Bis(2-nitro­phen­yl)methane

Daron E Janzen; Laura E Crepeau; Benjamin D Hageseth; James W Wollack

doi:10.1107/S1600536814015438

. 2014 Jul 5;70(Pt 8):o859. doi: 10.1107/S1600536814015438

Bis(2-nitrophenyl)methane

Daron E Janzen ^a,^*, Laura E Crepeau ^a, Benjamin D Hageseth ^a, James W Wollack ^a

PMCID: PMC4158535 PMID: 25249909

Abstract

In the title compound, C₁₃H₁₀N₂O₄, the nitro groups are twisted significantly relative to the benzene rings [dihedral angles = 16.64 (18) and 28.02 (11)°]. The benzene groups are nearly perpendicular to each other [dihedral angle = 87.72 (6)°]. Short intermolecular N⋯O and C⋯O [2.981 (2) and 3.060 (2) Å, respectively] contacts suggest possible weak π-interactions between nitro groups and between benzene and nitro groups. In addition, there are π–π interactions between one benzene group and an inversion-related equivalent [interplanar separation = 3.494 (2) Å].

Keywords: crystal structure

Related literature

The synthesis of the title compound has been previously reported (Allinger & Youngdale, 1962 ▶), although by different methods from the preparation of the sample used for this study [a modification of the method given by Lu et al. (2006 ▶)]. For related structures, see: Barnes et al. (1981 ▶); Brito et al. (2007 ▶); Cousson et al. (1993 ▶); Housty (1961 ▶).

Experimental

Crystal data

C₁₃H₁₀N₂O₄
M _r = 258.23
Triclinic,
a = 7.628 (3) Å
b = 8.340 (3) Å
c = 9.464 (4) Å
α = 103.544 (8)°
β = 92.555 (7)°
γ = 94.870 (7)°
V = 582.0 (4) Å³
Z = 2
Mo Kα radiation
μ = 0.11 mm⁻¹
T = 173 K
0.17 × 0.15 × 0.10 mm

Data collection

Rigaku XtaLAB mini diffractometer
Absorption correction: multi-scan (REQAB; Rigaku, 1998 ▶) T _min = 0.735, T _max = 0.989
6052 measured reflections
2648 independent reflections
1866 reflections with F ² > 2σ(F ²)
R _int = 0.038

Refinement

R[F ² > 2σ(F ²)] = 0.048
wR(F ²) = 0.114
S = 1.02
2648 reflections
172 parameters
H-atom parameters constrained
Δρ_max = 0.19 e Å⁻³
Δρ_min = −0.23 e Å⁻³

Data collection: CrystalClear (Rigaku, 2011 ▶); cell refinement: CrystalClear; data reduction: CrystalClear; program(s) used to solve structure: SIR2004 (Burla et al., 2005 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: OLEX2 (Dolomanov et al., 2009 ▶); software used to prepare material for publication: CrystalStructure (Rigaku, 2010 ▶).

Supplementary Material

Crystal structure: contains datablock(s) General, I. DOI: 10.1107/S1600536814015438/pk2528sup1.cif

e-70-0o859-sup1.cif^{(28KB, cif)}

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536814015438/pk2528Isup2.hkl

e-70-0o859-Isup2.hkl^{(130KB, hkl)}

Click here for additional data file.^{(4.7KB, cml)}

Supporting information file. DOI: 10.1107/S1600536814015438/pk2528Isup3.cml

CCDC reference: 1011567

Additional supporting information: crystallographic information; 3D view; checkCIF report

Acknowledgments

The authors gratefully acknowledge the Endowed Chair in the Sciences, School of Humanitites, Arts, and Sciences, St Catherine University as well as the NSF–MRI award No. 1125975 "MRI Consortium: Acquisition of a Single Crystal X-ray Diffractometer for a Regional PUI Molecular Structure Facility".

supplementary crystallographic information

S1. Comment

4,4'-Methylene dianiline (4,4'-MDA) is principally used to produce 4,4'-methylene dianiline diisocyanate and other polymeric isocyanates, which are used to manufacture polyurethane foams. 4,4'-MDA is also used as a curing agent for epoxy resins and urethane elastomers, as a corrosion preventative for iron, as an antioxidant for lubricating oils, as a rubber processing chemical, and as an intermediate in the manufacture of elastomeric fibers. In the manufacturing process of 4,4'-MDA, by-products including 2,2'-methylene dianiline (2,2'-MDA) are produced. 2,2'-MDA can have hazardous health effects such as irritation to the skin and eyes, liver damage through acute oral or dermal exposure, and is a possible human carcinogen. In an effort to access 2,2'-MDA for use as a standard to measure the by-products created in the manufacturing process to synthesize 4,4'-MDA, we have developed a new synthesis of the intermediate 2,2'-dinitrodiphenylmethane and determined its crystal structure.

2,2'-MDA can be produced in a two-step synthesis from 2-nitrophenyl boronic acid and 2-nitrobenzyl bromide. First, 2-nitrophenyl boronic acid is reacted with 2-nitrobenzyl bromide using a Suzuki reaction to produce 2,2'-dinitrodiphenylmethane. Next, the nitro groups on the 2,2'-dinitrodiphenylmethane can be reduced using a catalytic hydrogenation reaction to produce the compound 2,2'-MDA.

The molecular structure of bis(2-nitrophenyl)methane (Fig. 1) is composed of an asymmetric unit containing one whole molecule. The N-O bond lengths (range 1.227 (2)-1.233 (2) Å) are consistent with a high degree of resonance in the nitro groups. Each nitro group is twisted from the bonded benzene moiety with angles between least-squares planes (N1, O1, O2 and C1-C6; N2, O3, O4 and C8-C13) of 16.64 (18)° and 28.02 (11)°, respectively. The benzene groups are nearly perpendicular with angles between least-squares planes of 87.72 (6)°. The orientation of the nitro groups allows for close intramolecular contacts between the oxygen atoms and methylene H atoms.

Close intermolecular contacts are also present in this structure. A short contact between N1 (x,y,z) and O2 (1 - x,2 - y, 1 - z) with a distance of 2.981 (2) Å (distance -van der Waals sum = -0.089 Å) is consistent with a weak nitro π - nitro π type interaction. These nitro groups, related by inversion, are parallel with an intermolecular distance between least-squares planes of 2.861 (3) Å. Likewise, C1 (x,y,z) and O2 (1-x, 2-y, 1-z) engage in a similar weak benzene π - nitro π type interaction at a distance of 3.060 (2) Å (distance -van der Waals sum = -0.161 Å). Short intermolecular contacts are also present between O4(x,y,z) ···H3(x,y + 1,z + 1) (2.53 Å) and O1(x, y,z)···H5 x - 1,y,z) (2.58 Å).

S2. Experimental

Compound (I) was prepared by a modification of the method used by Lu et al. (2006).

Under nitrogen, a mixture of THF (5.8 ml) and aqueous K₂CO₃ (2M, 2.3 ml, 9.3 mmol) were added to 2-nitrophenylboronic acid (0.257 g, 3.08 mmol), 2-nitrobenzylbromide (0.514 g, 2.8 mmol) and Pd(PPh₃)₄ (0.081 g, 0.07 mmol). The reaction mixture was heated under reflux and protected from light for 24h. Aqueous HCl (1M, 50 ml) was added, the reaction mixture was extracted with ethyl acetate (3 x 20 ml), dried using MgSO₄, and concentrated to yield a brown oil. The crude product was purified by flash chormatography (silica gel, hexanes/ethyl acetate (12:1)). Yellow X-ray quality crystals were obtained by evaporation of a hexanes/ethyl acetate (12:1) solution. Yield: 0.059 g, 16%. mp 84-85°C.