1H-Indole-3-carbaldehyde

Abstract

In the title compound, C₉H₇NO, the benzene ring forms a dihedral angle of 3.98 (12)° with the pyrrole ring. In the crystal, N–H⋯O hydrogen bonds links the mol­ecules into chains which run parallel to [02-1].

Related literature  

For a related structure, see: Rizal et al. (2008 ▶).

Experimental  

Crystal data  

• C₉H₇NO

• M _r = 145.16

• Orthorhombic,

• a = 14.0758 (9) Å

• b = 5.8059 (4) Å

• c = 8.6909 (5) Å

• V = 710.24 (8) ų

• Z = 4

• Mo Kα radiation

• μ = 0.09 mm⁻¹

• T = 293 K

• 0.30 × 0.20 × 0.20 mm

Data collection  

• Bruker Kappa APEXII CCD diffractometer

• 3791 measured reflections

• 775 independent reflections

• 699 reflections with I > 2σ(I)

• R _int = 0.024

Refinement  

• R[F ² > 2σ(F ²)] = 0.029

• wR(F ²) = 0.069

• S = 1.08

• 775 reflections

• 109 parameters

• 1 restraint

• H atoms treated by a mixture of independent and constrained refinement

• Δρ_max = 0.11 e Å⁻³

• Δρ_min = −0.09 e Å⁻³

Data collection: APEX2 (Bruker, 2004 ▶); cell refinement: APEX2 and SAINT (Bruker, 2004 ▶); data reduction: SAINT and XPREP (Bruker, 2004 ▶); 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: PLATON ▶.

Supplementary Material

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Table 1. Hydrogen-bond geometry (Å, °).

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1A⋯O1i	0.94 (3)	1.92 (3)	2.831 (2)	165 (3)

Symmetry code: (i) .

supplementary crystallographic information

Comment

The molecule is shown with its labelling in Figure 1. The molecules are connected into one-dimensional chains by the N1–H1A···O1(3/2-x,-1+y,1/2+z hydrogen bond which links the molecules into one dimensional chains which run parellel to [2-10], Table 1 and Figure2.

Experimental

Indole was converted to 1H-indole-3-carbaldehyde in the presence of DMF, POCl3, NaOH. 1H-indole-3-carbaldehyde was taken and recrystallized in methanol solvent. The purity of the compound is confirmed by the TLC. A little quantity of compound was taken again for recrystallization to get a pure crystal in methanol solvent medium.

Refinement

H atoms were treated as riding atoms with C—H(aromatic), 0.93 Å with U_iso = 1.2Ueq(C). The H atoms attached to C1 and N1 were located on a difference map and refined isotropically. Friedel pairs were merged.

Figures

Fig. 1.

ORTEP of the title compound with the ellipsoids for non-H atoms are drawn at the 50% probability.

Fig. 2.

Molecular packing view of down the b axis. Dashed lines indicate hydrogen bonds.

Crystal data

C9H7NO	Z = 4
Mr = 145.16	F(000) = 304
Orthorhombic, Pca21	Dx = 1.357 Mg m−3
Hall symbol: P 2c -2ac	Mo Kα radiation, λ = 0.71073 Å
a = 14.0758 (9) Å	µ = 0.09 mm−1
b = 5.8059 (4) Å	T = 293 K
c = 8.6909 (5) Å	Block, colourless
V = 710.24 (8) Å3	0.30 × 0.20 × 0.20 mm

Data collection

Bruker Kappa APEXII CCD diffractometer	699 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.024
Graphite monochromator	θmax = 26.5°, θmin = 2.9°
ω and φ scan	h = −17→16
3791 measured reflections	k = −6→7
775 independent reflections	l = −10→8

Refinement

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)] = 0.029	H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.069	w = 1/[σ2(Fo2) + (0.0297P)2 + 0.0895P] where P = (Fo2 + 2Fc2)/3
S = 1.08	(Δ/σ)max = 0.002
775 reflections	Δρmax = 0.11 e Å−3
109 parameters	Δρmin = −0.09 e Å−3
1 restraint	Extinction correction: SHELXL, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.031 (5)

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	0.76788 (16)	0.4092 (3)	−0.0642 (3)	0.0443 (5)
C2	0.72368 (14)	0.2453 (4)	0.0341 (3)	0.0401 (5)
C3	0.76781 (17)	0.0501 (4)	0.0871 (3)	0.0489 (6)
H3	0.8297	0.0074	0.0628	0.059*
C4	0.62446 (14)	0.0451 (3)	0.1907 (3)	0.0418 (5)
C5	0.54556 (17)	−0.0080 (4)	0.2797 (3)	0.0500 (6)
H5	0.5427	−0.1430	0.3371	0.060*
C6	0.47250 (16)	0.1462 (4)	0.2795 (3)	0.0535 (6)
H6	0.4189	0.1166	0.3388	0.064*
C7	0.47646 (15)	0.3467 (4)	0.1924 (3)	0.0526 (6)
H7	0.4255	0.4487	0.1951	0.063*
C8	0.55405 (16)	0.3976 (4)	0.1024 (3)	0.0449 (5)
H8	0.5555	0.5310	0.0433	0.054*
C9	0.63026 (14)	0.2450 (3)	0.1019 (2)	0.0370 (5)
N1	0.70988 (14)	−0.0700 (3)	0.1783 (2)	0.0510 (5)
O1	0.72964 (12)	0.5795 (2)	−0.1176 (2)	0.0565 (5)
H1	0.8360 (16)	0.376 (4)	−0.086 (3)	0.054 (6)*
H1A	0.7253 (17)	−0.204 (4)	0.233 (4)	0.073 (8)*

Atomic displacement parameters (Ų)

	U11	U22	U33	U12	U13	U23
C1	0.0516 (13)	0.0432 (10)	0.0382 (12)	−0.0002 (9)	0.0027 (11)	−0.0014 (10)
C2	0.0514 (11)	0.0368 (9)	0.0323 (10)	0.0032 (9)	0.0004 (9)	0.0009 (8)
C3	0.0557 (14)	0.0476 (11)	0.0435 (14)	0.0109 (11)	0.0050 (11)	0.0022 (10)
C4	0.0557 (12)	0.0341 (9)	0.0354 (11)	−0.0017 (8)	−0.0038 (10)	0.0013 (10)
C5	0.0666 (14)	0.0435 (12)	0.0399 (13)	−0.0135 (11)	−0.0021 (12)	0.0050 (10)
C6	0.0499 (13)	0.0624 (14)	0.0484 (14)	−0.0136 (11)	0.0036 (11)	−0.0011 (12)
C7	0.0466 (12)	0.0576 (13)	0.0536 (15)	0.0036 (10)	−0.0017 (12)	−0.0041 (14)
C8	0.0512 (12)	0.0406 (10)	0.0428 (13)	0.0013 (9)	−0.0046 (11)	0.0037 (9)
C9	0.0473 (11)	0.0344 (10)	0.0293 (10)	−0.0027 (8)	−0.0052 (9)	−0.0017 (8)
N1	0.0680 (12)	0.0395 (9)	0.0455 (11)	0.0102 (8)	0.0016 (10)	0.0113 (10)
O1	0.0658 (11)	0.0442 (8)	0.0596 (11)	−0.0002 (7)	0.0058 (8)	0.0163 (8)

Geometric parameters (Å, º)

C1—O1	1.218 (2)	C5—C6	1.363 (3)
C1—C2	1.422 (3)	C5—H5	0.9300
C1—H1	1.00 (2)	C6—C7	1.390 (3)
C2—C3	1.372 (3)	C6—H6	0.9300
C2—C9	1.441 (3)	C7—C8	1.375 (3)
C3—N1	1.334 (3)	C7—H7	0.9300
C3—H3	0.9300	C8—C9	1.391 (3)
C4—N1	1.380 (3)	C8—H8	0.9300
C4—C5	1.388 (3)	N1—H1A	0.94 (2)
C4—C9	1.396 (3)
O1—C1—C2	125.4 (2)	C5—C6—C7	121.4 (2)
O1—C1—H1	120.6 (14)	C5—C6—H6	119.3
C2—C1—H1	114.0 (14)	C7—C6—H6	119.3
C3—C2—C1	123.8 (2)	C8—C7—C6	121.4 (2)
C3—C2—C9	105.93 (19)	C8—C7—H7	119.3
C1—C2—C9	130.22 (19)	C6—C7—H7	119.3
N1—C3—C2	110.8 (2)	C7—C8—C9	118.5 (2)
N1—C3—H3	124.6	C7—C8—H8	120.7
C2—C3—H3	124.6	C9—C8—H8	120.7
N1—C4—C5	129.30 (19)	C8—C9—C4	118.84 (19)
N1—C4—C9	107.95 (18)	C8—C9—C2	134.75 (19)
C5—C4—C9	122.65 (19)	C4—C9—C2	106.31 (18)
C6—C5—C4	117.2 (2)	C3—N1—C4	109.04 (17)
C6—C5—H5	121.4	C3—N1—H1A	126.4 (16)
C4—C5—H5	121.4	C4—N1—H1A	124.4 (16)
O1—C1—C2—C3	177.2 (2)	N1—C4—C9—C8	−176.6 (2)
O1—C1—C2—C9	−4.9 (4)	C5—C4—C9—C8	0.1 (3)
C1—C2—C3—N1	179.3 (2)	N1—C4—C9—C2	0.2 (2)
C9—C2—C3—N1	1.0 (3)	C5—C4—C9—C2	176.9 (2)
N1—C4—C5—C6	175.0 (2)	C3—C2—C9—C8	175.3 (2)
C9—C4—C5—C6	−0.9 (3)	C1—C2—C9—C8	−2.8 (4)
C4—C5—C6—C7	0.7 (4)	C3—C2—C9—C4	−0.7 (2)
C5—C6—C7—C8	0.3 (4)	C1—C2—C9—C4	−178.9 (2)
C6—C7—C8—C9	−1.1 (3)	C2—C3—N1—C4	−0.8 (3)
C7—C8—C9—C4	0.9 (3)	C5—C4—N1—C3	−176.0 (2)
C7—C8—C9—C2	−174.8 (2)	C9—C4—N1—C3	0.4 (2)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1A···O1i	0.94 (3)	1.92 (3)	2.831 (2)	165 (3)

Symmetry code: (i) −x+3/2, y−1, z+1/2.