2,2-Dimethyl-N,N'-bis-(4-nitro-benzyl-idene)propane-1,3-diamine.

In the title compound, C(19)H(20)N(4)O(4), a potential bidentate Schiff base ligand, each imino (C=N) functional group is coplanar with the adjacent benzene ring. The two benzene rings form a dihedral angle of 10.52 (6)°. Inter-molecular C-H⋯O contacts link neighbouring mol-ecules into supra-molecular array with an R(2) (2)(32) ring motif and a C-H⋯π contact is also present.

Related literature

For details of hydrogen-bond motifs, see: Bernstein et al. (1995 ▶). For related structures, see: Li et al. (2005 ▶); Bomfim et al. (2005 ▶); Glidewell et al. (2005 ▶, 2006 ▶); Sun et al. (2004 ▶); Fun et al. (2008a ▶,b ▶).

Experimental

Crystal data

C19H20N4O4

M = 368.39

Monoclinic,

a = 7.8219 (1) Å

b = 19.9716 (4) Å

c = 12.0125 (3) Å

β = 92.831 (1)°

V = 1874.25 (6) Å3

Z = 4

Mo Kα radiation

μ = 0.09 mm−1

T = 100 (1) K

0.45 × 0.19 × 0.08 mm

Data collection

Bruker SMART APEXII CCD area-detector diffractometer

Absorption correction: multi-scan (; Bruker, 2005 ▶) T min = 0.959, T max = 0.993

21845 measured reflections

6784 independent reflections

4307 reflections with I > 2σ(I)

R int = 0.048

Refinement

R[F 2 > 2σ(F 2)] = 0.061

wR(F 2) = 0.152

S = 1.04

6784 reflections

244 parameters

H-atom parameters constrained

Δρmax = 0.36 e Å−3

Δρmin = −0.23 e Å−3

Data collection: APEX2 (Bruker, 2005 ▶); cell refinement: SAINT (Bruker, 2005 ▶); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2003 ▶).

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536808037033/tk2324sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536808037033/tk2324Isup2.hkl

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

C19H20N4O4	F000 = 776
Mr = 368.39	Dx = 1.306 Mg m−3
Monoclinic, P21/c	Mo Kα radiation λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 3284 reflections
a = 7.8219 (1) Å	θ = 2.7–28.9º
b = 19.9716 (4) Å	µ = 0.09 mm−1
c = 12.0125 (3) Å	T = 100 (1) K
β = 92.831 (1)º	Block, colourless
V = 1874.25 (6) Å3	0.45 × 0.19 × 0.08 mm
Z = 4

Bruker SMART APEXII CCD area-detector diffractometer	6784 independent reflections
Radiation source: fine-focus sealed tube	4307 reflections with I > 2σ(I)
Monochromator: graphite	Rint = 0.048
T = 100(1) K	θmax = 32.6º
φ and ω scans	θmin = 2.0º
Absorption correction: multi-scan(SADABS; Bruker, 2005)	h = −11→11
Tmin = 0.959, Tmax = 0.993	k = −30→24
21845 measured reflections	l = −16→18

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)] = 0.061	H-atom parameters constrained
wR(F2) = 0.152	w = 1/[σ2(Fo2) + (0.063P)2 + 0.2454P] where P = (Fo2 + 2Fc2)/3
S = 1.04	(Δ/σ)max < 0.001
6784 reflections	Δρmax = 0.36 e Å−3
244 parameters	Δρmin = −0.23 e Å−3
Primary atom site location: structure-invariant direct methods	Extinction correction: none

Experimental. The low-temperature data was collected with the Oxford Cyrosystem Cobra low-temperature attachment.

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
O1	1.36590 (14)	0.55914 (6)	0.45685 (10)	0.0335 (3)
O2	1.36634 (15)	0.48567 (6)	0.32431 (10)	0.0376 (3)
O3	0.04816 (14)	0.42804 (6)	1.17606 (9)	0.0317 (3)
O4	0.13096 (14)	0.52456 (5)	1.11560 (10)	0.0313 (3)
N1	0.91963 (15)	0.26572 (6)	0.65265 (11)	0.0229 (3)
N2	0.44695 (14)	0.27677 (6)	0.73309 (11)	0.0232 (3)
N3	1.32746 (15)	0.50399 (7)	0.41710 (12)	0.0263 (3)
N4	0.12292 (14)	0.46308 (6)	1.10932 (10)	0.0240 (3)
C1	1.07594 (17)	0.43692 (7)	0.64720 (12)	0.0214 (3)
H1A	1.0348	0.4512	0.7146	0.026*
C2	1.17251 (17)	0.48038 (7)	0.58500 (12)	0.0222 (3)
H2A	1.1983	0.5234	0.6103	0.027*
C3	1.22894 (16)	0.45767 (7)	0.48441 (12)	0.0212 (3)
C4	1.19437 (18)	0.39416 (8)	0.44352 (13)	0.0254 (3)
H4A	1.2337	0.3806	0.3753	0.031*
C5	1.09965 (17)	0.35135 (7)	0.50692 (13)	0.0245 (3)
H5A	1.0751	0.3083	0.4813	0.029*
C6	1.04054 (16)	0.37232 (7)	0.60928 (12)	0.0195 (3)
C7	0.94133 (16)	0.32672 (7)	0.67822 (12)	0.0205 (3)
H7A	0.8936	0.3432	0.7421	0.025*
C8	0.81845 (17)	0.22410 (7)	0.72454 (12)	0.0220 (3)
H8A	0.7833	0.2506	0.7871	0.026*
H8B	0.8885	0.1874	0.7537	0.026*
C9	0.65824 (17)	0.19558 (7)	0.66089 (12)	0.0211 (3)
C10	0.52727 (18)	0.25158 (7)	0.63434 (13)	0.0228 (3)
H10A	0.5843	0.2883	0.5986	0.027*
H10B	0.4391	0.2346	0.5821	0.027*
C11	0.44070 (16)	0.33980 (7)	0.74535 (12)	0.0211 (3)
H11A	0.4901	0.3673	0.6933	0.025*
C12	0.35718 (16)	0.37059 (7)	0.83998 (12)	0.0192 (3)
C13	0.25521 (16)	0.33267 (7)	0.90909 (12)	0.0214 (3)
H13A	0.2384	0.2873	0.8946	0.026*
C14	0.17916 (17)	0.36202 (7)	0.99872 (12)	0.0222 (3)
H14A	0.1125	0.3369	1.0453	0.027*
C15	0.20531 (16)	0.43004 (7)	1.01696 (12)	0.0203 (3)
C16	0.30321 (16)	0.46938 (7)	0.94913 (12)	0.0210 (3)
H16A	0.3173	0.5149	0.9627	0.025*
C17	0.37936 (17)	0.43876 (7)	0.86057 (12)	0.0215 (3)
H17A	0.4461	0.4641	0.8143	0.026*
C18	0.58134 (19)	0.14167 (8)	0.73376 (14)	0.0289 (3)
H18A	0.4811	0.1232	0.6959	0.043*
H18B	0.5507	0.1611	0.8031	0.043*
H18C	0.6639	0.1068	0.7481	0.043*
C19	0.70671 (19)	0.16493 (7)	0.54990 (13)	0.0259 (3)
H19A	0.6059	0.1477	0.5111	0.039*
H19B	0.7870	0.1292	0.5638	0.039*
H19C	0.7577	0.1987	0.5052	0.039*

	U11	U22	U33	U12	U13	U23
O1	0.0318 (6)	0.0268 (6)	0.0423 (7)	−0.0069 (5)	0.0043 (5)	0.0051 (5)
O2	0.0377 (6)	0.0447 (7)	0.0314 (7)	−0.0070 (5)	0.0128 (5)	0.0041 (5)
O3	0.0332 (6)	0.0354 (6)	0.0276 (6)	−0.0072 (5)	0.0108 (5)	−0.0019 (5)
O4	0.0381 (6)	0.0230 (6)	0.0334 (7)	0.0044 (4)	0.0082 (5)	−0.0026 (5)
N1	0.0213 (5)	0.0232 (6)	0.0244 (7)	−0.0026 (4)	0.0020 (5)	−0.0003 (5)
N2	0.0211 (5)	0.0225 (6)	0.0261 (7)	0.0004 (4)	0.0023 (5)	−0.0012 (5)
N3	0.0185 (5)	0.0297 (7)	0.0308 (7)	−0.0009 (5)	0.0019 (5)	0.0075 (6)
N4	0.0202 (5)	0.0280 (7)	0.0238 (7)	0.0009 (5)	0.0024 (5)	−0.0016 (5)
C1	0.0197 (6)	0.0234 (7)	0.0211 (7)	0.0017 (5)	0.0010 (5)	−0.0015 (6)
C2	0.0197 (6)	0.0212 (7)	0.0255 (8)	−0.0003 (5)	−0.0016 (5)	−0.0005 (6)
C3	0.0162 (6)	0.0235 (7)	0.0240 (7)	0.0008 (5)	0.0021 (5)	0.0055 (6)
C4	0.0255 (7)	0.0286 (8)	0.0229 (8)	−0.0007 (6)	0.0076 (6)	−0.0018 (6)
C5	0.0254 (7)	0.0228 (7)	0.0257 (8)	−0.0011 (5)	0.0051 (6)	−0.0037 (6)
C6	0.0173 (6)	0.0204 (6)	0.0207 (7)	0.0001 (5)	0.0011 (5)	0.0007 (5)
C7	0.0187 (6)	0.0234 (7)	0.0196 (7)	−0.0003 (5)	0.0018 (5)	−0.0004 (6)
C8	0.0239 (6)	0.0208 (7)	0.0215 (7)	−0.0013 (5)	0.0020 (5)	0.0012 (6)
C9	0.0218 (6)	0.0177 (6)	0.0238 (7)	−0.0015 (5)	0.0013 (5)	−0.0003 (6)
C10	0.0241 (6)	0.0216 (7)	0.0227 (8)	0.0002 (5)	0.0002 (5)	−0.0019 (6)
C11	0.0195 (6)	0.0219 (7)	0.0220 (7)	−0.0001 (5)	0.0018 (5)	0.0010 (6)
C12	0.0170 (6)	0.0200 (6)	0.0204 (7)	0.0021 (5)	−0.0001 (5)	0.0015 (5)
C13	0.0195 (6)	0.0179 (6)	0.0268 (8)	−0.0007 (5)	0.0015 (5)	0.0002 (6)
C14	0.0192 (6)	0.0229 (7)	0.0248 (8)	0.0000 (5)	0.0036 (5)	0.0046 (6)
C15	0.0180 (6)	0.0228 (7)	0.0201 (7)	0.0024 (5)	0.0010 (5)	−0.0002 (5)
C16	0.0207 (6)	0.0180 (6)	0.0242 (7)	0.0002 (5)	0.0007 (5)	0.0003 (6)
C17	0.0207 (6)	0.0211 (7)	0.0229 (7)	−0.0005 (5)	0.0027 (5)	0.0031 (6)
C18	0.0282 (7)	0.0228 (7)	0.0357 (9)	−0.0041 (6)	0.0025 (6)	0.0048 (7)
C19	0.0275 (7)	0.0212 (7)	0.0289 (8)	0.0011 (5)	−0.0008 (6)	−0.0045 (6)

O1—N3	1.2319 (17)	C8—H8B	0.9700
O2—N3	1.2256 (17)	C9—C18	1.530 (2)
O3—N4	1.2330 (15)	C9—C19	1.532 (2)
O4—N4	1.2316 (16)	C9—C10	1.539 (2)
N1—C7	1.2657 (18)	C10—H10A	0.9700
N1—C8	1.4597 (17)	C10—H10B	0.9700
N2—C11	1.2687 (18)	C11—C12	1.4732 (19)
N2—C10	1.4591 (18)	C11—H11A	0.9300
N3—C3	1.4714 (18)	C12—C17	1.3931 (19)
N4—C15	1.4671 (18)	C12—C13	1.4014 (18)
C1—C6	1.3914 (19)	C13—C14	1.3857 (19)
C1—C2	1.3921 (19)	C13—H13A	0.9300
C1—H1A	0.9300	C14—C15	1.389 (2)
C2—C3	1.383 (2)	C14—H14A	0.9300
C2—H2A	0.9300	C15—C16	1.3890 (18)
C3—C4	1.382 (2)	C16—C17	1.3868 (19)
C4—C5	1.3840 (19)	C16—H16A	0.9300
C4—H4A	0.9300	C17—H17A	0.9300
C5—C6	1.3990 (19)	C18—H18A	0.9600
C5—H5A	0.9300	C18—H18B	0.9600
C6—C7	1.4768 (18)	C18—H18C	0.9600
C7—H7A	0.9300	C19—H19A	0.9600
C8—C9	1.544 (2)	C19—H19B	0.9600
C8—H8A	0.9700	C19—H19C	0.9600
C7—N1—C8	118.34 (12)	C10—C9—C8	110.49 (11)
C11—N2—C10	117.20 (12)	N2—C10—C9	113.01 (12)
O2—N3—O1	123.55 (13)	N2—C10—H10A	109.0
O2—N3—C3	118.19 (13)	C9—C10—H10A	109.0
O1—N3—C3	118.26 (13)	N2—C10—H10B	109.0
O4—N4—O3	123.39 (12)	C9—C10—H10B	109.0
O4—N4—C15	118.14 (12)	H10A—C10—H10B	107.8
O3—N4—C15	118.47 (12)	N2—C11—C12	121.65 (13)
C6—C1—C2	120.46 (13)	N2—C11—H11A	119.2
C6—C1—H1A	119.8	C12—C11—H11A	119.2
C2—C1—H1A	119.8	C17—C12—C13	119.50 (12)
C3—C2—C1	118.00 (13)	C17—C12—C11	119.26 (12)
C3—C2—H2A	121.0	C13—C12—C11	121.24 (12)
C1—C2—H2A	121.0	C14—C13—C12	120.69 (13)
C4—C3—C2	123.10 (13)	C14—C13—H13A	119.7
C4—C3—N3	118.70 (13)	C12—C13—H13A	119.7
C2—C3—N3	118.18 (13)	C13—C14—C15	118.07 (12)
C3—C4—C5	118.16 (13)	C13—C14—H14A	121.0
C3—C4—H4A	120.9	C15—C14—H14A	121.0
C5—C4—H4A	120.9	C16—C15—C14	122.80 (13)
C4—C5—C6	120.52 (14)	C16—C15—N4	117.69 (12)
C4—C5—H5A	119.7	C14—C15—N4	119.48 (12)
C6—C5—H5A	119.7	C17—C16—C15	118.07 (13)
C1—C6—C5	119.75 (13)	C17—C16—H16A	121.0
C1—C6—C7	119.33 (12)	C15—C16—H16A	121.0
C5—C6—C7	120.92 (13)	C16—C17—C12	120.85 (12)
N1—C7—C6	121.69 (13)	C16—C17—H17A	119.6
N1—C7—H7A	119.2	C12—C17—H17A	119.6
C6—C7—H7A	119.2	C9—C18—H18A	109.5
N1—C8—C9	111.56 (12)	C9—C18—H18B	109.5
N1—C8—H8A	109.3	H18A—C18—H18B	109.5
C9—C8—H8A	109.3	C9—C18—H18C	109.5
N1—C8—H8B	109.3	H18A—C18—H18C	109.5
C9—C8—H8B	109.3	H18B—C18—H18C	109.5
H8A—C8—H8B	108.0	C9—C19—H19A	109.5
C18—C9—C19	109.76 (12)	C9—C19—H19B	109.5
C18—C9—C10	110.70 (11)	H19A—C19—H19B	109.5
C19—C9—C10	107.51 (12)	C9—C19—H19C	109.5
C18—C9—C8	107.98 (12)	H19A—C19—H19C	109.5
C19—C9—C8	110.41 (11)	H19B—C19—H19C	109.5
C6—C1—C2—C3	1.0 (2)	C11—N2—C10—C9	131.95 (13)
C1—C2—C3—C4	−0.2 (2)	C18—C9—C10—N2	49.59 (16)
C1—C2—C3—N3	178.53 (12)	C19—C9—C10—N2	169.47 (11)
O2—N3—C3—C4	4.2 (2)	C8—C9—C10—N2	−69.98 (14)
O1—N3—C3—C4	−176.02 (13)	C10—N2—C11—C12	177.85 (12)
O2—N3—C3—C2	−174.58 (13)	N2—C11—C12—C17	168.88 (14)
O1—N3—C3—C2	5.17 (19)	N2—C11—C12—C13	−11.5 (2)
C2—C3—C4—C5	−0.4 (2)	C17—C12—C13—C14	−1.2 (2)
N3—C3—C4—C5	−179.16 (13)	C11—C12—C13—C14	179.15 (13)
C3—C4—C5—C6	0.2 (2)	C12—C13—C14—C15	0.8 (2)
C2—C1—C6—C5	−1.2 (2)	C13—C14—C15—C16	0.3 (2)
C2—C1—C6—C7	178.54 (12)	C13—C14—C15—N4	178.38 (13)
C4—C5—C6—C1	0.6 (2)	O4—N4—C15—C16	6.84 (19)
C4—C5—C6—C7	−179.19 (13)	O3—N4—C15—C16	−173.73 (12)
C8—N1—C7—C6	−179.39 (12)	O4—N4—C15—C14	−171.35 (13)
C1—C6—C7—N1	−173.22 (14)	O3—N4—C15—C14	8.09 (19)
C5—C6—C7—N1	6.5 (2)	C14—C15—C16—C17	−0.9 (2)
C7—N1—C8—C9	118.97 (14)	N4—C15—C16—C17	−179.01 (12)
N1—C8—C9—C18	168.26 (11)	C15—C16—C17—C12	0.4 (2)
N1—C8—C9—C19	48.27 (15)	C13—C12—C17—C16	0.6 (2)
N1—C8—C9—C10	−70.53 (14)	C11—C12—C17—C16	−179.76 (13)

D—H···A	D—H	H···A	D···A	D—H···A
C1—H1A···O4i	0.93	2.52	3.4330 (18)	168
C17—H17A···O2ii	0.93	2.48	3.4063 (18)	171
C19—H19A···Cg1iii	0.96	2.86	3.8058 (16)	171

Table 1

Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C1—H1A⋯O4i	0.93	2.52	3.4330 (18)	168
C17—H17A⋯O2ii	0.93	2.48	3.4063 (18)	171
C19—H19A⋯Cg1iii	0.96	2.86	3.8058 (16)	171

Symmetry codes: (i) ; (ii) ; (iii) . Cg1 is the centroid of the C12–C17 benzene ring.