2-[(E)-(Dimethyl­amino)methyl­ene­amino]benzonitrile

Wei, X.; Shi, D.; Fan, Y.; Zhang, L.; Li, J.

doi:10.1107/S1600536809015979

organic compounds

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ISSN: 2056-9890

Volume 65| Part 6| June 2009| Page o1306

doi:10.1107/S1600536809015979

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2-[(E)-(Dimethylamino)methyleneamino]benzonitrile

Xia Wei,^a Daxin Shi,^a Yanqiu Fan,^a Ling Zhang ^a and Jiarong Li ^a ^*

^aSchool of Chemical Engineering and Environment, Beijing Institute of Technology, Beijing 100081, People's Republic of China
^*Correspondence e-mail: jrli@bit.edu.cn

(Received 1 April 2009; accepted 28 April 2009; online 14 May 2009)

In the title compound, C₁₀H₁₁N₃, the amidine unit, including the two methyl substituents, is virtually planar [maximum deviation = 0.016 (5) Å]. The plane of the benzene ring forms a dihedral angle of 46.5 (3)° with the amidine group.

Related literature

For application of formamidines in chemical synthesis, see: Deshpande & Seshadri (1973 ); Toste et al. (1994 ).

Experimental

Crystal data

C₁₀H₁₁N₃
M_r = 173.22
Monoclinic, P 2₁ /n
a = 7.7468 (15) Å
b = 11.212 (2) Å
c = 11.042 (2) Å
β = 109.67 (3)°
V = 903.1 (3) Å³
Z = 4
Mo Kα radiation
μ = 0.08 mm⁻¹
T = 113 K
0.20 × 0.18 × 0.14 mm

Data collection

Rigaku Saturn diffractometer
Absorption correction: multi-scan (CrystalClear; Rigaku/MSC, 2005 ) T_min = 0.984, T_max = 0.989
5746 measured reflections
1575 independent reflections
1342 reflections with I > 2σ(I)
R_int = 0.027

Refinement

R[F² > 2σ(F²)] = 0.035
wR(F²) = 0.100
S = 1.10
1575 reflections
120 parameters
H-atom parameters constrained
Δρ_max = 0.19 e Å⁻³
Δρ_min = −0.17 e Å⁻³

Data collection: CrystalClear (Rigaku/MSC, 2005); cell refinement: CrystalClear; data reduction: CrystalClear; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809015979/gk2203sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809015979/gk2203Isup2.hkl

checkCIF report

Comment top

Derivatives of formamidine are valuable synthetic intermediates featuring common structural motif found in a variety of compounds with interesting medicinal and biological properties. The formamidine group is a useful primary amine protecting group for its ease of introduction and efficient removal (Toste et al., 1994). The N'-(2-cyanophenyl)-N,N-dimethylformamidine compounds are key intermediates of convenient synthesis of O-aminobenzonitrile, 4-aminoquinazolines and 4-aminoquinazoline-3-oxides (Deshpande et al., 1973).

Related literature top

For application of formamidines in chemical synthesis, see: Deshpande & Seshadri (1973); Toste et al. (1994).

Experimental top

Phosphorus oxychloride (13 mmole) was added dropwise to 8 ml dimethylformamide at 273 K. After stirring for 2–3 min, finely powdered isatin-3-oxime (10 mmol) was added and kept at room temperature for some time. Temperature was then gradually raised to 343 K and the reaction mixture was kept at this temperature for 2hr, then cooled, poured onto crushed ice and filtered. The clear filtrate was basified by sodium carbonate to pH=9 and the solution extracted with toluene, which was then evaporated to obtain crude (E)-N'-(2-cyanophenyl)-N,N-dimethylformamidine. The compound was recrystallizated from ethyl acetate and petroleum ether to give colorless crystals.

m.p. 338–339 K; IR(KBr): 2910 (C—H), 2214.87 (–CN), 1587, 1556 (C—C), 1367 (–CH3) cm^-1; 1H-NMR (CDCl3, p.p.m): 3.07–3.09 (6H, m), 6.93–7.02(2H, m), 7.38–7.44 (1H, t), 7.51–7.54 (1H, d), 7.58 (1H, s); ESI: 174.1[M+H]⁺. Elementary analysis: found N 24.31, C 69.31, H 6.30; calc. 24.26, 69.34, 6.40).

20 mg of the obtained product was dissolved in ethyl acetate (5 ml). Then petroleum ether (2 ml) was added dropwise to the solution. The solution was kept at room temperature for 4 days to give colorless single crystals.

Computing details top

Data collection: CrystalClear (Rigaku/MSC, 2005); cell refinement: CrystalClear (Rigaku/MSC, 2005); data reduction: CrystalClear (Rigaku/MSC, 2005); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top

Fig. 1. Molecular structure of the title compound with displacement ellipsoids drawn at the 30% probability level.

2-[(E)-(Dimethylamino)methyleneamino]benzonitrile top

Crystal data top

C₁₀H₁₁N₃	F(000) = 368
M_r = 173.22	D_x = 1.274 Mg m⁻³
Monoclinic, P2₁/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -p 2yn	Cell parameters from 2901 reflections
a = 7.7468 (15) Å	θ = 1.8–27.9°
b = 11.212 (2) Å	µ = 0.08 mm⁻¹
c = 11.042 (2) Å	T = 113 K
β = 109.67 (3)°	Cube, colorless
V = 903.1 (3) Å³	0.20 × 0.18 × 0.14 mm
Z = 4

Data collection top

Rigaku Saturn diffractometer	1575 independent reflections
Radiation source: rotating anode	1342 reflections with I > 2σ(I)
Confocal monochromator	R_int = 0.027
ω scans	θ_max = 25.0°, θ_min = 2.7°
Absorption correction: multi-scan (CrystalClear; Rigaku/MSC, 2005)	h = −9→8
T_min = 0.984, T_max = 0.989	k = −13→13
5746 measured reflections	l = −13→13

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)] = 0.035	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.100	H-atom parameters constrained
S = 1.10	w = 1/[σ²(F_o²) + (0.0612P)² + 0.137P] where P = (F_o² + 2F_c²)/3
1575 reflections	(Δ/σ)_max = 0.001
120 parameters	Δρ_max = 0.19 e Å⁻³
0 restraints	Δρ_min = −0.17 e Å⁻³

Crystal data top

C₁₀H₁₁N₃	V = 903.1 (3) Å³
M_r = 173.22	Z = 4
Monoclinic, P2₁/n	Mo Kα radiation
a = 7.7468 (15) Å	µ = 0.08 mm⁻¹
b = 11.212 (2) Å	T = 113 K
c = 11.042 (2) Å	0.20 × 0.18 × 0.14 mm
β = 109.67 (3)°

Data collection top

Rigaku Saturn diffractometer	1575 independent reflections
Absorption correction: multi-scan (CrystalClear; Rigaku/MSC, 2005)	1342 reflections with I > 2σ(I)
T_min = 0.984, T_max = 0.989	R_int = 0.027
5746 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.035	0 restraints
wR(F²) = 0.100	H-atom parameters constrained
S = 1.10	Δρ_max = 0.19 e Å⁻³
1575 reflections	Δρ_min = −0.17 e Å⁻³
120 parameters

Special details top

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 (Å²) top

	x	y	z	U_iso*/U_eq
N1	−0.14481 (15)	0.99786 (9)	0.10732 (10)	0.0224 (3)
N2	0.07129 (13)	0.79099 (9)	0.36257 (9)	0.0164 (3)
N3	0.06421 (14)	0.76114 (9)	0.56842 (9)	0.0188 (3)
C1	−0.06597 (16)	0.90883 (10)	0.12357 (11)	0.0161 (3)
C2	0.02451 (15)	0.79498 (10)	0.13459 (11)	0.0149 (3)
C3	0.04571 (16)	0.74551 (11)	0.02435 (11)	0.0175 (3)
H3	0.0069	0.7875	−0.0527	0.021*
C4	0.12454 (16)	0.63393 (11)	0.02985 (12)	0.0189 (3)
H4	0.1380	0.6005	−0.0435	0.023*
C5	0.18342 (16)	0.57226 (11)	0.14586 (11)	0.0177 (3)
H5	0.2354	0.4970	0.1496	0.021*
C6	0.16547 (15)	0.62165 (10)	0.25572 (11)	0.0163 (3)
H6	0.2079	0.5795	0.3326	0.020*
C7	0.08444 (16)	0.73434 (11)	0.25378 (11)	0.0145 (3)
C8	0.04348 (16)	0.72373 (11)	0.45021 (11)	0.0170 (3)
H8	0.0071	0.6452	0.4290	0.020*
C9	0.02345 (19)	0.68383 (12)	0.66108 (13)	0.0272 (3)
H9A	−0.0296	0.6108	0.6197	0.041*
H9B	−0.0615	0.7231	0.6941	0.041*
H9C	0.1345	0.6666	0.7305	0.041*
C10	0.13692 (18)	0.87915 (11)	0.61196 (12)	0.0231 (3)
H10A	0.2098	0.9060	0.5621	0.035*
H10B	0.2115	0.8756	0.7011	0.035*
H10C	0.0374	0.9337	0.6014	0.035*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
N1	0.0285 (6)	0.0188 (6)	0.0200 (6)	0.0012 (5)	0.0085 (5)	0.0002 (4)
N2	0.0166 (5)	0.0180 (5)	0.0143 (5)	0.0000 (4)	0.0048 (4)	0.0003 (4)
N3	0.0216 (6)	0.0221 (6)	0.0146 (6)	0.0030 (4)	0.0086 (4)	0.0022 (4)
C1	0.0171 (6)	0.0187 (6)	0.0116 (6)	−0.0043 (5)	0.0038 (5)	−0.0009 (5)
C2	0.0126 (6)	0.0145 (6)	0.0169 (6)	−0.0025 (5)	0.0038 (5)	−0.0002 (4)
C3	0.0174 (6)	0.0197 (6)	0.0138 (6)	−0.0019 (5)	0.0033 (5)	0.0018 (5)
C4	0.0195 (6)	0.0207 (6)	0.0163 (6)	−0.0019 (5)	0.0057 (5)	−0.0045 (5)
C5	0.0156 (6)	0.0154 (6)	0.0210 (6)	−0.0001 (5)	0.0044 (5)	−0.0014 (5)
C6	0.0146 (6)	0.0171 (6)	0.0154 (6)	−0.0023 (5)	0.0025 (5)	0.0027 (5)
C7	0.0110 (6)	0.0171 (6)	0.0145 (6)	−0.0049 (4)	0.0029 (5)	−0.0011 (4)
C8	0.0145 (6)	0.0180 (6)	0.0184 (7)	0.0018 (5)	0.0053 (5)	0.0008 (5)
C9	0.0312 (7)	0.0328 (8)	0.0228 (7)	0.0074 (6)	0.0159 (6)	0.0092 (6)
C10	0.0243 (7)	0.0269 (7)	0.0182 (7)	0.0031 (6)	0.0071 (5)	−0.0046 (5)

Geometric parameters (Å, º) top

N1—C1	1.1522 (15)	C4—H4	0.9300
N2—C8	1.3007 (15)	C5—C6	1.3825 (16)
N2—C7	1.3925 (15)	C5—H5	0.9300
N3—C8	1.3283 (15)	C6—C7	1.4077 (17)
N3—C9	1.4544 (15)	C6—H6	0.9300
N3—C10	1.4549 (16)	C8—H8	0.9300
C1—C2	1.4415 (16)	C9—H9A	0.9600
C2—C3	1.3967 (16)	C9—H9B	0.9600
C2—C7	1.4137 (17)	C9—H9C	0.9600
C3—C4	1.3844 (17)	C10—H10A	0.9600
C3—H3	0.9300	C10—H10B	0.9600
C4—C5	1.3906 (17)	C10—H10C	0.9600

C8—N2—C7	117.12 (10)	C7—C6—H6	119.3
C8—N3—C9	121.34 (11)	N2—C7—C6	123.91 (11)
C8—N3—C10	121.14 (10)	N2—C7—C2	119.17 (11)
C9—N3—C10	117.46 (10)	C6—C7—C2	116.79 (10)
N1—C1—C2	175.84 (12)	N2—C8—N3	123.54 (11)
C3—C2—C7	121.49 (11)	N2—C8—H8	118.2
C3—C2—C1	118.33 (10)	N3—C8—H8	118.2
C7—C2—C1	120.15 (10)	N3—C9—H9A	109.5
C4—C3—C2	120.01 (11)	N3—C9—H9B	109.5
C4—C3—H3	120.0	H9A—C9—H9B	109.5
C2—C3—H3	120.0	N3—C9—H9C	109.5
C3—C4—C5	119.52 (11)	H9A—C9—H9C	109.5
C3—C4—H4	120.2	H9B—C9—H9C	109.5
C5—C4—H4	120.2	N3—C10—H10A	109.5
C6—C5—C4	120.70 (11)	N3—C10—H10B	109.5
C6—C5—H5	119.7	H10A—C10—H10B	109.5
C4—C5—H5	119.7	N3—C10—H10C	109.5
C5—C6—C7	121.48 (11)	H10A—C10—H10C	109.5
C5—C6—H6	119.3	H10B—C10—H10C	109.5

C7—C2—C3—C4	0.94 (17)	C5—C6—C7—C2	−0.75 (16)
C1—C2—C3—C4	−177.12 (10)	C3—C2—C7—N2	175.72 (9)
C2—C3—C4—C5	−0.49 (17)	C1—C2—C7—N2	−6.25 (16)
C3—C4—C5—C6	−0.57 (17)	C3—C2—C7—C6	−0.32 (16)
C4—C5—C6—C7	1.21 (17)	C1—C2—C7—C6	177.71 (10)
C8—N2—C7—C6	−35.50 (15)	C7—N2—C8—N3	166.09 (11)
C8—N2—C7—C2	148.77 (11)	C9—N3—C8—N2	177.22 (10)
C5—C6—C7—N2	−176.58 (10)	C10—N3—C8—N2	−5.75 (18)

Experimental details

Crystal data
Chemical formula	C₁₀H₁₁N₃
M_r	173.22
Crystal system, space group	Monoclinic, P2₁/n
Temperature (K)	113
a, b, c (Å)	7.7468 (15), 11.212 (2), 11.042 (2)
β (°)	109.67 (3)
V (Å³)	903.1 (3)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.08
Crystal size (mm)	0.20 × 0.18 × 0.14

Data collection
Diffractometer	Rigaku Saturn diffractometer
Absorption correction	Multi-scan (CrystalClear; Rigaku/MSC, 2005)
T_min, T_max	0.984, 0.989
No. of measured, independent and observed [I > 2σ(I)] reflections	5746, 1575, 1342
R_int	0.027
(sin θ/λ)_max (Å⁻¹)	0.595

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.035, 0.100, 1.10
No. of reflections	1575
No. of parameters	120
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.19, −0.17

Computer programs: CrystalClear (Rigaku/MSC, 2005), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Acknowledgements

The authors thank the Beijing Institute of Technology for financial support.

References

Deshpande, M. N. & Seshadri, S. (1973). Indian J. Chem. 11, 538–540. CAS Google Scholar
Rigaku/MSC (2005). CrystalClear. Rigaku/MSC Inc., The Woodlands, Texas, USA. Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Toste, D., McNulty, J. & Still, W. J. (1994). Synth. Commun. 24, 1617–1624. CrossRef CAS Web of Science Google Scholar