1,5-Bis(2-methyl-phen-yl)-3-nitro-formazan.

In the title compound, C(15)H(15)N(5)O(2), the nitro O atoms are disordered over two sets of sites with an occupancy ratio of 0.75 (4):0.25 (4). Amine-imine tautomerism is observed in the formazan group. This was evident from the similar C-N bond distances in the formazan [1.319 (2) and 1.332 (3) Å], as well as the distribution of the imine proton in the Fourier difference map which refined to a 0.53 (3):0.47 (3) ratio. C-H⋯O and π-π inter-actions [centroid-centroid distances = 3.4813 (1) and 3.3976 (1) Å] are observed in the crystal packing.

Related literature

For related structures of nitro­formazan derivatives, see: Gilroy et al. (2008 ▶); Mito et al. (1997 ▶) and for a related dithizone structure, see: Laing (1977 ▶). For the synthesis and chemistry of nitro­formazans, see: Pelkis et al. (1957 ▶); Irving (1977 ▶). For DFT and electrochemistry studies of dithizones, see: Von Eschwege & Swarts (2010 ▶); Von Eschwege et al. (2011 ▶).

Experimental

Crystal data

C15H15N5O2

M = 297.32

Orthorhombic,

a = 14.6525 (3) Å

b = 10.2523 (3) Å

c = 19.2425 (4) Å

V = 2890.64 (12) Å3

Z = 8

Mo Kα radiation

μ = 0.10 mm−1

T = 200 K

0.43 × 0.19 × 0.19 mm

Data collection

Bruker APEXII CCD diffractometer

Absorption correction: multi-scan (SADABS; Bruker, 2008 ▶) T min = 0.960, T max = 0.982

24031 measured reflections

3619 independent reflections

2487 reflections with I > 2σ(I)

R int = 0.028

Refinement

R[F 2 > 2σ(F 2)] = 0.060

wR(F 2) = 0.180

S = 1.05

3619 reflections

221 parameters

48 restraints

H-atom parameters constrained

Δρmax = 0.51 e Å−3

Δρmin = −0.21 e Å−3

Data collection: APEX2 (Bruker, 2011 ▶); cell refinement: SAINT (Bruker, 2008 ▶); data reduction: SAINT and XPREP (Bruker, 2008 ▶); program(s) used to solve structure: SIR97 (Altomare et al., 1999 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: DIAMOND (Brandenburg & Putz, 2005 ▶); software used to prepare material for publication: WinGX (Farrugia, 1999 ▶).

Crystal structure: contains datablock(s) global, I. DOI: 10.1107/S1600536812001171/kp2378sup1.cif

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536812001171/kp2378Isup2.hkl

Supplementary material file. DOI: 10.1107/S1600536812001171/kp2378Isup3.cml

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

C15H15N5O2	F(000) = 1248
Mr = 297.32	Dx = 1.366 Mg m−3
Orthorhombic, Pbca	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ac 2ab	Cell parameters from 8384 reflections
a = 14.6525 (3) Å	θ = 2.7–28.3°
b = 10.2523 (3) Å	µ = 0.10 mm−1
c = 19.2425 (4) Å	T = 200 K
V = 2890.64 (12) Å3	Needle, red
Z = 8	0.43 × 0.19 × 0.19 mm

Bruker APEXII CCD diffractometer	3619 independent reflections
graphite	2487 reflections with I > 2σ(I)
Detector resolution: 8.4 pixels mm-1	Rint = 0.028
ω and φ scans	θmax = 28.4°, θmin = 2.1°
Absorption correction: multi-scan (SADABS; Bruker, 2008)	h = −19→19
Tmin = 0.960, Tmax = 0.982	k = −12→13
24031 measured reflections	l = −25→25

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)] = 0.060	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.180	H-atom parameters constrained
S = 1.05	w = 1/[σ2(Fo2) + (0.070P)2 + 1.8629P] where P = (Fo2 + 2Fc2)/3
3619 reflections	(Δ/σ)max < 0.001
221 parameters	Δρmax = 0.51 e Å−3
48 restraints	Δρmin = −0.21 e Å−3

Experimental. The intensity data was collected on a Bruker APEX-II CCD diffractometer using an exposure time of 60 s/frame. A total of 1062 frames were collected with a frame width of 0.5° covering up to θ = 28.40° with 99.6% completeness accomplished.Analytical data: M.p. 154 °C. λmax (dichloromethane) 319, 440 nm. 1H (600 MHz, CDCl3) 14.32 (1 H, 1 × s, 1 × NH), 2.58 (6 H, 1 × s, 2 × CH3), 7.92 – 7.29 (8 H, 2 × m, 2 × C6H4)

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes.

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)
N1	0.26169 (12)	0.01378 (16)	0.07679 (8)	0.0441 (4)
HN1	0.2252	0.0663	0.0999	0.053*	0.53 (3)
N2	0.34854 (12)	0.01558 (17)	0.08281 (8)	0.0458 (4)
N3	0.35427 (11)	0.19544 (16)	0.16744 (8)	0.0408 (4)
N4	0.26631 (10)	0.21162 (16)	0.17126 (8)	0.0385 (4)
HN4	0.2283	0.1648	0.1462	0.046*	0.47 (3)
N5	0.48561 (13)	0.0936 (2)	0.12737 (11)	0.0580 (5)
O1A	0.5222 (5)	−0.0056 (8)	0.1083 (9)	0.094 (3)	0.75 (4)
O2A	0.5302 (5)	0.1873 (10)	0.1454 (10)	0.087 (3)	0.75 (4)
O1B	0.512 (2)	0.012 (3)	0.087 (2)	0.107 (8)	0.25 (4)
O2B	0.5218 (19)	0.155 (4)	0.172 (2)	0.097 (6)	0.25 (4)
C1	0.07297 (15)	−0.0431 (3)	0.07535 (13)	0.0596 (6)
H1A	0.092	−0.0557	0.1237	0.089*
H1B	0.0118	−0.0797	0.0687	0.089*
H1C	0.072	0.0503	0.0646	0.089*
C2	0.13763 (15)	−0.1095 (2)	0.02891 (10)	0.0485 (5)
C3	0.10754 (17)	−0.2092 (2)	−0.01616 (11)	0.0549 (6)
H3	0.0448	−0.2327	−0.0162	0.066*
C4	0.16569 (18)	−0.2723 (2)	−0.05938 (12)	0.0590 (6)
H4	0.1436	−0.3392	−0.0891	0.071*
C5	0.25748 (19)	−0.2394 (2)	−0.06022 (12)	0.0629 (6)
H5	0.2978	−0.2822	−0.0915	0.075*
C6	0.28997 (16)	−0.1465 (2)	−0.01666 (11)	0.0543 (5)
H6	0.353	−0.1251	−0.0169	0.065*
C7	0.22993 (15)	−0.0819 (2)	0.02888 (10)	0.0464 (5)
C8	0.38492 (13)	0.1033 (2)	0.12568 (9)	0.0425 (4)
C9	0.23522 (12)	0.30827 (18)	0.21773 (9)	0.0375 (4)
C10	0.29585 (14)	0.3870 (2)	0.25478 (10)	0.0448 (5)
H10	0.3598	0.3751	0.2496	0.054*
C11	0.26305 (16)	0.4823 (2)	0.29902 (10)	0.0501 (5)
H11	0.3043	0.5367	0.3238	0.06*
C12	0.16987 (16)	0.4981 (2)	0.30707 (11)	0.0510 (5)
H12	0.1469	0.5632	0.3375	0.061*
C13	0.11046 (15)	0.4192 (2)	0.27091 (11)	0.0511 (5)
H13	0.0467	0.431	0.2771	0.061*
C14	0.14087 (13)	0.3228 (2)	0.22551 (10)	0.0429 (4)
C15	0.07500 (14)	0.2388 (3)	0.18674 (14)	0.0619 (6)
H15A	0.0125	0.2619	0.2001	0.093*
H15B	0.0864	0.147	0.198	0.093*
H15C	0.0829	0.2523	0.1367	0.093*

	U11	U22	U33	U12	U13	U23
N1	0.0552 (10)	0.0391 (9)	0.0381 (8)	−0.0027 (7)	−0.0009 (7)	0.0037 (7)
N2	0.0527 (9)	0.0440 (9)	0.0405 (8)	0.0019 (8)	0.0020 (7)	0.0042 (7)
N3	0.0402 (8)	0.0431 (9)	0.0392 (8)	0.0031 (7)	0.0009 (6)	0.0042 (7)
N4	0.0381 (8)	0.0405 (9)	0.0369 (7)	0.0013 (6)	0.0012 (6)	0.0042 (6)
N5	0.0436 (10)	0.0637 (13)	0.0666 (12)	0.0095 (9)	0.0059 (9)	−0.0043 (10)
O1A	0.045 (2)	0.070 (3)	0.168 (7)	0.0139 (19)	0.001 (3)	−0.030 (3)
O2A	0.0410 (16)	0.094 (4)	0.125 (6)	−0.0035 (18)	−0.004 (3)	−0.048 (4)
O1B	0.085 (11)	0.124 (13)	0.112 (14)	0.049 (10)	0.039 (9)	−0.025 (9)
O2B	0.049 (7)	0.141 (14)	0.101 (12)	−0.003 (8)	−0.011 (8)	−0.027 (11)
C1	0.0484 (12)	0.0678 (15)	0.0626 (13)	−0.0005 (11)	−0.0058 (10)	−0.0057 (12)
C2	0.0552 (12)	0.0461 (12)	0.0440 (10)	0.0007 (9)	0.0014 (9)	0.0074 (9)
C3	0.0651 (13)	0.0518 (13)	0.0479 (11)	−0.0098 (11)	−0.0066 (10)	0.0042 (10)
C4	0.0763 (15)	0.0480 (13)	0.0528 (12)	−0.0119 (11)	−0.0020 (11)	−0.0008 (10)
C5	0.0755 (16)	0.0577 (14)	0.0555 (13)	−0.0040 (12)	0.0140 (12)	−0.0069 (11)
C6	0.0601 (13)	0.0548 (13)	0.0481 (11)	−0.0088 (10)	0.0075 (9)	−0.0021 (10)
C7	0.0567 (12)	0.0431 (11)	0.0394 (9)	−0.0034 (9)	−0.0013 (8)	0.0056 (8)
C8	0.0400 (9)	0.0454 (11)	0.0420 (9)	0.0042 (8)	0.0020 (8)	0.0043 (8)
C9	0.0431 (9)	0.0360 (9)	0.0334 (8)	0.0018 (7)	0.0008 (7)	0.0066 (7)
C10	0.0465 (10)	0.0472 (11)	0.0407 (9)	−0.0020 (9)	−0.0003 (8)	0.0031 (8)
C11	0.0625 (13)	0.0466 (12)	0.0413 (10)	−0.0026 (10)	−0.0034 (9)	0.0009 (9)
C12	0.0644 (13)	0.0438 (12)	0.0449 (11)	0.0059 (10)	0.0036 (9)	−0.0019 (9)
C13	0.0495 (11)	0.0474 (12)	0.0564 (12)	0.0082 (9)	0.0065 (9)	0.0001 (10)
C14	0.0438 (10)	0.0404 (10)	0.0445 (10)	0.0035 (8)	0.0008 (8)	0.0029 (8)
C15	0.0408 (10)	0.0639 (15)	0.0811 (16)	0.0020 (10)	−0.0016 (10)	−0.0208 (13)

N1—N2	1.278 (2)	C4—C5	1.387 (4)
N1—C7	1.424 (3)	C4—H4	0.95
N1—HN1	0.88	C5—C6	1.355 (3)
N2—C8	1.332 (3)	C5—H5	0.95
N3—N4	1.302 (2)	C6—C7	1.407 (3)
N3—C8	1.319 (2)	C6—H6	0.95
N4—C9	1.410 (2)	C9—C10	1.396 (3)
N4—HN4	0.88	C9—C14	1.399 (3)
N5—O2B	1.192 (13)	C10—C11	1.382 (3)
N5—O1A	1.208 (5)	C10—H10	0.95
N5—O1B	1.210 (13)	C11—C12	1.384 (3)
N5—O2A	1.212 (6)	C11—H11	0.95
N5—C8	1.479 (3)	C12—C13	1.377 (3)
C1—C2	1.470 (3)	C12—H12	0.95
C1—H1A	0.98	C13—C14	1.392 (3)
C1—H1B	0.98	C13—H13	0.95
C1—H1C	0.98	C14—C15	1.494 (3)
C2—C7	1.382 (3)	C15—H15A	0.98
C2—C3	1.411 (3)	C15—H15B	0.98
C3—C4	1.355 (3)	C15—H15C	0.98
C3—H3	0.95
N2—N1—C7	113.21 (17)	C5—C6—C7	119.8 (2)
N2—N1—HN1	123.4	C5—C6—H6	120.1
C7—N1—HN1	123.4	C7—C6—H6	120.1
N1—N2—C8	117.68 (17)	C2—C7—C6	121.0 (2)
N4—N3—C8	117.57 (16)	C2—C7—N1	117.44 (19)
N3—N4—C9	116.44 (15)	C6—C7—N1	121.53 (19)
N3—N4—HN4	121.8	N3—C8—N2	136.45 (18)
C9—N4—HN4	121.8	N3—C8—N5	111.97 (17)
O2B—N5—O1A	117.8 (14)	N2—C8—N5	111.57 (17)
O2B—N5—O1B	134 (2)	C10—C9—C14	120.83 (18)
O1A—N5—O2A	121.0 (5)	C10—C9—N4	121.64 (17)
O1B—N5—O2A	124.2 (14)	C14—C9—N4	117.53 (16)
O2B—N5—C8	115.1 (14)	C11—C10—C9	120.14 (19)
O1A—N5—C8	119.5 (4)	C11—C10—H10	119.9
O1B—N5—C8	110.4 (16)	C9—C10—H10	119.9
O2A—N5—C8	119.4 (4)	C10—C11—C12	119.6 (2)
C2—C1—H1A	109.5	C10—C11—H11	120.2
C2—C1—H1B	109.5	C12—C11—H11	120.2
H1A—C1—H1B	109.5	C13—C12—C11	119.9 (2)
C2—C1—H1C	109.5	C13—C12—H12	120
H1A—C1—H1C	109.5	C11—C12—H12	120
H1B—C1—H1C	109.5	C12—C13—C14	122.1 (2)
C7—C2—C3	117.0 (2)	C12—C13—H13	118.9
C7—C2—C1	122.4 (2)	C14—C13—H13	118.9
C3—C2—C1	120.5 (2)	C13—C14—C9	117.34 (18)
C4—C3—C2	121.8 (2)	C13—C14—C15	121.07 (19)
C4—C3—H3	119.1	C9—C14—C15	121.59 (18)
C2—C3—H3	119.1	C14—C15—H15A	109.5
C3—C4—C5	120.0 (2)	C14—C15—H15B	109.5
C3—C4—H4	120	H15A—C15—H15B	109.5
C5—C4—H4	120	C14—C15—H15C	109.5
C6—C5—C4	120.3 (2)	H15A—C15—H15C	109.5
C6—C5—H5	119.8	H15B—C15—H15C	109.5
C4—C5—H5	119.8
C7—N1—N2—C8	178.96 (16)	O1A—N5—C8—N3	159.5 (10)
C8—N3—N4—C9	178.28 (15)	O1B—N5—C8—N3	−177 (2)
C7—C2—C3—C4	−2.2 (3)	O2A—N5—C8—N3	−23.3 (11)
C1—C2—C3—C4	−179.8 (2)	O2B—N5—C8—N2	−169 (3)
C2—C3—C4—C5	−0.1 (4)	O1A—N5—C8—N2	−19.9 (10)
C3—C4—C5—C6	1.7 (4)	O1B—N5—C8—N2	3(2)
C4—C5—C6—C7	−0.9 (4)	O2A—N5—C8—N2	157.4 (11)
C3—C2—C7—C6	3.0 (3)	N3—N4—C9—C10	3.3 (2)
C1—C2—C7—C6	−179.5 (2)	N3—N4—C9—C14	−176.70 (16)
C3—C2—C7—N1	−176.77 (17)	C14—C9—C10—C11	−1.0 (3)
C1—C2—C7—N1	0.8 (3)	N4—C9—C10—C11	178.91 (17)
C5—C6—C7—C2	−1.5 (3)	C9—C10—C11—C12	0.8 (3)
C5—C6—C7—N1	178.3 (2)	C10—C11—C12—C13	−0.2 (3)
N2—N1—C7—C2	167.38 (17)	C11—C12—C13—C14	−0.3 (3)
N2—N1—C7—C6	−12.4 (3)	C12—C13—C14—C9	0.1 (3)
N4—N3—C8—N2	0.3 (3)	C12—C13—C14—C15	−179.8 (2)
N4—N3—C8—N5	−178.83 (16)	C10—C9—C14—C13	0.6 (3)
N1—N2—C8—N3	0.8 (3)	N4—C9—C14—C13	−179.37 (16)
N1—N2—C8—N5	179.90 (16)	C10—C9—C14—C15	−179.5 (2)
O2B—N5—C8—N3	11 (3)	N4—C9—C14—C15	0.5 (3)

D—H···A	D—H	H···A	D···A	D—H···A
C4—H4···O1Ai	0.95	2.42	3.239 (9)	145

Cg(X)···Cg(Y)	Cg···Cg	Alpha	Beta	Gamma	Cg(X)perp	Cg(X)perp
Cg1···Cg2i	3.4813	7.215	4.85	12.04	3.4047	-3.4688
Cg1···Cg3i	3.3976	2.589	3.11	3.37	-3.3917	3.3925

Table 1

Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C4—H4⋯O1Ai	0.95	2.42	3.239 (9)	145

Symmetry code: (i) .