supplementary materials


zq2144 scheme

Acta Cryst. (2012). E68, o233    [ doi:10.1107/S1600536811053906 ]

2-[(Z)-4,7-Dichloro-3,3-dimethyl-2,3-dihydro-1H-indol-2-ylidene]-3-oxopropanenitrile

M. Helliwell, M. M. Baradarani, R. Mohammadnejadaghdam, A. Afghan and J. A. Joule

Abstract top

In the title compound, C13H10Cl2N2O, the ring N atom and its three attached atoms are essentially coplanar with angles adding to 359.8°, indicating conjugation with the 2-formylacrylonitrile subunit. The aldehyde group is oriented to place the carbonyl O atom 2.02 (3) Å from the N-H hydrogen atom. Intramolecular N-H...O and C-H...Cl interactions occur. The geometry of the exocyclic double bond is Z. In the crystal, weak C-H...N hydrogen bonds link the molecules into chains along [1\overline10].

Comment top

We showed that the interaction of 2,3,3-trimethyl-3H-indoles with the Vilsmeier reagent produces (1,3-dihydro-3,3-dimethyl-2H-indol-2-ylidene)propanedials (Baradarani et al., 2006). 2,3,3-Trimethyl-2H-pyrrolo[2,3-f]quinoline, 2,3,3-trimethyl-3H-pyrrolo[3,2-h]quinoline (Rashidi et al., 2009), 2,2',3,3,3',3'-hexamethyl-3H,3'H-5,5'-biindole and 2,3,3,7,8,8-hexamethyl-3H,8H-indolo[7,6-g]indole (Rashidi et al., 2011) behave analogously. The (1,3-dihydroindol-2-ylidene)propanedials were shown to react with arylhydrazines (or hydrazine) to produce 3,3-dimethyl-2-[1-aryl-1H-pyrazol-4-yl]-3H-indoles (Baradarani et al., 2006; Rashidi et al., 2009; Helliwell et al. 2010; Rashidi et al., 2011).

In anticipation that the (1,3-dihydroindol-2-ylidene)propanedials would react with hydroxylamine to produce isoxazol-4-yl-3H-indoles, 2-(4,7-dichloro-1,3-dihydro-3,3-dimethyl-2H-indol-2-ylidene)propanedial was treated with hydroxylamine hydrochloride in refluxing ethanol. The unexpected product of the reaction was 2-(4,7-dichloro-1,3-dihydro-3,3-dimethyl-2H-indol-2-ylidene)-3-oxopropanenitrile as shown by this X-ray diffraction analysis. We interpret this transformation as involving firstly formation of the monooxime 1 which cyclizes to generate hemiacetal 2, fragmentation of which (arrows on 2) would then give the product 3 (Fig. 3).

The sum of the angles of the bonds at the ring nitrogen in the title compound is 359.8 ° showing the extensive conjugation of the nitrogen with the 2-formylacrylonitrile subunit. The geometry of the double bond linking the two heterocyclic subunits is Z. In the crystal structure, there are intramolecular N—H···O and C—H···Cl interactions and weak intermolecular C—H···N hydrogen bonds which link the molecules into chains.

Related literature top

For related structures, see: Baradarani et al. (2006); Helliwell et al. (2010); Rashidi et al. (2009); For related literature, see: Rashidi et al. (2011).

Experimental top

A mixture of 2-(4,7-dichloro-1,3-dihydro-3,3-dimethyl-2H-indol-2-ylidene)propanedial (100 mg, 0.35 mmol) and hydroxylamine hydrochloride (24 mg, 0.35 mmol) in absolute EtOH (10 ml) was heated at reflux for 12 h. The solvent was evaporated and resulting mixture dissolved in water and neutralized with aq. NaOH (2 N). The resulting precipitate was filtered off, washed with water, dried in air and recrystallized from EtOH. Yield 70%, mp 451–456 K, FT—IR (KBr) νmax 3199, 2989, 2941, 2205, 1642, 1539, 1156, 928 cm-1, 1H NMR (CDCl3) δ 1.87 (s, 6H, 2CH3), 7.07 (d, J = 8.7 Hz, 1H, ArH), 7.25 (d, J = 8.7 Hz, 1H, ArH), 9.45 (s, 1H, CHO), 12.32 (bs, 1H, NH), 13C NMR (CDCl3) δ 20.3, 52.9, 81.6, 115.8, 117.8, 125.6, 127.1, 128.7, 129.7, 134.6, 139.4, 177.2, 188.0.

Refinement top

H atoms bonded to C were included in calculated positions using the riding method, with C—H distances of 0.96 Å and Ueq values set at 1.5 times those of the parent atoms for methyl H atoms and C—H distances of 0.93 Å and Ueq values of 1.2 times the parent atom for all other H atoms. The H atom bonded to N1 was found by difference Fourier methods and refined isotropically with the N1—H1N distance refined to 0.88 (3) Å.

Computing details top

Data collection: SMART (Bruker, 2001); cell refinement: SAINT (Bruker, 2002); data reduction: SAINT (Bruker, 2002); 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
[Figure 1] Fig. 1. Plot of the title compound with ellipsoids drawn at the 50% probability level.
[Figure 2] Fig. 2. Packing diagram showing the intramolecular N—H···O hydrogen bonds and the weak intermolecular C—H···N hydrogen bonds, which link the molecules into chains.
[Figure 3] Fig. 3. Reaction scheme.
2-[(Z)-4,7-Dichloro-3,3-dimethyl-2,3-dihydro-1H-indol-2- ylidene]-3-oxopropanenitrile top
Crystal data top
C13H10Cl2N2OZ = 2
Mr = 281.13F(000) = 288
Triclinic, P1Dx = 1.475 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 7.0535 (8) ÅCell parameters from 954 reflections
b = 7.9455 (10) Åθ = 2.7–26.6°
c = 12.2883 (15) ŵ = 0.50 mm1
α = 105.151 (2)°T = 100 K
β = 104.855 (2)°Irregular, colourless
γ = 95.296 (2)°0.60 × 0.60 × 0.40 mm
V = 633.09 (13) Å3
Data collection top
Bruker SMART CCD area-detector
diffractometer
2268 independent reflections
Radiation source: fine-focus sealed tube2028 reflections with I > 2σ(I)
graphiteRint = 0.036
phi and ω scansθmax = 25.4°, θmin = 1.8°
Absorption correction: multi-scan
(SADABS; Bruker, 2001)
h = 78
Tmin = 0.724, Tmax = 1.000k = 97
3237 measured reflectionsl = 1314
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.046Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.127H atoms treated by a mixture of independent and constrained refinement
S = 1.05 w = 1/[σ2(Fo2) + (0.0661P)2 + 0.3121P]
where P = (Fo2 + 2Fc2)/3
2268 reflections(Δ/σ)max < 0.001
169 parametersΔρmax = 0.37 e Å3
0 restraintsΔρmin = 0.33 e Å3
Crystal data top
C13H10Cl2N2Oγ = 95.296 (2)°
Mr = 281.13V = 633.09 (13) Å3
Triclinic, P1Z = 2
a = 7.0535 (8) ÅMo Kα radiation
b = 7.9455 (10) ŵ = 0.50 mm1
c = 12.2883 (15) ÅT = 100 K
α = 105.151 (2)°0.60 × 0.60 × 0.40 mm
β = 104.855 (2)°
Data collection top
Bruker SMART CCD area-detector
diffractometer
2268 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2001)
2028 reflections with I > 2σ(I)
Tmin = 0.724, Tmax = 1.000Rint = 0.036
3237 measured reflectionsθmax = 25.4°
Refinement top
R[F2 > 2σ(F2)] = 0.046H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.127Δρmax = 0.37 e Å3
S = 1.05Δρmin = 0.33 e Å3
2268 reflectionsAbsolute structure: ?
169 parametersFlack parameter: ?
0 restraintsRogers parameter: ?
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
xyzUiso*/Ueq
Cl21.27782 (8)0.70384 (7)0.97251 (5)0.0315 (2)
Cl10.74564 (9)0.06883 (7)0.53899 (5)0.0352 (2)
O10.2509 (2)0.4169 (2)0.53396 (14)0.0312 (4)
N10.6292 (3)0.4367 (2)0.65761 (17)0.0229 (4)
N20.4289 (3)1.0032 (3)0.7934 (2)0.0421 (6)
C10.8201 (3)0.3982 (3)0.69974 (19)0.0226 (5)
C20.8935 (3)0.2435 (3)0.6587 (2)0.0246 (5)
C31.0883 (3)0.2341 (3)0.7155 (2)0.0264 (5)
H31.14160.13330.69000.032*
C41.2042 (3)0.3757 (3)0.8108 (2)0.0265 (5)
H41.33360.36740.84890.032*
C51.1276 (3)0.5315 (3)0.85021 (19)0.0233 (5)
C60.9348 (3)0.5444 (3)0.79314 (19)0.0222 (5)
C70.8125 (3)0.6947 (3)0.80972 (19)0.0225 (5)
C80.6153 (3)0.6045 (3)0.71454 (19)0.0225 (5)
C90.9066 (3)0.8550 (3)0.7818 (2)0.0278 (5)
H9A0.91450.81940.70240.042*
H9B1.03790.89970.83530.042*
H9C0.82610.94590.79020.042*
C100.7818 (4)0.7484 (3)0.9349 (2)0.0298 (5)
H10A0.69600.83550.93900.045*
H10B0.90820.79700.99320.045*
H10C0.72240.64600.94940.045*
C110.4428 (3)0.6762 (3)0.68668 (19)0.0249 (5)
C120.4373 (3)0.8573 (3)0.7470 (2)0.0295 (5)
C130.2650 (3)0.5725 (3)0.5954 (2)0.0280 (5)
H130.15310.62620.58180.034*
H1N0.528 (4)0.371 (4)0.599 (2)0.033 (7)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl20.0233 (3)0.0289 (3)0.0350 (4)0.0044 (2)0.0003 (2)0.0051 (2)
Cl10.0351 (4)0.0219 (3)0.0396 (4)0.0050 (2)0.0025 (3)0.0021 (2)
O10.0254 (9)0.0304 (9)0.0331 (9)0.0027 (7)0.0033 (7)0.0075 (7)
N10.0186 (9)0.0207 (9)0.0273 (10)0.0042 (7)0.0030 (8)0.0070 (7)
N20.0358 (12)0.0330 (12)0.0495 (13)0.0176 (9)0.0022 (10)0.0045 (10)
C10.0215 (11)0.0220 (10)0.0280 (11)0.0062 (8)0.0082 (9)0.0117 (9)
C20.0260 (11)0.0200 (10)0.0283 (11)0.0047 (9)0.0077 (9)0.0082 (9)
C30.0259 (12)0.0230 (11)0.0358 (12)0.0108 (9)0.0113 (10)0.0132 (9)
C40.0213 (11)0.0296 (11)0.0341 (12)0.0092 (9)0.0085 (9)0.0163 (9)
C50.0213 (11)0.0223 (10)0.0258 (11)0.0032 (8)0.0052 (9)0.0081 (9)
C60.0226 (11)0.0204 (10)0.0266 (11)0.0055 (8)0.0086 (9)0.0103 (8)
C70.0211 (11)0.0205 (10)0.0265 (11)0.0068 (8)0.0063 (9)0.0073 (8)
C80.0227 (11)0.0206 (10)0.0259 (11)0.0037 (8)0.0081 (9)0.0091 (8)
C90.0262 (12)0.0201 (10)0.0383 (13)0.0054 (9)0.0084 (10)0.0110 (9)
C100.0266 (12)0.0346 (12)0.0278 (12)0.0098 (10)0.0071 (9)0.0077 (9)
C110.0232 (11)0.0259 (11)0.0295 (12)0.0087 (9)0.0090 (9)0.0119 (9)
C120.0211 (11)0.0326 (13)0.0338 (12)0.0110 (9)0.0035 (9)0.0101 (10)
C130.0224 (11)0.0342 (12)0.0305 (12)0.0078 (9)0.0074 (9)0.0143 (10)
Geometric parameters (Å, °) top
Cl2—C51.760 (2)C6—C71.538 (3)
Cl1—C21.749 (2)C7—C81.536 (3)
O1—C131.249 (3)C7—C91.540 (3)
N1—C81.359 (3)C7—C101.561 (3)
N1—C11.406 (3)C8—C111.393 (3)
N1—H1N0.88 (3)C9—H9A0.9600
N2—C121.165 (3)C9—H9B0.9600
C1—C21.400 (3)C9—H9C0.9600
C1—C61.405 (3)C10—H10A0.9600
C2—C31.392 (3)C10—H10B0.9600
C3—C41.399 (3)C10—H10C0.9600
C3—H30.9300C11—C121.446 (3)
C4—C51.415 (3)C11—C131.454 (3)
C4—H40.9300C13—H130.9300
C5—C61.388 (3)
C8—N1—C1111.42 (18)C6—C7—C10112.45 (17)
C8—N1—H1N119.7 (18)C9—C7—C10111.53 (18)
C1—N1—H1N128.7 (18)N1—C8—C11122.6 (2)
C2—C1—C6123.2 (2)N1—C8—C7110.02 (18)
C2—C1—N1128.0 (2)C11—C8—C7127.41 (19)
C6—C1—N1108.87 (18)C7—C9—H9A109.5
C3—C2—C1117.9 (2)C7—C9—H9B109.5
C3—C2—Cl1121.11 (17)H9A—C9—H9B109.5
C1—C2—Cl1120.99 (17)C7—C9—H9C109.5
C2—C3—C4120.1 (2)H9A—C9—H9C109.5
C2—C3—H3119.9H9B—C9—H9C109.5
C4—C3—H3119.9C7—C10—H10A109.5
C3—C4—C5121.0 (2)C7—C10—H10B109.5
C3—C4—H4119.5H10A—C10—H10B109.5
C5—C4—H4119.5C7—C10—H10C109.5
C6—C5—C4119.5 (2)H10A—C10—H10C109.5
C6—C5—Cl2121.27 (16)H10B—C10—H10C109.5
C4—C5—Cl2119.19 (17)C8—C11—C12120.6 (2)
C5—C6—C1118.17 (19)C8—C11—C13121.2 (2)
C5—C6—C7132.44 (19)C12—C11—C13118.26 (19)
C1—C6—C7109.38 (18)N2—C12—C11178.4 (3)
C8—C7—C6100.22 (16)O1—C13—C11125.0 (2)
C8—C7—C9110.43 (18)O1—C13—H13117.5
C6—C7—C9110.65 (17)C11—C13—H13117.5
C8—C7—C10111.05 (18)
C8—N1—C1—C2176.3 (2)C1—C6—C7—C81.8 (2)
C8—N1—C1—C63.2 (2)C5—C6—C7—C964.1 (3)
C6—C1—C2—C31.4 (3)C1—C6—C7—C9114.8 (2)
N1—C1—C2—C3179.2 (2)C5—C6—C7—C1061.3 (3)
C6—C1—C2—Cl1177.94 (16)C1—C6—C7—C10119.75 (19)
N1—C1—C2—Cl11.5 (3)C1—N1—C8—C11178.22 (19)
C1—C2—C3—C40.4 (3)C1—N1—C8—C72.0 (2)
Cl1—C2—C3—C4179.71 (16)C6—C7—C8—N10.1 (2)
C2—C3—C4—C50.9 (3)C9—C7—C8—N1116.83 (19)
C3—C4—C5—C60.3 (3)C10—C7—C8—N1118.90 (19)
C3—C4—C5—Cl2178.64 (17)C6—C7—C8—C11179.9 (2)
C4—C5—C6—C12.0 (3)C9—C7—C8—C1163.4 (3)
Cl2—C5—C6—C1176.95 (15)C10—C7—C8—C1160.9 (3)
C4—C5—C6—C7176.9 (2)N1—C8—C11—C12177.9 (2)
Cl2—C5—C6—C74.2 (3)C7—C8—C11—C122.3 (3)
C2—C1—C6—C52.6 (3)N1—C8—C11—C131.2 (3)
N1—C1—C6—C5177.89 (18)C7—C8—C11—C13178.6 (2)
C2—C1—C6—C7176.50 (19)C8—C11—C13—O11.5 (3)
N1—C1—C6—C73.0 (2)C12—C11—C13—O1177.7 (2)
C5—C6—C7—C8179.3 (2)
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
C3—H3···N2i0.932.563.256 (3)132.
C10—H10B···Cl20.962.833.473 (2)125.
N1—H1N···O10.88 (3)2.02 (3)2.678 (3)131 (2)
Symmetry codes: (i) x+1, y−1, z.
Table 1
Hydrogen-bond geometry (Å, °)
top
D—H···AD—HH···AD···AD—H···A
C3—H3···N2i0.932.563.256 (3)132.
C10—H10B···Cl20.962.833.473 (2)125.
N1—H1N···O10.88 (3)2.02 (3)2.678 (3)131 (2)
Symmetry codes: (i) x+1, y−1, z.
Acknowledgements top

The authors are grateful to the University of Urmia for financial support of this work.

references
References top

Baradarani, M. M., Afghan, A., Zebarjadi, F., Hasanzadeh, K. & Joule, J. A. (2006). J. Heterocycl. Chem. 43, 1591–1596.

Bruker (2001). SMART and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.

Bruker (2002). SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.

Helliwell, M., Afghan, A., Keshvari, F., Baradarani, M. M. & Joule, J. A. (2010). Acta Cryst. E66, o112.

Rashidi, A., Afghan, A., Baradarani, M. M. & Joule, J. A. (2009). J. Heterocycl. Chem. 46, 428–431.

Rashidi, A., Baradarani, M. M. & Joule, J. A. (2011). ARKIVOC, ii, 252–259.

Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122.