Methyl 3-(4-methoxyphenyl)prop-2-enoate

The title mol­ecule, C₁₁H₁₂O₃, is almost planar, with an average deviation of the C and O atoms from the least-squares plane of 0.146 (4) Å. The geometry about the C=C bond is trans. The phenyl ring and –COOCH₃ group are twisted with respect to the double bond by 9.3 (3) and 5.6 (5)°, respectively. The endocyclic angle at the junction of the propenoate group and the phenyl ring is decreased from 120° by 2.6 (2)°, whereas two neighbouring angles around the ring are increased by 2.3 (2) and 0.9 (2)°. This is probably associated with the charge-transfer interaction of the phenyl ring and –COOCH₃ group through the C=C double bond. The mol­ecules are joined together through C—H...O hydrogen bonds between the methoxy and ester groups to form characteristic zigzag chains extended along the c axis.

S1. Comment

The properties and structure of cinnamic acid and its derivatives, together with their donor-acceptor complexes with other organic compounds, have been reported by a number of publications. One of the major reasons for investigations of these compounds is to analyse their intermolecular hydrogen-bonding interactions from the point of view of crystal engineering, i.e. the design of new materials with particular chemical and physical properties (Nakanishi & Sasada, 1978; Bryan & White, 1982; Desiraju & Sarma, 1983; Desiraju et al., 1984; Desiraju & Sharma, 1991). It was found that intermolecular interactions, even weak hydrogen bonds, may play a major role in the self-assembly of molecules in crystals, their specific molecular architecture and their properties. The analysis of intermolecular interactions, their strengths and their specific geometries may reveal structural features which govern the self-assembly of those molecules, which seems to be very important for the design of new materials. It was found that C—H···O hydrogen bonds may organize molecules into different patterns. Five different C—H···O hydrogen-bond patterns in the structures of organic nitro compounds have been studied by Sharma & Desiraju (1994). Recently, zero-, one-, two- and three-dimensional schemes of the same type of hydrogen bonds have been reported for diaryl sulfones (Glidewell et al., 2001). In the light of this work, we have established the structure of the title compound, (I), and our results are presented here. \sch

The molecule of (I) (Fig. 1) is nearly planar. The largest deviations from the least-squares plane are observed for C2 [0.208 (2) Å], C10 [0.252 (4) Å], C11 [0.266 (3) Å] and O2 [0.181 (3) Å], and the average deviation of non-H atoms from the least-squares plane is 0.146 (4) Å. The torsion angles which most significantly deviate from 0 or 180° are C6—C1—C7—C8 and C2—C1—C7—C8 [8.7 (3)°], together with C7—C8—C9—O2 and C7—C8—C9—O1 [5.2 (5)°] (Table 1). This corresponds with the twists of the phenyl ring and –COOCH₃ group with respect to the C8═C7 double bond of 9.3 (3) and 5.6 (5)°, respectively (Fig. 1).

The C1—C2 bond is elongated, whereas the C2—C3 bond is shortened. The C6—C1—C2 angle is significantly diminished from 120°, whereas two neighbouring angles, C5—C6—C1 and C3—C2—C1, are increased by 2.3 (2) and 0.9 (2)°, respectively, from 120°. This is probably associated with the charge-transfer interaction of the phenyl ring and –COOCH₃ group through the C7═C8 double bond (Domenicano et al., 1975a,b). The assymetry of the exocyclic angles at atoms C1 and C4 agrees quite well with the values found in similar structures (Domiano et al., 1979).

The geometry of the methoxy group is governed by the repulsion between the C11 methyl group and the aromatic ring, leading to the enlargement of the O3—C4—C5 angle and the reduction of O3—C4—C3. Similar repulsion between the C10 methyl group and O1, and between O1 and C7—H7, leads to the enlargement of the O1—C9—O2 and O1—C9—C8 angles, respectively. At the same time, the O2—C9—C8 angle is diminished to 111.1 (2)°. Like the methoxy group, the C9—O2—C10 angle is smaller than 120°, resulting in repulsion between two lone pairs on O2 and the neighbouring atoms.

The repulsion between C8—H8 and C2—H2 leads to enlargement of the C8—C7—C1 and C2—C1—C7 angles. The length of C7═C8 is typical for cinnamic acids (Iwamoto et al., 1989; Iwamoto & Kashino, 1990).

The molecules of (I) are joined head-to-tail through the C—H···O hydrogen bond between the methoxy and ester groups (Table 2), forming characteristic zigzag chains along the c axis (Fig. 2). The molecules are piled up along the shortest crystal a axis to form two parallel plane-to-plane stacks, overlapping to form columns. The angle between molecules from neighbouring stacks is 50.4 (1)°.

S2. Experimental

The title compound was obtained from the para-methoxy derivative of cinnamic acid (chemically pure, NPO Bochimreaktiv, Russia) by the literature procedure of Fischer & Speier (1895). Crystals of (I) for single-crystal X-ray diffraction were grown from a methanol solution by slow evaporation.

S3. Refinement

H atoms were treated as riding, with C—H = 0.96 Å and U_iso(H) = 1.2U_eq(C). Are these the correct constraints?

Computing details

Data collection: Kuma Diffraction Software (Kuma, 1996); cell refinement: Kuma Diffraction Software (Kuma, 1996); data reduction: Kuma Diffraction Software (Kuma, 1995); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL/PC (Sheldrick, 1990); software used to prepare material for publication: SHELXL97 (Sheldrick, 1997).

Figures

	Fig. 1. A view of the molecular structure of (I) with the atom-numbering scheme. Displacement ellipsoids are drawn at the 50% probability level and H atoms are shown as small spheres of arbitrary radii.
	Fig. 2. The crystal structure of (I) showing the formation of the zigzag chains [symmetry codes: (i) -x - 1/2, y, z + 1/2; (ii) -x - 1/2, y, z - 1/2].

Methyl 3-(4-methoxyphenyl)propenoate

Crystal data

C11H12O3	Dx = 1.251 Mg m^−3
Mr = 192.21	Mo Kα radiation, λ = 0.71073 Å
Orthorhombic, Pca21	Cell parameters from 44 reflections
a = 6.203 (1) Å	θ = 6–17°
b = 7.259 (1) Å	µ = 0.09 mm^−1
c = 22.657 (5) Å	T = 295 K
V = 1020.2 (3) Å^3	Pillar, colourless
Z = 4	0.6 × 0.6 × 0.5 mm
F(000) = 408

Data collection

Kuma KM-4 diffractometer	Rint = 0.036
Radiation source: fine-focus sealed tube	θmax = 30.1°, θmin = 2.8°
Graphite monochromator	h = −8→8
ω/θ scans	k = 0→9
2911 measured reflections	l = 0→31
1521 independent reflections	2 standard reflections every 50 reflections
1142 reflections with I > 2σ(I)	intensity decay: 1.0%

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.042	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.119	H-atom parameters constrained
S = 1.03	Calculated w = 1/[σ^2(Fo^2) + (0.0719P)^2 + 0.0319P] where P = (Fo^2 + 2Fc^2)/3
1521 reflections	(Δ/σ)max < 0.001
127 parameters	Δρmax = 0.18 e Å^−3
1 restraint	Δρmin = −0.16 e Å^−3

Special details

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 (Ų)

	x	y	z	Uiso*/Ueq
C1	−0.0668 (3)	0.2458 (2)	0.50348 (9)	0.0431 (4)
C2	0.0402 (3)	0.1621 (3)	0.45595 (10)	0.0466 (4)
H2	0.1769	0.1035	0.4624	0.056*
C3	−0.0479 (3)	0.1632 (3)	0.40043 (9)	0.0462 (4)
H3	0.0277	0.1050	0.3685	0.055*
C4	−0.2457 (3)	0.2475 (2)	0.38988 (8)	0.0433 (4)
C5	−0.3555 (3)	0.3301 (3)	0.43624 (9)	0.0474 (4)
H5	−0.4917	0.3893	0.4296	0.057*
C6	−0.2663 (3)	0.3262 (3)	0.49212 (10)	0.0484 (4)
H6	−0.3446	0.3806	0.5242	0.058*
C7	0.0232 (4)	0.2545 (3)	0.56295 (10)	0.0514 (5)
H7	−0.0708	0.2986	0.5935	0.062*
C8	0.2204 (4)	0.2083 (4)	0.57921 (10)	0.0555 (5)
H8	0.3175	0.1571	0.5506	0.067*
C9	0.2935 (4)	0.2336 (3)	0.64031 (11)	0.0609 (6)
C10	0.5926 (7)	0.2157 (6)	0.70424 (17)	0.0968 (11)
H101	0.7431	0.1847	0.7034	0.116*
H102	0.5759	0.3411	0.7168	0.116*
H103	0.5189	0.1356	0.7312	0.116*
C11	−0.5128 (5)	0.3305 (5)	0.31932 (13)	0.0731 (7)
H111	−0.5441	0.3147	0.2781	0.088*
H112	−0.6277	0.2789	0.3424	0.088*
H113	−0.4994	0.4594	0.3280	0.088*
O1	0.1843 (4)	0.2841 (4)	0.68057 (10)	0.1010 (8)
O2	0.5012 (4)	0.1950 (4)	0.64563 (10)	0.0849 (6)
O3	−0.3167 (3)	0.2403 (2)	0.33326 (8)	0.0558 (4)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
C1	0.0481 (9)	0.0401 (9)	0.0411 (9)	−0.0011 (7)	0.0047 (7)	0.0003 (6)
C2	0.0433 (8)	0.0450 (9)	0.0516 (10)	0.0049 (7)	0.0043 (8)	−0.0019 (7)
C3	0.0478 (10)	0.0458 (9)	0.0451 (10)	0.0034 (7)	0.0080 (8)	−0.0035 (7)
C4	0.0444 (8)	0.0430 (8)	0.0425 (9)	−0.0035 (7)	0.0012 (8)	0.0015 (7)
C5	0.0432 (9)	0.0487 (10)	0.0504 (10)	0.0054 (7)	0.0024 (8)	−0.0009 (8)
C6	0.0462 (9)	0.0498 (10)	0.0492 (10)	0.0061 (7)	0.0091 (8)	−0.0050 (7)
C7	0.0561 (11)	0.0553 (12)	0.0429 (11)	0.0036 (8)	0.0048 (8)	−0.0008 (8)
C8	0.0583 (12)	0.0656 (10)	0.0426 (10)	0.0025 (10)	0.0010 (9)	−0.0018 (9)
C9	0.0661 (14)	0.0702 (14)	0.0463 (12)	0.0037 (11)	−0.0040 (10)	−0.0024 (9)
C10	0.094 (2)	0.129 (3)	0.0670 (19)	0.016 (2)	−0.0303 (17)	−0.0189 (19)
C11	0.0621 (13)	0.101 (2)	0.0564 (14)	0.0122 (13)	−0.0104 (11)	−0.0007 (14)
O1	0.0865 (15)	0.169 (2)	0.0480 (11)	0.0227 (15)	0.0013 (10)	−0.0200 (12)
O2	0.0747 (12)	0.1230 (16)	0.0569 (11)	0.0195 (11)	−0.0162 (10)	−0.0228 (11)
O3	0.0568 (8)	0.0668 (9)	0.0439 (8)	0.0049 (7)	−0.0025 (6)	−0.0022 (6)

Geometric parameters (Å, º)

C1—C2	1.403 (3)	C11—O3	1.418 (3)
C1—C6	1.392 (3)	C2—H2	0.9600
C1—C7	1.460 (3)	C3—H3	0.9600
C2—C3	1.372 (3)	C5—H5	0.9600
C3—C4	1.391 (3)	C6—H6	0.9600
C4—C5	1.388 (3)	C7—H7	0.9600
C4—O3	1.357 (2)	C8—H8	0.9600
C5—C6	1.382 (3)	C10—H101	0.9600
C7—C8	1.321 (3)	C10—H102	0.9600
C8—C9	1.468 (3)	C10—H103	0.9600
C9—O1	1.194 (3)	C11—H111	0.9600
C9—O2	1.324 (3)	C11—H112	0.9600
C10—O2	1.452 (4)	C11—H113	0.9600
C2—C1—C7	123.1 (2)	C3—C2—H2	119.6
C2—C3—C4	120.8 (2)	C4—C3—H3	119.7
C3—C2—C1	120.9 (2)	C4—C5—H5	120.4
C4—O3—C11	118.1 (2)	C5—C6—H6	118.9
C5—C4—C3	119.5 (2)	C6—C5—H5	120.4
C5—C6—C1	122.3 (2)	C7—C8—H8	119.4
C6—C1—C2	117.4 (2)	C8—C7—H7	116.5
C6—C1—C7	119.5 (2)	C9—C8—H8	119.4
C6—C5—C4	119.2 (2)	O2—C10—H101	109.8
C7—C8—C9	121.1 (2)	O2—C10—H102	109.1
C8—C7—C1	126.9 (2)	O2—C10—H103	109.5
C9—O2—C10	116.2 (2)	O3—C11—H111	109.5
O1—C9—C8	125.7 (2)	O3—C11—H112	109.6
O1—C9—O2	123.2 (3)	O3—C11—H113	109.3
O2—C9—C8	111.1 (2)	H101—C10—H102	109.5
O3—C4—C3	115.6 (2)	H101—C10—H103	109.5
O3—C4—C5	125.0 (2)	H102—C10—H103	109.5
C1—C2—H2	119.6	H111—C11—H112	109.5
C1—C6—H6	118.9	H111—C11—H113	109.5
C1—C7—H7	116.6	H112—C11—H113	109.5
C2—C3—H3	119.6
C6—C1—C2—C3	1.2 (3)	C6—C1—C7—C8	−170.1 (2)
C7—C1—C2—C3	−177.65 (18)	C2—C1—C7—C8	8.7 (3)
C1—C2—C3—C4	0.0 (3)	C1—C7—C8—C9	176.6 (2)
C2—C3—C4—O3	179.91 (18)	C7—C8—C9—O1	5.2 (5)
C2—C3—C4—C5	−0.5 (3)	C7—C8—C9—O2	−174.0 (2)
O3—C4—C5—C6	179.31 (17)	O1—C9—O2—C10	0.6 (5)
C3—C4—C5—C6	−0.3 (3)	C8—C9—O2—C10	179.8 (3)
C4—C5—C6—C1	1.5 (3)	C5—C4—O3—C11	3.0 (3)
C2—C1—C6—C5	−1.9 (3)	C3—C4—O3—C11	−177.4 (2)
C7—C1—C6—C5	176.91 (19)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
C11—H111···O1^i	0.96	2.39	3.336 (4)	170

Symmetry code: (i) −x−1/2, y, z−1/2.