6—C7—C8—O2	51.37 (19)	O3—C12—C13—C14	−174.26 (15)
O1—C7—C8—C9	55.0 (2)	C11—C12—C13—C14	2.3 (2)
C6—C7—C8—C9	−134.60 (14)	C12—C13—C14—C9	−0.7 (3)
O2—C8—C9—C10	4.0 (2)	C10—C9—C14—C13	−0.6 (2)
C7—C8—C9—C10	−169.64 (13)	C8—C9—C14—C13	175.07 (15)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C3—H3···O2ⁱ	0.93	2.53	3.318 (2)	143

Symmetry code: (i) −x, −y+1, −z+2.

Experimental details

Crystal data
Chemical formula	C₁₅H₁₀ClNO₅
M_r	319.69
Crystal system, space group	Triclinic, P1
Temperature (K)	295
a, b, c (Å)	7.8559 (2), 8.1003 (2), 12.4961 (3)
α, β, γ (°)	74.893 (1), 74.809 (2), 68.593 (1)
V (Å³)	702.32 (3)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	0.30
Crystal size (mm)	0.30 × 0.20 × 0.20

Data collection
Diffractometer	Bruker Kappa APEXII diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 1996)
T_min, T_max	0.917, 0.943
No. of measured, independent and observed [I > 2σ(I)] reflections	17487, 3937, 3150
R_int	0.021
(sin θ/λ)_max (Å⁻¹)	0.696

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.042, 0.128, 1.06
No. of reflections	3937
No. of parameters	200
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.48, −0.41

Computer programs: APEX2 (Bruker, 2004), SAINT (Bruker, 2004), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C3—H3···O2ⁱ	0.93	2.53	3.318 (2)	143

Symmetry code: (i) −x, −y+1, −z+2.

Acknowledgements

GC acknowledges Vels University for providing laboratory facilities as well the opportunity to do the research work and members of the Chemistry Department of SRM Valliammai Engineering College for useful discussions.

References

Allen, F. H., Kennard, O., Watson, D. G., Brammer, L., Orpen, A. G. & Taylor, R. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1–19. CrossRef Web of Science Google Scholar
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