(Z)-2-Amino-3-[(E)-benzyl­ideneamino]but-2-enedinitrile

Varsha, G.; Arun, V.; Sebastian, M.; Leeju, P.; Varghese, D.; Yusuff, K.K.M.

doi:10.1107/S1600536809010873

organic compounds

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Volume 65| Part 4| April 2009| Page o919

doi:10.1107/S1600536809010873

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(Z)-2-Amino-3-[(E)-benzylideneamino]but-2-enedinitrile

G. Varsha,^a V. Arun,^a Manju Sebastian,^a P. Leeju,^a Digna Varghese ^a and K. K. M. Yusuff ^a ^*

^aDepartment of Applied Chemistry, Cochin University of Science and Technology, Kochi 682 022, Kerala, India
^*Correspondence e-mail: yusuff@cusat.ac.in

(Received 17 March 2009; accepted 24 March 2009; online 28 March 2009)

The asymmetric unit of the title compound, C₁₁H₈N₄, contains two independent molecules. In the crystal structure, intermolecular N—H⋯N hydrogen bonds link molecules into ribbons extended in the [100] direction.

Related literature

For some properties of Schiff base ligands, see: Arun, Robinson et al. (2009 ); Arun, Sridevi et al. (2009 ). For related structures, see: MacLachlan et al. (1996 ); Mague & Eduok (2000 ); Varghese et al. (2009 ).

Experimental

Crystal data

C₁₁H₈N₄
M_r = 196.21
Monoclinic, P 2₁ /c
a = 6.9569 (19) Å
b = 22.796 (6) Å
c = 13.516 (4) Å
β = 100.983 (5)°
V = 2104.2 (10) Å³
Z = 8
Mo Kα radiation radiation
μ = 0.08 mm⁻¹
T = 298 K
0.42 × 0.18 × 0.18 mm

Data collection

Bruker SMART APEX CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 2001 ) T_min = 0.980, T_max = 0.984
12239 measured reflections
4173 independent reflections
3216 reflections with I > 2σ(I)
R_int = 0.036

Refinement

R[F² > 2σ(F²)] = 0.106
wR(F²) = 0.214
S = 1.29
4173 reflections
272 parameters
H-atom parameters constrained
Δρ_max = 0.22 e Å⁻³
Δρ_min = −0.21 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N2—H2A⋯N3ⁱ	0.86	2.36	3.096 (4)	144
N2—H2B⋯N8ⁱⁱ	0.86	2.25	3.090 (5)	165
N6—H6A⋯N7ⁱⁱⁱ	0.86	2.51	3.228 (5)	142
N6—H6B⋯N4^iv	0.86	2.28	3.057 (4)	150
Symmetry codes: (i) x-1, y, z; (ii) $[-x, y+{\script{1\over 2}}, -z+{\script{1\over 2}}]$ ; (iii) x+1, y, z; (iv) $[-x+1, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]$ .

Data collection: SMART (Bruker, 2000 ); cell refinement: SAINT (Bruker, 2000); 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, 2009 ).

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536809010873/cv2533sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809010873/cv2533Isup2.hkl

checkCIF report

Comment top

In continuation of our study of Schiff base ligands and their metal complexes (Arun, Robinson et al., 2009; Arun, Sridevi et al., 2009; Varghese et al., 2009), we present here the title compound, (I).

The asymmetric unit of (I) contains two independent molecules (Fig. 1). All bond lengths and angles in (I) are normal and correspond to those observed in the related compounds (MacLachlan et al., 1996; Mague & Eduok 2000). In both independent molecules, the benzene ring and diaminomaleonitrile moiety are anti with respect to azomethine C=N. In the crystal structure, intermolecular N—H···N hydrogen bonds (Table 1) link the molecules into ribbons extended in direction [100].

Related literature top

For some properties of Schiff base ligands, see: Arun, Robinson et al. (2009); Arun, Sridevi et al. (2009). For related structures, see: MacLachlan et al. (1996); Mague & Eduok (2000); Varghese et al. (2009).

Experimental top

Benzaldehyde (Merck) and 2,3-diaminomaleonitrile (Aldrich) are of reagent grade and are used without further purification. A hot solution of 2,3-diaminomaleonitrile (1 mmol) in methanol (25 ml) was added slowly over a hot solution of benzaldehyde (1 mmol) in the same solvent (25 ml) and the solution was refluxed for three hours. The resulting yellow solution was cooled in ice and the precipitated imine was filtered off and washed with cold methanol and dried under vacuum. Yellow crystals of (1) suitable for X-ray analysis were obtained by slow evaporation of the Schiff base in absolute ethanol (yield 85%; m.p. 463 K).

Computing details top

Data collection: SMART (Bruker, 2000); cell refinement: SAINT (Bruker, 2000); data reduction: SAINT (Bruker, 2000); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures top

Fig. 1. Two independent molecules of (I) with the atomic labelling scheme and 50% probability displacement ellipsoids.

(Z)-2-Amino-3-[(E)-benzylideneamino]but-2-enedinitrile top

Crystal data top

C₁₁H₈N₄	F(000) = 816
M_r = 196.21	D_x = 1.239 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 4803 reflections
a = 6.9569 (19) Å	θ = 2.4–26.1°
b = 22.796 (6) Å	µ = 0.08 mm⁻¹
c = 13.516 (4) Å	T = 298 K
β = 100.983 (5)°	Rod, yellow
V = 2104.2 (10) Å³	0.42 × 0.18 × 0.18 mm
Z = 8

Data collection top

Bruker SMART APEX CCD area-detector diffractometer	4173 independent reflections
Radiation source: fine-focus sealed tube	3216 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.036
ϕ and ω scans	θ_max = 26.1°, θ_min = 1.8°
Absorption correction: multi-scan (SADABS; Sheldrick, 2001)	h = −8→8
T_min = 0.980, T_max = 0.984	k = −28→23
12239 measured reflections	l = −16→15

Refinement top

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)] = 0.106	H-atom parameters constrained
wR(F²) = 0.214	w = 1/[σ²(F_o²) + (0.0476P)² + 1.6604P] where P = (F_o² + 2F_c²)/3
S = 1.29	(Δ/σ)_max < 0.001
4173 reflections	Δρ_max = 0.22 e Å⁻³
272 parameters	Δρ_min = −0.21 e Å⁻³
0 restraints	Extinction correction: SHELXTL (Sheldrick, 2008), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0021 (6)

Crystal data top

C₁₁H₈N₄	V = 2104.2 (10) Å³
M_r = 196.21	Z = 8
Monoclinic, P2₁/c	Mo Kα radiation
a = 6.9569 (19) Å	µ = 0.08 mm⁻¹
b = 22.796 (6) Å	T = 298 K
c = 13.516 (4) Å	0.42 × 0.18 × 0.18 mm
β = 100.983 (5)°

Data collection top

Bruker SMART APEX CCD area-detector diffractometer	4173 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 2001)	3216 reflections with I > 2σ(I)
T_min = 0.980, T_max = 0.984	R_int = 0.036
12239 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.106	0 restraints
wR(F²) = 0.214	H-atom parameters constrained
S = 1.29	Δρ_max = 0.22 e Å⁻³
4173 reflections	Δρ_min = −0.21 e Å⁻³
272 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
C1	0.3264 (5)	0.39467 (14)	0.3626 (2)	0.0398 (8)
C2	0.3971 (6)	0.34110 (16)	0.3379 (3)	0.0590 (11)
H2	0.5196	0.3387	0.3202	0.071*
C3	0.2851 (8)	0.29092 (19)	0.3397 (4)	0.0772 (14)
H3	0.3324	0.2548	0.3229	0.093*
C4	0.1054 (8)	0.2944 (2)	0.3661 (4)	0.0792 (15)
H4	0.0313	0.2606	0.3677	0.095*
C5	0.0339 (6)	0.3473 (2)	0.3902 (3)	0.0673 (12)
H5	−0.0887	0.3494	0.4078	0.081*
C6	0.1427 (5)	0.39773 (17)	0.3883 (3)	0.0501 (9)
H6	0.0933	0.4337	0.4043	0.060*
C7	0.4454 (5)	0.44731 (14)	0.3591 (3)	0.0388 (8)
H7	0.5684	0.4436	0.3422	0.047*
C8	0.5013 (4)	0.54703 (14)	0.3760 (2)	0.0366 (8)
C9	0.4227 (5)	0.60037 (14)	0.3899 (3)	0.0397 (8)
C10	0.6996 (5)	0.54341 (15)	0.3605 (3)	0.0469 (9)
C11	0.5356 (5)	0.65316 (15)	0.3859 (3)	0.0459 (9)
N1	0.3855 (4)	0.49769 (11)	0.3784 (2)	0.0367 (7)
N2	0.2412 (4)	0.60811 (13)	0.4084 (2)	0.0558 (9)
H2A	0.1673	0.5783	0.4122	0.067*
H2B	0.1991	0.6429	0.4165	0.067*
N3	0.8559 (5)	0.53781 (16)	0.3485 (3)	0.0764 (12)
N4	0.6208 (5)	0.69534 (14)	0.3808 (3)	0.0693 (11)
C12	0.2008 (5)	0.53605 (15)	0.1295 (3)	0.0452 (9)
C13	0.3849 (5)	0.53053 (17)	0.1052 (3)	0.0550 (10)
H13	0.4312	0.4934	0.0933	0.066*
C14	0.4994 (7)	0.5783 (2)	0.0985 (4)	0.0736 (13)
H14	0.6224	0.5739	0.0819	0.088*
C15	0.4310 (8)	0.6331 (2)	0.1165 (4)	0.0823 (16)
H15	0.5078	0.6659	0.1109	0.099*
C16	0.2515 (9)	0.64021 (18)	0.1425 (4)	0.0821 (16)
H16	0.2090	0.6775	0.1562	0.098*
C17	0.1334 (7)	0.59197 (17)	0.1484 (3)	0.0639 (12)
H17	0.0104	0.5967	0.1648	0.077*
C18	0.0775 (5)	0.48496 (15)	0.1349 (3)	0.0450 (9)
H18	−0.0432	0.4899	0.1538	0.054*
C19	0.0133 (4)	0.38528 (14)	0.1179 (3)	0.0379 (8)
C20	0.0863 (5)	0.33203 (15)	0.0987 (3)	0.0416 (8)
C21	−0.1801 (5)	0.38947 (15)	0.1396 (3)	0.0450 (9)
C22	−0.0336 (6)	0.28020 (17)	0.0983 (3)	0.0540 (10)
N5	0.1316 (4)	0.43361 (12)	0.1143 (2)	0.0396 (7)
N6	0.2648 (4)	0.32364 (12)	0.0767 (2)	0.0555 (9)
H6A	0.3410	0.3531	0.0741	0.067*
H6B	0.3028	0.2888	0.0652	0.067*
N7	−0.3334 (4)	0.39419 (15)	0.1568 (3)	0.0660 (10)
N8	−0.1258 (5)	0.23914 (15)	0.0977 (3)	0.0809 (13)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0501 (19)	0.0328 (18)	0.0338 (19)	−0.0032 (15)	0.0015 (15)	0.0035 (15)
C2	0.070 (3)	0.036 (2)	0.069 (3)	0.0021 (19)	0.007 (2)	0.002 (2)
C3	0.112 (4)	0.035 (2)	0.079 (3)	−0.002 (3)	0.006 (3)	0.005 (2)
C4	0.110 (4)	0.053 (3)	0.070 (3)	−0.038 (3)	0.006 (3)	0.010 (2)
C5	0.067 (3)	0.069 (3)	0.064 (3)	−0.026 (2)	0.009 (2)	0.003 (2)
C6	0.056 (2)	0.042 (2)	0.052 (2)	−0.0072 (17)	0.0069 (18)	0.0007 (18)
C7	0.0369 (17)	0.0353 (19)	0.045 (2)	0.0016 (14)	0.0104 (15)	−0.0001 (15)
C8	0.0334 (16)	0.0365 (19)	0.0387 (19)	−0.0038 (14)	0.0042 (14)	−0.0004 (15)
C9	0.0413 (18)	0.0328 (18)	0.044 (2)	−0.0093 (15)	0.0064 (15)	0.0002 (16)
C10	0.044 (2)	0.039 (2)	0.059 (2)	−0.0075 (16)	0.0116 (17)	−0.0016 (17)
C11	0.051 (2)	0.034 (2)	0.050 (2)	−0.0021 (17)	0.0028 (17)	0.0064 (17)
N1	0.0324 (13)	0.0315 (15)	0.0451 (17)	−0.0031 (12)	0.0045 (12)	0.0013 (13)
N2	0.0506 (17)	0.0364 (17)	0.085 (3)	−0.0009 (14)	0.0238 (17)	−0.0085 (16)
N3	0.0413 (18)	0.066 (2)	0.127 (4)	−0.0080 (17)	0.030 (2)	−0.011 (2)
N4	0.078 (2)	0.038 (2)	0.089 (3)	−0.0181 (18)	0.010 (2)	0.0034 (18)
C12	0.057 (2)	0.0302 (19)	0.042 (2)	−0.0028 (16)	−0.0046 (17)	0.0012 (16)
C13	0.060 (2)	0.048 (2)	0.057 (3)	−0.0086 (19)	0.010 (2)	0.0004 (19)
C14	0.085 (3)	0.058 (3)	0.077 (3)	−0.026 (2)	0.013 (3)	−0.002 (2)
C15	0.109 (4)	0.060 (3)	0.070 (3)	−0.038 (3)	−0.005 (3)	0.007 (3)
C16	0.125 (4)	0.022 (2)	0.084 (4)	−0.002 (3)	−0.018 (3)	0.002 (2)
C17	0.078 (3)	0.040 (2)	0.067 (3)	0.009 (2)	−0.006 (2)	−0.006 (2)
C18	0.0454 (19)	0.044 (2)	0.045 (2)	0.0033 (16)	0.0091 (16)	−0.0035 (17)
C19	0.0361 (16)	0.0337 (19)	0.043 (2)	−0.0032 (14)	0.0058 (15)	0.0029 (15)
C20	0.0466 (19)	0.0349 (19)	0.043 (2)	−0.0065 (15)	0.0083 (16)	−0.0014 (16)
C21	0.0450 (19)	0.038 (2)	0.051 (2)	−0.0029 (16)	0.0064 (17)	−0.0022 (17)
C22	0.054 (2)	0.041 (2)	0.070 (3)	−0.0045 (18)	0.017 (2)	−0.006 (2)
N5	0.0410 (15)	0.0309 (15)	0.0456 (17)	−0.0022 (12)	0.0050 (13)	−0.0021 (13)
N6	0.0520 (18)	0.0287 (16)	0.093 (3)	0.0009 (14)	0.0315 (18)	−0.0022 (16)
N7	0.0443 (18)	0.070 (2)	0.088 (3)	−0.0002 (17)	0.0241 (18)	0.002 (2)
N8	0.072 (2)	0.046 (2)	0.127 (4)	−0.0218 (19)	0.026 (2)	−0.005 (2)

Geometric parameters (Å, º) top

C1—C2	1.381 (5)	C12—C13	1.387 (5)
C1—C6	1.389 (5)	C12—C17	1.398 (5)
C1—C7	1.464 (4)	C12—C18	1.457 (5)
C2—C3	1.387 (6)	C13—C14	1.362 (5)
C2—H2	0.9300	C13—H13	0.9300
C3—C4	1.365 (7)	C14—C15	1.375 (6)
C3—H3	0.9300	C14—H14	0.9300
C4—C5	1.369 (6)	C15—C16	1.370 (7)
C4—H4	0.9300	C15—H15	0.9300
C5—C6	1.378 (5)	C16—C17	1.384 (6)
C5—H5	0.9300	C16—H16	0.9300
C6—H6	0.9300	C17—H17	0.9300
C7—N1	1.266 (4)	C18—N5	1.276 (4)
C7—H7	0.9300	C18—H18	0.9300
C8—C9	1.360 (4)	C19—C20	1.360 (4)
C8—N1	1.387 (4)	C19—N5	1.382 (4)
C8—C10	1.437 (4)	C19—C21	1.434 (4)
C9—N2	1.345 (4)	C20—N6	1.344 (4)
C9—C11	1.443 (4)	C20—C22	1.446 (5)
C10—N3	1.136 (4)	C21—N7	1.139 (4)
C11—N4	1.138 (4)	C22—N8	1.134 (4)
N2—H2A	0.8600	N6—H6A	0.8600
N2—H2B	0.8600	N6—H6B	0.8600

C2—C1—C6	119.5 (3)	C13—C12—C17	118.9 (4)
C2—C1—C7	119.2 (3)	C13—C12—C18	121.2 (3)
C6—C1—C7	121.3 (3)	C17—C12—C18	119.9 (4)
C1—C2—C3	119.9 (4)	C14—C13—C12	121.4 (4)
C1—C2—H2	120.1	C14—C13—H13	119.3
C3—C2—H2	120.1	C12—C13—H13	119.3
C4—C3—C2	120.1 (4)	C13—C14—C15	119.2 (5)
C4—C3—H3	119.9	C13—C14—H14	120.4
C2—C3—H3	119.9	C15—C14—H14	120.4
C3—C4—C5	120.3 (4)	C16—C15—C14	121.1 (4)
C3—C4—H4	119.8	C16—C15—H15	119.5
C5—C4—H4	119.8	C14—C15—H15	119.5
C4—C5—C6	120.3 (4)	C15—C16—C17	120.1 (4)
C4—C5—H5	119.8	C15—C16—H16	120.0
C6—C5—H5	119.8	C17—C16—H16	120.0
C5—C6—C1	119.8 (4)	C16—C17—C12	119.4 (4)
C5—C6—H6	120.1	C16—C17—H17	120.3
C1—C6—H6	120.1	C12—C17—H17	120.3
N1—C7—C1	121.8 (3)	N5—C18—C12	121.4 (3)
N1—C7—H7	119.1	N5—C18—H18	119.3
C1—C7—H7	119.1	C12—C18—H18	119.3
C9—C8—N1	118.1 (3)	C20—C19—N5	117.3 (3)
C9—C8—C10	119.6 (3)	C20—C19—C21	119.9 (3)
N1—C8—C10	122.3 (3)	N5—C19—C21	122.9 (3)
N2—C9—C8	124.0 (3)	N6—C20—C19	124.3 (3)
N2—C9—C11	115.7 (3)	N6—C20—C22	116.1 (3)
C8—C9—C11	120.3 (3)	C19—C20—C22	119.6 (3)
N3—C10—C8	176.8 (4)	N7—C21—C19	178.4 (4)
N4—C11—C9	178.2 (4)	N8—C22—C20	179.1 (4)
C7—N1—C8	121.0 (3)	C18—N5—C19	121.4 (3)
C9—N2—H2A	120.0	C20—N6—H6A	120.0
C9—N2—H2B	120.0	C20—N6—H6B	120.0
H2A—N2—H2B	120.0	H6A—N6—H6B	120.0

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N2—H2A···N3ⁱ	0.86	2.36	3.096 (4)	144
N2—H2B···N8ⁱⁱ	0.86	2.25	3.090 (5)	165
N6—H6A···N7ⁱⁱⁱ	0.86	2.51	3.228 (5)	142
N6—H6B···N4^iv	0.86	2.28	3.057 (4)	150

Symmetry codes: (i) x−1, y, z; (ii) −x, y+1/2, −z+1/2; (iii) x+1, y, z; (iv) −x+1, y−1/2, −z+1/2.

Experimental details

Crystal data
Chemical formula	C₁₁H₈N₄
M_r	196.21
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	298
a, b, c (Å)	6.9569 (19), 22.796 (6), 13.516 (4)
β (°)	100.983 (5)
V (Å³)	2104.2 (10)
Z	8
Radiation type	Mo Kα
µ (mm⁻¹)	0.08
Crystal size (mm)	0.42 × 0.18 × 0.18

Data collection
Diffractometer	Bruker SMART APEX CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 2001)
T_min, T_max	0.980, 0.984
No. of measured, independent and observed [I > 2σ(I)] reflections	12239, 4173, 3216
R_int	0.036
(sin θ/λ)_max (Å⁻¹)	0.619

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.106, 0.214, 1.29
No. of reflections	4173
No. of parameters	272
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.22, −0.21

Computer programs: SMART (Bruker, 2000), SAINT (Bruker, 2000), SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N2—H2A···N3ⁱ	0.86	2.36	3.096 (4)	143.6
N2—H2B···N8ⁱⁱ	0.86	2.25	3.090 (5)	164.7
N6—H6A···N7ⁱⁱⁱ	0.86	2.51	3.228 (5)	141.7
N6—H6B···N4^iv	0.86	2.28	3.057 (4)	149.9

Symmetry codes: (i) x−1, y, z; (ii) −x, y+1/2, −z+1/2; (iii) x+1, y, z; (iv) −x+1, y−1/2, −z+1/2.

Acknowledgements

The X-ray data were collected on the diffractometer facilities at the University of Hyderabad provided by the Department of Science and Technology. MS thanks KSCSTE, Trivandrum, Kerala, for financial assistance. DV gratefully acknowledges financial support from the Council of Scientific and Industrial Research (CSIR), India.

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