4-Isopropyl­amino-3-nitro­benzonitrile

In the title compound, C₁₀H₁₁N₃O₂, the nitro group is essentially coplanar with the aromatic ring [dihedral angle = 3.4 (3)°] and forms an intra­molecular N—H...O hydrogen bond with the amine group. In the crystal, weak aromatic C—H...O and C—H...N hydrogen bonds link the mol­ecules. Weak aromatic ring π–π inter­actions [minimum ring centroid–centroid separation = 3.9841 (16) Å] are also present.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.050
• wR factor = 0.170
• Data-to-parameter ratio = 14.1

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT242_ALERT_2_C Check Low       Ueq as Compared to Neighbors for         C8

Alert level G
PLAT005_ALERT_5_G No _iucr_refine_instructions_details in CIF ....          ?
PLAT128_ALERT_4_G Alternate Setting of Space-group P21/c   .......      P21/n
PLAT199_ALERT_1_G Check the Reported _cell_measurement_temperature        293 K
PLAT200_ALERT_1_G Check the Reported   _diffrn_ambient_temperature        293 K
PLAT371_ALERT_2_G Long   C(sp2)-C(sp1) Bond  C6     -   C7     ...       1.43 Ang.

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

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

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S1. Comment

We report herein the crystal structure of the title compound C₁₀H₁₁N₃O₂. In this molecule (Fig. 1), the bond lengths and angles (Allen et al., 1987) are within normal ranges. The nitro group is essentially coplanar with the aromatic ring forming a dihedral angle of 3.4 (3)° with the ring. The amine H atom forms an intramolecular hydrogen bond with a nitro O-atom acceptor (O2) (Table 1). In the crystal structure, intermolecular aromatic C—H···O and C—H···N hydrogen bonds link the molecules (Fig. 2) while also present are weak aromatic ring π–π interactions [minimum ring centroid separation, 3.9841 (16) Å].

Related literature

For the synthesis of the title compound, see: Ates-Alagoz & Buyukbingol (2001). For bond-length data, see: Allen et al. (1987).

S2. Experimental

The title compound was synthesized using the procedure of (Ates-Alagoz & Buyukbingol, 2001). 4-Chloro-3-nitrobenzonitrile (4.2 g, 0.023 mol) was refluxed in 25 ml of t-propylamine and 50 ml of tetrahydrofuran for 4 h. The solvent was then evaporated and water was added to give a precipitate which was collected by filtration and washed with cold ethanol (2 × 15 ml) to afford the yellow solid (4.2 g, 89%). The pure title compound was obtained by crystallizing from ethanol, with crystals suitable for X-ray diffraction obtained by slow room-temperature evaporation of an ethanol solution.

S3. Refinement

Hydrogen atoms were positioned geometrically, with C—H = 0.93 Å (aromatic), 0.97 Å (methylene) or 0.96 Å (methyl) and N—H = 0.86 Å, an were allowed to ride on their parent atoms, with U_iso(H) = 1.2U_eq(N, aromatic or methylene C) or 1.5U_eq(methyl C).

Computing details

Data collection: CAD-4 Software (Enraf–Nonius, 1994); cell refinement: CAD-4 Software (Enraf–Nonius, 1994); data reduction: XCAD4 (Harms & Wocadlo, 1995); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008.

Figures

	Fig. 1. The molecular structure of the title compound showing the atom-numbering scheme, with displacement ellipsoids drawn at the 30% probability level.
	Fig. 2. A packing diagram of the title compound, with intermolecular hydrogen bonds shown as dashed lines.

4-Isopropylamino-3-nitrobenzonitrile

Crystal data

C10H11N3O2	F(000) = 432
Mr = 205.22	Dx = 1.303 Mg m^−3
Monoclinic, P21/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 25 reflections
a = 6.6640 (13) Å	θ = 9–13°
b = 20.678 (4) Å	µ = 0.09 mm^−1
c = 7.8900 (16) Å	T = 293 K
β = 105.74 (3)°	Block, yellow
V = 1046.5 (4) Å^3	0.20 × 0.10 × 0.10 mm
Z = 4

Data collection

Enraf–Nonius CAD-4 four-circle diffractometer	1228 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.020
Graphite monochromator	θmax = 25.4°, θmin = 2.0°
ω/2θ scans	h = 0→8
Absorption correction: ψ scan (North et al., 1968)	k = −6→24
Tmin = 0.982, Tmax = 0.991	l = −9→9
2821 measured reflections	3 standard reflections every 200 reflections
1926 independent reflections	intensity decay: 1%

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F^2 > 2σ(F^2)] = 0.050	H-atom parameters constrained
wR(F^2) = 0.170	w = 1/[σ^2(Fo^2) + (0.10P)^2 + 0.040P] where P = (Fo^2 + 2Fc^2)/3
S = 1.00	(Δ/σ)max < 0.001
1926 reflections	Δρmax = 0.20 e Å^−3
137 parameters	Δρmin = −0.17 e Å^−3
0 restraints	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.038 (8)

Special details

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
C1	0.3856 (4)	0.06884 (12)	0.1995 (3)	0.0484 (6)
H1A	0.3429	0.0582	0.0805	0.058*
O1	0.6054 (3)	0.10761 (14)	−0.0153 (2)	0.1029 (10)
N1	−0.0699 (4)	−0.01652 (13)	0.2024 (3)	0.0764 (8)
O2	0.8456 (3)	0.15107 (10)	0.1884 (2)	0.0683 (6)
N2	0.6789 (3)	0.12211 (12)	0.1391 (2)	0.0578 (6)
C2	0.5671 (3)	0.10375 (11)	0.2650 (3)	0.0440 (6)
N3	0.8123 (3)	0.15551 (10)	0.5144 (2)	0.0526 (6)
H3A	0.8880	0.1652	0.4454	0.063*
C3	0.6395 (3)	0.12144 (11)	0.4461 (3)	0.0427 (6)
C4	0.5119 (4)	0.10035 (12)	0.5527 (3)	0.0505 (7)
H4A	0.5516	0.1107	0.6719	0.061*
C5	0.3355 (4)	0.06600 (12)	0.4889 (3)	0.0532 (7)
H5A	0.2576	0.0529	0.5644	0.064*
C6	0.2680 (3)	0.04974 (12)	0.3092 (3)	0.0490 (6)
C7	0.0803 (4)	0.01312 (14)	0.2466 (3)	0.0582 (7)
C8	0.8847 (4)	0.17789 (13)	0.6982 (3)	0.0544 (7)
H8A	0.8699	0.1422	0.7757	0.065*
C9	1.1128 (5)	0.19404 (18)	0.7342 (4)	0.0861 (10)
H9A	1.1873	0.1568	0.7113	0.129*
H9B	1.1666	0.2067	0.8551	0.129*
H9C	1.1300	0.2289	0.6591	0.129*
C10	0.7585 (5)	0.23444 (15)	0.7327 (4)	0.0748 (9)
H10A	0.6149	0.2219	0.7096	0.112*
H10B	0.7704	0.2697	0.6570	0.112*
H10C	0.8098	0.2476	0.8533	0.112*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
C1	0.0550 (14)	0.0553 (15)	0.0343 (11)	0.0006 (12)	0.0111 (10)	0.0007 (10)
O1	0.1008 (16)	0.178 (3)	0.0316 (10)	−0.0490 (16)	0.0207 (10)	−0.0053 (13)
N1	0.0729 (16)	0.0899 (19)	0.0677 (15)	−0.0259 (15)	0.0211 (12)	−0.0044 (14)
O2	0.0723 (13)	0.0866 (14)	0.0533 (10)	−0.0266 (11)	0.0294 (9)	−0.0077 (10)
N2	0.0632 (14)	0.0774 (16)	0.0359 (11)	−0.0117 (12)	0.0185 (9)	0.0019 (10)
C2	0.0502 (13)	0.0511 (14)	0.0323 (11)	−0.0016 (11)	0.0137 (9)	0.0039 (10)
N3	0.0573 (12)	0.0644 (13)	0.0384 (10)	−0.0135 (11)	0.0168 (9)	−0.0083 (9)
C3	0.0488 (13)	0.0452 (13)	0.0349 (11)	0.0013 (11)	0.0128 (10)	0.0009 (10)
C4	0.0603 (15)	0.0625 (16)	0.0313 (11)	−0.0063 (13)	0.0167 (10)	−0.0043 (11)
C5	0.0613 (16)	0.0611 (16)	0.0434 (13)	−0.0030 (13)	0.0245 (11)	0.0034 (11)
C6	0.0484 (14)	0.0523 (15)	0.0464 (13)	−0.0027 (12)	0.0133 (11)	0.0008 (11)
C7	0.0610 (16)	0.0653 (17)	0.0497 (14)	−0.0064 (15)	0.0174 (12)	0.0020 (13)
C8	0.0634 (16)	0.0613 (16)	0.0371 (12)	−0.0052 (13)	0.0112 (11)	−0.0126 (11)
C9	0.073 (2)	0.109 (3)	0.074 (2)	−0.0228 (19)	0.0156 (16)	−0.0385 (19)
C10	0.090 (2)	0.072 (2)	0.0614 (16)	0.0019 (17)	0.0199 (15)	−0.0147 (15)

Geometric parameters (Å, º)

C1—C6	1.374 (3)	C4—H4A	0.9300
C1—C2	1.383 (3)	C5—C6	1.407 (3)
C1—H1A	0.9300	C5—H5A	0.9300
O1—N2	1.221 (2)	C6—C7	1.430 (4)
N1—C7	1.144 (3)	C8—C9	1.506 (4)
O2—N2	1.229 (3)	C8—C10	1.507 (4)
N2—C2	1.445 (3)	C8—H8A	0.9800
C2—C3	1.426 (3)	C9—H9A	0.9600
N3—C3	1.333 (3)	C9—H9B	0.9600
N3—C8	1.473 (3)	C9—H9C	0.9600
N3—H3A	0.8600	C10—H10A	0.9600
C3—C4	1.417 (3)	C10—H10B	0.9600
C4—C5	1.349 (3)	C10—H10C	0.9600
C6—C1—C2	120.3 (2)	C1—C6—C7	122.0 (2)
C6—C1—H1A	119.8	C5—C6—C7	119.0 (2)
C2—C1—H1A	119.8	N1—C7—C6	177.7 (3)
O1—N2—O2	121.3 (2)	N3—C8—C9	107.4 (2)
O1—N2—C2	118.7 (2)	N3—C8—C10	111.8 (2)
O2—N2—C2	120.05 (18)	C9—C8—C10	112.2 (2)
C1—C2—C3	122.2 (2)	N3—C8—H8A	108.4
C1—C2—N2	116.20 (19)	C9—C8—H8A	108.4
C3—C2—N2	121.6 (2)	C10—C8—H8A	108.4
C3—N3—C8	125.47 (19)	C8—C9—H9A	109.5
C3—N3—H3A	117.3	C8—C9—H9B	109.5
C8—N3—H3A	117.3	H9A—C9—H9B	109.5
N3—C3—C4	120.94 (19)	C8—C9—H9C	109.5
N3—C3—C2	124.1 (2)	H9A—C9—H9C	109.5
C4—C3—C2	114.9 (2)	H9B—C9—H9C	109.5
C5—C4—C3	122.9 (2)	C8—C10—H10A	109.5
C5—C4—H4A	118.6	C8—C10—H10B	109.5
C3—C4—H4A	118.6	H10A—C10—H10B	109.5
C4—C5—C6	120.7 (2)	C8—C10—H10C	109.5
C4—C5—H5A	119.7	H10A—C10—H10C	109.5
C6—C5—H5A	119.7	H10B—C10—H10C	109.5
C1—C6—C5	119.0 (2)
C6—C1—C2—C3	−0.2 (4)	N2—C2—C3—C4	179.5 (2)
C6—C1—C2—N2	−179.4 (2)	N3—C3—C4—C5	179.8 (2)
O1—N2—C2—C1	1.9 (4)	C2—C3—C4—C5	0.1 (4)
O2—N2—C2—C1	−177.3 (2)	C3—C4—C5—C6	−0.6 (4)
O1—N2—C2—C3	−177.4 (3)	C2—C1—C6—C5	−0.3 (4)
O2—N2—C2—C3	3.5 (4)	C2—C1—C6—C7	−179.4 (2)
C8—N3—C3—C4	−3.4 (4)	C4—C5—C6—C1	0.6 (4)
C8—N3—C3—C2	176.1 (2)	C4—C5—C6—C7	179.8 (2)
C1—C2—C3—N3	−179.4 (2)	C3—N3—C8—C9	161.5 (3)
N2—C2—C3—N3	−0.1 (4)	C3—N3—C8—C10	−75.0 (3)
C1—C2—C3—C4	0.2 (3)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N3—H3A···O2	0.86	1.99	2.643 (2)	132
C1—H1A···N1^i	0.93	2.61	3.469 (3)	153
C4—H4A···O1^ii	0.93	2.40	3.298 (3)	163
C5—H5A···N1^iii	0.93	2.60	3.529 (4)	175

Symmetry codes: (i) −x, −y, −z; (ii) x, y, z+1; (iii) −x, −y, −z+1.