2-[(E)-4-(2-Bromo­phen­yl)but-3-en-2-yl­idene]malononitrile

The title compound, C₁₃H₁₉BrN₂, is planar structure except for the methyl H atoms, the maximum atomic deviation for the non-H atoms being 0.100 (1) Å. The bromo­phenyl and isopropanylidenemalononitrile units are located on opposite sides of the C=C bond, showing an E configuration.

Key indicators

• Single-crystal X-ray study
• T = 291 K
• Mean [sigma](C-C) = 0.004 Å
• R factor = 0.039
• wR factor = 0.112
• Data-to-parameter ratio = 14.1

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT029_ALERT_3_C _diffrn_measured_fraction_theta_full Low .......       0.98
PLAT910_ALERT_3_C Missing # of FCF Reflections Below Th(Min) .....          1
PLAT911_ALERT_3_C Missing # FCF Refl Between THmin & STh/L=  0.597         44
PLAT913_ALERT_3_C Missing # of Very Strong Reflections in FCF ....          4
PLAT790_ALERT_4_C Centre of Gravity not Within Unit Cell: Resd.  #          1
              C13 H9 Br N2

Alert level G
PLAT371_ALERT_2_G Long   C(sp2)-C(sp1) Bond  C11    -   C12    ...       1.44 Ang.
PLAT371_ALERT_2_G Long   C(sp2)-C(sp1) Bond  C11    -   C13    ...       1.44 Ang.
PLAT710_ALERT_4_G Delete 1-2-3 or 2-3-4 Linear Torsion Angle ... #          1
            C9  -C11 -C13 -N1     13.00  0.00   1.555   1.555   1.555   1.555
PLAT710_ALERT_4_G Delete 1-2-3 or 2-3-4 Linear Torsion Angle ... #          2
            C12 -C11 -C13 -N1      5.00  0.00   1.555   1.555   1.555   1.555
PLAT710_ALERT_4_G Delete 1-2-3 or 2-3-4 Linear Torsion Angle ... #         17
            C9  -C11 -C12 -N2     -6.00 10.00   1.555   1.555   1.555   1.555
PLAT710_ALERT_4_G Delete 1-2-3 or 2-3-4 Linear Torsion Angle ... #         18
            C13 -C11 -C12 -N2    175.00 10.00   1.555   1.555   1.555   1.555

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   5 ALERT level C = Check and explain
   6 ALERT level G = General alerts; check

   0 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
   4 ALERT type 3 Indicator that the structure quality may be low
   5 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

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S1. Comment

Malononitrile derivatives have broad application for the preparation of heterocyclic ring compounds. The chemistry of ylidene malononitrile have been studied extensively, From the ring closure reactions, the comounds containing newly formed five or six-membered rings, such as indans (Zhang et al., 2003), naphthalenes (Liu et al., 2002), benzenes (Sepiol et al., 1985) were obtained. Some crystal structures involving ylidene malononitrile groups have been published, including a recent report from our labratory Chen, et al., 2010). As a part of our interest in the synthsis of some complex ring systems, we investigated the title compound (I), which is a diene reagent in Diels-Alder reaction. We report herein the crystal structure of the title compound.

The molecular structure of (I) is shown in Fig. 1. Bond lengths and angles in (I) are normal. The molecule skeleton display an approximately planar structure except for the methyl group.

Related literature

For the use of malononitrile-containing compounds as building blocks in syntheses, see: Liu et al. (2002); Sepiol & Milart (1985); Zhang et al. (2003). For a related structure, see: Chen & Kang (2010).

S2. Experimental

2-(Propan-2-ylidene)malononitrile (0.212 g, 2 mmol) and 2-bromobenzaldehyde (0.366 g, 2 mmol) were dissolved in 2-propanol (2 ml). To the solution was added piperidine (0.017 g, 0.2 mmol), the solution was stirred for 24 h at 343 K. Then the reaction was cooled to room temperature, and the solution was filtered to obtain a yellow solid. Recrystallization from hot ethanol afforded the pure compound. Single crystals of (I) suitable for X-ray analysis were obtained by slow evaporation ethyl acetate solution.

S3. Refinement

H atoms were placed in calculated positions with C—H = 0.93–0.96 Å, and refined using a riding model with U_iso(H) = 1.5U_eq(C) for methyl H atoms and U_iso(H) = 1.2U_eq(C) for the others.

Computing details

Data collection: CrysAlis CCD (Oxford Diffraction, 2008); cell refinement: CrysAlis RED (Oxford Diffraction, 2008); data reduction: CrysAlis RED(Oxford Diffraction, 2008); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures

Fig. 1. The molecular structure of (I) with 30% probability displacement ellipsoids (arbitrary spheres for H atoms).

2-[(E)-4-(2-Bromophenyl)but-3-en-2-ylidene]propanedinitrile

Crystal data

C13H9BrN2	Z = 2
Mr = 273.13	F(000) = 272
Triclinic, P1	Dx = 1.540 Mg m^−3
Hall symbol: -P 1	Cu Kα radiation, λ = 1.54184 Å
a = 7.0353 (7) Å	Cell parameters from 3664 reflections
b = 7.0765 (5) Å	θ = 6.8–71.9°
c = 13.3229 (8) Å	µ = 4.52 mm^−1
α = 82.192 (6)°	T = 291 K
β = 76.628 (8)°	Block, yellow
γ = 66.038 (9)°	0.36 × 0.32 × 0.24 mm
V = 589.03 (8) Å^3

Data collection

Oxford Diffraction Xcalibur Sapphire3 Gemini ultra diffractometer	2062 independent reflections
Radiation source: Enhance Ultra (Cu) X-ray Source	1923 reflections with I > 2σ(I)
Mirror monochromator	Rint = 0.024
Detector resolution: 7.9575 pixels mm^-1	θmax = 67.0°, θmin = 6.8°
ω scans	h = −8→6
Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction, 2009)	k = −8→8
Tmin = 0.293, Tmax = 0.410	l = −15→15
4500 measured reflections

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.039	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.112	H-atom parameters constrained
S = 1.06	w = 1/[σ^2(Fo^2) + (0.0759P)^2 + 0.0933P] where P = (Fo^2 + 2Fc^2)/3
2062 reflections	(Δ/σ)max < 0.001
146 parameters	Δρmax = 0.59 e Å^−3
0 restraints	Δρmin = −0.55 e Å^−3

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
Br1	0.67339 (5)	0.15902 (4)	0.54256 (2)	0.06643 (19)
C8	0.8775 (4)	−0.3609 (4)	0.7789 (2)	0.0493 (6)
H8	0.8557	−0.3515	0.8499	0.059*
N2	1.2571 (5)	−1.0939 (4)	0.7188 (2)	0.0735 (8)
C11	1.0519 (4)	−0.7373 (4)	0.7984 (2)	0.0455 (5)
C4	0.5298 (5)	0.2647 (5)	0.8955 (2)	0.0598 (7)
H4	0.4994	0.2887	0.9655	0.072*
C13	1.0087 (4)	−0.7342 (4)	0.9092 (2)	0.0527 (6)
C5	0.6402 (5)	0.0655 (4)	0.8620 (2)	0.0563 (6)
H5	0.6835	−0.0433	0.9103	0.068*
C9	0.9905 (4)	−0.5636 (4)	0.7362 (2)	0.0461 (5)
C7	0.8037 (4)	−0.1879 (4)	0.7217 (2)	0.0516 (6)
H7	0.8277	−0.2024	0.6510	0.062*
C2	0.5107 (4)	0.3937 (4)	0.7208 (3)	0.0563 (7)
H2	0.4684	0.5041	0.6732	0.068*
C10	1.0389 (5)	−0.5797 (5)	0.6211 (2)	0.0584 (7)
H10A	1.1160	−0.7222	0.6044	0.088*
H10B	1.1228	−0.5013	0.5895	0.088*
H10C	0.9087	−0.5260	0.5958	0.088*
C6	0.6889 (4)	0.0226 (4)	0.7573 (2)	0.0478 (6)
N1	0.9737 (5)	−0.7329 (5)	0.9974 (2)	0.0749 (8)
C3	0.4644 (4)	0.4289 (4)	0.8242 (3)	0.0604 (7)
H3	0.3891	0.5629	0.8466	0.072*
C12	1.1667 (4)	−0.9376 (4)	0.7555 (2)	0.0532 (6)
C1	0.6206 (4)	0.1936 (4)	0.6873 (2)	0.0496 (6)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Br1	0.0880 (3)	0.0444 (2)	0.0549 (3)	−0.01383 (17)	−0.01666 (17)	0.00310 (15)
C8	0.0616 (14)	0.0331 (13)	0.0509 (14)	−0.0141 (11)	−0.0134 (11)	−0.0042 (10)
N2	0.0868 (17)	0.0364 (14)	0.0813 (19)	−0.0086 (12)	−0.0094 (14)	−0.0120 (13)
C11	0.0542 (12)	0.0334 (12)	0.0467 (13)	−0.0140 (10)	−0.0109 (10)	−0.0024 (10)
C4	0.0712 (16)	0.0478 (15)	0.0555 (16)	−0.0208 (13)	−0.0032 (13)	−0.0105 (12)
C13	0.0673 (15)	0.0354 (13)	0.0519 (17)	−0.0138 (11)	−0.0196 (12)	0.0028 (11)
C5	0.0706 (16)	0.0384 (14)	0.0559 (16)	−0.0179 (12)	−0.0128 (12)	0.0009 (12)
C9	0.0549 (12)	0.0336 (12)	0.0481 (14)	−0.0145 (10)	−0.0117 (10)	−0.0024 (10)
C7	0.0654 (14)	0.0336 (13)	0.0522 (15)	−0.0145 (11)	−0.0141 (11)	−0.0015 (11)
C2	0.0583 (14)	0.0329 (13)	0.0699 (19)	−0.0105 (11)	−0.0140 (13)	0.0022 (12)
C10	0.0780 (17)	0.0425 (15)	0.0469 (15)	−0.0169 (13)	−0.0093 (13)	−0.0031 (11)
C6	0.0539 (13)	0.0318 (12)	0.0551 (15)	−0.0140 (10)	−0.0119 (11)	0.0003 (10)
N1	0.105 (2)	0.0617 (17)	0.0521 (17)	−0.0232 (15)	−0.0236 (14)	0.0012 (12)
C3	0.0602 (15)	0.0371 (14)	0.076 (2)	−0.0120 (11)	−0.0060 (13)	−0.0109 (13)
C12	0.0629 (15)	0.0354 (14)	0.0566 (16)	−0.0150 (12)	−0.0122 (12)	0.0011 (12)
C1	0.0508 (12)	0.0359 (13)	0.0575 (15)	−0.0125 (10)	−0.0116 (11)	0.0009 (11)

Geometric parameters (Å, º)

Br1—C1	1.908 (3)	C5—H5	0.9300
C8—C7	1.327 (4)	C9—C10	1.502 (4)
C8—C9	1.449 (4)	C7—C6	1.461 (4)
C8—H8	0.9300	C7—H7	0.9300
N2—C12	1.140 (4)	C2—C3	1.373 (5)
C11—C9	1.358 (4)	C2—C1	1.387 (4)
C11—C12	1.437 (4)	C2—H2	0.9300
C11—C13	1.438 (4)	C10—H10A	0.9600
C4—C5	1.383 (4)	C10—H10B	0.9600
C4—C3	1.390 (5)	C10—H10C	0.9600
C4—H4	0.9300	C6—C1	1.412 (4)
C13—N1	1.144 (4)	C3—H3	0.9300
C5—C6	1.401 (4)
C7—C8—C9	123.3 (3)	C3—C2—C1	120.0 (3)
C7—C8—H8	118.4	C3—C2—H2	120.0
C9—C8—H8	118.4	C1—C2—H2	120.0
C9—C11—C12	120.8 (2)	C9—C10—H10A	109.5
C9—C11—C13	123.1 (2)	C9—C10—H10B	109.5
C12—C11—C13	116.1 (2)	H10A—C10—H10B	109.5
C5—C4—C3	119.7 (3)	C9—C10—H10C	109.5
C5—C4—H4	120.2	H10A—C10—H10C	109.5
C3—C4—H4	120.2	H10B—C10—H10C	109.5
N1—C13—C11	179.5 (3)	C5—C6—C1	116.6 (2)
C4—C5—C6	121.9 (3)	C5—C6—C7	122.1 (2)
C4—C5—H5	119.0	C1—C6—C7	121.3 (3)
C6—C5—H5	119.0	C2—C3—C4	120.2 (3)
C11—C9—C8	121.1 (2)	C2—C3—H3	119.9
C11—C9—C10	120.0 (2)	C4—C3—H3	119.9
C8—C9—C10	119.0 (2)	N2—C12—C11	178.1 (3)
C8—C7—C6	127.4 (3)	C2—C1—C6	121.5 (3)
C8—C7—H7	116.3	C2—C1—Br1	117.1 (2)
C6—C7—H7	116.3	C6—C1—Br1	121.4 (2)
C9—C11—C13—N1	131 (44)	C8—C7—C6—C5	−0.8 (5)
C12—C11—C13—N1	−49 (45)	C8—C7—C6—C1	179.5 (3)
C3—C4—C5—C6	−0.1 (5)	C1—C2—C3—C4	0.9 (4)
C12—C11—C9—C8	−179.0 (2)	C5—C4—C3—C2	−0.5 (5)
C13—C11—C9—C8	0.7 (4)	C9—C11—C12—N2	−6 (10)
C12—C11—C9—C10	1.1 (4)	C13—C11—C12—N2	175 (10)
C13—C11—C9—C10	−179.1 (3)	C3—C2—C1—C6	−0.6 (4)
C7—C8—C9—C11	−176.0 (3)	C3—C2—C1—Br1	178.9 (2)
C7—C8—C9—C10	3.8 (4)	C5—C6—C1—C2	0.0 (4)
C9—C8—C7—C6	−179.9 (3)	C7—C6—C1—C2	179.7 (3)
C4—C5—C6—C1	0.4 (4)	C5—C6—C1—Br1	−179.5 (2)
C4—C5—C6—C7	−179.4 (3)	C7—C6—C1—Br1	0.2 (3)