2-(4-Chloro­phen­yl)-N-(3,4-di­fluoro­phen­yl)acetamide

Praveen, A.S.; Yathirajan, H.S.; Jasinski, J.P.; Keeley, A.C.; Narayana, B.; Sarojini, B.K.

doi:10.1107/S1600536813014165

organic compounds

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ISSN: 2056-9890

Volume 69| Part 6| June 2013| Pages o996-o997

doi:10.1107/S1600536813014165

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2-(4-Chlorophenyl)-N-(3,4-difluorophenyl)acetamide

A. S. Praveen,^a H. S. Yathirajan,^a Jerry P. Jasinski,^b ^* Amanda C. Keeley,^b B. Narayana ^c and B. K. Sarojini ^d

^aDepartment of Studies in Chemistry, University of Mysore, Manasagangotri, Mysore 570 006, India, ^bDepartment of Chemistry, Keene State College, 229 Main Street, Keene, NH 03435-2001, USA, ^cDepartment of Studies in Chemistry, Mangalore University, Mangalagangotri 574 199, India, and ^dDepartment of Chemistry, P.A. College of Engineering, Nadupadavu, Mangalore 574 153, India
^*Correspondence e-mail: jjasinski@keene.edu

(Received 19 May 2013; accepted 21 May 2013; online 31 May 2013)

In the title compound, C₁₄H₁₀ClF₂NO, the dihedral angle between the mean planes of the 4-chlorophenyl and 3,4-difluorophenyl rings is 65.2 (1)°. These two planes are twisted by 83.5 (5) and 38.9 (9)°, respectively, from that of the acetamide group. In the crystal, N—H⋯O hydrogen bonds form infinite chains along [100]. Weak C—H⋯O and C—H⋯F interactions are also observed and stack molecules along the b axis.

Related literature

For the structural similarity of N-substituted 2-arylacetamides to the lateral chain of natural benzylpenicillin, see: Mijin & Marinkovic (2006 ); Mijin et al. (2008 ). For the coordination abilities of amides, see: Wu et al. (2008 , 2010 ). For related structures, see: Praveen et al. (2011a ,b ,c , 2012 ). For standard bond lengths, see: Allen et al. (1987 ).

Experimental

Crystal data

C₁₄H₁₀ClF₂NO
M_r = 281.68
Orthorhombic, P 2₁ 2₁ 2₁
a = 4.8935 (5) Å
b = 5.8995 (6) Å
c = 42.572 (4) Å
V = 1229.0 (2) Å³
Z = 4
Cu Kα radiation
μ = 2.92 mm⁻¹
T = 173 K
0.36 × 0.18 × 0.08 mm

Data collection

Agilent Xcalibur (Eos, Gemini) diffractometer
Absorption correction: multi-scan (CrysAlis PRO and CrysAlis RED; Agilent, 2012 ) T_min = 0.608, T_max = 1.000
7056 measured reflections
2358 independent reflections
2293 reflections with I > 2σ(I)
R_int = 0.036

Refinement

R[F² > 2σ(F²)] = 0.042
wR(F²) = 0.111
S = 1.14
2358 reflections
172 parameters
H-atom parameters constrained
Δρ_max = 0.42 e Å⁻³
Δρ_min = −0.28 e Å⁻³
Absolute structure: Flack x determined using 852 quotients [(I+)−(I−)]/[(I+)+(I−)] (Parsons & Flack, 2004 ).
Flack parameter: −0.003 (14)

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1⋯O1ⁱ	0.88	1.97	2.854 (4)	177
C5—H5⋯O1ⁱⁱ	0.95	2.63	3.307 (4)	129
C14—H14⋯F1ⁱⁱⁱ	0.95	2.69	3.615 (5)	164
Symmetry codes: (i) x+1, y, z; (ii) x, y+1, z; (iii) x-1, y+1, z.

Data collection: CrysAlis PRO (Agilent, 2012); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL2012 (Sheldrick, 2008); molecular graphics: OLEX2 (Dolomanov et al., 2009 ); software used to prepare material for publication: OLEX2 (Dolomanov et al., 2009).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536813014165/sj5323sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536813014165/sj5323Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536813014165/sj5323Isup3.cml

checkCIF report

Comment top

N-Substituted 2-arylacetamides are very interesting compounds because of their structural similarity to the lateral chain of natural benzylpenicillin (Mijin et al., 2006, 2008). Amides are also used as ligands due to their excellent coordination abilities (Wu et al., 2008, 2010). Crystal structures of some acetamide derivatives viz., N-(3-chloro-4-fluorophenyl)-2-(naphthalen-1-yl)acetamide (Praveen et al., 2011a), N-(4-chloro-1,3-benzothiazol-2-yl)-2- (3-methylphenyl)acetamide monohydrate (Praveen et al., 2011b), N-(3-chloro-4-fluorophenyl)-2,2-diphenylacetamide (Praveen et al., 2011c) and N-(4,6-dimethoxypyrimidin-2-yl)-2-(3-methylphenyl)acetamide (Praveen et al., 2012) have been reported. In view of the importance of amides, we report here the crystal structure of the title compound, C₁₄H₁₀ClF₂NO, (I).

In (I) the dihedral angle between the mean planes of the 4-chlorophenyl and 3,4-difluorophenyl rings is 65.2 (1)° (Fig. 1). These two planes are twisted by 83.5 (5)° and 38.9 (9)°, respectively, from that of the acetamide group. Bond lengths are in normal ranges (Allen et al., 1987). In the crystal, N—H···O hydrogen bonds are observed forming infinite chains along [100] (Fig. 2). Weak C5–H5···O1 and C14–H14···F1 intermolecular interactions are also observed, Table 1, stacking molecules along the b axis and contributing to the packing stability.

Related literature top

For the structural similarity of N-substituted 2-arylacetamides to the lateral chain of natural benzylpenicillin, see: Mijin & Marinkovic (2006); Mijin et al. (2008). For the coordination abilities of amides, see: Wu et al. (2008, 2010). For related structures, see: Praveen et al. (2011a,b,c, 2012). For standard bond lengths, see: Allen et al. (1987).

Experimental top

4-Chlorophenylacetic acid (0.168 g, 1 mmol), 3,4-difluoro aniline (0.129 g, 1 mmol) and 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride (1.0 g, 0.01 mol) were dissolved in dichloromethane (20 mL). The mixture was stirred in presence of triethylamine at 273 K for about 3 h. The contents were poured into 100 ml of ice-cold aqueous hydrochloric acid with stirring and extracted thrice with dichloromethane. The organic layer was washed with saturated NaHCO₃ solution and brine solution, dried and concentrated under reduced pressure to give the title compound (I). Single crystals were grown from a dichloromethane and ethyl acetate (1:1) mixture by the slow evaporation method (m.p.: 394–396 K).

Computing details top

Data collection: CrysAlis PRO (Agilent, 2012); cell refinement: CrysAlis PRO (Agilent, 2012); data reduction: CrysAlis PRO (Agilent, 2012); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2012 (Sheldrick, 2008); molecular graphics: OLEX2 (Dolomanov et al., 2009); software used to prepare material for publication: OLEX2 (Dolomanov et al., 2009).

Figures top

	Fig. 1. Molecular structure of the title compound showing the atom labeling scheme and 30% probability displacement ellipsoids.
	Fig. 2. Packing diagram of the title compound viewed along the b axis. Dashed lines indicate N—H···O hydrogen bonds forming infinite chains along (100). H atoms not involved in hydrogen bonding have been deleted for clarity.
	Fig. 3. Synthesis of (I).

2-(4-Chlorophenyl)-N-(3,4-difluorophenyl)acetamide top

Crystal data top

C₁₄H₁₀ClF₂NO	D_x = 1.523 Mg m⁻³
M_r = 281.68	Cu Kα radiation, λ = 1.5418 Å
Orthorhombic, P2₁2₁2₁	Cell parameters from 2751 reflections
a = 4.8935 (5) Å	θ = 4.2–71.8°
b = 5.8995 (6) Å	µ = 2.92 mm⁻¹
c = 42.572 (4) Å	T = 173 K
V = 1229.0 (2) Å³	Block, colourless
Z = 4	0.36 × 0.18 × 0.08 mm
F(000) = 576

Data collection top

Agilent Xcalibur (Eos, Gemini) diffractometer	2358 independent reflections
Radiation source: Enhance (Cu) X-ray Source	2293 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.036
Detector resolution: 16.1500 pixels mm^-1	θ_max = 71.9°, θ_min = 4.2°
ω scans	h = −5→5
Absorption correction: multi-scan (CrysAlis PRO and CrysAlis RED; Agilent, 2012)	k = −5→7
T_min = 0.608, T_max = 1.000	l = −51→52
7056 measured reflections

Refinement top

Refinement on F²	Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: full	H-atom parameters constrained
R[F² > 2σ(F²)] = 0.042	w = 1/[σ²(F_o²) + (0.0565P)² + 0.5753P] where P = (F_o² + 2F_c²)/3
wR(F²) = 0.111	(Δ/σ)_max = 0.001
S = 1.14	Δρ_max = 0.42 e Å⁻³
2358 reflections	Δρ_min = −0.28 e Å⁻³
172 parameters	Absolute structure: Flack x determined using 852 quotients [(I+)-(I-)]/[(I+)+(I-)] (Parsons & Flack, 2004).
0 restraints	Absolute structure parameter: −0.003 (14)
Primary atom site location: structure-invariant direct methods

Crystal data top

C₁₄H₁₀ClF₂NO	V = 1229.0 (2) Å³
M_r = 281.68	Z = 4
Orthorhombic, P2₁2₁2₁	Cu Kα radiation
a = 4.8935 (5) Å	µ = 2.92 mm⁻¹
b = 5.8995 (6) Å	T = 173 K
c = 42.572 (4) Å	0.36 × 0.18 × 0.08 mm

Data collection top

Agilent Xcalibur (Eos, Gemini) diffractometer	2358 independent reflections
Absorption correction: multi-scan (CrysAlis PRO and CrysAlis RED; Agilent, 2012)	2293 reflections with I > 2σ(I)
T_min = 0.608, T_max = 1.000	R_int = 0.036
7056 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.042	H-atom parameters constrained
wR(F²) = 0.111	Δρ_max = 0.42 e Å⁻³
S = 1.14	Δρ_min = −0.28 e Å⁻³
2358 reflections	Absolute structure: Flack x determined using 852 quotients [(I+)-(I-)]/[(I+)+(I-)] (Parsons & Flack, 2004).
172 parameters	Absolute structure parameter: −0.003 (14)
0 restraints

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.

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

	x	y	z	U_iso*/U_eq
Cl1	0.07824 (18)	1.15259 (14)	0.52637 (2)	0.0318 (2)
F1	1.2311 (7)	−0.3034 (4)	0.69693 (6)	0.0598 (8)
F2	0.8308 (7)	−0.2387 (5)	0.73854 (6)	0.0667 (9)
O1	0.5599 (5)	0.4621 (4)	0.62977 (6)	0.0325 (6)
N1	0.9971 (6)	0.3740 (5)	0.64241 (6)	0.0278 (6)
H1	1.1690	0.4034	0.6379	0.033*
C1	0.8043 (7)	0.4794 (5)	0.62509 (7)	0.0235 (7)
C2	0.9212 (8)	0.6146 (6)	0.59751 (8)	0.0302 (7)
H2A	1.0618	0.7206	0.6055	0.036*
H2B	1.0118	0.5088	0.5828	0.036*
C3	0.7068 (7)	0.7477 (6)	0.57993 (7)	0.0256 (7)
C4	0.6153 (8)	0.9550 (6)	0.59132 (8)	0.0280 (7)
H4	0.6866	1.0118	0.6105	0.034*
C5	0.4220 (8)	1.0801 (5)	0.57515 (7)	0.0274 (7)
H5	0.3605	1.2217	0.5831	0.033*
C6	0.3201 (7)	0.9951 (6)	0.54724 (7)	0.0242 (7)
C7	0.4066 (8)	0.7886 (6)	0.53548 (7)	0.0276 (7)
H7	0.3341	0.7315	0.5164	0.033*
C8	0.5996 (7)	0.6671 (6)	0.55194 (7)	0.0281 (7)
H8	0.6604	0.5254	0.5440	0.034*
C9	0.9458 (7)	0.2196 (6)	0.66731 (7)	0.0268 (7)
C10	1.1106 (8)	0.0296 (6)	0.66937 (8)	0.0332 (8)
H10	1.2496	0.0031	0.6542	0.040*
C11	1.0702 (9)	−0.1211 (6)	0.69379 (9)	0.0388 (9)
C12	0.8660 (9)	−0.0846 (7)	0.71526 (9)	0.0414 (10)
C13	0.7041 (9)	0.1022 (8)	0.71351 (8)	0.0420 (10)
H13	0.5651	0.1263	0.7287	0.050*
C14	0.7420 (7)	0.2572 (7)	0.68951 (8)	0.0328 (8)
H14	0.6298	0.3882	0.6882	0.039*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Cl1	0.0302 (4)	0.0333 (4)	0.0318 (4)	0.0079 (4)	−0.0016 (3)	0.0064 (3)
F1	0.071 (2)	0.0458 (15)	0.0624 (16)	0.0100 (14)	−0.0095 (14)	0.0118 (13)
F2	0.0690 (19)	0.079 (2)	0.0520 (14)	−0.0119 (17)	−0.0029 (13)	0.0405 (14)
O1	0.0169 (13)	0.0455 (14)	0.0351 (12)	−0.0013 (12)	0.0013 (10)	0.0068 (11)
N1	0.0156 (14)	0.0387 (16)	0.0292 (13)	−0.0024 (11)	0.0008 (10)	0.0070 (12)
C1	0.0190 (17)	0.0247 (16)	0.0267 (15)	−0.0005 (13)	0.0014 (12)	−0.0011 (12)
C2	0.0221 (17)	0.0332 (17)	0.0355 (17)	−0.0003 (17)	0.0047 (14)	0.0104 (14)
C3	0.0216 (16)	0.0264 (16)	0.0288 (16)	−0.0002 (14)	0.0052 (13)	0.0072 (13)
C4	0.0282 (19)	0.0296 (16)	0.0263 (15)	−0.0030 (15)	−0.0021 (13)	−0.0010 (13)
C5	0.0298 (18)	0.0225 (15)	0.0298 (15)	0.0022 (15)	0.0040 (14)	−0.0023 (12)
C6	0.0192 (16)	0.0259 (16)	0.0275 (15)	0.0004 (13)	0.0019 (12)	0.0065 (12)
C7	0.0285 (18)	0.0285 (16)	0.0259 (14)	0.0003 (15)	0.0006 (13)	−0.0021 (12)
C8	0.0290 (18)	0.0249 (15)	0.0303 (15)	0.0063 (15)	0.0045 (14)	−0.0014 (12)
C9	0.0210 (16)	0.0343 (18)	0.0251 (14)	−0.0050 (15)	−0.0043 (13)	0.0024 (12)
C10	0.029 (2)	0.0396 (19)	0.0315 (16)	−0.0003 (16)	−0.0016 (14)	0.0014 (14)
C11	0.039 (2)	0.0347 (19)	0.0425 (19)	−0.0027 (19)	−0.0121 (18)	0.0079 (16)
C12	0.036 (2)	0.053 (2)	0.0352 (18)	−0.0142 (18)	−0.0074 (16)	0.0164 (18)
C13	0.033 (2)	0.065 (3)	0.0282 (17)	−0.007 (2)	0.0036 (15)	0.0057 (18)
C14	0.0234 (19)	0.045 (2)	0.0301 (17)	0.0004 (16)	0.0002 (13)	0.0005 (16)

Geometric parameters (Å, º) top

Cl1—C6	1.747 (3)	C5—H5	0.9500
F1—C11	1.339 (5)	C5—C6	1.383 (5)
F2—C12	1.356 (4)	C6—C7	1.383 (5)
O1—C1	1.217 (4)	C7—H7	0.9500
N1—H1	0.8800	C7—C8	1.377 (5)
N1—C1	1.349 (4)	C8—H8	0.9500
N1—C9	1.420 (4)	C9—C10	1.384 (5)
C1—C2	1.530 (4)	C9—C14	1.392 (5)
C2—H2A	0.9900	C10—H10	0.9500
C2—H2B	0.9900	C10—C11	1.382 (5)
C2—C3	1.509 (5)	C11—C12	1.371 (6)
C3—C4	1.390 (5)	C12—C13	1.359 (6)
C3—C8	1.386 (5)	C13—H13	0.9500
C4—H4	0.9500	C13—C14	1.383 (5)
C4—C5	1.383 (5)	C14—H14	0.9500

C1—N1—H1	117.3	C6—C7—H7	120.5
C1—N1—C9	125.5 (3)	C8—C7—C6	118.9 (3)
C9—N1—H1	117.3	C8—C7—H7	120.5
O1—C1—N1	124.0 (3)	C3—C8—H8	119.4
O1—C1—C2	122.5 (3)	C7—C8—C3	121.2 (3)
N1—C1—C2	113.5 (3)	C7—C8—H8	119.4
C1—C2—H2A	109.0	C10—C9—N1	117.7 (3)
C1—C2—H2B	109.0	C10—C9—C14	120.2 (3)
H2A—C2—H2B	107.8	C14—C9—N1	122.1 (3)
C3—C2—C1	113.1 (3)	C9—C10—H10	120.5
C3—C2—H2A	109.0	C11—C10—C9	119.0 (4)
C3—C2—H2B	109.0	C11—C10—H10	120.5
C4—C3—C2	120.6 (3)	F1—C11—C10	120.5 (4)
C8—C3—C2	120.7 (3)	F1—C11—C12	119.2 (3)
C8—C3—C4	118.7 (3)	C12—C11—C10	120.3 (4)
C3—C4—H4	119.5	F2—C12—C11	118.3 (4)
C5—C4—C3	121.1 (3)	F2—C12—C13	120.6 (4)
C5—C4—H4	119.5	C13—C12—C11	121.0 (3)
C4—C5—H5	120.6	C12—C13—H13	120.1
C4—C5—C6	118.7 (3)	C12—C13—C14	119.9 (4)
C6—C5—H5	120.6	C14—C13—H13	120.1
C5—C6—Cl1	119.2 (3)	C9—C14—H14	120.3
C5—C6—C7	121.3 (3)	C13—C14—C9	119.5 (4)
C7—C6—Cl1	119.4 (3)	C13—C14—H14	120.3

Cl1—C6—C7—C8	179.3 (3)	C4—C5—C6—Cl1	−179.4 (3)
F1—C11—C12—F2	−1.6 (6)	C4—C5—C6—C7	0.3 (5)
F1—C11—C12—C13	177.8 (4)	C5—C6—C7—C8	−0.5 (5)
F2—C12—C13—C14	−179.7 (4)	C6—C7—C8—C3	0.2 (5)
O1—C1—C2—C3	8.0 (5)	C8—C3—C4—C5	−0.3 (5)
N1—C1—C2—C3	−175.1 (3)	C9—N1—C1—O1	3.5 (6)
N1—C9—C10—C11	178.5 (3)	C9—N1—C1—C2	−173.4 (3)
N1—C9—C14—C13	−179.1 (3)	C9—C10—C11—F1	−178.2 (3)
C1—N1—C9—C10	139.2 (4)	C9—C10—C11—C12	1.3 (6)
C1—N1—C9—C14	−42.1 (5)	C10—C9—C14—C13	−0.5 (5)
C1—C2—C3—C4	80.6 (4)	C10—C11—C12—F2	178.9 (4)
C1—C2—C3—C8	−100.1 (4)	C10—C11—C12—C13	−1.6 (6)
C2—C3—C4—C5	179.0 (3)	C11—C12—C13—C14	0.9 (6)
C2—C3—C8—C7	−179.1 (3)	C12—C13—C14—C9	0.2 (6)
C3—C4—C5—C6	0.0 (5)	C14—C9—C10—C11	−0.2 (5)
C4—C3—C8—C7	0.2 (5)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···O1ⁱ	0.88	1.97	2.854 (4)	177
C5—H5···O1ⁱⁱ	0.95	2.63	3.307 (4)	129
C14—H14···F1ⁱⁱⁱ	0.95	2.69	3.615 (5)	164

Symmetry codes: (i) x+1, y, z; (ii) x, y+1, z; (iii) x−1, y+1, z.

Experimental details

Crystal data
Chemical formula	C₁₄H₁₀ClF₂NO
M_r	281.68
Crystal system, space group	Orthorhombic, P2₁2₁2₁
Temperature (K)	173
a, b, c (Å)	4.8935 (5), 5.8995 (6), 42.572 (4)
V (Å³)	1229.0 (2)
Z	4
Radiation type	Cu Kα
µ (mm⁻¹)	2.92
Crystal size (mm)	0.36 × 0.18 × 0.08

Data collection
Diffractometer	Agilent Xcalibur (Eos, Gemini) diffractometer
Absorption correction	Multi-scan (CrysAlis PRO and CrysAlis RED; Agilent, 2012)
T_min, T_max	0.608, 1.000
No. of measured, independent and observed [I > 2σ(I)] reflections	7056, 2358, 2293
R_int	0.036
(sin θ/λ)_max (Å⁻¹)	0.617

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.042, 0.111, 1.14
No. of reflections	2358
No. of parameters	172
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.42, −0.28
Absolute structure	Flack x determined using 852 quotients [(I+)-(I-)]/[(I+)+(I-)] (Parsons & Flack, 2004).
Absolute structure parameter	−0.003 (14)

Computer programs: CrysAlis PRO (Agilent, 2012), SHELXS97 (Sheldrick, 2008), SHELXL2012 (Sheldrick, 2008), OLEX2 (Dolomanov et al., 2009).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···O1ⁱ	0.88	1.97	2.854 (4)	177.1
C5—H5···O1ⁱⁱ	0.95	2.63	3.307 (4)	128.7
C14—H14···F1ⁱⁱⁱ	0.95	2.69	3.615 (5)	163.8

Symmetry codes: (i) x+1, y, z; (ii) x, y+1, z; (iii) x−1, y+1, z.

Acknowledgements

ASP thanks the University of Mysore for research facilities. BN thanks the UGC for financial assistance through a BSR one-time grant for the purchase of chemicals. JPJ acknowledges the NSF–MRI program (grant No. CHE-1039027) for funds to purchase the X-ray diffractometer.

References

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