Ethyl 2-[(4-chloro­phen­yl)hydrazono]-3-oxobutanoate

Fun, H.-K.; Chantrapromma, S.; Padaki, M.; Radhika; Isloor, A.M.

doi:10.1107/S1600536809012951

organic compounds

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ISSN: 2056-9890

Volume 65| Part 5| May 2009| Page o1029

doi:10.1107/S1600536809012951

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Ethyl 2-[(4-chlorophenyl)hydrazono]-3-oxobutanoate

Hoong-Kun Fun,^a ^*‡ Suchada Chantrapromma,^b § Mahesh Padaki,^c Radhika ^c and Arun M. Isloor ^c

^aX-ray Crystallography Unit, School of Physics, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia, ^bCrystal Materials Research Unit, Department of Chemistry, Faculty of Science, Prince of Songkla University, Hat-Yai, Songkhla 90112, Thailand, and ^cDepartment of Chemistry, National Institute of Technology–Karnataka, Surathkal, Mangalore 575 025, India
^*Correspondence e-mail: hkfun@usm.my

(Received 3 April 2009; accepted 6 April 2009; online 10 April 2009)

The molecule of the title oxobutanoate derivative, C₁₂H₁₃ClN₂O₃, is nearly planar; the interplanar angle between the benzene ring and the mean plane through the hydrazono-3-oxobutanoate unit is 2.69 (3)°. An intramolecular N—H⋯O hydrogen bond generates an S(6) ring motif. In the crystal packing, C—H⋯O(3-oxo) interactions link molecules into dimers. The dimers thus formed are linked through C—H⋯O(carboxylate C=O) interactions, leading to the formation of ribbons along the [01 $[\overline 1]$ ] direction, which are stabilized via Cl⋯Cl [3.2916 (3) Å] contacts. The ribbons are stacked via C⋯O contacts [3.2367 (12)–3.3948 (12) Å].

Related literature

For hydrogen-bond motifs, see Bernstein et al. (1995 ). For background to the bioactivity and applications of oxobutanoate derivatives, see: Alpaslan et al. (2005 ); Billington et al. (1979 ); Stancho et al. (2008 ). For the synthesis, see Amir & Agarwal (1997 ). For the stability of the temperature controller used in the data collection, see Cosier & Glazer (1986 ).

Experimental

Crystal data

C₁₂H₁₃ClN₂O₃
M_r = 268.69
Monoclinic, P 2₁ /c
a = 4.0259 (1) Å
b = 17.0892 (4) Å
c = 18.4934 (5) Å
β = 96.802 (1)°
V = 1263.38 (6) Å³
Z = 4
Mo Kα radiation
μ = 0.30 mm⁻¹
T = 100 K
0.77 × 0.13 × 0.06 mm

Data collection

Bruker APEXII CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2005 ) T_min = 0.799, T_max = 0.982
38796 measured reflections
4723 independent reflections
3972 reflections with I > 2σ(I)
R_int = 0.039

Refinement

R[F² > 2σ(F²)] = 0.037
wR(F²) = 0.108
S = 1.06
4723 reflections
165 parameters
H-atom parameters constrained
Δρ_max = 0.53 e Å⁻³
Δρ_min = −0.24 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1⋯O1	0.91	1.87	2.5721 (12)	132
C2—H2A⋯O2ⁱ	0.93	2.45	3.3536 (13)	164
C5—H5A⋯O1ⁱⁱ	0.93	2.53	3.4293 (12)	163
Symmetry codes: (i) $[-x+1, y+{\script{1\over 2}}, -z+{\script{3\over 2}}]$ ; (ii) -x+3, -y+1, -z+2.

Data collection: APEX2 (Bruker, 2005); cell refinement: SAINT (Bruker, 2005); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 ); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009 ).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809012951/tk2415sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809012951/tk2415Isup2.hkl

checkCIF report

Comment top

Derivatives of oxobutanoates are biologically important. 4-Methylthio-2-oxobutanoate was identified in the culture fluids of a range of bacteria, e.g. the yeast Saccharomyces cerevisiae and the fungus Penicillium digitatum (Billington et al., 1979). Some oxobutanoates exhibit cytotoxic properties (Stancho et al., 2008). The crystal structure of ethyl 4-chloro-2-[2-(2-methoxyphenyl)hydrazono]-3-oxobutanoate has been reported (Alpaslan et al., 2005).

The molecule of the title oxobutanoate derivative, (I), is nearly planar which can be readily indicated by the interplanar angle between the benzene ring and the mean plane through the hydrazono-3-oxobutanoate unit (N1–N2/O1–O3/C7–C10) is 2.69 (3)°, and the C10–C7–C8–C9 torsion angle of 2.81 (15)°. The ethyl group is slightly deviated from the mean plane of the molecule with the torsion angle C10–O3–C11–C12 being 170.6 (9)°. Within the molecule, an intramolecular N1—H1···O1 hydrogen bond generates a S(6) ring motif (Bernstein et al., 1995) (Table 1).

In the crystal packing, the C5—H5A···O1 interactions link two molecules into a dimer (Table 1 and Fig. 2). The dimers are linked together through C2—H2A···O2 interactions to form molecular ribbons along the [011] direction; these ribbons are further stabilized by Cl···Cl [3.2916 (3)Å] contacts. These ribbons are stacked, being connected by C···O [3.2367 (12), 3.3716 (14) and 3.3948 (12)Å] contacts.

Related literature top

For hydrogen-bond motifs, see Bernstein et al. (1995). For background to the bioactivity and applications of oxobutanoate derivatives, see, for example: Alpaslan et al. (2005); Billington et al. (1979); Stancho et al. (2008). For the synthesis, see Amir & Agarwal (1997). For the stability of the temperature controller used in the data collection, see Cosier & Glazer (1986).

Experimental top

Compound (I) was prepared as reported in literature (Amir & Agarwal, 1997). 4-Chloroaniline (1.27 g, 10 mmol) was dissolved in dilute hydrochloric acid (11.0 ml) and cooled to 273 K in an ice bath. To this cold solution, sodium nitrite (1.6 g in 5.0 ml water) was added. The temperature of the reaction mixture was not allowed to raise above 323 K. The resulting diazonium salt solution was then filtered into a cooled solution of ethylacetoacetate (1.7 ml) and sodium acetate (3.5 g) in ethanol (50 ml). The resulting yellow solid was filtered, washed with ice-cold water, dried and recrystallized from methanol. The yield was 1.95 g (81%); M.p. 365 K.

Computing details top

Data collection: APEX2 (Bruker, 2005); cell refinement: SAINT (Bruker, 2005); data reduction: SAINT (Bruker, 2005); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures top

	Fig. 1. The structure of (I), showing 50% probability displacement ellipsoids and the atom-numbering scheme. The N—H···O hydrogen bond was drawn as a dashed line.
	Fig. 2. The packing diagram of (I), viewed along in projection the a axis, showing the arrangement of the dimers into molecular ribbons. C—H···O contacts are shown as dashed lines.

Ethyl 2-[(4-chlorophenyl)hydrazono]-3-oxobutanoate top

Crystal data top

C₁₂H₁₃ClN₂O₃	F(000) = 560
M_r = 268.69	D_x = 1.413 Mg m⁻³
Monoclinic, P2₁/c	Melting point: 365 K
Hall symbol: -P 2ybc	Mo Kα radiation, λ = 0.71073 Å
a = 4.0259 (1) Å	Cell parameters from 4723 reflections
b = 17.0892 (4) Å	θ = 1.6–32.9°
c = 18.4934 (5) Å	µ = 0.30 mm⁻¹
β = 96.802 (1)°	T = 100 K
V = 1263.38 (6) Å³	Needle, brown
Z = 4	0.77 × 0.13 × 0.06 mm

Data collection top

Bruker APEXII CCD area-detector diffractometer	4723 independent reflections
Radiation source: sealed tube	3972 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.039
ϕ and ω scans	θ_max = 32.9°, θ_min = 1.6°
Absorption correction: multi-scan (SADABS; Bruker, 2005)	h = −6→6
T_min = 0.799, T_max = 0.982	k = −26→25
38796 measured reflections	l = −28→28

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)] = 0.037	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.108	H-atom parameters constrained
S = 1.06	w = 1/[σ²(F_o²) + (0.0602P)² + 0.255P] where P = (F_o² + 2F_c²)/3
4723 reflections	(Δ/σ)_max = 0.002
165 parameters	Δρ_max = 0.53 e Å⁻³
0 restraints	Δρ_min = −0.24 e Å⁻³

Crystal data top

C₁₂H₁₃ClN₂O₃	V = 1263.38 (6) Å³
M_r = 268.69	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 4.0259 (1) Å	µ = 0.30 mm⁻¹
b = 17.0892 (4) Å	T = 100 K
c = 18.4934 (5) Å	0.77 × 0.13 × 0.06 mm
β = 96.802 (1)°

Data collection top

Bruker APEXII CCD area-detector diffractometer	4723 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2005)	3972 reflections with I > 2σ(I)
T_min = 0.799, T_max = 0.982	R_int = 0.039
38796 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.037	0 restraints
wR(F²) = 0.108	H-atom parameters constrained
S = 1.06	Δρ_max = 0.53 e Å⁻³
4723 reflections	Δρ_min = −0.24 e Å⁻³
165 parameters

Special details top

Experimental. The crystal was placed in the cold stream of an Oxford Cryosystems Cobra open-flow nitrogen cryostat (Cosier & Glazer, 1986) operating at 100.0 (1) K.

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 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 > σ(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
Cl1	1.33403 (7)	0.917736 (14)	0.966487 (14)	0.02331 (8)
O1	1.1283 (2)	0.43897 (5)	0.92388 (4)	0.02458 (17)
O2	0.4082 (2)	0.41534 (4)	0.74203 (5)	0.02490 (17)
O3	0.40449 (18)	0.54627 (4)	0.73206 (4)	0.01834 (15)
N1	1.0478 (2)	0.58595 (5)	0.89744 (5)	0.01680 (16)
H1	1.1461	0.5484	0.9277	0.020*
N2	0.8324 (2)	0.56553 (5)	0.84259 (4)	0.01607 (15)
C1	0.9700 (2)	0.72408 (6)	0.86488 (5)	0.01779 (18)
H1A	0.8269	0.7109	0.8235	0.021*
C2	1.0384 (3)	0.80222 (6)	0.88190 (5)	0.01815 (18)
H2A	0.9413	0.8418	0.8521	0.022*
C3	1.2535 (2)	0.82023 (5)	0.94400 (5)	0.01668 (17)
C4	1.4070 (2)	0.76234 (6)	0.98899 (5)	0.01816 (18)
H4A	1.5530	0.7756	1.0299	0.022*
C5	1.3393 (2)	0.68425 (6)	0.97197 (5)	0.01727 (17)
H5A	1.4408	0.6447	1.0013	0.021*
C6	1.1185 (2)	0.66568 (5)	0.91065 (5)	0.01550 (17)
C7	0.7628 (2)	0.49093 (5)	0.82808 (5)	0.01602 (17)
C8	0.9246 (2)	0.42509 (6)	0.86964 (5)	0.01779 (18)
C9	0.8553 (3)	0.34161 (6)	0.84741 (6)	0.02176 (19)
H9A	0.9875	0.3074	0.8804	0.033*
H9B	0.9116	0.3337	0.7989	0.033*
H9C	0.6223	0.3304	0.8486	0.033*
C10	0.5100 (2)	0.47889 (6)	0.76369 (5)	0.01646 (17)
C11	0.1696 (2)	0.53891 (6)	0.66655 (5)	0.01926 (18)
H11A	−0.0131	0.5044	0.6752	0.023*
H11B	0.2804	0.5174	0.6272	0.023*
C12	0.0397 (3)	0.61975 (7)	0.64728 (6)	0.0245 (2)
H12A	−0.1123	0.6175	0.6032	0.037*
H12B	0.2235	0.6536	0.6403	0.037*
H12C	−0.0749	0.6397	0.6861	0.037*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Cl1	0.03064 (14)	0.01473 (12)	0.02328 (13)	−0.00497 (9)	−0.00211 (9)	−0.00104 (8)
O1	0.0277 (4)	0.0185 (3)	0.0251 (4)	0.0003 (3)	−0.0070 (3)	0.0031 (3)
O2	0.0306 (4)	0.0165 (3)	0.0254 (4)	−0.0037 (3)	−0.0057 (3)	−0.0015 (3)
O3	0.0185 (3)	0.0163 (3)	0.0190 (3)	−0.0001 (2)	−0.0030 (2)	0.0012 (2)
N1	0.0185 (4)	0.0146 (3)	0.0163 (4)	−0.0003 (3)	−0.0018 (3)	0.0001 (3)
N2	0.0163 (3)	0.0162 (3)	0.0156 (3)	−0.0012 (3)	0.0012 (3)	−0.0015 (3)
C1	0.0200 (4)	0.0162 (4)	0.0162 (4)	−0.0009 (3)	−0.0022 (3)	0.0005 (3)
C2	0.0203 (4)	0.0157 (4)	0.0176 (4)	−0.0005 (3)	−0.0011 (3)	0.0010 (3)
C3	0.0191 (4)	0.0137 (4)	0.0170 (4)	−0.0018 (3)	0.0014 (3)	−0.0006 (3)
C4	0.0187 (4)	0.0179 (4)	0.0169 (4)	−0.0016 (3)	−0.0023 (3)	0.0007 (3)
C5	0.0178 (4)	0.0163 (4)	0.0169 (4)	0.0000 (3)	−0.0014 (3)	0.0011 (3)
C6	0.0163 (4)	0.0135 (4)	0.0165 (4)	−0.0005 (3)	0.0012 (3)	−0.0003 (3)
C7	0.0168 (4)	0.0147 (4)	0.0162 (4)	−0.0008 (3)	0.0002 (3)	0.0008 (3)
C8	0.0189 (4)	0.0155 (4)	0.0189 (4)	−0.0003 (3)	0.0019 (3)	0.0015 (3)
C9	0.0250 (5)	0.0149 (4)	0.0248 (5)	0.0003 (4)	0.0001 (4)	0.0017 (3)
C10	0.0170 (4)	0.0162 (4)	0.0160 (4)	−0.0005 (3)	0.0015 (3)	0.0001 (3)
C11	0.0186 (4)	0.0216 (4)	0.0169 (4)	0.0008 (3)	−0.0012 (3)	0.0006 (3)
C12	0.0238 (5)	0.0235 (5)	0.0253 (5)	0.0032 (4)	−0.0016 (4)	0.0039 (4)

Geometric parameters (Å, º) top

Cl1—C3	1.7386 (9)	C4—H4A	0.9300
O1—C8	1.2412 (12)	C5—C6	1.3924 (13)
O2—C10	1.2121 (12)	C5—H5A	0.9300
O3—C10	1.3378 (12)	C7—C8	1.4703 (13)
O3—C11	1.4514 (11)	C7—C10	1.4864 (13)
N1—N2	1.3018 (11)	C8—C9	1.5017 (14)
N1—C6	1.4072 (12)	C9—H9A	0.9600
N1—H1	0.9104	C9—H9B	0.9600
N2—C7	1.3258 (12)	C9—H9C	0.9600
C1—C2	1.3918 (14)	C11—C12	1.5049 (15)
C1—C6	1.3964 (13)	C11—H11A	0.9700
C1—H1A	0.9300	C11—H11B	0.9700
C2—C3	1.3885 (13)	C12—H12A	0.9600
C2—H2A	0.9300	C12—H12B	0.9600
C3—C4	1.3895 (13)	C12—H12C	0.9600
C4—C5	1.3906 (14)

C10—O3—C11	115.60 (8)	C8—C7—C10	122.13 (8)
N2—N1—C6	119.81 (8)	O1—C8—C7	119.05 (9)
N2—N1—H1	119.4	O1—C8—C9	119.11 (9)
C6—N1—H1	120.7	C7—C8—C9	121.82 (9)
N1—N2—C7	121.37 (8)	C8—C9—H9A	109.5
C2—C1—C6	119.32 (9)	C8—C9—H9B	109.5
C2—C1—H1A	120.3	H9A—C9—H9B	109.5
C6—C1—H1A	120.3	C8—C9—H9C	109.5
C3—C2—C1	119.14 (9)	H9A—C9—H9C	109.5
C3—C2—H2A	120.4	H9B—C9—H9C	109.5
C1—C2—H2A	120.4	O2—C10—O3	123.32 (9)
C2—C3—C4	121.80 (9)	O2—C10—C7	124.16 (9)
C2—C3—Cl1	119.38 (7)	O3—C10—C7	112.52 (8)
C4—C3—Cl1	118.82 (7)	O3—C11—C12	106.97 (8)
C3—C4—C5	119.11 (9)	O3—C11—H11A	110.3
C3—C4—H4A	120.4	C12—C11—H11A	110.3
C5—C4—H4A	120.4	O3—C11—H11B	110.3
C4—C5—C6	119.48 (9)	C12—C11—H11B	110.3
C4—C5—H5A	120.3	H11A—C11—H11B	108.6
C6—C5—H5A	120.3	C11—C12—H12A	109.5
C5—C6—C1	121.12 (9)	C11—C12—H12B	109.5
C5—C6—N1	117.30 (8)	H12A—C12—H12B	109.5
C1—C6—N1	121.57 (8)	C11—C12—H12C	109.5
N2—C7—C8	124.07 (8)	H12A—C12—H12C	109.5
N2—C7—C10	113.78 (8)	H12B—C12—H12C	109.5

C6—N1—N2—C7	179.20 (9)	N1—N2—C7—C8	−2.05 (15)
C6—C1—C2—C3	0.13 (15)	N1—N2—C7—C10	179.71 (9)
C1—C2—C3—C4	1.12 (16)	N2—C7—C8—O1	3.50 (16)
C1—C2—C3—Cl1	−178.83 (8)	C10—C7—C8—O1	−178.40 (10)
C2—C3—C4—C5	−1.00 (15)	N2—C7—C8—C9	−175.28 (10)
Cl1—C3—C4—C5	178.94 (8)	C10—C7—C8—C9	2.81 (15)
C3—C4—C5—C6	−0.36 (15)	C11—O3—C10—O2	−3.29 (14)
C4—C5—C6—C1	1.61 (15)	C11—O3—C10—C7	177.01 (8)
C4—C5—C6—N1	−177.46 (9)	N2—C7—C10—O2	−178.82 (10)
C2—C1—C6—C5	−1.49 (15)	C8—C7—C10—O2	2.90 (16)
C2—C1—C6—N1	177.54 (9)	N2—C7—C10—O3	0.88 (12)
N2—N1—C6—C5	177.14 (9)	C8—C7—C10—O3	−177.40 (9)
N2—N1—C6—C1	−1.93 (15)	C10—O3—C11—C12	170.62 (9)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···O1	0.91	1.87	2.5721 (12)	132
C2—H2A···O2ⁱ	0.93	2.45	3.3536 (13)	164
C5—H5A···O1ⁱⁱ	0.93	2.53	3.4293 (12)	163

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

Experimental details

Crystal data
Chemical formula	C₁₂H₁₃ClN₂O₃
M_r	268.69
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	100
a, b, c (Å)	4.0259 (1), 17.0892 (4), 18.4934 (5)
β (°)	96.802 (1)
V (Å³)	1263.38 (6)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.30
Crystal size (mm)	0.77 × 0.13 × 0.06

Data collection
Diffractometer	Bruker APEXII CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2005)
T_min, T_max	0.799, 0.982
No. of measured, independent and observed [I > 2σ(I)] reflections	38796, 4723, 3972
R_int	0.039
(sin θ/λ)_max (Å⁻¹)	0.764

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.037, 0.108, 1.06
No. of reflections	4723
No. of parameters	165
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.53, −0.24

Computer programs: APEX2 (Bruker, 2005), SAINT (Bruker, 2005), SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···O1	0.91	1.87	2.5721 (12)	132
C2—H2A···O2ⁱ	0.93	2.45	3.3536 (13)	164
C5—H5A···O1ⁱⁱ	0.93	2.53	3.4293 (12)	163

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

Footnotes

‡Thomson Reuters Researcher ID: A-3561-2009.

§Additional correspondence author, e-mail: suchada.c@psu.ac.th. Thomson Reuters Researcher ID: A-5085-2009.

Acknowledgements

AMI is grateful to the Head of the Department of Chemistry and the Director, NITK, Surathkal, India, for providing research facilities. The authors thank the Universiti Sains Malaysia for the Research University Golden Goose grant No. 1001/PFIZIK/811012.

References

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