N-(4-Methyl­benz­yl)-3-nitro­aniline

In the title compound, C₁₄H₁₄N₂O₂, the angle between the mean plane of the N-methyl-3-nitro­aniline system (r.m.s. deviation = 0.0185 Å) and the p-tolyl unit is 89.79 (4)°. In the crystal, hydrogen-bonded chains running along [10-1] are generated by the linking of neighbouring mol­ecules via N—H...O and C—H...O hydrogen bonds involving the 3-nitro­aniline systems and forming R₂²(8) motifs.

Key indicators

• Single-crystal X-ray study
• T = 296 K
• Mean [sigma](C-C) = 0.004 Å
• R factor = 0.046
• wR factor = 0.117
• Data-to-parameter ratio = 11.1

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT480_ALERT_4_C Long H...A H-Bond Reported H7A    ..  O2      ..       2.64 Ang.
PLAT480_ALERT_4_C Long H...A H-Bond Reported H13    ..  O2      ..       2.69 Ang.
PLAT790_ALERT_4_C Centre of Gravity not Within Unit Cell: Resd.  #          1
              C14 H14 N2 O2
PLAT910_ALERT_3_C Missing # of FCF Reflections Below Th(Min) .....          7

Alert level G
REFLT03_ALERT_4_G Please check that the estimate of the number of Friedel pairs is
            correct. If it is not, please give the correct count in the
            _publ_section_exptl_refinement section of the submitted CIF.
           From the CIF: _diffrn_reflns_theta_max           30.00
           From the CIF: _reflns_number_total               1856
           Count of symmetry unique reflns         1863
           Completeness (_total/calc)             99.62%
           TEST3: Check Friedels for noncentro structure
           Estimate of Friedel pairs measured         0
           Fraction of Friedel pairs measured     0.000
           Are heavy atom types Z>Si present         no
PLAT005_ALERT_5_G No _iucr_refine_instructions_details in CIF ....          ?

   0 ALERT level A = Most likely a serious problem - resolve or explain
   0 ALERT level B = A potentially serious problem, consider carefully
   4 ALERT level C = Check. Ensure it is not caused by an omission or oversight
   2 ALERT level G = General information/check it is not something unexpected

   0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   0 ALERT type 2 Indicator that the structure model may be wrong or deficient
   1 ALERT type 3 Indicator that the structure quality may be low
   4 ALERT type 4 Improvement, methodology, query or suggestion
   1 ALERT type 5 Informative message, check

---

S1. Comment

The title compound, N-(4-methylbenzyl)-3-nitroaniline, is prepared as a part of the laboratory work with high school students, and the synthesis followed the Preparatory problems for the 40th International Chemistry Olympiad (Magyarfalvi, 2008) involving slight modifications.

Recently, N-benzyl-3-nitroaniline was reported (Stilinović & Portada, 2011). The difference between the title compound and the previously reported one is only in methyl substituent on the N-benzyl moiety, since it was of interest to study the influence of the benzyl moiety substituents on the molecular conformation, and consequently the hydrogen bonding formation.

The addition of methyl substituent on the benzyl moiety in the title compound did not cause any significant conformational difference. The molecule retained a bent conformation with the torsion angle about the central C—N bond of 73.9 (2)° being very similar to analogous one in the recently reported compound (Stilinović & Portada, 2011). Furthermore, the N-methyl-3-nitroaniline system in the title compound is nearly ideally planar (r.m.s. deviation of the atoms C1–C7/N1/N2/O1/O2 from their mean plane is 0.0185 Å, with oxygen atom O2 being the one that deviates most from that plane, 0.031 (2) Å). The p-tolyl substituent is tilted at an angle of 89.79 (4)° to the rest of the molecule.

Two neighbouring molecules are connected through the set of N—H···O and C—H···O hydrogen bonds in the head to tail manner forming R²₂(8) motifs (Etter, 1990; Bernstein et al., 1995) that generate one-dimensional chains running in the [101] direction. The same hydrogen bonding pattern is also found in N-benzyl-3-nitroaniline (Stilinović & Portada, 2011) what leads to the conclusion that the methyl substituent in p-position to the central C—N bond do not influence neither hydrogen bonding geometry nor general hydrogen bonding framework formation.

Related literature

For related structures, see: Betz et al. (2011); Stilinović & Portada (2011); Xing et al. (2006). For the synthesis, see: Magyarfalvi (2008). For graph-set theory, see: Etter (1990); Bernstein et al. (1995).

S2. Experimental

The title compound was prepared using a slightly modified procedure (Magyarfalvi, 2008) and isolated in a form of yellow crystalline product. Used: 3-nitroaniline (1.10 g; 7.96 mmol), p-tolualdehyde (1.74 ml; 1.77 g; 14.7 mmol), sodium tetrahydridoborate (0.50 g; 13.2 mmol). Yield: 1.12 g (58%). Upon re-crystallization in ethanol, yellow block-like crystalls suitable for the X-ray experiment were obtained in 3–4 days.

S3. Refinement

In the final cycles of refinement, in the absence of significant anomalous scattering effect, 1856 Friedel pairs were merged and Δf'' set to zero. The amine H atom was located in the difference Fourier map and freely refined, giving N—H distance of 0.78 (3) Å. All other H atoms were placed in geometrically idealized positions and constrained to ride on their parent C atom at distances of 0.93, 0.96 and 0.97 Å for aromatic, methyl and CH₂ H atoms, respectively, and with U_iso(H) = 1.2U_eq(C) (for aromatic and CH₂ H atoms), and U_iso(H) = 1.5U_eq(C) (for methyl group).

Computing details

Data collection: CrysAlis PRO (Oxford Diffraction, 2009); cell refinement: CrysAlis PRO (Oxford Diffraction, 2009); data reduction: CrysAlis PRO (Oxford Diffraction, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997) and Mercury (Macrae et al., 2006); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures

	Fig. 1. Molecular structure of the title compound with the atom labelling scheme. Displacement ellipsoids for non-H atoms are drawn at the 30% probability level. Hydrogen atoms are shown as a spheres of arbitrary radius.
	Fig. 2. Infinite one-dimensional chains running in the [101] direction constructed via N—H···O and C—H···O hydrogen bonds between neighbouring molecules forming R^22(8) motifs.

N-(4-Methylbenzyl)-3-nitroaniline

Crystal data

C14H14N2O2	F(000) = 256
Mr = 242.27	Dx = 1.288 Mg m^−3
Monoclinic, P21	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2 yb	Cell parameters from 4334 reflections
a = 5.1851 (4) Å	θ = 4.4–32.7°
b = 21.408 (2) Å	µ = 0.09 mm^−1
c = 5.6833 (4) Å	T = 296 K
β = 98.010 (7)°	Plate, yellow
V = 624.71 (8) Å^3	0.57 × 0.50 × 0.19 mm
Z = 2

Data collection

Oxford Diffraction Xcalibur diffractometer with a Sapphire-3 CCD area detector	1856 independent reflections
Radiation source: Enhance (Mo) X-ray Source	1373 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.042
Detector resolution: 16.3426 pixels mm^-1	θmax = 30.0°, θmin = 4.4°
CCD scans	h = −7→7
Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction, 2009)	k = −30→30
Tmin = 0.953, Tmax = 0.958	l = −7→7
11868 measured reflections

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.046	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.117	H atoms treated by a mixture of independent and constrained refinement
S = 1.03	w = 1/[σ^2(Fo^2) + (0.0688P)^2] where P = (Fo^2 + 2Fc^2)/3
1856 reflections	(Δ/σ)max < 0.001
167 parameters	Δρmax = 0.16 e Å^−3
1 restraint	Δρmin = −0.11 e Å^−3

Special details

Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell e.s.d.'s are taken into account in the estimation of distances, angles and torsion angles

Refinement. Refinement on F² for ALL reflections except those flagged by the user for potential systematic errors. Weighted R-factors wR and all goodnesses of fit S are based on F², conventional R-factors R are based on F, with F set to zero for negative F². The observed criterion of F² > σ(F²) is used only for calculating -R-factor-obs 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 (Ų)

	x	y	z	Uiso*/Ueq
O1	0.0400 (4)	0.59135 (11)	0.2460 (4)	0.0814 (8)
O2	0.1836 (4)	0.49767 (11)	0.2911 (3)	0.0688 (7)
N1	0.8389 (4)	0.47827 (11)	−0.2730 (5)	0.0645 (8)
N2	0.1802 (4)	0.54885 (10)	0.1976 (3)	0.0525 (7)
C1	0.6686 (4)	0.52300 (11)	−0.2149 (4)	0.0455 (6)
C2	0.5065 (4)	0.51224 (10)	−0.0402 (4)	0.0417 (6)
C3	0.3489 (4)	0.56021 (10)	0.0150 (4)	0.0434 (6)
C4	0.3374 (5)	0.61797 (11)	−0.0925 (5)	0.0564 (8)
C5	0.4936 (5)	0.62762 (13)	−0.2656 (5)	0.0627 (9)
C6	0.6563 (5)	0.58119 (12)	−0.3245 (4)	0.0558 (8)
C7	0.8676 (5)	0.41780 (13)	−0.1683 (5)	0.0619 (8)
C8	0.6482 (4)	0.37253 (11)	−0.2473 (4)	0.0511 (7)
C9	0.5891 (6)	0.32463 (15)	−0.1024 (5)	0.0703 (10)
C10	0.3929 (7)	0.28214 (14)	−0.1763 (6)	0.0747 (11)
C11	0.2506 (6)	0.28531 (12)	−0.3980 (5)	0.0628 (9)
C12	0.3078 (6)	0.33344 (14)	−0.5412 (5)	0.0669 (9)
C13	0.5021 (6)	0.37587 (13)	−0.4681 (5)	0.0608 (8)
C14	0.0335 (7)	0.23991 (16)	−0.4795 (9)	0.0912 (13)
H1N	0.913 (6)	0.4885 (14)	−0.376 (5)	0.061 (8)*
H2	0.50580	0.47380	0.03580	0.0500*
H4	0.22830	0.64920	−0.04980	0.0680*
H5	0.48930	0.66590	−0.34350	0.0750*
H6	0.76130	0.58890	−0.44120	0.0670*
H7A	0.88320	0.42240	0.00290	0.0740*
H7B	1.02900	0.39970	−0.20470	0.0740*
H9	0.68320	0.32070	0.04860	0.0840*
H10	0.35690	0.25070	−0.07280	0.0890*
H12	0.21290	0.33750	−0.69180	0.0800*
H13	0.53540	0.40770	−0.57100	0.0730*
H14A	−0.04300	0.25020	−0.63840	0.1370*
H14B	−0.09690	0.24240	−0.37530	0.1370*
H14C	0.10230	0.19820	−0.47650	0.1370*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0779 (13)	0.0904 (15)	0.0858 (13)	0.0136 (12)	0.0468 (11)	−0.0109 (11)
O2	0.0736 (12)	0.0795 (13)	0.0590 (10)	−0.0050 (10)	0.0297 (9)	0.0073 (10)
N1	0.0566 (13)	0.0626 (13)	0.0834 (15)	−0.0065 (10)	0.0420 (12)	−0.0110 (11)
N2	0.0432 (10)	0.0693 (14)	0.0474 (10)	−0.0029 (9)	0.0144 (8)	−0.0086 (10)
C1	0.0394 (10)	0.0524 (12)	0.0462 (11)	−0.0081 (9)	0.0108 (8)	−0.0108 (9)
C2	0.0376 (9)	0.0446 (11)	0.0443 (10)	−0.0026 (8)	0.0111 (8)	−0.0001 (8)
C3	0.0394 (10)	0.0537 (12)	0.0387 (9)	−0.0031 (9)	0.0116 (8)	−0.0042 (8)
C4	0.0525 (13)	0.0498 (13)	0.0695 (14)	0.0056 (11)	0.0173 (11)	−0.0005 (12)
C5	0.0689 (16)	0.0546 (14)	0.0668 (15)	0.0009 (12)	0.0177 (13)	0.0136 (12)
C6	0.0534 (13)	0.0654 (15)	0.0530 (13)	−0.0136 (11)	0.0226 (10)	0.0013 (11)
C7	0.0446 (12)	0.0669 (15)	0.0753 (16)	0.0093 (12)	0.0120 (11)	−0.0171 (13)
C8	0.0521 (12)	0.0502 (12)	0.0528 (12)	0.0131 (10)	0.0142 (10)	−0.0040 (10)
C9	0.0801 (19)	0.0749 (17)	0.0551 (14)	0.0082 (16)	0.0069 (13)	0.0144 (14)
C10	0.085 (2)	0.0564 (15)	0.088 (2)	0.0077 (14)	0.0303 (17)	0.0262 (15)
C11	0.0629 (16)	0.0478 (13)	0.0820 (19)	0.0067 (11)	0.0252 (15)	−0.0065 (13)
C12	0.0719 (17)	0.0706 (17)	0.0572 (14)	−0.0026 (14)	0.0057 (12)	−0.0049 (13)
C13	0.0720 (15)	0.0569 (13)	0.0547 (13)	−0.0022 (13)	0.0135 (11)	0.0080 (12)
C14	0.078 (2)	0.0619 (18)	0.137 (3)	−0.0059 (15)	0.027 (2)	−0.021 (2)

Geometric parameters (Å, º)

O1—N2	1.220 (3)	C11—C14	1.510 (5)
O2—N2	1.217 (3)	C11—C12	1.371 (4)
N1—C1	1.374 (3)	C12—C13	1.377 (4)
N1—C7	1.424 (4)	C2—H2	0.9300
N2—C3	1.468 (3)	C4—H4	0.9300
N1—H1N	0.78 (3)	C5—H5	0.9300
C1—C6	1.390 (3)	C6—H6	0.9300
C1—C2	1.406 (3)	C7—H7A	0.9700
C2—C3	1.376 (3)	C7—H7B	0.9700
C3—C4	1.377 (3)	C9—H9	0.9300
C4—C5	1.374 (4)	C10—H10	0.9300
C5—C6	1.375 (4)	C12—H12	0.9300
C7—C8	1.514 (4)	C13—H13	0.9300
C8—C13	1.374 (4)	C14—H14A	0.9600
C8—C9	1.376 (4)	C14—H14B	0.9600
C9—C10	1.386 (5)	C14—H14C	0.9600
C10—C11	1.370 (4)
O1···C1^i	3.362 (3)	C13···H7B^i	3.0900
O1···C6^ii	3.364 (3)	H1N···O2^vi	2.52 (3)
O2···C7^i	3.352 (3)	H1N···H6	2.3000
O2···C13^iii	3.282 (4)	H2···O2	2.4200
O1···H14C^iv	2.7900	H2···C7	2.6300
O1···H4	2.4000	H2···C8	2.8600
O1···H6^ii	2.4400	H2···H7A	2.2800
O2···H1N^ii	2.52 (3)	H4···O1	2.4000
O2···H2	2.4200	H5···H14C^viii	2.5700
O2···H7A^i	2.6400	H6···O1^vi	2.4400
O2···H13^iii	2.6900	H6···H1N	2.3000
N1···C3^v	3.398 (3)	H6···H14C^viii	2.5100
N2···C1^i	3.333 (3)	H7A···O2^v	2.6400
N1···H13	2.6200	H7A···C2	2.7300
C1···O1^v	3.362 (3)	H7A···H2	2.2800
C1···N2^v	3.333 (3)	H7A···H9	2.4400
C1···C13	3.520 (4)	H7B···C11^v	2.9800
C2···C8	3.333 (3)	H7B···C12^v	2.9200
C3···N1^i	3.398 (3)	H7B···C13^v	3.0900
C6···O1^vi	3.364 (3)	H9···H7A	2.4400
C7···O2^v	3.352 (3)	H9···H14A^ix	2.6000
C8···C2	3.333 (3)	H12···H14A	2.3400
C13···C1	3.520 (4)	H13···O2^vii	2.6900
C13···O2^vii	3.282 (4)	H13···N1	2.6200
C2···H7A	2.7300	H14A···H9^x	2.6000
C6···H14C^viii	3.0800	H14A···H12	2.3400
C7···H2	2.6300	H14B···C9^i	2.9800
C8···H2	2.8600	H14C···O1^xi	2.7900
C9···H14B^v	2.9800	H14C···C6^xii	3.0800
C11···H7B^i	2.9800	H14C···H5^xii	2.5700
C12···H7B^i	2.9200	H14C···H6^xii	2.5100
C1—N1—C7	124.5 (2)	C1—C2—H2	121.00
O1—N2—O2	123.1 (2)	C3—C2—H2	121.00
O1—N2—C3	117.9 (2)	C3—C4—H4	121.00
O2—N2—C3	119.0 (2)	C5—C4—H4	121.00
C7—N1—H1N	123 (2)	C4—C5—H5	120.00
C1—N1—H1N	113 (2)	C6—C5—H5	120.00
N1—C1—C6	120.5 (2)	C1—C6—H6	119.00
C2—C1—C6	117.9 (2)	C5—C6—H6	119.00
N1—C1—C2	121.5 (2)	N1—C7—H7A	108.00
C1—C2—C3	118.1 (2)	N1—C7—H7B	108.00
N2—C3—C4	118.0 (2)	C8—C7—H7A	108.00
N2—C3—C2	117.97 (19)	C8—C7—H7B	108.00
C2—C3—C4	124.0 (2)	H7A—C7—H7B	107.00
C3—C4—C5	117.3 (2)	C8—C9—H9	119.00
C4—C5—C6	120.6 (2)	C10—C9—H9	119.00
C1—C6—C5	122.0 (2)	C9—C10—H10	119.00
N1—C7—C8	115.3 (2)	C11—C10—H10	119.00
C9—C8—C13	116.4 (2)	C11—C12—H12	119.00
C7—C8—C9	121.4 (2)	C13—C12—H12	119.00
C7—C8—C13	122.2 (2)	C8—C13—H13	119.00
C8—C9—C10	121.5 (3)	C12—C13—H13	119.00
C9—C10—C11	121.7 (3)	C11—C14—H14A	109.00
C10—C11—C14	122.2 (3)	C11—C14—H14B	110.00
C10—C11—C12	116.7 (3)	C11—C14—H14C	109.00
C12—C11—C14	121.0 (3)	H14A—C14—H14B	109.00
C11—C12—C13	121.8 (3)	H14A—C14—H14C	109.00
C8—C13—C12	121.9 (3)	H14B—C14—H14C	109.00
C7—N1—C1—C2	0.7 (4)	C3—C4—C5—C6	−0.9 (4)
C7—N1—C1—C6	179.2 (2)	C4—C5—C6—C1	0.6 (4)
C1—N1—C7—C8	73.9 (3)	N1—C7—C8—C9	−152.7 (3)
O1—N2—C3—C2	−179.8 (2)	N1—C7—C8—C13	29.0 (4)
O1—N2—C3—C4	−0.6 (3)	C7—C8—C13—C12	178.1 (3)
O2—N2—C3—C2	−0.8 (3)	C7—C8—C9—C10	−178.3 (3)
O2—N2—C3—C4	178.5 (2)	C13—C8—C9—C10	0.1 (4)
N1—C1—C2—C3	177.4 (2)	C9—C8—C13—C12	−0.3 (4)
C6—C1—C2—C3	−1.1 (3)	C8—C9—C10—C11	0.8 (5)
N1—C1—C6—C5	−178.1 (2)	C9—C10—C11—C12	−1.5 (5)
C2—C1—C6—C5	0.5 (4)	C9—C10—C11—C14	−179.0 (3)
C1—C2—C3—N2	−179.93 (19)	C10—C11—C12—C13	1.3 (5)
C1—C2—C3—C4	0.9 (3)	C14—C11—C12—C13	178.9 (3)
N2—C3—C4—C5	−179.1 (2)	C11—C12—C13—C8	−0.4 (5)
C2—C3—C4—C5	0.1 (4)

Symmetry codes: (i) x−1, y, z; (ii) x−1, y, z+1; (iii) x, y, z+1; (iv) −x, y+1/2, −z; (v) x+1, y, z; (vi) x+1, y, z−1; (vii) x, y, z−1; (viii) −x+1, y+1/2, −z−1; (ix) x+1, y, z+1; (x) x−1, y, z−1; (xi) −x, y−1/2, −z; (xii) −x+1, y−1/2, −z−1.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1N···O2^vi	0.78 (3)	2.52 (3)	3.277 (3)	168 (3)
C6—H6···O1^vi	0.93	2.44	3.364 (3)	171
C7—H7A···O2^v	0.97	2.64	3.352 (3)	130
C13—H13···O2^vii	0.93	2.69	3.282 (4)	122

Symmetry codes: (v) x+1, y, z; (vi) x+1, y, z−1; (vii) x, y, z−1.