2-{(E)-[(4-Methyl-phen-yl)imino]-meth-yl}-4-nitro-phenol-2-{(E)-[(4-methyl-phen-yl)iminio]meth-yl}-4-nitro-phenolate (0.60/0.40).

The crystal of the title compound, 0.6C(14)H(12)N(2)O(3)·0.4C(14)H(12)N(2)O(3), contains a mixture of its neutral (OH containing) and zwitterionic (NH containing) forms, in a 0.60 (4):0.40 (4) ratio. The former generates an S(6) loop via an intra-molecular O-H⋯N hydrogen bond and the latter generates an S(6) loop via an N-H⋯O hydro-gren bond. The aromatic rings are oriented at a dihedral angle of 42.52 (10)°. In the crystal, C-H⋯π inter-actions occur and aromatic π-π stacking inter-actions [centroid-centroid separations = 3.7106 (12) and 3.9177 (13) Å] consolidate the packing.

Related literature

For related structures, see: Hijji et al. (2009 ▶); Kılıç et al. (2009 ▶). For graph-set notation, see: Bernstein et al. (1995 ▶).

Experimental

Crystal data

0.6C14H12N2O3·0.4C14H12N2O3

M = 256.26

Monoclinic,

a = 14.0623 (6) Å

b = 14.1723 (8) Å

c = 6.2357 (3) Å

β = 95.400 (2)°

V = 1237.23 (11) Å3

Z = 4

Mo Kα radiation

μ = 0.10 mm−1

T = 296 K

0.25 × 0.22 × 0.20 mm

Data collection

Bruker Kappa APEXII CCD diffractometer

Absorption correction: multi-scan (SADABS; Bruker, 2005 ▶) T min = 0.976, T max = 0.985

9733 measured reflections

2238 independent reflections

1395 reflections with I > 2σ(I)

R int = 0.041

Refinement

R[F 2 > 2σ(F 2)] = 0.049

wR(F 2) = 0.133

S = 1.03

2238 reflections

181 parameters

H atoms treated by a mixture of independent and constrained refinement

Δρmax = 0.20 e Å−3

Δρmin = −0.18 e Å−3

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: ORTEP-3 for Windows (Farrugia, 1997 ▶) and PLATON (Spek, 2009 ▶); software used to prepare material for publication: WinGX (Farrugia, 1999 ▶) and PLATON (Spek, 2009 ▶).

Crystal structure: contains datablock(s) global, I. DOI: 10.1107/S1600536811032028/hb6352sup1.cif

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536811032028/hb6352Isup2.hkl

Supplementary material file. DOI: 10.1107/S1600536811032028/hb6352Isup3.cml

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

0.6C14H12N2O3·0.4C14H12N2O3	F(000) = 536
Mr = 256.26	Dx = 1.376 Mg m−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 1395 reflections
a = 14.0623 (6) Å	θ = 2.0–25.3°
b = 14.1723 (8) Å	µ = 0.10 mm−1
c = 6.2357 (3) Å	T = 296 K
β = 95.400 (2)°	Prism, yellow
V = 1237.23 (11) Å3	0.25 × 0.22 × 0.20 mm
Z = 4

Bruker Kappa APEXII CCD diffractometer	2238 independent reflections
Radiation source: fine-focus sealed tube	1395 reflections with I > 2σ(I)
graphite	Rint = 0.041
Detector resolution: 8.10 pixels mm-1	θmax = 25.3°, θmin = 2.0°
ω scans	h = −16→16
Absorption correction: multi-scan (SADABS; Bruker, 2005)	k = −17→17
Tmin = 0.976, Tmax = 0.985	l = −7→7
9733 measured reflections

Refinement on F2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.049	H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.133	w = 1/[σ2(Fo2) + (0.0558P)2 + 0.2667P] where P = (Fo2 + 2Fc2)/3
S = 1.03	(Δ/σ)max < 0.001
2238 reflections	Δρmax = 0.20 e Å−3
181 parameters	Δρmin = −0.18 e Å−3
0 restraints	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0052 (14)

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 of F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > σ(F2) is used only for calculating R-factors(gt) 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.

	x	y	z	Uiso*/Ueq	Occ. (<1)
O1	0.18732 (12)	0.66637 (13)	0.3141 (3)	0.0536 (6)
O2	−0.21627 (11)	0.59616 (18)	0.6085 (3)	0.0928 (9)
O3	−0.13153 (11)	0.55621 (14)	0.8965 (3)	0.0676 (7)
N1	0.28626 (12)	0.62025 (13)	0.6653 (3)	0.0406 (6)
N2	−0.13922 (12)	0.58577 (15)	0.7115 (3)	0.0499 (7)
C1	0.37651 (14)	0.62162 (15)	0.7884 (3)	0.0379 (7)
C2	0.45601 (14)	0.59352 (16)	0.6902 (4)	0.0452 (8)
C3	0.54536 (15)	0.59847 (17)	0.8003 (4)	0.0507 (9)
C4	0.55810 (15)	0.63374 (16)	1.0085 (4)	0.0465 (8)
C5	0.47796 (15)	0.66189 (16)	1.1032 (3)	0.0453 (8)
C6	0.38783 (14)	0.65645 (16)	0.9965 (3)	0.0429 (8)
C7	0.65595 (16)	0.6427 (2)	1.1264 (4)	0.0708 (10)
C8	0.20829 (14)	0.60487 (15)	0.7508 (3)	0.0394 (7)
C9	0.11702 (14)	0.61460 (15)	0.6278 (3)	0.0353 (7)
C10	0.11017 (15)	0.64786 (15)	0.4120 (3)	0.0392 (7)
C11	0.01983 (15)	0.66214 (15)	0.3029 (3)	0.0431 (8)
C12	−0.06138 (15)	0.64214 (15)	0.3987 (3)	0.0431 (8)
C13	−0.05334 (14)	0.60742 (15)	0.6096 (3)	0.0382 (7)
C14	0.03375 (13)	0.59379 (15)	0.7226 (3)	0.0365 (7)
H1	0.234 (4)	0.652 (3)	0.390 (10)	0.0643*	0.60 (4)
H2	0.44905	0.57122	0.54928	0.0542*
H3	0.59813	0.57782	0.73398	0.0608*
H5	0.48500	0.68523	1.24322	0.0544*
H6	0.33496	0.67605	1.06375	0.0515*
H7A	0.65363	0.62414	1.27390	0.1061*
H7B	0.67695	0.70705	1.12087	0.1061*
H7C	0.69974	0.60270	1.05983	0.1061*
H8	0.21077	0.58713	0.89483	0.0472*
H11	0.01490	0.68561	0.16300	0.0517*
H12	−0.12117	0.65149	0.32459	0.0517*
H14	0.03733	0.57065	0.86269	0.0438*
H1A	0.274 (5)	0.641 (4)	0.518 (13)	0.0487*	0.40 (4)

	U11	U22	U33	U12	U13	U23
O1	0.0503 (10)	0.0696 (13)	0.0423 (10)	−0.0045 (9)	0.0123 (8)	0.0082 (8)
O2	0.0349 (10)	0.171 (2)	0.0711 (13)	0.0043 (12)	−0.0028 (9)	0.0236 (13)
O3	0.0485 (10)	0.1043 (16)	0.0511 (11)	−0.0035 (9)	0.0110 (8)	0.0189 (10)
N1	0.0362 (10)	0.0452 (12)	0.0407 (11)	0.0013 (8)	0.0053 (8)	0.0002 (9)
N2	0.0361 (10)	0.0681 (14)	0.0454 (12)	−0.0001 (10)	0.0039 (9)	0.0003 (10)
C1	0.0328 (11)	0.0393 (13)	0.0417 (13)	0.0008 (9)	0.0045 (9)	0.0027 (10)
C2	0.0424 (12)	0.0507 (15)	0.0435 (13)	0.0027 (11)	0.0094 (10)	−0.0063 (11)
C3	0.0354 (12)	0.0554 (16)	0.0627 (16)	0.0073 (11)	0.0127 (11)	−0.0019 (12)
C4	0.0390 (12)	0.0473 (15)	0.0524 (14)	0.0023 (10)	0.0008 (10)	0.0044 (12)
C5	0.0457 (13)	0.0513 (15)	0.0391 (12)	0.0015 (11)	0.0044 (10)	−0.0016 (11)
C6	0.0387 (12)	0.0489 (14)	0.0424 (13)	0.0016 (10)	0.0100 (10)	−0.0003 (11)
C7	0.0458 (14)	0.086 (2)	0.0776 (19)	0.0041 (14)	−0.0102 (13)	−0.0008 (16)
C8	0.0398 (12)	0.0403 (14)	0.0383 (12)	0.0014 (10)	0.0053 (10)	0.0032 (10)
C9	0.0350 (11)	0.0356 (12)	0.0351 (12)	−0.0005 (9)	0.0030 (9)	0.0003 (9)
C10	0.0432 (12)	0.0378 (13)	0.0372 (12)	−0.0030 (10)	0.0077 (10)	−0.0014 (10)
C11	0.0537 (14)	0.0440 (14)	0.0309 (11)	−0.0015 (11)	0.0005 (10)	0.0046 (10)
C12	0.0427 (12)	0.0441 (14)	0.0406 (13)	0.0014 (10)	−0.0067 (10)	−0.0023 (10)
C13	0.0351 (11)	0.0422 (14)	0.0378 (12)	−0.0019 (9)	0.0055 (9)	−0.0025 (10)
C14	0.0392 (11)	0.0394 (13)	0.0308 (11)	−0.0002 (10)	0.0029 (9)	0.0007 (9)

O1—C10	1.320 (3)	C9—C10	1.421 (3)
O2—N2	1.215 (2)	C10—C11	1.398 (3)
O3—N2	1.223 (3)	C11—C12	1.367 (3)
O1—H1	0.80 (6)	C12—C13	1.399 (3)
N1—C1	1.420 (3)	C13—C14	1.368 (3)
N1—C8	1.282 (3)	C2—H2	0.9300
N2—C13	1.449 (3)	C3—H3	0.9300
N1—H1A	0.96 (8)	C5—H5	0.9300
C1—C2	1.383 (3)	C6—H6	0.9300
C1—C6	1.384 (3)	C7—H7A	0.9600
C2—C3	1.376 (3)	C7—H7B	0.9600
C3—C4	1.387 (3)	C7—H7C	0.9600
C4—C5	1.380 (3)	C8—H8	0.9300
C4—C7	1.503 (3)	C11—H11	0.9300
C5—C6	1.377 (3)	C12—H12	0.9300
C8—C9	1.439 (3)	C14—H14	0.9300
C9—C14	1.392 (3)
C10—O1—H1	110 (4)	N2—C13—C12	119.32 (18)
C1—N1—C8	122.22 (18)	N2—C13—C14	119.13 (17)
O2—N2—O3	122.38 (18)	C12—C13—C14	121.55 (18)
O3—N2—C13	118.87 (17)	C9—C14—C13	119.96 (18)
O2—N2—C13	118.74 (18)	C1—C2—H2	120.00
C8—N1—H1A	111 (4)	C3—C2—H2	120.00
C1—N1—H1A	126 (4)	C2—C3—H3	119.00
N1—C1—C2	118.38 (18)	C4—C3—H3	119.00
N1—C1—C6	122.00 (18)	C4—C5—H5	119.00
C2—C1—C6	119.45 (19)	C6—C5—H5	119.00
C1—C2—C3	120.2 (2)	C1—C6—H6	120.00
C2—C3—C4	121.1 (2)	C5—C6—H6	120.00
C3—C4—C5	117.8 (2)	C4—C7—H7A	109.00
C3—C4—C7	121.3 (2)	C4—C7—H7B	109.00
C5—C4—C7	120.9 (2)	C4—C7—H7C	109.00
C4—C5—C6	121.92 (19)	H7A—C7—H7B	109.00
C1—C6—C5	119.51 (18)	H7A—C7—H7C	109.00
N1—C8—C9	121.13 (18)	H7B—C7—H7C	109.00
C8—C9—C14	119.82 (17)	N1—C8—H8	119.00
C8—C9—C10	120.96 (18)	C9—C8—H8	119.00
C10—C9—C14	119.20 (18)	C10—C11—H11	119.00
O1—C10—C9	121.23 (19)	C12—C11—H11	119.00
O1—C10—C11	119.66 (18)	C11—C12—H12	120.00
C9—C10—C11	119.11 (18)	C13—C12—H12	120.00
C10—C11—C12	121.02 (18)	C9—C14—H14	120.00
C11—C12—C13	119.13 (19)	C13—C14—H14	120.00
C8—N1—C1—C2	149.4 (2)	C4—C5—C6—C1	0.2 (3)
C8—N1—C1—C6	−35.4 (3)	N1—C8—C9—C10	−4.4 (3)
C1—N1—C8—C9	172.72 (19)	N1—C8—C9—C14	177.4 (2)
O2—N2—C13—C12	1.9 (3)	C8—C9—C10—O1	3.4 (3)
O2—N2—C13—C14	−178.5 (2)	C8—C9—C10—C11	−175.9 (2)
O3—N2—C13—C12	−179.4 (2)	C14—C9—C10—O1	−178.4 (2)
O3—N2—C13—C14	0.3 (3)	C14—C9—C10—C11	2.3 (3)
N1—C1—C2—C3	176.6 (2)	C8—C9—C14—C13	176.8 (2)
C6—C1—C2—C3	1.3 (3)	C10—C9—C14—C13	−1.4 (3)
N1—C1—C6—C5	−175.7 (2)	O1—C10—C11—C12	178.9 (2)
C2—C1—C6—C5	−0.5 (3)	C9—C10—C11—C12	−1.8 (3)
C1—C2—C3—C4	−1.7 (4)	C10—C11—C12—C13	0.4 (3)
C2—C3—C4—C5	1.3 (3)	C11—C12—C13—N2	−179.76 (19)
C2—C3—C4—C7	−177.7 (2)	C11—C12—C13—C14	0.6 (3)
C3—C4—C5—C6	−0.6 (3)	N2—C13—C14—C9	−179.70 (19)
C7—C4—C5—C6	178.4 (2)	C12—C13—C14—C9	0.0 (3)

Cg1 and Cg2 are the centroids of the C1—C6 and C9—C14 rings, respectively.

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1···N1	0.80 (6)	1.86 (6)	2.566 (3)	147 (6)
N1—H1A···O1	0.97 (8)	1.71 (7)	2.566 (3)	146 (6)
C5—H5···Cg1i	0.93	2.84	3.515 (2)	130
C11—H11···Cg2ii	0.93	2.82	3.490 (2)	130

Table 1

Hydrogen-bond geometry (Å, °)

Cg1 and Cg2 are the centroids of the C1—C6 and C9—C14 rings, respectively.

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—H1⋯N1	0.80 (6)	1.86 (6)	2.566 (3)	147 (6)
N1—H1A⋯O1	0.97 (8)	1.71 (7)	2.566 (3)	146 (6)
C5—H5⋯Cg1i	0.93	2.84	3.515 (2)	130
C11—H11⋯Cg2ii	0.93	2.82	3.490 (2)	130

Symmetry codes: (i) ; (ii) .