(3E)-3-[(4-Butyl­phenyl)­imino]-1,3-di­hydro-2H-indol-2-one

The title compound, C₁₈H₁₈N₂O, has a non-planar conform­ation. The indol and butyl­phenyl groups are connected by a C—N bond [1.433 (3) Å]. The crystal structure is stabilized by intermolecular N—H...N and C—H...O interactions.

Key indicators

• Single-crystal X-ray study
• T = 294 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.049
• wR factor = 0.128
• Data-to-parameter ratio = 15.4

checkCIF results

No syntax errors found

ADDSYM reports no extra symmetry


 Alert Level C:



PLAT_369  Alert C Long   C(sp2)-C(sp2) Bond  C(1)   -   C(2)   =       1.53 Ang.


 0 Alert Level A = Potentially serious problem

 0 Alert Level B = Potential problem

 1 Alert Level C = Please check

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S1. Comment

Isatin (see Scheme) and its derivatives have been used as reagents in the dye industry. Schiff bases of isatin were reported to possess anti-HIV (Pandeya et al., 2000), antifungal (Pandeya et al., 1999), antibacterial (Sarangapani & Reddy, 1994; Varma & Nobles, 1975), antiviral (Singh et al., 1983), antiprotozoal (Varma & Khan, 1977) and antihelminthic (Sarciron et al., 1993) activities. The medical and biological implications of this category of ligands has already been proved (Popp & Pajouhesh, 1982).

The structure of the title compound, (I), is shown in Fig. 1. The C1—C2 bond length [1.529 (3) Å] is within the range 1.49–1.56 Å observed for related compounds found in the Cambridge Structural Database (Allen, 2002). The C2—N2—C9 angle is 119.6 (2)°. In the butyl group, the average C—C—C bond angle is 114.7 (3)° and this group shows an E form. The indol group is planar [maximum displacement is 0.004 (2) Å for C1] and forms a dihedral angle of 89.8 (1)° with the phenyl plane. These bond distances and angles agree with the values reported for (3E)-3-[(4-hexylphenyl)imino]-1H-indol-2(3H)-one (Öztürk et al., 2003).

The N—H···N and C—H···O hydrogen bonds build zigzag chains roughly parallel to the b axis (Fig. 2). The geometry of the hydrogen bonds is given in table 2.

To determine the structural and electronic parameters of (I), quantum-chemical calculations were carried out using the PM3 method. It was found that the charges at atoms O1, N1 and N2 are 0.0382, 0.0609 and −0.2930 e⁻, respectively. The final heat of formation of (I) is 14.98 kcal and its total energy is −3027.82 eV. The energies of the HOMO and LUMO levels have the values of −9.0903 and −0.9315 eV, respectively. The molecule dipole moment calculated is 4.352 Debye.

S2. Experimental

The title compound was prepared according to the method of Öztürk et al.,(2003). The orange product was recrystallized from methanol (m.p. 451–458 K).

S3. Refinement

The H atoms of C—H and N—H groups were placed in calculated positions (C—H = 0.96 Å and N—H = 0.86 Å) and were allowed to refine as riding models, with displacement parameters fixed at 120% or 150% (CH₃) of those of their parent atoms.

Computing details

Data collection: COLLECT (Nonius, 1999); cell refinement: EVALCCD (Duisenberg, 1998); data reduction: EVALCCD (Duisenberg, 1998); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997; Burnett & Johnson, 1996); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures

	Fig. 1. The molecular structure of (I), showing 50% probability displacement ellipsoids and the atom-numbering scheme.
	Fig. 2. A view of the intermolecular hydrogen-bond contacts, showing the zigzag chain which develops parallel to b. [Symmetry codes: (i) −x, −y, − z; (ii) x, −y + 1/2, z + 1/2.[

(3E)-3-[(4-butylphenyl)imino]-1,3-dihydro-2H-indol-2-one

Crystal data

C18H18N2O	F(000) = 592
Mr = 278.34	Dx = 1.232 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 171 reflections
a = 15.6069 (2) Å	θ = 6.0–26.0°
b = 9.5596 (2) Å	µ = 0.08 mm^−1
c = 10.5265 (2) Å	T = 294 K
β = 107.187 (2)°	Slab, orange
V = 1500.38 (5) Å^3	0.40 × 0.31 × 0.17 mm
Z = 4

Data collection

Nonius KappaCCD diffractometer	1851 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.072
Graphite monochromator	θmax = 26.0°, θmin = 3.5°
Detector resolution: 9 pixels mm^-1	h = −19→19
ω scans with 2.0° and 40 s per frame	k = −11→11
9152 measured reflections	l = −12→12
2938 independent 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)] = 0.049	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.128	H-atom parameters constrained
S = 1.02	w = 1/[σ^2(Fo^2) + (0.0558P)^2 + 0.2681P] where P = (Fo^2 + 2Fc^2)/3
2938 reflections	(Δ/σ)max < 0.001
191 parameters	Δρmax = 0.17 e Å^−3
0 restraints	Δρmin = −0.21 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 on F² for all reflections except those flagged by the user for potential systematic errors. Weighted R-factors wR and all goodnesses of fit S are based on F², conventional R-factors R are based on F, with F set to zero for negative F². The observed criterion of F² > σ(F²) is used only for calculating -R-factor-obs 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
O1	−0.00800 (10)	0.45419 (17)	0.66538 (14)	0.0548 (5)
N1	0.02190 (11)	0.60983 (18)	0.84099 (16)	0.0413 (4)
H1	−0.0157	0.6748	0.8057	0.050*
N2	0.12672 (11)	0.28683 (18)	0.84436 (16)	0.0411 (4)
C1	0.03073 (12)	0.4889 (2)	0.77876 (19)	0.0373 (5)
C2	0.10399 (12)	0.4053 (2)	0.87887 (18)	0.0334 (5)
C3	0.13338 (12)	0.4930 (2)	0.99803 (18)	0.0327 (4)
C4	0.08206 (12)	0.6161 (2)	0.97086 (18)	0.0353 (5)
C5	0.09191 (14)	0.7213 (2)	1.0630 (2)	0.0450 (5)
H5	0.0581	0.8029	1.0437	0.054*
C6	0.15471 (15)	0.7003 (2)	1.1865 (2)	0.0476 (6)
H6	0.1629	0.7699	1.2508	0.057*
C7	0.20529 (14)	0.5793 (2)	1.2167 (2)	0.0444 (5)
H7	0.2464	0.5684	1.3005	0.053*
C8	0.19490 (13)	0.4743 (2)	1.12285 (18)	0.0392 (5)
H8	0.2285	0.3926	1.1429	0.047*
C9	0.20169 (13)	0.2142 (2)	0.93106 (18)	0.0363 (5)
C10	0.28569 (14)	0.2393 (2)	0.9179 (2)	0.0458 (5)
H10	0.2927	0.3037	0.8556	0.055*
C11	0.35967 (14)	0.1687 (2)	0.9974 (2)	0.0485 (6)
H11	0.4160	0.1864	0.9876	0.058*
C12	0.35132 (14)	0.0719 (2)	1.0914 (2)	0.0415 (5)
C13	0.26638 (14)	0.0460 (2)	1.0999 (2)	0.0453 (5)
H13	0.2591	−0.0201	1.1606	0.054*
C14	0.19136 (14)	0.1152 (2)	1.02083 (19)	0.0439 (5)
H14	0.1347	0.0951	1.0283	0.053*
C15	0.43427 (15)	0.0033 (3)	1.1822 (2)	0.0550 (6)
H15A	0.4701	−0.0340	1.1288	0.066*
H15B	0.4163	−0.0744	1.2278	0.066*
C16	0.49166 (15)	0.1037 (3)	1.2851 (2)	0.0574 (6)
H16A	0.5099	0.1806	1.2388	0.069*
H16B	0.4550	0.1424	1.3366	0.069*
C17	0.57407 (16)	0.0397 (3)	1.3791 (3)	0.0694 (8)
H17A	0.6111	0.0020	1.3278	0.083*
H17B	0.5559	−0.0378	1.4248	0.083*
C18	0.62972 (17)	0.1392 (3)	1.4812 (3)	0.0786 (9)
H18A	0.6554	0.2089	1.4378	0.118*
H18B	0.6768	0.0885	1.5437	0.118*
H18C	0.5925	0.1838	1.5273	0.118*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0502 (9)	0.0601 (11)	0.0408 (8)	0.0009 (8)	−0.0071 (7)	0.0029 (8)
N1	0.0355 (9)	0.0393 (11)	0.0446 (10)	0.0067 (8)	0.0050 (7)	0.0118 (8)
N2	0.0383 (10)	0.0375 (10)	0.0398 (9)	0.0005 (8)	−0.0003 (7)	0.0003 (8)
C1	0.0317 (10)	0.0377 (12)	0.0397 (11)	−0.0042 (9)	0.0060 (9)	0.0075 (9)
C2	0.0279 (9)	0.0350 (12)	0.0356 (10)	−0.0038 (8)	0.0065 (8)	0.0041 (9)
C3	0.0302 (10)	0.0322 (11)	0.0358 (10)	−0.0026 (8)	0.0100 (8)	0.0032 (8)
C4	0.0316 (10)	0.0365 (12)	0.0391 (10)	−0.0003 (9)	0.0124 (8)	0.0063 (9)
C5	0.0487 (13)	0.0363 (12)	0.0526 (13)	0.0062 (10)	0.0191 (10)	0.0020 (10)
C6	0.0545 (13)	0.0460 (14)	0.0436 (12)	−0.0024 (11)	0.0166 (10)	−0.0077 (10)
C7	0.0441 (12)	0.0510 (14)	0.0350 (11)	−0.0028 (10)	0.0067 (9)	−0.0015 (10)
C8	0.0381 (11)	0.0394 (12)	0.0365 (11)	0.0014 (9)	0.0052 (9)	0.0024 (9)
C9	0.0382 (11)	0.0298 (11)	0.0355 (10)	0.0004 (9)	0.0026 (8)	−0.0065 (9)
C10	0.0476 (13)	0.0397 (13)	0.0477 (12)	−0.0024 (10)	0.0102 (10)	0.0078 (10)
C11	0.0366 (12)	0.0496 (14)	0.0582 (13)	0.0009 (10)	0.0121 (10)	0.0058 (11)
C12	0.0419 (12)	0.0311 (12)	0.0470 (12)	0.0025 (9)	0.0059 (9)	−0.0033 (9)
C13	0.0491 (13)	0.0394 (13)	0.0435 (12)	−0.0044 (10)	0.0075 (10)	0.0073 (10)
C14	0.0366 (11)	0.0485 (14)	0.0437 (11)	−0.0016 (10)	0.0073 (9)	0.0033 (10)
C15	0.0495 (13)	0.0455 (14)	0.0633 (15)	0.0109 (11)	0.0065 (11)	0.0051 (12)
C16	0.0507 (13)	0.0512 (15)	0.0612 (15)	0.0116 (11)	0.0026 (11)	0.0033 (12)
C17	0.0455 (14)	0.081 (2)	0.0734 (17)	0.0128 (13)	0.0041 (13)	0.0128 (15)
C18	0.0573 (16)	0.099 (2)	0.0672 (17)	0.0066 (16)	−0.0010 (13)	0.0034 (16)

Geometric parameters (Å, º)

O1—C1	1.214 (2)	C10—H10	0.9300
N1—C1	1.356 (3)	C11—C12	1.389 (3)
N1—C4	1.413 (2)	C11—H11	0.9300
N1—H1	0.8600	C12—C13	1.377 (3)
N2—C2	1.272 (2)	C12—C15	1.512 (3)
N2—C9	1.433 (2)	C13—C14	1.387 (3)
C1—C2	1.531 (3)	C13—H13	0.9300
C2—C3	1.465 (3)	C14—H14	0.9300
C3—C8	1.391 (2)	C15—C16	1.524 (3)
C3—C4	1.404 (3)	C15—H15A	0.9700
C4—C5	1.374 (3)	C15—H15B	0.9700
C5—C6	1.392 (3)	C16—C17	1.502 (3)
C5—H5	0.9300	C16—H16A	0.9700
C6—C7	1.384 (3)	C16—H16B	0.9700
C6—H6	0.9300	C17—C18	1.504 (4)
C7—C8	1.384 (3)	C17—H17A	0.9700
C7—H7	0.9300	C17—H17B	0.9700
C8—H8	0.9300	C18—H18A	0.9600
C9—C10	1.379 (3)	C18—H18B	0.9600
C9—C14	1.380 (3)	C18—H18C	0.9600
C10—C11	1.385 (3)
C1—N1—C4	111.73 (16)	C10—C11—H11	119.4
C1—N1—H1	124.1	C12—C11—H11	119.4
C4—N1—H1	124.1	C13—C12—C11	117.42 (19)
C2—N2—C9	119.60 (16)	C13—C12—C15	122.8 (2)
O1—C1—N1	128.03 (18)	C11—C12—C15	119.7 (2)
O1—C1—C2	125.99 (19)	C12—C13—C14	122.3 (2)
N1—C1—C2	105.91 (16)	C12—C13—H13	118.9
N2—C2—C3	135.31 (17)	C14—C13—H13	118.9
N2—C2—C1	118.87 (17)	C9—C14—C13	119.3 (2)
C3—C2—C1	105.79 (16)	C9—C14—H14	120.4
C8—C3—C4	119.52 (18)	C13—C14—H14	120.4
C8—C3—C2	133.61 (18)	C12—C15—C16	112.92 (18)
C4—C3—C2	106.82 (15)	C12—C15—H15A	109.0
C5—C4—C3	122.11 (17)	C16—C15—H15A	109.0
C5—C4—N1	128.15 (18)	C12—C15—H15B	109.0
C3—C4—N1	109.73 (17)	C16—C15—H15B	109.0
C4—C5—C6	117.1 (2)	H15A—C15—H15B	107.8
C4—C5—H5	121.5	C17—C16—C15	114.9 (2)
C6—C5—H5	121.5	C17—C16—H16A	108.5
C7—C6—C5	122.1 (2)	C15—C16—H16A	108.5
C7—C6—H6	119.0	C17—C16—H16B	108.5
C5—C6—H6	119.0	C15—C16—H16B	108.5
C6—C7—C8	120.24 (19)	H16A—C16—H16B	107.5
C6—C7—H7	119.9	C16—C17—C18	114.5 (2)
C8—C7—H7	119.9	C16—C17—H17A	108.6
C7—C8—C3	118.96 (19)	C18—C17—H17A	108.6
C7—C8—H8	120.5	C16—C17—H17B	108.6
C3—C8—H8	120.5	C18—C17—H17B	108.6
C10—C9—C14	119.63 (18)	H17A—C17—H17B	107.6
C10—C9—N2	118.27 (18)	C17—C18—H18A	109.5
C14—C9—N2	121.99 (19)	C17—C18—H18B	109.5
C9—C10—C11	120.2 (2)	H18A—C18—H18B	109.5
C9—C10—H10	119.9	C17—C18—H18C	109.5
C11—C10—H10	119.9	H18A—C18—H18C	109.5
C10—C11—C12	121.2 (2)	H18B—C18—H18C	109.5
C4—N1—C1—O1	−176.6 (2)	C5—C6—C7—C8	0.4 (3)
C4—N1—C1—C2	0.7 (2)	C6—C7—C8—C3	0.3 (3)
C9—N2—C2—C3	−4.6 (3)	C4—C3—C8—C7	−1.3 (3)
C9—N2—C2—C1	173.16 (17)	C2—C3—C8—C7	−178.2 (2)
O1—C1—C2—N2	−1.6 (3)	C2—N2—C9—C10	−89.5 (2)
N1—C1—C2—N2	−178.90 (18)	C2—N2—C9—C14	94.3 (2)
O1—C1—C2—C3	176.76 (19)	C14—C9—C10—C11	−2.0 (3)
N1—C1—C2—C3	−0.5 (2)	N2—C9—C10—C11	−178.34 (19)
N2—C2—C3—C8	−4.6 (4)	C9—C10—C11—C12	0.0 (3)
C1—C2—C3—C8	177.5 (2)	C10—C11—C12—C13	1.8 (3)
N2—C2—C3—C4	178.2 (2)	C10—C11—C12—C15	−176.3 (2)
C1—C2—C3—C4	0.2 (2)	C11—C12—C13—C14	−1.6 (3)
C8—C3—C4—C5	1.5 (3)	C15—C12—C13—C14	176.5 (2)
C2—C3—C4—C5	179.24 (18)	C10—C9—C14—C13	2.3 (3)
C8—C3—C4—N1	−177.56 (17)	N2—C9—C14—C13	178.45 (19)
C2—C3—C4—N1	0.2 (2)	C12—C13—C14—C9	−0.5 (3)
C1—N1—C4—C5	−179.6 (2)	C13—C12—C15—C16	−107.3 (3)
C1—N1—C4—C3	−0.5 (2)	C11—C12—C15—C16	70.6 (3)
C3—C4—C5—C6	−0.8 (3)	C12—C15—C16—C17	179.0 (2)
N1—C4—C5—C6	178.12 (19)	C15—C16—C17—C18	−179.4 (2)
C4—C5—C6—C7	−0.2 (3)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···N2^i	0.86	2.24	3.062 (2)	159
C5—H5···O1^i	0.93	2.56	3.254 (3)	132

Symmetry code: (i) −x, y+1/2, −z+3/2.