4-Nitroaniline–2,4,6-trimethoxybenz­aldehyde (1/1)

Asiri, A.M.; Khan, S.A.; Tan, K.W.; Ng, S.W.

doi:10.1107/S1600536810023664

organic compounds

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ISSN: 2056-9890

Volume 66| Part 7| July 2010| Page o1765

doi:10.1107/S1600536810023664

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4-Nitroaniline–2,4,6-trimethoxybenzaldehyde (1/1)

Abdullah M. Asiri,^a Salman A. Khan,^a Kong Wai Tan ^b and Seik Weng Ng ^b ^*

^aChemistry Department, Faculty of Science, King Abdul Aziz University, PO Box 80203, Jeddah 21589, Saudi Arabia, and ^bDepartment of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia
^*Correspondence e-mail: seikweng@um.edu.my

(Received 15 June 2010; accepted 18 June 2010; online 23 June 2010)

In the title co-crystal, C₆H₆N₂O_2.C₁₀H₁₂O₄, the two components are held together by an N—H⋯O_aldehyde hydrogen bond. Adjacent co-crystals are linked by weaker N—H⋯O_nitro hydrogen bonds, forming a linear chain. The two aromatic rings of the components are aligned at 75.2 (1)°. The crystal studied was a non-merohedral twin with a 24% minor component.

Related literature

For some examples of co-crystals of 4-nitroaniline, see: Bertolasi et al. (2001 ); Dederer & Gieren (1979 ); Huang et al. (1996 ); Koshima et al. (1996 ); Rashid & Deschamps (2006 ); Singh et al. (2003 ); Smith et al. (1997 ); Weber (1981 ); Zaitu et al. (1995 ). For the treatment of non-merohedral twins, see: Spek (2009 ).

Experimental

Crystal data

C₆H₆N₂O₂·C₁₀H₁₂O₄
M_r = 334.32
Monoclinic, P 2₁ /c
a = 7.4409 (11) Å
b = 30.022 (5) Å
c = 6.9400 (11) Å
β = 93.237 (3)°
V = 1547.9 (4) Å³
Z = 4
Mo Kα radiation
μ = 0.11 mm⁻¹
T = 100 K
0.15 × 0.10 × 0.05 mm

Data collection

Bruker SMART APEX diffractometer
8127 measured reflections
2722 independent reflections
1834 reflections with I > 2σ(I)
R_int = 0.059

Refinement

R[F² > 2σ(F²)] = 0.049
wR(F²) = 0.124
S = 1.01
2722 reflections
221 parameters
H-atom parameters constrained
Δρ_max = 0.22 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
N1—H12⋯O1	0.86	2.16	3.016 (3)	172
N1—H11⋯O5ⁱ	0.86	2.50	3.288 (3)	152
N1—H11⋯O6ⁱ	0.86	2.50	3.293 (3)	154
Symmetry code: (i) $[x+1, -y+{\script{3\over 2}}, z+{\script{1\over 2}}]$ .

Data collection: APEX2 (Bruker, 2009 ); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: X-SEED (Barbour, 2001 ); software used to prepare material for publication: publCIF (Westrip, 2010 ).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536810023664/si2271sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536810023664/si2271Isup2.hkl

checkCIF report

Comment top

Aromatic aldehydes readily condense with aromatic amines to yield Schiff bases. However, 2,4,6-trimethoxylbenzaldehyde and 4-nitroaniline reactants did not condense but instead co-crystallized in the attempted synthesis. The condensation probably did not proceed owing to the decreased basicity of the amino group, which is situated opposite the electron-withdrawing nitro group in the aromatic ring. The co-crystal (Scheme I, Fig. 1) has the components linked by an H–N···O hydrogen bond; the two aromatic rings aligned at 75.2 (1) °. Adjacent co-crystals are linked by weaker N–H···O_nitro hydrogen bonds to form a linear chain.

4-Nitroaniline forms a number of co-crystals with other neutral compounds; for their description, see: Bertolasi et al. (2001); Dederer & Gieren (1979); Huang et al. (1996); Koshima et al. (1996); Rashid & Deschamps (2006); Singh et al. (2003); Smith et al. (1997); Weber (1981); Zaitu et al. (1995).

Related literature top

For some examples of co-crystals of 4-nitroaniline, see: Bertolasi et al. (2001); Dederer & Gieren (1979); Huang et al. (1996); Koshima et al. (1996); Rashid & Deschamps (2006); Singh et al. (2003); Smith et al. (1997); Weber (1981); Zaitu et al. (1995). For the treatment of non-merohedral twins, see: Spek (2009).

Experimental top

2,4, 6-Trimethoxybenzaldehyde (0.50 g, 3.3 mmol) and 4-nitroaniline (0.57 g, 3.3 mmol) were heated in methanol (15 ml) for 5 h. Yellow crystals separated from the cool solution after a day.

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: X-SEED (Barbour, 2001); software used to prepare material for publication: publCIF (Westrip, 2010).

Figures top

Fig. 1. Thermal ellipsoid plot (Barbour, 2001) of the C₆H₆N₂O₂–C₁₀H₁₂O₄ co-crystal at the 70% probability level; hydrogen atoms are drawn as spheres of arbitrary radius.

4-Nitroaniline–2,4,6-trimethoxybenzaldehyde (1/1) top

Crystal data top

C₆H₆N₂O₂·C₁₀H₁₂O₄	F(000) = 704
M_r = 334.32	D_x = 1.435 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 1019 reflections
a = 7.4409 (11) Å	θ = 2.7–24.4°
b = 30.022 (5) Å	µ = 0.11 mm⁻¹
c = 6.9400 (11) Å	T = 100 K
β = 93.237 (3)°	Prism, yellow
V = 1547.9 (4) Å³	0.15 × 0.10 × 0.05 mm
Z = 4

Data collection top

Bruker SMART APEX diffractometer	1834 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	R_int = 0.059
Graphite monochromator	θ_max = 25.0°, θ_min = 1.4°
ω scans	h = −8→8
8127 measured reflections	k = −32→35
2722 independent reflections	l = −8→8

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)] = 0.049	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.124	H-atom parameters constrained
S = 1.01	w = 1/[σ²(F_o²) + (0.0537P)² + 0.141P] where P = (F_o² + 2F_c²)/3
2722 reflections	(Δ/σ)_max = 0.001
221 parameters	Δρ_max = 0.22 e Å⁻³
0 restraints	Δρ_min = −0.41 e Å⁻³

Crystal data top

C₆H₆N₂O₂·C₁₀H₁₂O₄	V = 1547.9 (4) Å³
M_r = 334.32	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 7.4409 (11) Å	µ = 0.11 mm⁻¹
b = 30.022 (5) Å	T = 100 K
c = 6.9400 (11) Å	0.15 × 0.10 × 0.05 mm
β = 93.237 (3)°

Data collection top

Bruker SMART APEX diffractometer	1834 reflections with I > 2σ(I)
8127 measured reflections	R_int = 0.059
2722 independent reflections

Refinement top

R[F² > 2σ(F²)] = 0.049	0 restraints
wR(F²) = 0.124	H-atom parameters constrained
S = 1.01	Δρ_max = 0.22 e Å⁻³
2722 reflections	Δρ_min = −0.41 e Å⁻³
221 parameters

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

	x	y	z	U_iso*/U_eq
O1	0.7019 (2)	0.57392 (6)	0.7861 (3)	0.0238 (5)
O2	0.7670 (2)	0.61120 (6)	0.4418 (2)	0.0182 (4)
O3	1.3371 (2)	0.57367 (6)	0.1850 (2)	0.0203 (4)
O4	1.1646 (2)	0.51253 (6)	0.7725 (2)	0.0176 (4)
O5	0.0363 (2)	0.80574 (6)	0.5273 (3)	0.0266 (5)
O6	−0.0908 (2)	0.74324 (7)	0.4450 (3)	0.0291 (5)
N1	0.6593 (3)	0.67379 (7)	0.7727 (3)	0.0233 (5)
H11	0.7505	0.6884	0.8209	0.028*
H12	0.6631	0.6452	0.7670	0.028*
N2	0.0398 (3)	0.76456 (7)	0.5159 (3)	0.0193 (5)
C1	0.8433 (3)	0.55435 (8)	0.7589 (4)	0.0177 (6)
H1	0.8764	0.5314	0.8482	0.021*
C2	0.9658 (3)	0.56212 (8)	0.6066 (3)	0.0152 (6)
C3	0.9285 (3)	0.59010 (8)	0.4462 (4)	0.0154 (6)
C4	1.0482 (3)	0.59515 (8)	0.3011 (4)	0.0155 (6)
H4	1.0203	0.6140	0.1936	0.019*
C5	1.2098 (3)	0.57189 (8)	0.3175 (4)	0.0157 (6)
C6	1.2542 (3)	0.54410 (8)	0.4744 (4)	0.0170 (6)
H6	1.3662	0.5289	0.4834	0.020*
C7	1.1335 (3)	0.53914 (8)	0.6155 (3)	0.0144 (6)
C8	0.7184 (3)	0.63908 (9)	0.2781 (4)	0.0216 (6)
H8A	0.5983	0.6516	0.2923	0.032*
H8B	0.7179	0.6213	0.1597	0.032*
H8C	0.8061	0.6633	0.2709	0.032*
C9	1.3034 (3)	0.60080 (8)	0.0177 (4)	0.0198 (6)
H9A	1.4039	0.5980	−0.0669	0.030*
H9B	1.2913	0.6320	0.0570	0.030*
H9C	1.1920	0.5910	−0.0516	0.030*
C10	1.3340 (3)	0.48903 (9)	0.7879 (4)	0.0193 (6)
H10A	1.3403	0.4709	0.9054	0.029*
H10B	1.4332	0.5106	0.7934	0.029*
H10C	1.3436	0.4697	0.6751	0.029*
C11	0.5099 (3)	0.69579 (9)	0.7057 (3)	0.0168 (6)
C12	0.3577 (3)	0.67245 (9)	0.6292 (4)	0.0189 (6)
H12A	0.3622	0.6409	0.6183	0.023*
C13	0.2034 (3)	0.69466 (9)	0.5705 (4)	0.0186 (6)
H13	0.1006	0.6786	0.5216	0.022*
C14	0.1986 (3)	0.74094 (8)	0.5832 (4)	0.0165 (6)
C15	0.3483 (3)	0.76498 (8)	0.6542 (3)	0.0162 (6)
H15	0.3440	0.7966	0.6610	0.019*
C16	0.5015 (3)	0.74254 (9)	0.7139 (4)	0.0176 (6)
H16	0.6040	0.7588	0.7617	0.021*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.0193 (10)	0.0228 (11)	0.0302 (11)	0.0076 (8)	0.0082 (8)	0.0052 (9)
O2	0.0152 (9)	0.0201 (10)	0.0195 (10)	0.0065 (8)	0.0028 (7)	0.0045 (8)
O3	0.0188 (10)	0.0228 (11)	0.0200 (10)	0.0060 (8)	0.0070 (8)	0.0085 (8)
O4	0.0163 (9)	0.0172 (10)	0.0195 (10)	0.0054 (7)	0.0023 (7)	0.0049 (8)
O5	0.0257 (11)	0.0204 (12)	0.0337 (12)	0.0076 (9)	0.0015 (8)	0.0010 (9)
O6	0.0173 (10)	0.0360 (13)	0.0332 (12)	−0.0005 (9)	−0.0068 (9)	−0.0050 (10)
N1	0.0213 (12)	0.0170 (13)	0.0311 (13)	0.0035 (10)	−0.0030 (10)	−0.0009 (11)
N2	0.0183 (12)	0.0219 (14)	0.0178 (12)	0.0011 (10)	0.0028 (9)	−0.0001 (10)
C1	0.0207 (14)	0.0123 (14)	0.0201 (14)	0.0010 (12)	0.0005 (11)	0.0014 (11)
C2	0.0160 (13)	0.0131 (14)	0.0165 (13)	−0.0013 (10)	0.0012 (10)	−0.0016 (11)
C3	0.0133 (13)	0.0136 (14)	0.0189 (13)	0.0016 (11)	−0.0017 (10)	−0.0027 (11)
C4	0.0157 (13)	0.0139 (14)	0.0171 (13)	−0.0008 (10)	0.0015 (10)	−0.0010 (11)
C5	0.0154 (13)	0.0147 (14)	0.0174 (13)	−0.0017 (11)	0.0039 (10)	−0.0015 (11)
C6	0.0136 (13)	0.0142 (14)	0.0230 (14)	0.0022 (11)	−0.0003 (11)	0.0002 (11)
C7	0.0190 (14)	0.0098 (14)	0.0141 (13)	−0.0002 (10)	−0.0012 (10)	−0.0018 (11)
C8	0.0207 (14)	0.0211 (16)	0.0227 (14)	0.0046 (12)	−0.0017 (11)	0.0062 (12)
C9	0.0239 (15)	0.0173 (15)	0.0185 (14)	0.0015 (11)	0.0035 (11)	0.0044 (12)
C10	0.0148 (13)	0.0199 (15)	0.0230 (14)	0.0057 (11)	0.0004 (11)	0.0045 (12)
C11	0.0205 (14)	0.0186 (15)	0.0118 (13)	0.0037 (11)	0.0052 (11)	−0.0005 (11)
C12	0.0246 (14)	0.0121 (14)	0.0200 (14)	−0.0020 (12)	0.0025 (11)	0.0003 (11)
C13	0.0175 (14)	0.0218 (16)	0.0166 (14)	−0.0044 (12)	0.0029 (11)	−0.0013 (12)
C14	0.0154 (13)	0.0175 (15)	0.0168 (13)	0.0009 (11)	0.0011 (10)	0.0009 (11)
C15	0.0212 (14)	0.0122 (14)	0.0158 (13)	−0.0003 (11)	0.0056 (11)	−0.0014 (11)
C16	0.0165 (13)	0.0210 (16)	0.0152 (13)	0.0000 (11)	0.0011 (11)	−0.0023 (11)

Geometric parameters (Å, º) top

O1—C1	1.229 (3)	C6—C7	1.374 (3)
O2—C3	1.357 (3)	C6—H6	0.9500
O2—C8	1.441 (3)	C8—H8A	0.9800
O3—C5	1.358 (3)	C8—H8B	0.9800
O3—C9	1.428 (3)	C8—H8C	0.9800
O4—C7	1.360 (3)	C9—H9A	0.9800
O4—C10	1.444 (3)	C9—H9B	0.9800
O5—N2	1.239 (3)	C9—H9C	0.9800
O6—N2	1.242 (3)	C10—H10A	0.9800
N1—C11	1.352 (3)	C10—H10B	0.9800
N1—H11	0.8600	C10—H10C	0.9800
N1—H12	0.8600	C11—C16	1.406 (4)
N2—C14	1.434 (3)	C11—C12	1.410 (3)
C1—C2	1.454 (3)	C12—C13	1.370 (3)
C1—H1	0.9500	C12—H12A	0.9500
C2—C3	1.409 (3)	C13—C14	1.393 (3)
C2—C7	1.424 (3)	C13—H13	0.9500
C3—C4	1.390 (3)	C14—C15	1.394 (3)
C4—C5	1.389 (3)	C15—C16	1.368 (3)
C4—H4	0.9500	C15—H15	0.9500
C5—C6	1.397 (3)	C16—H16	0.9500

C3—O2—C8	118.10 (19)	O2—C8—H8C	109.5
C5—O3—C9	118.39 (19)	H8A—C8—H8C	109.5
C7—O4—C10	117.03 (19)	H8B—C8—H8C	109.5
C11—N1—H11	120.0	O3—C9—H9A	109.5
C11—N1—H12	120.0	O3—C9—H9B	109.5
H11—N1—H12	120.0	H9A—C9—H9B	109.5
O5—N2—O6	121.4 (2)	O3—C9—H9C	109.5
O5—N2—C14	119.5 (2)	H9A—C9—H9C	109.5
O6—N2—C14	119.1 (2)	H9B—C9—H9C	109.5
O1—C1—C2	127.8 (2)	O4—C10—H10A	109.5
O1—C1—H1	116.1	O4—C10—H10B	109.5
C2—C1—H1	116.1	H10A—C10—H10B	109.5
C3—C2—C7	117.2 (2)	O4—C10—H10C	109.5
C3—C2—C1	124.5 (2)	H10A—C10—H10C	109.5
C7—C2—C1	118.3 (2)	H10B—C10—H10C	109.5
O2—C3—C4	122.4 (2)	N1—C11—C16	120.7 (2)
O2—C3—C2	115.5 (2)	N1—C11—C12	120.9 (2)
C4—C3—C2	122.1 (2)	C16—C11—C12	118.3 (2)
C3—C4—C5	118.2 (2)	C13—C12—C11	120.8 (2)
C3—C4—H4	120.9	C13—C12—H12A	119.6
C5—C4—H4	120.9	C11—C12—H12A	119.6
O3—C5—C4	123.9 (2)	C12—C13—C14	119.4 (2)
O3—C5—C6	114.1 (2)	C12—C13—H13	120.3
C4—C5—C6	122.0 (2)	C14—C13—H13	120.3
C7—C6—C5	119.0 (2)	C15—C14—C13	121.1 (2)
C7—C6—H6	120.5	C15—C14—N2	119.1 (2)
C5—C6—H6	120.5	C13—C14—N2	119.7 (2)
O4—C7—C6	123.1 (2)	C16—C15—C14	119.2 (2)
O4—C7—C2	115.4 (2)	C16—C15—H15	120.4
C6—C7—C2	121.5 (2)	C14—C15—H15	120.4
O2—C8—H8A	109.5	C15—C16—C11	121.2 (2)
O2—C8—H8B	109.5	C15—C16—H16	119.4
H8A—C8—H8B	109.5	C11—C16—H16	119.4

O1—C1—C2—C3	−9.3 (4)	C5—C6—C7—C2	−0.9 (4)
O1—C1—C2—C7	172.5 (2)	C3—C2—C7—O4	179.9 (2)
C8—O2—C3—C4	1.2 (3)	C1—C2—C7—O4	−1.8 (3)
C8—O2—C3—C2	−177.9 (2)	C3—C2—C7—C6	0.2 (3)
C7—C2—C3—O2	179.5 (2)	C1—C2—C7—C6	178.6 (2)
C1—C2—C3—O2	1.3 (4)	N1—C11—C12—C13	176.7 (2)
C7—C2—C3—C4	0.5 (3)	C16—C11—C12—C13	−2.2 (4)
C1—C2—C3—C4	−177.7 (2)	C11—C12—C13—C14	1.3 (4)
O2—C3—C4—C5	−179.5 (2)	C12—C13—C14—C15	0.2 (4)
C2—C3—C4—C5	−0.5 (4)	C12—C13—C14—N2	177.8 (2)
C9—O3—C5—C4	−0.4 (3)	O5—N2—C14—C15	−2.2 (3)
C9—O3—C5—C6	179.3 (2)	O6—N2—C14—C15	176.9 (2)
C3—C4—C5—O3	179.4 (2)	O5—N2—C14—C13	−179.9 (2)
C3—C4—C5—C6	−0.2 (4)	O6—N2—C14—C13	−0.8 (3)
O3—C5—C6—C7	−178.8 (2)	C13—C14—C15—C16	−0.6 (4)
C4—C5—C6—C7	0.9 (4)	N2—C14—C15—C16	−178.3 (2)
C10—O4—C7—C6	0.3 (3)	C14—C15—C16—C11	−0.3 (4)
C10—O4—C7—C2	−179.4 (2)	N1—C11—C16—C15	−177.2 (2)
C5—C6—C7—O4	179.5 (2)	C12—C11—C16—C15	1.7 (4)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H12···O1	0.86	2.16	3.016 (3)	172
N1—H11···O5ⁱ	0.86	2.50	3.288 (3)	152
N1—H11···O6ⁱ	0.86	2.50	3.293 (3)	154

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

Experimental details

Crystal data
Chemical formula	C₆H₆N₂O₂·C₁₀H₁₂O₄
M_r	334.32
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	100
a, b, c (Å)	7.4409 (11), 30.022 (5), 6.9400 (11)
β (°)	93.237 (3)
V (Å³)	1547.9 (4)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.11
Crystal size (mm)	0.15 × 0.10 × 0.05

Data collection
Diffractometer	Bruker SMART APEX diffractometer
Absorption correction	–
No. of measured, independent and observed [I > 2σ(I)] reflections	8127, 2722, 1834
R_int	0.059
(sin θ/λ)_max (Å⁻¹)	0.594

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.049, 0.124, 1.01
No. of reflections	2722
No. of parameters	221
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.22, −0.41

Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), X-SEED (Barbour, 2001), publCIF (Westrip, 2010).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H12···O1	0.86	2.16	3.016 (3)	172
N1—H11···O5ⁱ	0.86	2.50	3.288 (3)	152
N1—H11···O6ⁱ	0.86	2.50	3.293 (3)	154

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

Acknowledgements

We thank King Abdul Aziz University and the University of Malaya for supporting this study.

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