organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

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ISSN: 2056-9890

2-Methyl-3-(3-methyl­phen­yl)acrylic acid

aDepartment of Chemistry, Quaid-i-Azam University, Islamabad 45320, Pakistan, and bUniversity of Sargodha, Department of Physics, Sagrodha, Pakistan
*Correspondence e-mail: dmntahir_uos@yahoo.com

(Received 22 June 2008; accepted 27 June 2008; online 5 July 2008)

The crystal structure of the title compound, C11H12O2, consists of dimers which are formed due to inter­molecular O—H⋯O hydrogen bonding. The dimers are linked to each other by C—H⋯O hydrogen bonds, where C—H belongs to the benzene ring and the O atom is of a carbonyl group of an adjoining mol­ecule. There exist two inter­molecular C—H⋯O hydrogen bonds which form five-membered rings. There exist two ππ inter­actions between the benzene rings. The perpendicular distance in these inter­actions are 3.006 and 3.396 Å. There also exist C—H⋯π and C—O⋯π inter­actions.

Related literature

For related literature, see: Bernstein et al. (1995[Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555-1573.]); Liu et al. (1999[Liu, I. M., Chi, T. C., Hsu, F. L., Chen, C. F. & Cheng, J. T. (1999). Planta Med. 65, 712-714.]); Muhammad et al. (2007[Muhammad, N., Zia-ur-Rehman,, Ali, S. & Meetsma, A. (2007). Acta Cryst. E63, o2174-o2175.]); Natella et al. (1999[Natella, F., Nardini, M., Felico, D. M. & Scaccini, C. (1999). J. Agric. Food Chem. 47, 1453-1459.]); Niaz et al. (2008[Niaz, M., Tahir, M. N., Zia-ur-Rehman,, Ali, S. & Khan, I. U. (2008). Acta Cryst. E64, o733.]); Parez-Alvarez et al. (2001[Parez-Alvarez, V., Bobaddilla, R. A. & Muriel, P. (2001). J. Appl. Toxicol. 21, 527-531.]); Wiesner et al. (2001[Wiesner, J., Mitsch, A., Wissner, P., Jomaa, H. & Schlitzer, M. (2001). Bioorg. Med. Chem. Lett. 11, 423-424.]).

[Scheme 1]

Experimental

Crystal data
  • C11H12O2

  • Mr = 176.21

  • Monoclinic, P 21 /c

  • a = 7.4430 (9) Å

  • b = 13.4094 (16) Å

  • c = 10.2746 (12) Å

  • β = 110.745 (4)°

  • V = 959.0 (2) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.08 mm−1

  • T = 296 (2) K

  • 0.26 × 0.18 × 0.15 mm

Data collection
  • Bruker Kappa APEXII CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2005[Bruker (2005). SADABS. Bruker AXS Inc. Madison, Wisconsin, USA.]) Tmin = 0.980, Tmax = 0.986

  • 11342 measured reflections

  • 2820 independent reflections

  • 1075 reflections with I > 2σ(I)

  • Rint = 0.047

Refinement
  • R[F2 > 2σ(F2)] = 0.056

  • wR(F2) = 0.185

  • S = 1.02

  • 2820 reflections

  • 120 parameters

  • H-atom parameters constrained

  • Δρmax = 0.23 e Å−3

  • Δρmin = −0.20 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

Cg is the centroid of the C4–C9 benzene ring.

D—H⋯A D—H H⋯A DA D—H⋯A
O1—H1⋯O2i 0.82 1.83 2.611 (3) 160
C3—H3⋯O1 0.93 2.27 2.703 (3) 108
C8—H8⋯O1ii 0.93 2.59 3.394 (3) 145
C10—H10A⋯O2 0.96 2.31 2.783 (3) 109
C10—H10CCgiii 0.96 2.75 3.610 (3) 149
C1—O2⋯Cgiv 1.25 (1) 3.57 (1) 3.895 (3) 95 (1)
Symmetry codes: (i) -x, -y, -z+1; (ii) [-x+1, y+{\script{1\over 2}}, -z+{\script{1\over 2}}]; (iii) [x, -y+{\script{1\over 2}}, z+{\script{1\over 2}}]; (iv) x-1, y, z.

Data collection: APEX2 (Bruker, 2007[Bruker (2007). APEX2 and SAINT. Bruker AXS Inc. Madison, Wisconsin, USA.]); cell refinement: APEX2; data reduction: SAINT (Bruker, 2007[Bruker (2007). APEX2 and SAINT. Bruker AXS Inc. Madison, Wisconsin, USA.]); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]) and PLATON (Spek, 2003[Spek, A. L. (2003). J. Appl. Cryst. 36, 7-13.]); software used to prepare material for publication: WinGX publication routines (Farrugia, 1999[Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837-838.]) and PLATON.

Supporting information


Comment top

Cinnamic acids and their derivatives have been studied for their pharmacological properties, including hepatoprotactive (Parez-Alvarez et al., 2001), antimalarial (Wiesner et al., 2001), antioxident (Natella et al., 1999) and antihyperglycemic activities (Liu et al., 1999). In continuation of our efforts to synthesize various derivatives of cinamic acids (Niaz et al., 2008) and their complexes, we herein report the structure of the title compound (I).

The crystal structure of 3-(4-bromophenyl)-2-methylacrylic acid (Muhammad et al., 2007) has been reported. The title compound (I) have a similar environment about the carboxylate group but the attachement of methyl instead of Br-atom is at meta-position instead of para-position.

In the crystal structure of the title compound, the C—C bonds are in the range 1.462 (3)–1.500 (3) Å, and CC have a value of 1.339 (3) Å. The resonant C—O bonds have values of 1.250 (3) and 1.271 (3) Å. In the asymmetric unit, there are two interamolecular H-bonds of C—H···O type (Table 2, Fig 1). Due to these H-bonds, two five membered rings (O1/C1/C2/C3/H3···O1) and (O2/C1/C2/C10/H10A···O2) are formed. The intermolecular (O1—H1···O2i [symmetry code: i = -x, -y, -z + 1]) hydrogen bond forces the molecules into centrosymmetric dimers, forming a R22(8) motif (Bernstein et al. 1995). These dimers are linked to each other by the second intermolecular H-bonding, C8—H8···O2ii [symmetry code: ii = -x + 1, y + 1/2, -z + 1/2] as shown in Fig 2. There exist ππ interactions between the centroids (Cg) of benzene (C4—C9) rings of adjacent molecules. The Cg···Cgiii [symmetry code: iii = x, -y + 1/2, z - 1/2] and Cg···Cgiv [symmetry code: iv = x, -y + 1/2, z + 1/2] have a perpendicular distance of 3.006 and 3.396 Å, respectively. There exist also C10—H10C···Cgiv interaction, with a distance of 3.610 (3) Å between C10 and Cgiv. Similarly another π-interaction is present between C1–O2 and Cgv [symmetry code: v = x - 1, y, z] with a distance of 3.895 (3) Å between C1 and Cgv. The detail of these interactions is also included in Table 1.

Related literature top

For related literature, see: Bernstein et al. (1995); Liu et al. (1999); Muhammad et al. (2007); Natella et al. (1999); Niaz et al. (2008); Parez-Alvarez et al. (2001); Wiesner et al. (2001). Cg is the centroid of the C4–C9 benzene ring.

Experimental top

Compound (I) was prepared according to our previously reported method (Muhammad et al., 2007). A mixture of 3-methylbenzaldehyde (10 mmol, 1.18 ml), methylmalonic acid (2.36 g, 20 mmol) and piperidine (20 mmol, 1.98 ml) in pyridine (12.5 ml) solution was heated on a steam-bath for 24 h. The reaction mixture was cooled and added to a mixture of 25 ml of concentrated HCl and 50 g of ice. The precipitate formed in the acidified mixture was filtered off and washed with ice-cold water. The product was recrystallized from ethanol [yield; 90%, m.p. 321 K].

Refinement top

All H-atoms were positioned geometrically, with C—H = 0.93 and 0.96 Å for aromatic and methyl H-atoms, respectively, and O—H = 0.82 Å for hydroxyl O-atom, and constrained to ride on their parent atoms. The thermal parameters of methyl and hydroxyl H-atoms was taken 1.5 times while for all other H-atoms it was taken 1.2 times of the parent atoms.

Computing details top

Data collection: APEX2 (Bruker, 2007); cell refinement: APEX2 (Bruker, 2007); data reduction: SAINT (Bruker, 2007); 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, 1997) and PLATON (Spek, 2003); software used to prepare material for publication: WinGX publication routines (Farrugia, 1999) and PLATON (Spek, 2003)..

Figures top
[Figure 1] Fig. 1. ORTEP drawing of the title compound, with the atom numbering scheme. The thermal ellipsoids are drawn at the 50% probability level. H-atoms are shown by small circles of arbitrary radii. The intramolecular H-bonds are shown by doted lines.
[Figure 2] Fig. 2. The packing figure (PLATON: Spek, 2003) which shows the dimeric nature of the compound and the interlinkages of the dimers.
2-Methyl-3-(3-methylphenyl)acrylic acid top
Crystal data top
C11H12O2F(000) = 376
Mr = 176.21Dx = 1.220 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 2820 reflections
a = 7.4430 (9) Åθ = 2.6–30.2°
b = 13.4094 (16) ŵ = 0.08 mm1
c = 10.2746 (12) ÅT = 296 K
β = 110.745 (4)°Prismatic, colourless
V = 959.0 (2) Å30.26 × 0.18 × 0.15 mm
Z = 4
Data collection top
Bruker KAPPA APEXII CCD
diffractometer
2820 independent reflections
Radiation source: fine-focus sealed tube1075 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.047
Detector resolution: 7.2 pixels mm-1θmax = 30.2°, θmin = 2.6°
ω scansh = 108
Absorption correction: multi-scan
(SADABS; Bruker, 2005)
k = 1813
Tmin = 0.980, Tmax = 0.986l = 1014
11342 measured reflections
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.056H-atom parameters constrained
wR(F2) = 0.185 w = 1/[σ2(Fo2) + (0.0657P)2 + 0.191P]
where P = (Fo2 + 2Fc2)/3
S = 1.02(Δ/σ)max < 0.001
2820 reflectionsΔρmax = 0.24 e Å3
120 parametersΔρmin = 0.20 e Å3
0 restraintsExtinction correction: empirical, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.006 (2)
Crystal data top
C11H12O2V = 959.0 (2) Å3
Mr = 176.21Z = 4
Monoclinic, P21/cMo Kα radiation
a = 7.4430 (9) ŵ = 0.08 mm1
b = 13.4094 (16) ÅT = 296 K
c = 10.2746 (12) Å0.26 × 0.18 × 0.15 mm
β = 110.745 (4)°
Data collection top
Bruker KAPPA APEXII CCD
diffractometer
2820 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2005)
1075 reflections with I > 2σ(I)
Tmin = 0.980, Tmax = 0.986Rint = 0.047
11342 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0560 restraints
wR(F2) = 0.185H-atom parameters constrained
S = 1.02Δρmax = 0.24 e Å3
2820 reflectionsΔρmin = 0.20 e Å3
120 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 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
xyzUiso*/Ueq
O10.1630 (3)0.00578 (12)0.4174 (2)0.0795 (8)
O20.0675 (2)0.12222 (11)0.51106 (18)0.0699 (7)
C10.1639 (3)0.08682 (17)0.4441 (2)0.0515 (8)
C20.2797 (3)0.15393 (16)0.3911 (2)0.0484 (7)
C30.4010 (3)0.11136 (17)0.3377 (2)0.0533 (8)
C40.5340 (3)0.15354 (16)0.2764 (2)0.0497 (8)
C50.6214 (3)0.08770 (17)0.2126 (2)0.0534 (8)
C60.7448 (3)0.11877 (18)0.1461 (2)0.0553 (8)
C70.7829 (4)0.21882 (19)0.1470 (3)0.0637 (9)
C80.7031 (4)0.2856 (2)0.2118 (3)0.0699 (10)
C90.5794 (4)0.25412 (17)0.2757 (3)0.0646 (9)
C100.2492 (3)0.26372 (17)0.4024 (3)0.0658 (10)
C110.8342 (4)0.0464 (2)0.0760 (3)0.0788 (11)
H10.103600.035950.458720.0954*
H30.400460.042030.339920.0639*
H50.596100.019910.214580.0640*
H70.864450.241810.102850.0764*
H80.733050.352990.212440.0838*
H90.525560.300310.318720.0774*
H10A0.154630.274130.444820.0988*
H10B0.205370.292960.311230.0988*
H10C0.368020.294330.458490.0988*
H11A0.791460.019920.085220.1182*
H11B0.971570.049600.118770.1182*
H11C0.797010.063010.020830.1182*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.1052 (15)0.0487 (10)0.1240 (17)0.0062 (9)0.0893 (13)0.0004 (10)
O20.0786 (12)0.0602 (11)0.0958 (13)0.0042 (8)0.0617 (11)0.0100 (9)
C10.0537 (13)0.0479 (13)0.0629 (15)0.0003 (10)0.0330 (12)0.0028 (11)
C20.0460 (12)0.0467 (12)0.0570 (14)0.0032 (10)0.0239 (11)0.0020 (11)
C30.0583 (14)0.0481 (12)0.0634 (15)0.0046 (11)0.0339 (12)0.0003 (12)
C40.0510 (13)0.0508 (12)0.0549 (14)0.0052 (10)0.0282 (12)0.0009 (11)
C50.0525 (14)0.0513 (13)0.0611 (15)0.0035 (10)0.0261 (12)0.0021 (11)
C60.0490 (13)0.0649 (16)0.0589 (15)0.0034 (11)0.0278 (12)0.0047 (12)
C70.0631 (15)0.0742 (17)0.0646 (16)0.0139 (13)0.0358 (14)0.0053 (13)
C80.0812 (19)0.0581 (15)0.0849 (19)0.0194 (13)0.0475 (17)0.0021 (13)
C90.0767 (17)0.0525 (14)0.0804 (18)0.0098 (12)0.0475 (15)0.0045 (13)
C100.0574 (15)0.0538 (15)0.097 (2)0.0010 (11)0.0408 (15)0.0017 (14)
C110.0757 (18)0.088 (2)0.091 (2)0.0014 (15)0.0521 (17)0.0051 (16)
Geometric parameters (Å, º) top
O1—C11.271 (3)C8—C91.373 (4)
O2—C11.250 (3)C3—H30.9300
O1—H10.8200C5—H50.9300
C1—C21.477 (3)C7—H70.9300
C2—C101.500 (3)C8—H80.9300
C2—C31.339 (3)C9—H90.9300
C3—C41.462 (3)C10—H10A0.9600
C4—C91.391 (3)C10—H10B0.9600
C4—C51.391 (3)C10—H10C0.9600
C5—C61.389 (3)C11—H11A0.9600
C6—C71.371 (4)C11—H11B0.9600
C6—C111.498 (4)C11—H11C0.9600
C7—C81.370 (4)
C1—O1—H1109.00C4—C5—H5119.00
O1—C1—O2122.0 (2)C6—C5—H5119.00
O1—C1—C2118.3 (2)C6—C7—H7119.00
O2—C1—C2119.7 (2)C8—C7—H7119.00
C1—C2—C10116.4 (2)C7—C8—H8120.00
C3—C2—C10126.3 (2)C9—C8—H8120.00
C1—C2—C3117.2 (2)C4—C9—H9120.00
C2—C3—C4132.0 (2)C8—C9—H9120.00
C3—C4—C9125.5 (2)C2—C10—H10A109.00
C5—C4—C9117.3 (2)C2—C10—H10B109.00
C3—C4—C5117.3 (2)C2—C10—H10C109.00
C4—C5—C6122.9 (2)H10A—C10—H10B109.00
C5—C6—C11121.8 (2)H10A—C10—H10C109.00
C7—C6—C11120.8 (2)H10B—C10—H10C109.00
C5—C6—C7117.5 (2)C6—C11—H11A109.00
C6—C7—C8121.2 (3)C6—C11—H11B109.00
C7—C8—C9120.7 (2)C6—C11—H11C110.00
C4—C9—C8120.4 (2)H11A—C11—H11B109.00
C2—C3—H3114.00H11A—C11—H11C109.00
C4—C3—H3114.00H11B—C11—H11C109.00
O1—C1—C2—C310.6 (3)C9—C4—C5—C62.0 (3)
O1—C1—C2—C10169.3 (2)C3—C4—C9—C8178.4 (2)
O2—C1—C2—C3170.7 (2)C5—C4—C9—C81.2 (4)
O2—C1—C2—C109.4 (3)C4—C5—C6—C71.3 (3)
C1—C2—C3—C4179.6 (2)C4—C5—C6—C11178.9 (2)
C10—C2—C3—C40.3 (4)C5—C6—C7—C80.4 (4)
C2—C3—C4—C5171.3 (2)C11—C6—C7—C8179.5 (3)
C2—C3—C4—C98.3 (4)C6—C7—C8—C91.2 (4)
C3—C4—C5—C6177.54 (19)C7—C8—C9—C40.4 (4)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1···O2i0.821.832.611 (3)160
C3—H3···O10.932.272.703 (3)108
C8—H8···O1ii0.932.593.394 (3)145
C10—H10A···O20.962.312.783 (3)109
C10—H10C···Cgiii0.96002.753.610 (3)149.00
C1—O2···Cgiv1.25 (1)3.57 (1)3.895 (3)95 (1)
Symmetry codes: (i) x, y, z+1; (ii) x+1, y+1/2, z+1/2; (iii) x, y+1/2, z+1/2; (iv) x1, y, z.

Experimental details

Crystal data
Chemical formulaC11H12O2
Mr176.21
Crystal system, space groupMonoclinic, P21/c
Temperature (K)296
a, b, c (Å)7.4430 (9), 13.4094 (16), 10.2746 (12)
β (°) 110.745 (4)
V3)959.0 (2)
Z4
Radiation typeMo Kα
µ (mm1)0.08
Crystal size (mm)0.26 × 0.18 × 0.15
Data collection
DiffractometerBruker KAPPA APEXII CCD
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2005)
Tmin, Tmax0.980, 0.986
No. of measured, independent and
observed [I > 2σ(I)] reflections
11342, 2820, 1075
Rint0.047
(sin θ/λ)max1)0.707
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.056, 0.185, 1.02
No. of reflections2820
No. of parameters120
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.24, 0.20

Computer programs: APEX2 (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2003), WinGX publication routines (Farrugia, 1999) and PLATON (Spek, 2003)..

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1···O2i0.821.832.611 (3)160
C3—H3···O10.932.272.703 (3)108
C8—H8···O1ii0.932.593.394 (3)145
C10—H10A···O20.962.312.783 (3)109
C10—H10C···Cgiii0.96002.753.610 (3)149.00
C1—O2···Cgiv1.250 (3)3.574 (2)3.895 (3)95.38 (13)
Symmetry codes: (i) x, y, z+1; (ii) x+1, y+1/2, z+1/2; (iii) x, y+1/2, z+1/2; (iv) x1, y, z.
 

Acknowledgements

The authors acknowledge the the Higher Education Commission, Islamabad, Pakistan, for funding the purchase of the diffractometer at GCU, Lahore, and for financial support to NM for PhD studies under the Indigenous Scholarship Scheme.

References

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