2-(5-Methyl-1-benzo­furan-3-yl)-N-(2-phenyl­eth­yl)acetamide

Ramprasad, N.; Gowda, K.V.A.; Gowda, R.; Basanagouda, M.; Kantharaj, K.S.; Gowda, G.V.J.

doi:10.1107/S2414314617002000

organic compounds

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ISSN: 2414-3146

Volume 2| Part 2| February 2017| x170200

https://doi.org/10.1107/S2414314617002000

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2-(5-Methyl-1-benzofuran-3-yl)-N-(2-phenylethyl)acetamide

N. Ramprasad,^a K. V. Arjuna Gowda,^b ^* Ramakrishna Gowda,^c Mahantesha Basanagouda,^d K. S. Kantharaj ^e and G. V. Jagadeesha Gowda ^f

^aDepartment of Physics, Govt. First Grade College, Mulbagal, Kolar Dist 563 131, Karnataka, India, ^bDepartment of Physics, Govt. College for Women, Mandya 571 401, Karnataka, India, ^cDepartment of Physics, Govt. College for Women, Kolar 563 101, Karnataka, India, ^dDepartment of Chemistry, P.C. Jabin Science College, Hubli 580 031, Karnataka, India, ^eDepartment of Physics, Govt. First Grade College, Malur, Kolar 563 160, Karnataka, India, and ^fDepartment of Physics, Sapthagiri College of Engineering, Bangalore 560 057, Karnataka, India
^*Correspondence e-mail: kvarjunagowda@gmail.com

Edited by J. Simpson, University of Otago, New Zealand (Received 31 January 2017; accepted 7 February 2017; online 10 February 2017)

The title compound, C₁₉H₁₉NO₂, is non-planar with the phenyl ring of the phenethylacetamide residue inclined to the benzofuran ring system by 84.8 (3)°. The methyl group lies in the plane of the fused ring system [C—C—C—C torsion angle = −179.6 (3)°]. In the crystal, N—H⋯O hydrogen bonds link the molecules into chains along the a-axis direction. π–π stacking interactions with a centroid-to-centroid distances of 3.497 (3) Å further stabilize the structure, stacking the molecules along a.

Keywords: crystal structure; benzofuran; hydrogen bonding; π–π stacking.

CCDC reference: 1503758

Structure description

Benzofuran derivatives with an amide linkage have attracted attention due to their wide range of biological activities. These include acting as melatonin receptor selective ligands (Wallez et al., 2002 ), glycogen synthase kinase 3β inhibitors, which suppress proliferation and survival of pancreatic cancer cells (Gaisina et al., 2009 ), and ischemic cell death inhibitors (Suh et al., 2010 ). They are also used as antitubercular and antifungal (Telvekar et al., 2012 ) or anticonvulsant agents (Shakya et al., 2016 ). They inhibit monoamine oxidase (Pisani et al., 2013 ), the hepatitis C virus (Bowman et al., 2015 ) and NF-kB activity (Choi et al., 2016 ). Other pharmaceutical applications include the treatment of cognitive disorders (Mazurov et al., 2012 ) and as anti-oestrogen breast cancer agents (Li et al., 2013 ). Chemically they are used as intermediates for the synthesis of morphine alkaloids (France et al., 2008 ).

The title compound (Fig. 1) is non-planar. The C14–C18 phenyl ring of the phenethylacetamide residue is inclined to the planar benzofuran ring system by 84.8 (3)°. The r.m.s. deviation from the plane through the ten atoms of the benzofuran ring system is 0.011 Å. The molecular structure is similar to that observed for 2-(5-methyl-1-benzofuran-3-yl)acetic acid (Ramprasad et al., 2016 ).

Figure 1
The molecular structure of the title compound, showing 40% probability displacement ellipsoids and the atom numbering.

In the crystal, N1—H1⋯O2 hydrogen bonds (Table 1) link the molecules into chains along the a-axis direction. A π–π stacking interaction [Cg⋯Cgⁱⁱ = 3.497 (3) Å, Cg is the centroid of the O1/C5/C6/C8/C9 ring; symmetry code: (ii) 2 − x, −y, 2 − z] further stabilizes the structure, Fig. 2, stacking the molecules along a.

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1⋯O2ⁱ	0.79 (3)	2.06 (3)	2.849 (3)	173 (3)
Symmetry code: (i) $[x-{\script{1\over 2}}, -y+{\script{1\over 2}}, z]$ .

Figure 2
Packing diagram viewed along the b axis, with hydrogen bonds drawn as dashed lines. Ring centroids are shown as coloured spheres and π–π contacts as dotted lines.

Synthesis and crystallization

5-Methyl-benzofuran-3-acetic acid (10 mmol) (Basanagouda et al., 2015 ; Uriarte et al., 1995 ) was refluxed with phenylethylamine (10 mmol) in benzene (30 ml) for 7 h (monitored by TLC). The solvent was removed to obtain a colourless solid, which was crystallized from a mixture of benzene and petroleum ether (1:1). Crystals suitable for diffraction studies were obtained by the slow evaporation of a solvent mixture of benzene and petroleum ether (1:1).

Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2.

Table 2
Experimental details

Crystal data
Chemical formula	C₁₉H₁₉NO₂
M_r	293.35
Crystal system, space group	Monoclinic, P2₁/a
Temperature (K)	293
a, b, c (Å)	9.440 (6), 14.6051 (15), 12.321 (2)
β (°)	105.68 (3)
V (Å³)	1635.5 (10)
Z	4
Radiation type	Cu Kα
μ (mm⁻¹)	0.61
Crystal size (mm)	0.30 × 0.20 × 0.20

Data collection
Diffractometer	Enraf–Nonius CAD-4
Absorption correction	ψ scan (CAD-4 Software; Enraf–Nonius, 1989 )
T_min, T_max	0.884, 0.983
No. of measured, independent and observed [I > 2σ(I)] reflections	2962, 2777, 1611
R_int	0.019
(sin θ/λ)_max (Å⁻¹)	0.588

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.063, 0.169, 1.04
No. of reflections	2777
No. of parameters	205
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.22, −0.20
Computer programs: CAD-4 Software (Enraf–Nonius, 1989), XCAD4 (Harms & Wocadlo, 1995 ), SHELXS97 and SHELXL97 (Sheldrick, 2008 ), ORTEP-3 for Windows (Farrugia, 2012 ) and Mercury (Macrae et al., 2008 ).

Structural data

CCDC reference: 1503758

Crystal structure: contains datablock I. DOI: https://doi.org/10.1107/S2414314617002000/sj4086sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2414314617002000/sj4086Isup2.hkl

Supporting information file. DOI: https://doi.org/10.1107/S2414314617002000/sj4086Isup3.cml

checkCIF report

Computing details top

Data collection: CAD-4 Software (Enraf–Nonius, 1989); cell refinement: CAD-4 Software (Enraf–Nonius, 1989); data reduction: XCAD4 (Harms & Wocadlo, 1995); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012) and Mercury (Macrae et al., 2008); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

2-(5-Methyl-1-benzofuran-3-yl)-N-(2-phenylethyl)acetamide top

Crystal data top

C₁₉H₁₉NO₂	F(000) = 624
M_r = 293.35	D_x = 1.191 Mg m⁻³
Monoclinic, P2₁/a	Melting point: 374 K
Hall symbol: -P 2yab	Cu Kα radiation, λ = 1.54180 Å
a = 9.440 (6) Å	Cell parameters from 25 reflections
b = 14.6051 (15) Å	θ = 20–30°
c = 12.321 (2) Å	µ = 0.61 mm⁻¹
β = 105.68 (3)°	T = 293 K
V = 1635.5 (10) Å³	Block, colourless
Z = 4	0.30 × 0.20 × 0.20 mm

Data collection top

Enraf–Nonius CAD-4 diffractometer	1611 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	R_int = 0.019
Graphite monochromator	θ_max = 65.0°, θ_min = 3.7°
ω–2τ scan	h = 0→11
Absorption correction: ψ scan (CAD-4 Software; Enraf–Nonius, 1989)	k = 0→17
T_min = 0.884, T_max = 0.983	l = −14→13
2962 measured reflections	2 standard reflections every 3600 min
2777 independent reflections	intensity decay: none

Refinement top

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)] = 0.063	H atoms treated by a mixture of independent and constrained refinement
wR(F²) = 0.169	w = 1/[σ²(F_o²) + (0.0836P)² + 0.197P] where P = (F_o² + 2F_c²)/3
S = 1.04	(Δ/σ)_max < 0.001
2777 reflections	Δρ_max = 0.22 e Å⁻³
205 parameters	Δρ_min = −0.20 e Å⁻³
0 restraints	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0138 (11)

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. 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 > 2sigma(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

	x	y	z	U_iso*/U_eq
C1	1.4210 (5)	0.2541 (3)	1.2438 (3)	0.1106 (13)
H1A	1.4362	0.2308	1.3189	0.166*
H1B	1.3544	0.3051	1.2328	0.166*
H1C	1.5134	0.2737	1.2331	0.166*
C2	1.3564 (4)	0.1798 (2)	1.1596 (3)	0.0759 (9)
C3	1.4336 (4)	0.0988 (3)	1.1569 (3)	0.0846 (11)
H3	1.5253	0.0914	1.2082	0.101*
C4	1.3806 (4)	0.0296 (3)	1.0820 (3)	0.0785 (10)
H4	1.4336	−0.0241	1.0817	0.094*
C5	1.2452 (3)	0.0433 (2)	1.0074 (3)	0.0628 (8)
C6	1.1619 (3)	0.12179 (19)	1.0061 (2)	0.0563 (8)
C7	1.2192 (3)	0.1905 (2)	1.0831 (3)	0.0671 (8)
H7	1.1656	0.2438	1.0836	0.081*
C8	1.0405 (3)	0.0264 (2)	0.8746 (3)	0.0699 (9)
H8	0.9679	0.0007	0.8160	0.084*
C9	1.0287 (3)	0.10883 (19)	0.9184 (2)	0.0582 (8)
C10	0.8999 (3)	0.1722 (2)	0.8871 (3)	0.0641 (8)
H10A	0.8761	0.1916	0.9553	0.077*
H10B	0.8159	0.1388	0.8416	0.077*
C11	0.9241 (3)	0.25580 (18)	0.8229 (2)	0.0516 (7)
C12	0.8114 (3)	0.39129 (18)	0.7207 (3)	0.0611 (8)
H12A	0.9075	0.3964	0.7069	0.073*
H12B	0.7981	0.4444	0.7643	0.073*
C13	0.6974 (4)	0.3930 (2)	0.6110 (3)	0.0842 (10)
H13A	0.6012	0.3994	0.6241	0.101*
H13B	0.6992	0.3354	0.5721	0.101*
C14	0.7222 (4)	0.4706 (2)	0.5379 (3)	0.0712 (9)
C15	0.6933 (5)	0.5581 (3)	0.5605 (3)	0.0926 (11)
H15	0.6502	0.5700	0.6186	0.111*
C16	0.7264 (5)	0.6302 (3)	0.4992 (4)	0.1059 (13)
H16	0.7048	0.6898	0.5163	0.127*
C17	0.7900 (5)	0.6152 (3)	0.4146 (4)	0.1068 (14)
H17	0.8148	0.6640	0.3747	0.128*
C18	0.8165 (6)	0.5295 (4)	0.3895 (4)	0.1203 (15)
H18	0.8575	0.5184	0.3300	0.144*
C19	0.7842 (5)	0.4564 (3)	0.4501 (4)	0.1108 (14)
H19	0.8047	0.3971	0.4315	0.133*
N1	0.8092 (2)	0.31022 (16)	0.7869 (2)	0.0546 (7)
O1	1.1717 (2)	−0.01657 (14)	0.92533 (19)	0.0737 (6)
O2	1.04377 (19)	0.27316 (14)	0.8051 (2)	0.0804 (7)
H1	0.736 (4)	0.290 (2)	0.797 (3)	0.077 (10)*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.105 (3)	0.123 (3)	0.099 (3)	−0.008 (3)	0.019 (2)	−0.014 (3)
C2	0.072 (2)	0.085 (2)	0.075 (2)	0.0026 (19)	0.0275 (18)	0.0129 (19)
C3	0.063 (2)	0.104 (3)	0.085 (3)	0.018 (2)	0.0183 (19)	0.024 (2)
C4	0.068 (2)	0.084 (2)	0.089 (2)	0.0300 (19)	0.0306 (19)	0.025 (2)
C5	0.0632 (19)	0.0623 (18)	0.071 (2)	0.0153 (15)	0.0329 (16)	0.0176 (16)
C6	0.0538 (17)	0.0561 (17)	0.0680 (19)	0.0106 (14)	0.0321 (15)	0.0174 (15)
C7	0.0630 (19)	0.0658 (19)	0.081 (2)	0.0104 (16)	0.0336 (17)	0.0132 (18)
C8	0.066 (2)	0.067 (2)	0.079 (2)	0.0054 (16)	0.0227 (17)	0.0184 (17)
C9	0.0550 (17)	0.0561 (18)	0.071 (2)	0.0068 (14)	0.0301 (16)	0.0203 (15)
C10	0.0429 (15)	0.0698 (19)	0.085 (2)	0.0051 (13)	0.0267 (15)	0.0200 (16)
C11	0.0365 (13)	0.0570 (16)	0.0650 (17)	0.0033 (12)	0.0200 (12)	0.0083 (14)
C12	0.0465 (16)	0.0534 (16)	0.082 (2)	0.0024 (13)	0.0152 (15)	0.0128 (15)
C13	0.092 (2)	0.075 (2)	0.075 (2)	−0.016 (2)	0.0035 (19)	0.0106 (18)
C14	0.080 (2)	0.059 (2)	0.068 (2)	−0.0005 (17)	0.0083 (17)	0.0073 (17)
C15	0.117 (3)	0.073 (2)	0.090 (3)	0.010 (2)	0.032 (2)	0.013 (2)
C16	0.140 (4)	0.068 (3)	0.107 (3)	0.013 (2)	0.027 (3)	0.016 (2)
C17	0.133 (4)	0.089 (3)	0.092 (3)	−0.004 (3)	0.018 (3)	0.034 (2)
C18	0.153 (4)	0.126 (4)	0.097 (3)	0.015 (3)	0.060 (3)	0.023 (3)
C19	0.159 (4)	0.084 (3)	0.096 (3)	0.026 (3)	0.045 (3)	0.012 (2)
N1	0.0339 (12)	0.0570 (14)	0.0766 (17)	0.0029 (11)	0.0212 (11)	0.0144 (12)
O1	0.0800 (15)	0.0640 (13)	0.0849 (15)	0.0187 (12)	0.0356 (12)	0.0125 (12)
O2	0.0422 (11)	0.0794 (14)	0.1325 (19)	0.0128 (10)	0.0457 (12)	0.0399 (13)

Geometric parameters (Å, º) top

C1—C2	1.511 (5)	C11—O2	1.234 (3)
C1—H1A	0.9600	C11—N1	1.321 (3)
C1—H1B	0.9600	C12—N1	1.441 (3)
C1—H1C	0.9600	C12—C13	1.483 (4)
C2—C7	1.389 (4)	C12—H12A	0.9700
C2—C3	1.396 (5)	C12—H12B	0.9700
C3—C4	1.369 (5)	C13—C14	1.504 (4)
C3—H3	0.9300	C13—H13A	0.9700
C4—C5	1.372 (4)	C13—H13B	0.9700
C4—H4	0.9300	C14—C15	1.352 (5)
C5—O1	1.375 (4)	C14—C19	1.377 (5)
C5—C6	1.387 (4)	C15—C16	1.380 (5)
C6—C7	1.386 (4)	C15—H15	0.9300
C6—C9	1.432 (4)	C16—C17	1.355 (6)
C7—H7	0.9300	C16—H16	0.9300
C8—C9	1.337 (4)	C17—C18	1.329 (6)
C8—O1	1.378 (3)	C17—H17	0.9300
C8—H8	0.9300	C18—C19	1.383 (6)
C9—C10	1.493 (4)	C18—H18	0.9300
C10—C11	1.505 (4)	C19—H19	0.9300
C10—H10A	0.9700	N1—H1	0.79 (3)
C10—H10B	0.9700

C2—C1—H1A	109.5	O2—C11—C10	122.4 (2)
C2—C1—H1B	109.5	N1—C11—C10	115.9 (2)
H1A—C1—H1B	109.5	N1—C12—C13	114.3 (2)
C2—C1—H1C	109.5	N1—C12—H12A	108.7
H1A—C1—H1C	109.5	C13—C12—H12A	108.7
H1B—C1—H1C	109.5	N1—C12—H12B	108.7
C7—C2—C3	118.4 (4)	C13—C12—H12B	108.7
C7—C2—C1	121.0 (3)	H12A—C12—H12B	107.6
C3—C2—C1	120.6 (3)	C12—C13—C14	111.5 (3)
C4—C3—C2	123.0 (3)	C12—C13—H13A	109.3
C4—C3—H3	118.5	C14—C13—H13A	109.3
C2—C3—H3	118.5	C12—C13—H13B	109.3
C3—C4—C5	116.6 (3)	C14—C13—H13B	109.3
C3—C4—H4	121.7	H13A—C13—H13B	108.0
C5—C4—H4	121.7	C15—C14—C19	117.1 (3)
C4—C5—O1	126.3 (3)	C15—C14—C13	121.1 (3)
C4—C5—C6	123.5 (3)	C19—C14—C13	121.6 (3)
O1—C5—C6	110.2 (3)	C14—C15—C16	121.4 (4)
C7—C6—C5	118.3 (3)	C14—C15—H15	119.3
C7—C6—C9	135.4 (3)	C16—C15—H15	119.3
C5—C6—C9	106.2 (3)	C17—C16—C15	120.7 (4)
C6—C7—C2	120.2 (3)	C17—C16—H16	119.7
C6—C7—H7	119.9	C15—C16—H16	119.7
C2—C7—H7	119.9	C18—C17—C16	118.8 (4)
C9—C8—O1	112.9 (3)	C18—C17—H17	120.6
C9—C8—H8	123.5	C16—C17—H17	120.6
O1—C8—H8	123.5	C17—C18—C19	121.2 (4)
C8—C9—C6	105.8 (3)	C17—C18—H18	119.4
C8—C9—C10	127.2 (3)	C19—C18—H18	119.4
C6—C9—C10	127.0 (3)	C14—C19—C18	120.7 (4)
C9—C10—C11	114.2 (2)	C14—C19—H19	119.6
C9—C10—H10A	108.7	C18—C19—H19	119.6
C11—C10—H10A	108.7	C11—N1—C12	123.3 (2)
C9—C10—H10B	108.7	C11—N1—H1	113 (2)
C11—C10—H10B	108.7	C12—N1—H1	123 (2)
H10A—C10—H10B	107.6	C5—O1—C8	104.9 (2)
O2—C11—N1	121.6 (3)

C7—C2—C3—C4	0.2 (5)	C6—C9—C10—C11	75.3 (4)
C1—C2—C3—C4	−179.6 (3)	C9—C10—C11—O2	−4.8 (4)
C2—C3—C4—C5	0.3 (5)	C9—C10—C11—N1	175.4 (3)
C3—C4—C5—O1	179.8 (3)	N1—C12—C13—C14	−170.0 (3)
C3—C4—C5—C6	−0.8 (5)	C12—C13—C14—C15	−73.6 (4)
C4—C5—C6—C7	0.9 (4)	C12—C13—C14—C19	101.9 (4)
O1—C5—C6—C7	−179.7 (2)	C19—C14—C15—C16	−0.9 (6)
C4—C5—C6—C9	−178.9 (3)	C13—C14—C15—C16	174.9 (3)
O1—C5—C6—C9	0.5 (3)	C14—C15—C16—C17	−0.4 (7)
C5—C6—C7—C2	−0.3 (4)	C15—C16—C17—C18	1.8 (7)
C9—C6—C7—C2	179.4 (3)	C16—C17—C18—C19	−1.9 (8)
C3—C2—C7—C6	−0.2 (4)	C15—C14—C19—C18	0.7 (6)
C1—C2—C7—C6	179.6 (3)	C13—C14—C19—C18	−175.0 (4)
O1—C8—C9—C6	−0.5 (3)	C17—C18—C19—C14	0.7 (8)
O1—C8—C9—C10	−177.4 (2)	O2—C11—N1—C12	2.5 (4)
C7—C6—C9—C8	−179.8 (3)	C10—C11—N1—C12	−177.7 (3)
C5—C6—C9—C8	0.0 (3)	C13—C12—N1—C11	123.3 (3)
C7—C6—C9—C10	−2.8 (5)	C4—C5—O1—C8	178.6 (3)
C5—C6—C9—C10	176.9 (3)	C6—C5—O1—C8	−0.8 (3)
C8—C9—C10—C11	−108.4 (3)	C9—C8—O1—C5	0.8 (3)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···O2ⁱ	0.79 (3)	2.06 (3)	2.849 (3)	173 (3)

Symmetry code: (i) x−1/2, −y+1/2, z.

Acknowledgements

The authors thank the SAIF IIT Madras, Chennai, India, for the data collection.

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