2-Methyl-2-(4-nitro­phen­oxy)propanoic acid

Navarrete-Vázquez, G.; Torres-Gómez, H.; Hidalgo-Figueroa, S.; Tlahuext, H.

doi:10.1107/S1600536808035411

organic compounds

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ISSN: 2056-9890

Volume 64| Part 12| December 2008| Page o2261

doi:10.1107/S1600536808035411

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2-Methyl-2-(4-nitrophenoxy)propanoic acid

Gabriel Navarrete-Vázquez,^a Hector Torres-Gómez,^a Sergio Hidalgo-Figueroa ^a and Hugo Tlahuext ^b ^*

^aFacultad de Farmacia, Universidad Autónoma del Estado de Morelos, Av. Universidad 1001 Col Chamilpa CP 62100, Cuernavaca Mor., México, and ^bCentro de Investigaciones Químicas, Universidad Autónoma del Estado de Morelos. Av. Universidad 1001 Col. Chamilpa, CP 62100, Cuernavaca Mor., México
^*Correspondence e-mail: tlahuext@ciq.uaem.mx

(Received 17 October 2008; accepted 29 October 2008; online 8 November 2008)

The title compound, C₁₀H₁₁NO₅, is of interest with respect to its antidyslipidemic activity. It was prepared by reaction of 4-nitrophenol with ethyl 2-bromo-2-methylpropionate followed by ethyl ester hydrolysis. In the crystal, molecules are linked into centrosymmetric dimers by intermolecular O—H⋯O hydrogen bonds and the dimers are connected into chains by weak C—H⋯O interactions. The packing is further stabilized by offset π–π interactions between adjacent benzene rings with a centroid–centroid distance of 3.8643 (17) Å.

Related literature

For related literature on fibrate structures and hypolipidemic activity, see: Navarrete-Vázquez et al. (2008 ); Henry et al. (2003 ); Rath et al. (2005 ); Djinović et al. (1989 ); Thorp (1962 ); Thorp & Waring (1962 ); Miller & Spence (1998 ); Forcheron et al. (2002 ). For details of the graph-set analysis of hydrogen-bonding patterns, see: Bernstein et al. (1995 )

Experimental

Crystal data

C₁₀H₁₁NO₅
M_r = 225.20
Monoclinic, C 2/c
a = 21.296 (3) Å
b = 7.0348 (9) Å
c = 14.518 (2) Å
β = 93.794 (2)°
V = 2170.2 (5) Å³
Z = 8
Mo Kα radiation
μ = 0.11 mm⁻¹
T = 294 (2) K
0.32 × 0.25 × 0.20 mm

Data collection

Bruker SMART APEX CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ) T_min = 0.763, T_max = 0.978
10072 measured reflections
1920 independent reflections
1745 reflections with I > 2σ(I)
R_int = 0.035

Refinement

R[F² > 2σ(F²)] = 0.065
wR(F²) = 0.163
S = 1.12
1920 reflections
152 parameters
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.23 e Å⁻³
Δρ_min = −0.22 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O5—H5A⋯O4ⁱ	0.92 (4)	1.75 (4)	2.659 (3)	173 (3)
C6—H6⋯O1ⁱⁱ	0.93	2.34	3.165 (4)	147
Symmetry codes: (i) $[-x+{\script{1\over 2}}, -y+{\script{3\over 2}}, -z+1]$ ; (ii) x, y+1, z.

Data collection: SMART (Bruker, 2000 ); cell refinement: SAINT-Plus-NT (Bruker, 2001 ); data reduction: SAINT-Plus-NT; program(s) used to solve structure: SHELXTL-NT (Sheldrick, 2008 ); program(s) used to refine structure: SHELXTL-NT; molecular graphics: SHELXTL-NT (Sheldrick, 2008); software used to prepare material for publication: PLATON (Spek, 2003 ) and publCIF (Westrip, 2008 ).

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536808035411/sj2550sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536808035411/sj2550Isup2.hkl

checkCIF report

Comment top

The fibrates belong to a class of lipid-modifying agents that decrease plasma triglycerides (Thorp, 1962; Miller & Spence, 1998; Forcheron et al., 2002). These compounds are used as therapeutic agents in the treatment of dyslipidemia, heart disease and diabetic complications in humans. The fibric acid pharmacophore has been of interest to medicinal chemists ever since the initial discovery that ethyl chlorophenoxyisobutyrate possessed hypolipidemic properties (Thorp & Waring, 1962).

In order to assist our knowledge about the electronic and steric requirements to shown antihyperlipidemic activity, we have determined the crystal structure of the title compound, (I), Fig 1, which is a bioisoster of clofibric acid, with a nitro group instead of chlorine atom. The crystal structure is stabilized by strong O5—H5A···O4 hydrogen-bonding interactions, forming R₂²(8) motifs (Bernstein et al., 1995) (Fig. 1; Table 2). In the crystal packing there are also weak C6—H6···O1 hydrogen bonding interactions that interconnect molecules into chains running along the b axis. The crystal structure is also stabilized by offset π–π interactions between two adjacent molecules, with a distance between centroids of the C1—C6 benzene rings [Cg1, Cg1" (Symmetry code: -x, y, -z + 1/2)] of 3.8643 (17) Å. (Fig. 2; Table 1).

Related literature top

For related literature on fibrate structures and hypolipidemic activity, see: Navarrete-Vázquez et al. (2008); Henry et al. (2003); Rath et al. (2005); Djinović et al. (1989); Thorp (1962); Thorp & Waring (1962); Miller & Spence (1998); Forcheron et al. (2002). For details of the graph-set analysis of hydrogen-bonding patterns, see: Bernstein et al. (1995)

Experimental top

A mixture of 4-nitrophenol (1.0 g, 4.44 mmol), potassium carbonate (1.22 g, 8.88 mmol) in acetonitrile, was added dropwise to 1.04 ml of ethyl 2-bromo-2-methylpropionate (1.29 g, 6.66 mmol). The mixture was stirred and heated under reflux for 8 h then poured onto cold water. The resulting oil was treated with a mixture of THF/MeOH/H₂O (3:2:1), and LiOH (5 equiv) was added. The mixture stirred at room temperature for 3 h, 10% HCl solution added, and most of the organic solvents removed in vacuo. The partly solid residue was extracted with CH₂Cl₂ (3 x 10 ml), dried with Na₂SO₄, filtered, and concentrated in vacuo to give a yellow solid (m.p. 396 K). Single crystals of (I) were obtained from chloroform.

Computing details top

Data collection: SMART (Bruker, 2000); cell refinement: SAINT-Plus-NT (Bruker, 2001); data reduction: SAINT-Plus-NT (Bruker, 2001); program(s) used to solve structure: SHELXTL-NT (Sheldrick, 2008); program(s) used to refine structure: SHELXTL-NT (Sheldrick, 2008); molecular graphics: SHELXTL-NT (Sheldrick, 2008); software used to prepare material for publication: PLATON (Spek, 2003) and publCIF (Westrip, 2008).

Figures top

	Fig. 1. The molecular structure of I showing 50% probability displacement ellipsoids and the atomic numbering. H atoms are shown as small spheres of arbitrary radius.
	Fig. 2. Centrosymmetric dimers generated by O4—H4···O3 intermolecular hydrogen bonds (dotted lines) forming an R₂²(8) motif.
	Fig. 3. View of the offset π-π interaction and C—H···O hydrogen bonds between adjacent molecules. The dashed line indicates the vector between the centroids (Cg1, Cg1"). The hydrogen bond is represented by a dotted line and H atoms not involved in hydrogen bonding have been omitted for clarity.

2-Methyl-2-(4-nitrophenoxy)propanoic acid top

Crystal data top

C₁₀H₁₁NO₅	F(000) = 944
M_r = 225.20	D_x = 1.378 Mg m⁻³
Monoclinic, C2/c	Melting point: 396 K
Hall symbol: -C 2yc	Mo Kα radiation, λ = 0.71073 Å
a = 21.296 (3) Å	Cell parameters from 5496 reflections
b = 7.0348 (9) Å	θ = 2.5–2.9°
c = 14.518 (2) Å	µ = 0.11 mm⁻¹
β = 93.794 (2)°	T = 294 K
V = 2170.2 (5) Å³	Prism, colourless
Z = 8	0.32 × 0.25 × 0.20 mm

Data collection top

Bruker SMART APEX CCD area-detector diffractometer	1920 independent reflections
Radiation source: fine-focus sealed tube	1745 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.035
ϕ and ω scans	θ_max = 25.0°, θ_min = 1.9°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −25→25
T_min = 0.763, T_max = 0.978	k = −8→8
10072 measured reflections	l = −17→17

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)] = 0.065	H atoms treated by a mixture of independent and constrained refinement
wR(F²) = 0.163	w = 1/[σ²(F_o²) + (0.0689P)² + 2.0562P] where P = (F_o² + 2F_c²)/3
S = 1.12	(Δ/σ)_max < 0.001
1920 reflections	Δρ_max = 0.23 e Å⁻³
152 parameters	Δρ_min = −0.22 e Å⁻³
0 restraints	Extinction correction: SHELXTL-NT (Sheldrick, 2008), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.020 (2)

Crystal data top

C₁₀H₁₁NO₅	V = 2170.2 (5) Å³
M_r = 225.20	Z = 8
Monoclinic, C2/c	Mo Kα radiation
a = 21.296 (3) Å	µ = 0.11 mm⁻¹
b = 7.0348 (9) Å	T = 294 K
c = 14.518 (2) Å	0.32 × 0.25 × 0.20 mm
β = 93.794 (2)°

Data collection top

Bruker SMART APEX CCD area-detector diffractometer	1920 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	1745 reflections with I > 2σ(I)
T_min = 0.763, T_max = 0.978	R_int = 0.035
10072 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.065	0 restraints
wR(F²) = 0.163	H atoms treated by a mixture of independent and constrained refinement
S = 1.12	Δρ_max = 0.23 e Å⁻³
1920 reflections	Δρ_min = −0.22 e Å⁻³
152 parameters

Special details top

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
C1	0.43849 (11)	0.9257 (3)	0.38604 (15)	0.0513 (6)
C2	0.42396 (12)	0.7351 (4)	0.3768 (2)	0.0696 (8)
H2	0.3822	0.6954	0.3747	0.084*
C3	0.47162 (13)	0.6040 (4)	0.3706 (2)	0.0783 (9)
H3	0.4623	0.4754	0.3641	0.094*
C4	0.53299 (12)	0.6654 (4)	0.3741 (2)	0.0667 (7)
C5	0.54791 (12)	0.8533 (4)	0.38383 (19)	0.0661 (7)
H5	0.5897	0.8926	0.3866	0.079*
C6	0.50077 (11)	0.9819 (4)	0.38940 (18)	0.0613 (7)
H6	0.5106	1.1103	0.3956	0.074*
C7	0.33120 (11)	1.0562 (4)	0.36820 (17)	0.0584 (7)
C8	0.29840 (10)	0.9120 (3)	0.42697 (16)	0.0532 (6)
C9	0.30573 (14)	1.2523 (4)	0.3905 (2)	0.0801 (9)
H9A	0.3183	1.2844	0.4533	0.120*
H9B	0.2606	1.2512	0.3823	0.120*
H9C	0.3222	1.3448	0.3499	0.120*
C10	0.32173 (14)	1.0132 (5)	0.26611 (19)	0.0772 (8)
H10A	0.3449	1.1033	0.2320	0.116*
H10B	0.2778	1.0221	0.2471	0.116*
H10C	0.3365	0.8871	0.2544	0.116*
H5A	0.2918 (16)	0.838 (5)	0.547 (3)	0.101 (11)*
N1	0.58387 (13)	0.5287 (4)	0.3648 (2)	0.0966 (9)
O1	0.57049 (14)	0.3662 (4)	0.3469 (3)	0.1713 (19)
O2	0.63689 (12)	0.5842 (4)	0.3687 (3)	0.1449 (13)
O3	0.39722 (7)	1.0706 (2)	0.39675 (12)	0.0594 (5)
O4	0.25911 (8)	0.8033 (3)	0.39279 (12)	0.0711 (6)
O5	0.31446 (10)	0.9212 (3)	0.51375 (13)	0.0770 (7)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0472 (12)	0.0552 (14)	0.0519 (13)	−0.0041 (10)	0.0076 (9)	0.0040 (10)
C2	0.0477 (13)	0.0595 (16)	0.103 (2)	−0.0087 (12)	0.0140 (13)	0.0028 (14)
C3	0.0658 (17)	0.0506 (15)	0.121 (2)	−0.0042 (13)	0.0250 (16)	0.0062 (15)
C4	0.0515 (14)	0.0686 (17)	0.0816 (18)	0.0059 (13)	0.0163 (12)	0.0123 (14)
C5	0.0453 (13)	0.0758 (18)	0.0784 (17)	−0.0102 (13)	0.0142 (12)	−0.0012 (14)
C6	0.0536 (14)	0.0583 (14)	0.0736 (16)	−0.0112 (12)	0.0151 (11)	−0.0034 (12)
C7	0.0481 (13)	0.0609 (15)	0.0659 (15)	0.0001 (11)	0.0021 (10)	0.0060 (12)
C8	0.0418 (11)	0.0595 (14)	0.0583 (14)	0.0012 (10)	0.0025 (10)	−0.0016 (11)
C9	0.0691 (17)	0.0653 (17)	0.106 (2)	0.0078 (14)	0.0085 (15)	0.0093 (16)
C10	0.0730 (18)	0.092 (2)	0.0657 (17)	−0.0098 (16)	0.0012 (13)	0.0144 (15)
N1	0.0659 (17)	0.0787 (19)	0.148 (3)	0.0083 (14)	0.0311 (16)	0.0179 (18)
O1	0.105 (2)	0.0664 (17)	0.353 (6)	0.0126 (15)	0.091 (3)	0.017 (2)
O2	0.0574 (15)	0.127 (2)	0.252 (4)	0.0171 (15)	0.0225 (18)	−0.013 (2)
O3	0.0483 (9)	0.0532 (10)	0.0770 (12)	−0.0036 (7)	0.0049 (8)	−0.0015 (8)
O4	0.0619 (11)	0.0864 (14)	0.0648 (11)	−0.0253 (10)	0.0017 (8)	−0.0029 (9)
O5	0.0797 (13)	0.0928 (15)	0.0581 (11)	−0.0337 (11)	0.0008 (9)	0.0035 (10)

Geometric parameters (Å, º) top

C1—O3	1.361 (3)	C7—C8	1.524 (3)
C1—C2	1.380 (4)	C7—C9	1.525 (4)
C1—C6	1.382 (3)	C8—O4	1.215 (3)
C2—C3	1.379 (4)	C8—O5	1.285 (3)
C2—H2	0.9300	C9—H9A	0.9600
C3—C4	1.374 (4)	C9—H9B	0.9600
C3—H3	0.9300	C9—H9C	0.9600
C4—C5	1.365 (4)	C10—H10A	0.9600
C4—N1	1.462 (4)	C10—H10B	0.9600
C5—C6	1.358 (4)	C10—H10C	0.9600
C5—H5	0.9300	N1—O2	1.193 (4)
C6—H6	0.9300	N1—O1	1.202 (4)
C7—O3	1.443 (3)	O5—H5A	0.92 (4)
C7—C10	1.513 (4)

O3—C1—C2	126.6 (2)	C10—C7—C9	111.2 (2)
O3—C1—C6	114.0 (2)	C8—C7—C9	107.5 (2)
C2—C1—C6	119.3 (2)	O4—C8—O5	124.3 (2)
C3—C2—C1	119.6 (2)	O4—C8—C7	121.3 (2)
C3—C2—H2	120.2	O5—C8—C7	114.4 (2)
C1—C2—H2	120.2	C7—C9—H9A	109.5
C4—C3—C2	119.3 (3)	C7—C9—H9B	109.5
C4—C3—H3	120.3	H9A—C9—H9B	109.5
C2—C3—H3	120.3	C7—C9—H9C	109.5
C5—C4—C3	121.5 (2)	H9A—C9—H9C	109.5
C5—C4—N1	118.6 (2)	H9B—C9—H9C	109.5
C3—C4—N1	119.9 (3)	C7—C10—H10A	109.5
C6—C5—C4	118.9 (2)	C7—C10—H10B	109.5
C6—C5—H5	120.5	H10A—C10—H10B	109.5
C4—C5—H5	120.5	C7—C10—H10C	109.5
C5—C6—C1	121.2 (2)	H10A—C10—H10C	109.5
C5—C6—H6	119.4	H10B—C10—H10C	109.5
C1—C6—H6	119.4	O2—N1—O1	122.1 (3)
O3—C7—C10	111.1 (2)	O2—N1—C4	119.0 (3)
O3—C7—C8	111.08 (19)	O1—N1—C4	118.6 (3)
C10—C7—C8	112.3 (2)	C1—O3—C7	122.60 (18)
O3—C7—C9	103.2 (2)	C8—O5—H5A	111 (2)

O3—C1—C2—C3	−177.1 (3)	O3—C7—C8—O5	42.7 (3)
C6—C1—C2—C3	−0.3 (4)	C10—C7—C8—O5	167.7 (2)
C1—C2—C3—C4	0.2 (5)	C9—C7—C8—O5	−69.6 (3)
C2—C3—C4—C5	0.2 (5)	C5—C4—N1—O2	2.2 (5)
C2—C3—C4—N1	−178.2 (3)	C3—C4—N1—O2	−179.4 (4)
C3—C4—C5—C6	−0.6 (4)	C5—C4—N1—O1	−172.6 (4)
N1—C4—C5—C6	177.8 (3)	C3—C4—N1—O1	5.9 (5)
C4—C5—C6—C1	0.5 (4)	C2—C1—O3—C7	−22.5 (4)
O3—C1—C6—C5	177.1 (2)	C6—C1—O3—C7	160.6 (2)
C2—C1—C6—C5	−0.1 (4)	C10—C7—O3—C1	−58.6 (3)
O3—C7—C8—O4	−139.5 (2)	C8—C7—O3—C1	67.2 (3)
C10—C7—C8—O4	−14.5 (3)	C9—C7—O3—C1	−177.9 (2)
C9—C7—C8—O4	108.2 (3)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O5—H5A···O4ⁱ	0.92 (4)	1.75 (4)	2.659 (3)	173 (3)
C6—H6···O1ⁱⁱ	0.93	2.34	3.165 (4)	147

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

Experimental details

Crystal data
Chemical formula	C₁₀H₁₁NO₅
M_r	225.20
Crystal system, space group	Monoclinic, C2/c
Temperature (K)	294
a, b, c (Å)	21.296 (3), 7.0348 (9), 14.518 (2)
β (°)	93.794 (2)
V (Å³)	2170.2 (5)
Z	8
Radiation type	Mo Kα
µ (mm⁻¹)	0.11
Crystal size (mm)	0.32 × 0.25 × 0.20

Data collection
Diffractometer	Bruker SMART APEX CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 1996)
T_min, T_max	0.763, 0.978
No. of measured, independent and observed [I > 2σ(I)] reflections	10072, 1920, 1745
R_int	0.035
(sin θ/λ)_max (Å⁻¹)	0.594

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.065, 0.163, 1.12
No. of reflections	1920
No. of parameters	152
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.23, −0.22

Computer programs: SMART (Bruker, 2000), SAINT-Plus-NT (Bruker, 2001), SHELXTL-NT (Sheldrick, 2008), PLATON (Spek, 2003) and publCIF (Westrip, 2008).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O5—H5A···O4ⁱ	0.92 (4)	1.75 (4)	2.659 (3)	173 (3)
C6—H6···O1ⁱⁱ	0.93	2.34	3.165 (4)	147

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

Acknowledgements

This work was supported by the Consejo Nacional de Ciencia y Tecnología (CONACyT) under grants Nos. 55591 and 3562P-E.

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