Ethyl 5-acetyl-2-amino-4-methyl­thio­phene-3-carboxyl­ate

Akkurt, M.; Yıldırım, S.Ö.; Asiri, A.M.; McKee, V.

doi:10.1107/S1600536808014177

organic compounds

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ISSN: 2056-9890

Volume 64| Part 6| June 2008| Page o1084

doi:10.1107/S1600536808014177

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Ethyl 5-acetyl-2-amino-4-methylthiophene-3-carboxylate

Mehmet Akkurt,^a ^* Sema Öztürk Yıldırım,^a Abdullah Mohamed Asiri ^b and Vickie McKee ^c

^aDepartment of Physics, Faculty of Arts and Sciences, Erciyes University, 38039 Kayseri, Turkey, ^bChemistry Department, Faculty of Science, King Abdul-Aziz University, PO Box 80203, Jeddah 21589, Saudi Arabia, and ^cDepartment of Chemistry, Loughborough University, Leicestershire LE11 3TU, England
^*Correspondence e-mail: akkurt@erciyes.edu.tr

(Received 12 May 2008; accepted 12 May 2008; online 17 May 2008)

In the title compound, C₁₀H₁₃NO₃S, prepared in a one-pot reaction, the molecular conformation is stabilized by an intramolecular N—H⋯O hydrogen bond. The packing is consolidated by further N—H⋯O links. The H atoms of two of the methyl groups are disordered over two sets of sites with equal occupancies.

Related literature

For related literature, see: Gewald et al. (1966 ); Sabnis et al. (1999 ); Akkurt et al. (2008 ); Allen et al. (1987 ).

Experimental

Crystal data

C₁₀H₁₃NO₃S
M_r = 227.28
Monoclinic, P 2₁ /n
a = 7.5397 (3) Å
b = 8.4514 (3) Å
c = 16.7058 (6) Å
β = 94.465 (1)°
V = 1061.28 (7) Å³
Z = 4
Mo Kα radiation
μ = 0.29 mm⁻¹
T = 150 (2) K
0.29 × 0.26 × 0.10 mm

Data collection

Bruker APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 2003 ) T_min = 0.920, T_max = 0.971
12338 measured reflections
3400 independent reflections
2944 reflections with I > 2σ(I)
R_int = 0.025

Refinement

R[F² > 2σ(F²)] = 0.038
wR(F²) = 0.111
S = 1.05
3400 reflections
136 parameters
H-atom parameters constrained
Δρ_max = 0.44 e Å⁻³
Δρ_min = −0.34 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—HN1A⋯O2	0.86	2.15	2.7404 (14)	125
N1—HN1A⋯O2ⁱ	0.86	2.40	3.2077 (15)	156
N1—HN1B⋯O1ⁱⁱ	0.86	2.24	2.9933 (14)	147
C5—H5A⋯O3	0.96	2.04	2.7978 (16)	135
Symmetry codes: (i) -x+2, -y, -z+2; (ii) $[-x+{\script{3\over 2}}, y-{\script{1\over 2}}, -z+{\script{3\over 2}}]$ .

Data collection: APEX2 (Bruker, 2005 ); cell refinement: APEX2; data reduction: APEX2; program(s) used to solve structure: SIR97 (Altomare et al., 1999 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997 ); software used to prepare material for publication: WinGX (Farrugia, 1999 ).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536808014177/hb2733sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536808014177/hb2733Isup2.hkl

checkCIF report

Comment top

2-Aminothiophene derivatives are important intermediates in the synthesis of a variety of agrochemicals, dyes and pharmacologically active compounds (Sabnis et al., 1999). The most convergent and well established classical approach for the preparation of 2-aminothiophenes is Gewald's method (Gewald et al., 1966), which involves the multicomponent condensation of a ketone with an activated nitrile and elemental sulfur in the presence of diethylamine as a catalyst.

As a part of an ongoing investigation into the development of anil derivatives, we here report the structure of the title compound, (I).

All bond lengths and angles in (I) (Fig. 1) are within their normal ranges (Akkurt et al., 2008; Allen et al., 1987). The thiophene ring is almost planar, with a maximum deviation of -0.009 (1) Å for C6. The structure is stabilized by weak intra molecular C—H···O and N—H···O, and intermolecular N—H···O hydrogen bonding interactions (Table 1 and Fig. 2).

Related literature top

For related literature, see: Gewald et al. (1966); Sabnis et al. (1999); Akkurt et al. (2008); Allen et al. (1987).

Experimental top

A mixture of ethyl cyanoacetate (11.3 g, 0.10 mol) and acetyl acetone (10.22 g, 0.10 mol) in absolute ethanol (20 ml) was added to a solution of elemental sulfur (3.2 g, 0.10 mol) and diethylamine (5 ml) in 50 ml absolute ethanol at room temperature. The reaction mixture was refluxed for 3 h and then cooled. The precipitated product was filtered, washed with ethanol, dried and recrystallized from ethanol as orange blocks of (I) [yield: 52%, m.p. 435-437 K]. IR (cm^-1) 3408, 3294 (NH), 1666 (CO), 1605, 1586,1253. ¹H-NMR (CDCl₃): 1.38 (t, 3H, CH3CH₂O),2.43 (s, 3H, COCH₃), 2.7 (s, 3H, CH₃), 4.32 (q, 2H, OCH₂),6.67 (broad s, 2H, NH₂).

Computing details top

Data collection: APEX2 (Bruker, 2005); cell refinement: APEX2 (Bruker, 2005); data reduction: APEX2 (Bruker, 2005); program(s) used to solve structure: SIR97 (Altomare et al., 1999); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures top

	Fig. 1. View of the molecular structure of (I) with displacement ellipsoids for non-H atoms drawn at the 50% probability level. The hydrogen bond is shown as a dashed line.
	Fig. 2. View of the packing and hydrogen bonding in (I).

Ethyl 5-acetyl-2-amino-4-methylthiophene-3-carboxylate top

Crystal data top

C₁₀H₁₃NO₃S	F(000) = 480
M_r = 227.28	D_x = 1.423 Mg m⁻³
Monoclinic, P2₁/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 4913 reflections
a = 7.5397 (3) Å	θ = 2.5–31.1°
b = 8.4514 (3) Å	µ = 0.29 mm⁻¹
c = 16.7058 (6) Å	T = 150 K
β = 94.465 (1)°	Block, orange
V = 1061.28 (7) Å³	0.29 × 0.26 × 0.10 mm
Z = 4

Data collection top

Bruker APEXII CCD diffractometer	3400 independent reflections
Radiation source: sealed tube	2944 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.025
ϕ and ω scans	θ_max = 31.8°, θ_min = 2.5°
Absorption correction: multi-scan (SADABS; Sheldrick, 2003)	h = −11→10
T_min = 0.920, T_max = 0.971	k = −12→12
12338 measured reflections	l = −23→24

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.038	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.111	H-atom parameters constrained
S = 1.05	w = 1/[σ²(F_o²) + (0.06P)² + 0.3751P] where P = (F_o² + 2F_c²)/3
3400 reflections	(Δ/σ)_max = 0.001
136 parameters	Δρ_max = 0.44 e Å⁻³
0 restraints	Δρ_min = −0.34 e Å⁻³

Crystal data top

C₁₀H₁₃NO₃S	V = 1061.28 (7) Å³
M_r = 227.28	Z = 4
Monoclinic, P2₁/n	Mo Kα radiation
a = 7.5397 (3) Å	µ = 0.29 mm⁻¹
b = 8.4514 (3) Å	T = 150 K
c = 16.7058 (6) Å	0.29 × 0.26 × 0.10 mm
β = 94.465 (1)°

Data collection top

Bruker APEXII CCD diffractometer	3400 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 2003)	2944 reflections with I > 2σ(I)
T_min = 0.920, T_max = 0.971	R_int = 0.025
12338 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.038	0 restraints
wR(F²) = 0.111	H-atom parameters constrained
S = 1.05	Δρ_max = 0.44 e Å⁻³
3400 reflections	Δρ_min = −0.34 e Å⁻³
136 parameters

Special details top

Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell e.s.d.'s are taken into account in the estimation of distances, angles and torsion angles

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 (Å²) top

	x	y	z	U_iso*/U_eq	Occ. (<1)
S1	0.74240 (4)	0.44716 (4)	0.82882 (2)	0.0234 (1)
O1	0.58575 (14)	0.74136 (13)	0.79734 (6)	0.0324 (3)
O2	0.94110 (15)	0.13922 (12)	1.03979 (6)	0.0315 (3)
O3	0.83808 (13)	0.32842 (11)	1.11776 (5)	0.0251 (3)
N1	0.88307 (16)	0.17090 (13)	0.87660 (6)	0.0263 (3)
C1	0.5682 (2)	0.86338 (17)	0.92406 (8)	0.0307 (4)
C2	0.61541 (17)	0.72854 (15)	0.87090 (7)	0.0240 (3)
C3	0.69568 (16)	0.58332 (15)	0.90307 (7)	0.0210 (3)
C4	0.74019 (15)	0.52653 (14)	0.97964 (7)	0.0191 (3)
C5	0.71928 (18)	0.61996 (15)	1.05495 (7)	0.0249 (3)
C6	0.81050 (15)	0.36847 (14)	0.97838 (7)	0.0194 (3)
C7	0.82188 (16)	0.31123 (14)	0.89967 (7)	0.0208 (3)
C8	0.87045 (16)	0.26784 (14)	1.04635 (7)	0.0207 (3)
C9	0.90152 (19)	0.23865 (16)	1.18821 (7)	0.0272 (3)
C10	0.8610 (2)	0.33700 (19)	1.25956 (8)	0.0325 (4)
HN1A	0.92190	0.10290	0.91200	0.0320*
H1A	0.51730	0.94800	0.89160	0.0460*	0.500
H1B	0.67360	0.90040	0.95430	0.0460*	0.500
H1C	0.48370	0.82780	0.96020	0.0460*	0.500
H1D	0.59910	0.83610	0.97920	0.0460*	0.500
H1E	0.44280	0.88380	0.91640	0.0460*	0.500
H1F	0.63260	0.95630	0.91050	0.0460*	0.500
HN1B	0.88350	0.14890	0.82640	0.0320*
H5A	0.75800	0.55710	1.10090	0.0370*	0.500
H5B	0.59650	0.64800	1.05770	0.0370*	0.500
H5C	0.78990	0.71440	1.05430	0.0370*	0.500
H5D	0.67160	0.72250	1.04100	0.0370*	0.500
H5E	0.83320	0.63170	1.08430	0.0370*	0.500
H5F	0.63970	0.56530	1.08760	0.0370*	0.500
H9A	1.02850	0.21990	1.18830	0.0330*
H9B	0.84120	0.13740	1.18920	0.0330*
H10A	0.90050	0.28220	1.30800	0.0490*
H10B	0.73510	0.35490	1.25850	0.0490*
H10C	0.92150	0.43670	1.25770	0.0490*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
S1	0.0306 (2)	0.0254 (2)	0.0142 (1)	−0.0032 (1)	0.0017 (1)	−0.0009 (1)
O1	0.0409 (6)	0.0366 (5)	0.0198 (4)	0.0027 (4)	0.0031 (4)	0.0076 (4)
O2	0.0468 (6)	0.0238 (4)	0.0241 (5)	0.0083 (4)	0.0037 (4)	−0.0003 (3)
O3	0.0348 (5)	0.0258 (4)	0.0147 (4)	0.0055 (4)	0.0015 (3)	0.0012 (3)
N1	0.0373 (6)	0.0222 (5)	0.0197 (5)	−0.0009 (4)	0.0038 (4)	−0.0052 (4)
C1	0.0386 (7)	0.0263 (6)	0.0271 (6)	0.0064 (5)	0.0016 (5)	0.0038 (5)
C2	0.0248 (5)	0.0262 (6)	0.0212 (5)	−0.0031 (4)	0.0027 (4)	0.0040 (4)
C3	0.0245 (5)	0.0224 (5)	0.0163 (5)	−0.0032 (4)	0.0023 (4)	−0.0006 (4)
C4	0.0200 (5)	0.0211 (5)	0.0164 (5)	−0.0030 (4)	0.0022 (4)	−0.0010 (4)
C5	0.0327 (6)	0.0246 (6)	0.0174 (5)	0.0024 (5)	0.0017 (4)	−0.0026 (4)
C6	0.0216 (5)	0.0206 (5)	0.0161 (5)	−0.0026 (4)	0.0018 (4)	−0.0013 (4)
C7	0.0228 (5)	0.0217 (5)	0.0180 (5)	−0.0045 (4)	0.0024 (4)	−0.0017 (4)
C8	0.0234 (5)	0.0215 (5)	0.0173 (5)	−0.0025 (4)	0.0019 (4)	−0.0008 (4)
C9	0.0360 (7)	0.0270 (6)	0.0185 (5)	0.0027 (5)	0.0010 (5)	0.0057 (4)
C10	0.0407 (7)	0.0392 (7)	0.0179 (5)	0.0024 (6)	0.0044 (5)	0.0023 (5)

Geometric parameters (Å, º) top

S1—C3	1.7479 (13)	C1—H1A	0.9600
S1—C7	1.7232 (12)	C1—H1B	0.9600
O1—C2	1.2366 (15)	C1—H1C	0.9600
O2—C8	1.2192 (16)	C1—H1D	0.9600
O3—C8	1.3380 (15)	C1—H1E	0.9600
O3—C9	1.4498 (15)	C1—H1F	0.9600
N1—C7	1.3400 (16)	C5—H5A	0.9600
N1—HN1A	0.8600	C5—H5B	0.9600
N1—HN1B	0.8600	C5—H5C	0.9600
C1—C2	1.5044 (19)	C5—H5D	0.9600
C2—C3	1.4529 (18)	C5—H5E	0.9600
C3—C4	1.3829 (17)	C5—H5F	0.9600
C4—C6	1.4379 (17)	C9—H9A	0.9700
C4—C5	1.5040 (17)	C9—H9B	0.9700
C6—C7	1.4100 (17)	C10—H10A	0.9600
C6—C8	1.4619 (17)	C10—H10B	0.9600
C9—C10	1.5039 (19)	C10—H10C	0.9600

C3—S1—C7	91.72 (6)	H1C—C1—H1D	56.00
C8—O3—C9	116.87 (10)	H1C—C1—H1E	56.00
HN1A—N1—HN1B	120.00	H1C—C1—H1F	141.00
C7—N1—HN1A	120.00	H1D—C1—H1E	110.00
C7—N1—HN1B	120.00	H1D—C1—H1F	109.00
O1—C2—C1	119.18 (12)	H1E—C1—H1F	109.00
O1—C2—C3	118.66 (11)	C4—C5—H5A	109.00
C1—C2—C3	122.17 (11)	C4—C5—H5B	110.00
S1—C3—C2	113.26 (9)	C4—C5—H5C	109.00
C2—C3—C4	134.38 (11)	C4—C5—H5D	109.00
S1—C3—C4	112.34 (9)	C4—C5—H5E	109.00
C5—C4—C6	124.25 (10)	C4—C5—H5F	109.00
C3—C4—C6	111.84 (10)	H5A—C5—H5B	109.00
C3—C4—C5	123.91 (11)	H5A—C5—H5C	110.00
C4—C6—C7	112.44 (10)	H5A—C5—H5D	141.00
C4—C6—C8	128.40 (11)	H5A—C5—H5E	56.00
C7—C6—C8	119.16 (10)	H5A—C5—H5F	56.00
N1—C7—C6	128.26 (11)	H5B—C5—H5C	109.00
S1—C7—N1	120.11 (9)	H5B—C5—H5D	56.00
S1—C7—C6	111.64 (9)	H5B—C5—H5E	141.00
O2—C8—O3	122.18 (11)	H5B—C5—H5F	56.00
O2—C8—C6	124.04 (11)	H5C—C5—H5D	56.00
O3—C8—C6	113.77 (10)	H5C—C5—H5E	56.00
O3—C9—C10	106.24 (11)	H5C—C5—H5F	141.00
C2—C1—H1A	109.00	H5D—C5—H5E	109.00
C2—C1—H1B	109.00	H5D—C5—H5F	109.00
C2—C1—H1C	109.00	H5E—C5—H5F	109.00
C2—C1—H1D	109.00	O3—C9—H9A	110.00
C2—C1—H1E	109.00	O3—C9—H9B	110.00
C2—C1—H1F	109.00	C10—C9—H9A	111.00
H1A—C1—H1B	109.00	C10—C9—H9B	110.00
H1A—C1—H1C	109.00	H9A—C9—H9B	109.00
H1A—C1—H1D	141.00	C9—C10—H10A	109.00
H1A—C1—H1E	56.00	C9—C10—H10B	110.00
H1A—C1—H1F	56.00	C9—C10—H10C	109.00
H1B—C1—H1C	110.00	H10A—C10—H10B	109.00
H1B—C1—H1D	56.00	H10A—C10—H10C	110.00
H1B—C1—H1E	141.00	H10B—C10—H10C	109.00
H1B—C1—H1F	56.00

C7—S1—C3—C2	−178.44 (10)	C2—C3—C4—C6	177.16 (13)
C7—S1—C3—C4	0.21 (10)	C3—C4—C6—C7	1.69 (15)
C3—S1—C7—N1	−179.68 (11)	C3—C4—C6—C8	−179.30 (12)
C3—S1—C7—C6	0.76 (10)	C5—C4—C6—C7	−177.67 (11)
C9—O3—C8—O2	3.93 (18)	C5—C4—C6—C8	1.35 (19)
C9—O3—C8—C6	−177.14 (10)	C4—C6—C7—S1	−1.52 (13)
C8—O3—C9—C10	175.85 (11)	C4—C6—C7—N1	178.96 (12)
O1—C2—C3—S1	1.18 (16)	C8—C6—C7—S1	179.36 (9)
O1—C2—C3—C4	−177.07 (13)	C8—C6—C7—N1	−0.2 (2)
C1—C2—C3—S1	−178.56 (10)	C4—C6—C8—O2	−174.17 (12)
C1—C2—C3—C4	3.2 (2)	C4—C6—C8—O3	6.93 (18)
S1—C3—C4—C5	178.25 (10)	C7—C6—C8—O2	4.79 (19)
S1—C3—C4—C6	−1.10 (13)	C7—C6—C8—O3	−174.12 (11)
C2—C3—C4—C5	−3.5 (2)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—HN1A···O2	0.86	2.15	2.7404 (14)	125
N1—HN1A···O2ⁱ	0.86	2.40	3.2077 (15)	156
N1—HN1B···O1ⁱⁱ	0.86	2.24	2.9933 (14)	147
C5—H5A···O3	0.96	2.04	2.7978 (16)	135

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

Experimental details

Crystal data
Chemical formula	C₁₀H₁₃NO₃S
M_r	227.28
Crystal system, space group	Monoclinic, P2₁/n
Temperature (K)	150
a, b, c (Å)	7.5397 (3), 8.4514 (3), 16.7058 (6)
β (°)	94.465 (1)
V (Å³)	1061.28 (7)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.29
Crystal size (mm)	0.29 × 0.26 × 0.10

Data collection
Diffractometer	Bruker APEXII CCD diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 2003)
T_min, T_max	0.920, 0.971
No. of measured, independent and observed [I > 2σ(I)] reflections	12338, 3400, 2944
R_int	0.025
(sin θ/λ)_max (Å⁻¹)	0.742

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.038, 0.111, 1.05
No. of reflections	3400
No. of parameters	136
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.44, −0.34

Computer programs: APEX2 (Bruker, 2005), SIR97 (Altomare et al., 1999), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997), WinGX (Farrugia, 1999).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—HN1A···O2	0.86	2.15	2.7404 (14)	125
N1—HN1A···O2ⁱ	0.86	2.40	3.2077 (15)	156
N1—HN1B···O1ⁱⁱ	0.86	2.24	2.9933 (14)	147
C5—H5A···O3	0.96	2.04	2.7978 (16)	135

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

References

Akkurt, M., Yalçın, Ş. P., Asiri, A. M. & Büyükgüngör, O. (2008). Acta Cryst. E64, o923. Web of Science CSD CrossRef IUCr Journals Google Scholar
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Volume 64| Part 6| June 2008| Page o1084

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