2′-Chloro-4-meth­oxy-3-nitro­benzil

G Nithya; B Thanuja; G Chakkaravarthi; Charles C Kanagam

doi:10.1107/S1600536811019532

. 2011 May 28;67(Pt 6):o1535. doi: 10.1107/S1600536811019532

2′-Chloro-4-methoxy-3-nitrobenzil

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

PMCID: PMC3120549 PMID: 21754895

Abstract

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,
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[F ² > 2σ(F ²)] = 0.042
wR(F ²) = 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

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.

Supplementary Material

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

e-67-o1535-sup1.cif^{(16.6KB, cif)}

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

e-67-o1535-Isup2.hkl^{(189KB, hkl)}

Supplementary material file. DOI: 10.1107/S1600536811019532/bt5555Isup3.cml

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

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

Open in a new tab

Symmetry code: (i) Inline graphic .

Acknowledgments

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.

supplementary crystallographic information

Comment

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.

Experimental

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%.