1-Benzyl-3-[(4-meth­oxy­phen­yl)imino]­indolin-2-one

Odedokun, O.A.; Ikotun, A.A.; Ajaelu, C.J.; Bhuvanesh, N.

doi:10.1107/S2414314623004182

organic compounds

IUCrDATA

ISSN: 2414-3146

Volume 8| Part 5| May 2023| x230418

https://doi.org/10.1107/S2414314623004182

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1-Benzyl-3-[(4-methoxyphenyl)imino]indolin-2-one

Omobola A. Odedokun,^a,^b Adebomi A. Ikotun,^a,^c ^* Chijioke J. Ajaelu ^a and Nattamai Bhuvanesh ^c

^aIndustrial Chemistry, Bowen University, Iwo, Osun State, Nigeria, ^bDepartment of Chemistry, Federal College of Education (Special), Oyo, Oyo State, Nigeria, and ^cDepartment of Chemistry, Texas A & M University, College Station, Texas, USA
^*Correspondence e-mail: adebomi.ikotun@bowen.edu.ng

Edited by S. Bernès, Benemérita Universidad Autónoma de Puebla, México (Received 13 April 2023; accepted 13 May 2023; online 19 May 2023)

The title compound, C₂₂H₁₈N₂O₂, is a Schiff base obtained by condensing p-arnisidine (4-methoxyaniline) with N-benzylisatin (1-benzyl-1H-indole-2,3-dione), which crystallizes in the triclinic P $[\overline{1}]$ space group. The benzyl and phenyl rings subtend dihedral angles of 76.08 (7) and 60.70 (6)°, respectively, with the isatin group. The imino C=N double bond exists in an E conformation.

Keywords: crystal structure; N-benzylisatin; p-arnisidine; Schiff base.

CCDC reference: 2262787

Structure description

Isatin (1H, indole-2,3-dione), an indole, and its analogs are an important class of heterocyclic compounds due to the presence of the indole ring structure, which is common to many pharmaceutical agents (Visagaperumal et al., 2018 ). Isatin and its derivatives have served as starting materials for several organic, metal–organic and organometallic syntheses (Garima & Sumitra 2014 ; Ikotun et al., 2015 , 2019 ). These compounds attract great interest because of their potent pharmacological and biological activities (Guo, 2019 ; Czeleń et al., 2022 ; Ikotun et al., 2022 ). N-Benzylisatin is a biologically potent derivative of isatin that has been used to prepare many new biologically potent Schiff bases and complexes suitable for medicinal purposes (Shakir & Al-Mudhafar, 2020 ; Banerjee, 2021 ). The crystal structure of N-benzylisatin has been determined (Akkurt et al., 2006 ; Schutte et al., 2012 ). We have previously reported the synthesis and crystal structure of the Schiff base prepared from N-benzylisatin and p-toluidine (Ikotun et al., 2012 ). The crystal structure of 1-benzyl-3-[(4-methoxyphenyl)imino]indolin-2-one (Fig. 1) is hereby reported.

Figure 1
The molecular structure of 1-benzyl-3-[(4-methoxyphenyl)imino]indolin-2-one showing the atomic labelling; displacement ellipsoids are drawn at the 50% probability level.

In the title compound, the asymmetric unit of compound contains one independent molecule crystallizing in the triclinic space group P $[\overline{1}]$ . The crystal disintegrated at 300 K and the X-ray structure was acquired at room temperature. The benzyl and phenyl rings subtend dihedral angles of 76.08 (7) and 60.70 (6)°, respectively, with the isatin group.

Synthesis and crystallization

N-benzylisatin was prepared according to a literature method (Ikotun et al., 2012). N-Benzylisatin (1.000 g, 4.2194 mmol) was dissolved in 20 ml of methanol. 4-Methoxylaniline (0.5196 g, 4.2194 mmol) was also dissolved in 10 ml of methanol. The two solutions were mixed together while stirring at room temperature with the addition of 6 drops of glacial acetic acid for 8 h. The precipitate was filtered under vacuum, dried and the weight was determined to be 1.0566 g (73%). X-ray-suitable crystals were obtained by recrystallization from dimethylformamide solution after about two weeks.

Refinement

Crystal data, data collection and structure refinement details are summarized in Table 1.

Table 1
Experimental details

Crystal data
Chemical formula	C₂₂H₁₈N₂O₂
M_r	342.38
Crystal system, space group	Triclinic, P $[\overline{1}]$
Temperature (K)	300
a, b, c (Å)	8.8872 (19), 8.8922 (19), 11.772 (3)
α, β, γ (°)	94.374 (6), 110.139 (6), 93.747 (6)
V (Å³)	866.7 (3)
Z	2
Radiation type	Mo Kα
μ (mm⁻¹)	0.09
Crystal size (mm)	0.55 × 0.53 × 0.44

Data collection
Diffractometer	Bruker APEXII DUO (PHOTON 100)
Absorption correction	Multi-scan (SADABS; Krause et al., 2015 )
T_min, T_max	0.358, 0.431
No. of measured, independent and observed [I > 2σ(I)] reflections	24116, 4003, 3219
R_int	0.049
(sin θ/λ)_max (Å⁻¹)	0.651

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.044, 0.109, 1.03
No. of reflections	4003
No. of parameters	237
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.28, −0.18
Computer programs: APEX2 and SAINT (Bruker, 2018 ), SHELXT (Sheldrick, 2015a ), SHELXL (Sheldrick, 2015b ), OLEX2 (Dolomanov et al., 2009 ) and PLATON (Spek, 2020 ).

Structural data

CCDC reference: 2262787

Crystal structure: contains datablock I. DOI: https://doi.org/10.1107/S2414314623004182/bh4074sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2414314623004182/bh4074Isup2.hkl

Supporting information file. DOI: https://doi.org/10.1107/S2414314623004182/bh4074Isup3.cml

checkCIF report

Computing details top

Data collection: APEX2 (Bruker, 2018); cell refinement: SAINT (Bruker, 2018); data reduction: SAINT (Bruker, 2018); program(s) used to solve structure: SHELXT (Sheldrick, 2015a); program(s) used to refine structure: SHELXL (Sheldrick, 2015b); molecular graphics: Olex2 (Dolomanov et al., 2009); software used to prepare material for publication: Olex2 (Dolomanov et al., 2009) and PLATON (Spek, 2020)..

1-Benzyl-3-[(4-methoxyphenyl)imino]indolin-2-one top

Crystal data top

C₂₂H₁₈N₂O₂	Z = 2
M_r = 342.38	F(000) = 360
Triclinic, P1	D_x = 1.312 Mg m⁻³
a = 8.8872 (19) Å	Mo Kα radiation, λ = 0.71073 Å
b = 8.8922 (19) Å	Cell parameters from 9907 reflections
c = 11.772 (3) Å	θ = 2.5–27.5°
α = 94.374 (6)°	µ = 0.09 mm⁻¹
β = 110.139 (6)°	T = 300 K
γ = 93.747 (6)°	Block, orange
V = 866.7 (3) Å³	0.55 × 0.53 × 0.44 mm

Data collection top

Bruker APEXII DUO (PHOTON 100) diffractometer	3219 reflections with I > 2σ(I)
φ and ω scans	R_int = 0.049
Absorption correction: multi-scan (SADABS; Krause et al., 2015)	θ_max = 27.5°, θ_min = 1.9°
T_min = 0.358, T_max = 0.431	h = −11→11
24116 measured reflections	k = −11→11
4003 independent reflections	l = −15→15

Refinement top

Refinement on F²	Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: full	H-atom parameters constrained
R[F² > 2σ(F²)] = 0.044	w = 1/[σ²(F_o²) + (0.0428P)² + 0.2626P] where P = (F_o² + 2F_c²)/3
wR(F²) = 0.109	(Δ/σ)_max < 0.001
S = 1.02	Δρ_max = 0.28 e Å⁻³
4003 reflections	Δρ_min = −0.18 e Å⁻³
237 parameters	Extinction correction: SHELXL2018/3 (Sheldrick 2015b), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
0 restraints	Extinction coefficient: 0.184 (7)
Primary atom site location: dual

Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.

Refinement. Systematic reflection conditions and statistical tests of the data suggested the space group P-1. A solution was obtained readily using XT/XS in APEX2. Hydrogen atoms were placed in idealized positions and were set riding on the respective parent atoms. All non-hydrogen atoms were refined with anisotropic thermal parameters. Absence of additional symmetry and voids were confirmed using PLATON. The structure was refined (weighted least squares refinement on F2) to convergence (Sheldrick, 2008, 2015; Dolomanov, et al., 2009).

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
O1	0.32465 (13)	0.09548 (11)	0.17890 (9)	0.0467 (3)
O2	0.15900 (14)	0.09727 (14)	0.84290 (10)	0.0546 (3)
N1	0.33951 (14)	0.35590 (13)	0.20515 (10)	0.0367 (3)
N2	0.28029 (13)	0.11348 (12)	0.40997 (10)	0.0340 (3)
C1	0.32025 (15)	0.21291 (15)	0.23706 (12)	0.0336 (3)
C2	0.28984 (14)	0.23196 (14)	0.35726 (11)	0.0290 (3)
C3	0.29136 (14)	0.39654 (14)	0.38541 (11)	0.0295 (3)
C4	0.32480 (15)	0.46621 (15)	0.29236 (12)	0.0324 (3)
C5	0.34166 (17)	0.62236 (16)	0.29431 (14)	0.0429 (3)
H5	0.363199	0.667768	0.232234	0.051*
C6	0.32539 (17)	0.70910 (16)	0.39198 (15)	0.0455 (4)
H6	0.335311	0.814188	0.394595	0.055*
C7	0.29483 (17)	0.64298 (16)	0.48527 (14)	0.0429 (3)
H7	0.286015	0.703664	0.550177	0.051*
C8	0.27719 (16)	0.48616 (15)	0.48251 (12)	0.0355 (3)
H8	0.256098	0.441593	0.545095	0.043*
C9	0.37347 (17)	0.38347 (18)	0.09473 (13)	0.0426 (3)
H9A	0.352646	0.486352	0.076706	0.051*
H9B	0.300810	0.315234	0.027033	0.051*
C10	0.54526 (17)	0.36126 (16)	0.10615 (12)	0.0364 (3)
C11	0.5760 (2)	0.24368 (17)	0.03577 (14)	0.0458 (4)
H11	0.490557	0.178863	−0.017936	0.055*
C12	0.7322 (2)	0.2210 (2)	0.04411 (17)	0.0576 (4)
H12	0.751328	0.142265	−0.004234	0.069*
C13	0.8587 (2)	0.3160 (2)	0.12445 (18)	0.0634 (5)
H13	0.963785	0.301025	0.130876	0.076*
C14	0.8301 (2)	0.4332 (2)	0.19530 (17)	0.0612 (5)
H14	0.916046	0.496349	0.250138	0.073*
C15	0.67396 (19)	0.45734 (19)	0.18531 (14)	0.0484 (4)
H15	0.655276	0.538342	0.231865	0.058*
C16	0.24553 (15)	0.11827 (14)	0.51921 (11)	0.0311 (3)
C17	0.10870 (16)	0.17623 (15)	0.52979 (12)	0.0360 (3)
H17	0.039392	0.220029	0.465081	0.043*
C18	0.07458 (16)	0.16936 (16)	0.63595 (13)	0.0372 (3)
H18	−0.017670	0.207542	0.641944	0.045*
C19	0.17839 (17)	0.10545 (15)	0.73296 (12)	0.0370 (3)
C20	0.31359 (17)	0.04389 (16)	0.72204 (13)	0.0403 (3)
H20	0.382694	−0.000043	0.786762	0.048*
C21	0.34513 (16)	0.04796 (15)	0.61558 (12)	0.0360 (3)
H21	0.433457	0.003537	0.607830	0.043*
C22	0.0133 (2)	0.1394 (2)	0.85474 (16)	0.0595 (5)
H22A	−0.076403	0.080458	0.793597	0.089*
H22B	0.005243	0.245081	0.844710	0.089*
H22C	0.012674	0.121264	0.933923	0.089*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.0621 (7)	0.0413 (6)	0.0439 (6)	0.0032 (5)	0.0297 (5)	−0.0034 (5)
O2	0.0610 (7)	0.0759 (8)	0.0391 (6)	0.0185 (6)	0.0293 (5)	0.0136 (5)
N1	0.0435 (6)	0.0387 (6)	0.0353 (6)	0.0060 (5)	0.0217 (5)	0.0099 (5)
N2	0.0413 (6)	0.0296 (6)	0.0364 (6)	0.0042 (5)	0.0197 (5)	0.0051 (4)
C1	0.0334 (7)	0.0367 (7)	0.0335 (7)	0.0044 (5)	0.0151 (5)	0.0045 (5)
C2	0.0283 (6)	0.0302 (6)	0.0306 (6)	0.0040 (5)	0.0125 (5)	0.0035 (5)
C3	0.0267 (6)	0.0293 (6)	0.0335 (6)	0.0047 (5)	0.0109 (5)	0.0060 (5)
C4	0.0285 (6)	0.0342 (7)	0.0368 (7)	0.0063 (5)	0.0130 (5)	0.0084 (5)
C5	0.0419 (8)	0.0374 (8)	0.0553 (9)	0.0070 (6)	0.0212 (7)	0.0185 (7)
C6	0.0401 (8)	0.0275 (7)	0.0694 (10)	0.0055 (6)	0.0193 (7)	0.0067 (7)
C7	0.0409 (8)	0.0341 (7)	0.0533 (9)	0.0053 (6)	0.0175 (7)	−0.0032 (6)
C8	0.0370 (7)	0.0341 (7)	0.0374 (7)	0.0035 (5)	0.0159 (6)	0.0017 (5)
C9	0.0452 (8)	0.0564 (9)	0.0318 (7)	0.0070 (7)	0.0178 (6)	0.0154 (6)
C10	0.0448 (7)	0.0424 (8)	0.0281 (6)	0.0042 (6)	0.0188 (6)	0.0116 (5)
C11	0.0556 (9)	0.0420 (8)	0.0424 (8)	0.0003 (7)	0.0214 (7)	0.0037 (6)
C12	0.0699 (11)	0.0520 (10)	0.0632 (11)	0.0179 (8)	0.0368 (9)	0.0071 (8)
C13	0.0488 (9)	0.0777 (13)	0.0722 (12)	0.0166 (9)	0.0287 (9)	0.0157 (10)
C14	0.0473 (9)	0.0743 (12)	0.0554 (10)	−0.0031 (8)	0.0124 (8)	0.0016 (9)
C15	0.0524 (9)	0.0552 (9)	0.0375 (8)	0.0015 (7)	0.0179 (7)	−0.0024 (7)
C16	0.0382 (7)	0.0240 (6)	0.0341 (6)	0.0004 (5)	0.0172 (5)	0.0031 (5)
C17	0.0364 (7)	0.0363 (7)	0.0376 (7)	0.0058 (5)	0.0142 (6)	0.0096 (6)
C18	0.0329 (7)	0.0392 (7)	0.0442 (8)	0.0048 (5)	0.0193 (6)	0.0043 (6)
C19	0.0429 (7)	0.0380 (7)	0.0336 (7)	0.0012 (6)	0.0183 (6)	0.0027 (5)
C20	0.0449 (8)	0.0434 (8)	0.0349 (7)	0.0121 (6)	0.0143 (6)	0.0099 (6)
C21	0.0391 (7)	0.0323 (7)	0.0415 (7)	0.0082 (5)	0.0191 (6)	0.0055 (6)
C22	0.0575 (10)	0.0811 (13)	0.0523 (10)	0.0020 (9)	0.0361 (8)	0.0053 (9)

Geometric parameters (Å, º) top

O1—C1	1.2147 (16)	C10—C15	1.387 (2)
O2—C19	1.3697 (16)	C11—H11	0.9300
O2—C22	1.4197 (19)	C11—C12	1.387 (2)
N1—C1	1.3695 (17)	C12—H12	0.9300
N1—C4	1.4102 (17)	C12—C13	1.376 (3)
N1—C9	1.4663 (17)	C13—H13	0.9300
N2—C2	1.2753 (16)	C13—C14	1.376 (3)
N2—C16	1.4205 (16)	C14—H14	0.9300
C1—C2	1.5286 (17)	C14—C15	1.384 (2)
C2—C3	1.4739 (17)	C15—H15	0.9300
C3—C4	1.4056 (18)	C16—C17	1.3915 (18)
C3—C8	1.3895 (18)	C16—C21	1.3966 (19)
C4—C5	1.3843 (19)	C17—H17	0.9300
C5—H5	0.9300	C17—C18	1.3884 (19)
C5—C6	1.390 (2)	C18—H18	0.9300
C6—H6	0.9300	C18—C19	1.386 (2)
C6—C7	1.381 (2)	C19—C20	1.3934 (19)
C7—H7	0.9300	C20—H20	0.9300
C7—C8	1.3897 (19)	C20—C21	1.3776 (19)
C8—H8	0.9300	C21—H21	0.9300
C9—H9A	0.9700	C22—H22A	0.9600
C9—H9B	0.9700	C22—H22B	0.9600
C9—C10	1.513 (2)	C22—H22C	0.9600
C10—C11	1.384 (2)

C19—O2—C22	118.34 (12)	C10—C11—C12	121.00 (15)
C1—N1—C4	110.94 (10)	C12—C11—H11	119.5
C1—N1—C9	122.28 (12)	C11—C12—H12	120.2
C4—N1—C9	126.77 (12)	C13—C12—C11	119.51 (16)
C2—N2—C16	122.11 (11)	C13—C12—H12	120.2
O1—C1—N1	125.81 (12)	C12—C13—H13	119.9
O1—C1—C2	127.73 (12)	C14—C13—C12	120.16 (16)
N1—C1—C2	106.44 (11)	C14—C13—H13	119.9
N2—C2—C1	117.81 (11)	C13—C14—H14	119.9
N2—C2—C3	136.54 (12)	C13—C14—C15	120.28 (16)
C3—C2—C1	105.47 (10)	C15—C14—H14	119.9
C4—C3—C2	106.74 (11)	C10—C15—H15	119.9
C8—C3—C2	133.75 (12)	C14—C15—C10	120.27 (15)
C8—C3—C4	119.38 (12)	C14—C15—H15	119.9
C3—C4—N1	110.38 (11)	C17—C16—N2	122.85 (12)
C5—C4—N1	128.15 (12)	C17—C16—C21	118.87 (12)
C5—C4—C3	121.46 (12)	C21—C16—N2	117.96 (11)
C4—C5—H5	121.1	C16—C17—H17	119.7
C4—C5—C6	117.89 (13)	C18—C17—C16	120.69 (12)
C6—C5—H5	121.1	C18—C17—H17	119.7
C5—C6—H6	119.2	C17—C18—H18	120.1
C7—C6—C5	121.59 (13)	C19—C18—C17	119.80 (12)
C7—C6—H6	119.2	C19—C18—H18	120.1
C6—C7—H7	119.9	O2—C19—C18	124.58 (12)
C6—C7—C8	120.26 (13)	O2—C19—C20	115.57 (12)
C8—C7—H7	119.9	C18—C19—C20	119.85 (12)
C3—C8—C7	119.41 (13)	C19—C20—H20	119.9
C3—C8—H8	120.3	C21—C20—C19	120.15 (13)
C7—C8—H8	120.3	C21—C20—H20	119.9
N1—C9—H9A	109.0	C16—C21—H21	119.7
N1—C9—H9B	109.0	C20—C21—C16	120.53 (12)
N1—C9—C10	112.92 (11)	C20—C21—H21	119.7
H9A—C9—H9B	107.8	O2—C22—H22A	109.5
C10—C9—H9A	109.0	O2—C22—H22B	109.5
C10—C9—H9B	109.0	O2—C22—H22C	109.5
C11—C10—C9	119.80 (13)	H22A—C22—H22B	109.5
C11—C10—C15	118.76 (14)	H22A—C22—H22C	109.5
C15—C10—C9	121.44 (13)	H22B—C22—H22C	109.5
C10—C11—H11	119.5

O1—C1—C2—N2	6.2 (2)	C5—C6—C7—C8	−0.9 (2)
O1—C1—C2—C3	−177.95 (13)	C6—C7—C8—C3	0.3 (2)
O2—C19—C20—C21	−179.24 (13)	C8—C3—C4—N1	178.07 (11)
N1—C1—C2—N2	−174.78 (11)	C8—C3—C4—C5	−0.95 (19)
N1—C1—C2—C3	1.07 (13)	C9—N1—C1—O1	−1.9 (2)
N1—C4—C5—C6	−178.48 (13)	C9—N1—C1—C2	179.07 (11)
N1—C9—C10—C11	113.49 (15)	C9—N1—C4—C3	179.82 (12)
N1—C9—C10—C15	−67.07 (18)	C9—N1—C4—C5	−1.2 (2)
N2—C2—C3—C4	172.91 (14)	C9—C10—C11—C12	179.78 (14)
N2—C2—C3—C8	−2.5 (2)	C9—C10—C15—C14	179.05 (14)
N2—C16—C17—C18	175.73 (12)	C10—C11—C12—C13	0.6 (3)
N2—C16—C21—C20	−177.48 (12)	C11—C10—C15—C14	−1.5 (2)
C1—N1—C4—C3	−1.19 (15)	C11—C12—C13—C14	−0.4 (3)
C1—N1—C4—C5	177.75 (13)	C12—C13—C14—C15	−0.7 (3)
C1—N1—C9—C10	−74.72 (17)	C13—C14—C15—C10	1.7 (3)
C1—C2—C3—C4	−1.74 (13)	C15—C10—C11—C12	0.3 (2)
C1—C2—C3—C8	−177.20 (13)	C16—N2—C2—C1	−177.27 (11)
C2—N2—C16—C17	56.00 (18)	C16—N2—C2—C3	8.6 (2)
C2—N2—C16—C21	−130.53 (13)	C16—C17—C18—C19	0.6 (2)
C2—C3—C4—N1	1.84 (14)	C17—C16—C21—C20	−3.7 (2)
C2—C3—C4—C5	−177.19 (12)	C17—C18—C19—O2	177.83 (13)
C2—C3—C8—C7	175.61 (13)	C17—C18—C19—C20	−2.1 (2)
C3—C4—C5—C6	0.4 (2)	C18—C19—C20—C21	0.7 (2)
C4—N1—C1—O1	179.06 (13)	C19—C20—C21—C16	2.3 (2)
C4—N1—C1—C2	0.02 (14)	C21—C16—C17—C18	2.3 (2)
C4—N1—C9—C10	104.17 (15)	C22—O2—C19—C18	8.2 (2)
C4—C3—C8—C7	0.60 (19)	C22—O2—C19—C20	−171.81 (14)
C4—C5—C6—C7	0.6 (2)

Acknowledgements

The US National Science Foundation (CHE-1900549) is thanked for supporting the X-ray analysis carried out at Texas A & M University, College Station, Texas, USA.

Funding information

The authors thank the Tertiary Education Trust Fund (TETFund), Nigeria for sponsoring this work.

References

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