2-Cyano-3-(4-hydroxy­phenyl)acrylic acid

The title compound, C₁₀H₇NO₃, has an almost planar molecule, forming hydrogen-bonded dimers via the carboxyl groups. These dimers are further connected by hydrogen bonds between the hydroxy groups of the benzene rings and the cyano N atoms into ribbons, which are arranged in layers. The H atom of the carboxyl group is disordered over two sites.

Key indicators

• Single-crystal X-ray study
• T = 173 K
• Mean [sigma](C-C) = 0.001 Å
• R factor = 0.032
• wR factor = 0.093
• Data-to-parameter ratio = 14.2

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT230_ALERT_2_C Hirshfeld Test Diff for    C2     -   C21     ..       6.14 su
PLAT371_ALERT_2_C Long   C(sp2)-C(sp1) Bond  C2     -   C21    ...       1.43 Ang.

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   2 ALERT level C = Check and explain
   0 ALERT level G = General alerts; check

   0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   2 ALERT type 2 Indicator that the structure model may be wrong or deficient
   0 ALERT type 3 Indicator that the structure quality may be low
   0 ALERT type 4 Improvement, methodology, query or suggestion

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Computing details

Data collection: SMART (Siemens, 1995); cell refinement: SMART; data reduction: SAINT (Siemens, 1995); program(s) used to solve structure: SHELXS97 (Sheldrick, 1990); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: PLATON (Spek, 2003) and XP in SHELXTL (Sheldrick, 1991); software used to prepare material for publication: SHELXL97 and PLATON.

2-Cyano-3-(4-hydroxyphenyl)acrylic acid

Crystal data

C10H7NO3	F(000) = 392
Mr = 189.17	Dx = 1.473 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 508 reflections
a = 5.8182 (5) Å	θ = 3.4–20.9°
b = 9.5061 (7) Å	µ = 0.11 mm^−1
c = 15.461 (1) Å	T = 173 K
β = 93.890 (6)°	Block, yellow
V = 853.15 (11) Å^3	0.52 × 0.48 × 0.32 mm
Z = 4

Data collection

Siemens CCD three-circle diffractometer	1798 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.021
Graphite monochromator	θmax = 28.7°, θmin = 2.5°
ω scans	h = −7→7
12012 measured reflections	k = −12→11
1986 independent reflections	l = −20→20

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)] = 0.033	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.093	H atoms treated by a mixture of independent and constrained refinement
S = 1.05	w = 1/[σ^2(Fo^2) + (0.0546P)^2 + 0.1987P] where P = (Fo^2 + 2Fc^2)/3
1986 reflections	(Δ/σ)max = 0.001
140 parameters	Δρmax = 0.33 e Å^−3
0 restraints	Δρmin = −0.20 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	Occ. (<1)
C1	0.36384 (16)	0.34541 (11)	0.40666 (6)	0.0224 (2)
H1	0.2326	0.3778	0.4341	0.027*
C2	0.38596 (16)	0.20353 (10)	0.40581 (6)	0.0212 (2)
C21	0.56447 (16)	0.12633 (10)	0.36770 (6)	0.0220 (2)
N22	0.70468 (16)	0.05833 (9)	0.33942 (6)	0.0282 (2)
C3	0.21527 (16)	0.11533 (11)	0.44786 (6)	0.0215 (2)
O31	0.23948 (13)	−0.01816 (8)	0.43955 (5)	0.0292 (2)
H31	0.145 (4)	−0.064 (3)	0.4640 (16)	0.031 (9)*	0.63 (5)
O32	0.06156 (13)	0.17290 (8)	0.48825 (5)	0.0294 (2)
H32	−0.037 (9)	0.121 (5)	0.507 (3)	0.043 (17)*	0.37 (5)
C11	0.50261 (16)	0.45659 (10)	0.37358 (6)	0.0216 (2)
C12	0.42791 (16)	0.59532 (10)	0.38627 (6)	0.0230 (2)
H12	0.2890	0.6106	0.4138	0.028*
C13	0.55103 (17)	0.70988 (10)	0.35979 (7)	0.0238 (2)
H13	0.4968	0.8028	0.3684	0.029*
C14	0.75632 (16)	0.68712 (10)	0.32025 (6)	0.0222 (2)
O14	0.89012 (13)	0.79352 (8)	0.29448 (5)	0.0301 (2)
H14	0.827 (3)	0.8778 (18)	0.3075 (11)	0.049 (4)*
C15	0.83189 (17)	0.55013 (11)	0.30525 (7)	0.0247 (2)
H15	0.9698	0.5355	0.2769	0.030*
C16	0.70733 (17)	0.43630 (10)	0.33137 (7)	0.0244 (2)
H16	0.7597	0.3436	0.3209	0.029*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
C1	0.0212 (4)	0.0218 (5)	0.0246 (5)	−0.0021 (3)	0.0048 (4)	−0.0006 (4)
C2	0.0211 (4)	0.0200 (5)	0.0230 (5)	−0.0035 (3)	0.0041 (4)	0.0008 (4)
C21	0.0245 (4)	0.0181 (5)	0.0236 (5)	−0.0049 (3)	0.0027 (4)	0.0022 (4)
N22	0.0291 (4)	0.0215 (4)	0.0349 (5)	−0.0015 (3)	0.0089 (4)	0.0010 (4)
C3	0.0218 (4)	0.0196 (5)	0.0234 (5)	−0.0031 (3)	0.0033 (3)	0.0003 (4)
O31	0.0304 (4)	0.0187 (4)	0.0395 (4)	−0.0054 (3)	0.0108 (3)	0.0029 (3)
O32	0.0276 (4)	0.0253 (4)	0.0366 (4)	−0.0067 (3)	0.0131 (3)	−0.0023 (3)
C11	0.0220 (4)	0.0184 (5)	0.0246 (5)	−0.0024 (3)	0.0041 (4)	0.0003 (4)
C12	0.0223 (4)	0.0208 (5)	0.0267 (5)	−0.0002 (4)	0.0063 (4)	−0.0020 (4)
C13	0.0260 (5)	0.0171 (5)	0.0287 (5)	0.0005 (4)	0.0060 (4)	−0.0023 (4)
C14	0.0244 (5)	0.0186 (5)	0.0239 (5)	−0.0043 (3)	0.0045 (4)	0.0001 (4)
O14	0.0331 (4)	0.0186 (4)	0.0403 (4)	−0.0063 (3)	0.0153 (3)	−0.0008 (3)
C15	0.0227 (4)	0.0205 (5)	0.0322 (5)	−0.0010 (4)	0.0101 (4)	−0.0009 (4)
C16	0.0243 (5)	0.0178 (5)	0.0318 (5)	0.0005 (3)	0.0074 (4)	−0.0009 (4)

Geometric parameters (Å, º)

C1—C2	1.3551 (14)	C11—C16	1.4097 (13)
C1—C11	1.4445 (13)	C12—C13	1.3807 (14)
C1—H1	0.9500	C12—H12	0.9500
C2—C21	1.4309 (13)	C13—C14	1.3951 (13)
C2—C3	1.4831 (12)	C13—H13	0.9500
C21—N22	1.1503 (14)	C14—O14	1.3527 (11)
C3—O32	1.2510 (12)	C14—C15	1.3989 (14)
C3—O31	1.2842 (13)	O14—H14	0.910 (17)
O31—H31	0.81 (3)	C15—C16	1.3781 (13)
O32—H32	0.83 (6)	C15—H15	0.9500
C11—C12	1.4065 (13)	C16—H16	0.9500
C2—C1—C11	131.99 (9)	C13—C12—H12	119.1
C2—C1—H1	114.0	C11—C12—H12	119.1
C11—C1—H1	114.0	C12—C13—C14	118.98 (9)
C1—C2—C21	125.92 (9)	C12—C13—H13	120.5
C1—C2—C3	119.44 (9)	C14—C13—H13	120.5
C21—C2—C3	114.64 (8)	O14—C14—C13	122.69 (9)
N22—C21—C2	176.49 (10)	O14—C14—C15	116.97 (8)
O32—C3—O31	124.69 (9)	C13—C14—C15	120.34 (9)
O32—C3—C2	119.62 (9)	C14—O14—H14	110.1 (10)
O31—C3—C2	115.69 (8)	C16—C15—C14	120.33 (9)
C3—O31—H31	113.5 (16)	C16—C15—H15	119.8
C3—O32—H32	117 (3)	C14—C15—H15	119.8
C12—C11—C16	118.14 (9)	C15—C16—C11	120.39 (9)
C12—C11—C1	116.82 (9)	C15—C16—H16	119.8
C16—C11—C1	125.03 (9)	C11—C16—H16	119.8
C13—C12—C11	121.79 (9)
C11—C1—C2—C21	−1.06 (19)	C1—C11—C12—C13	177.92 (9)
C11—C1—C2—C3	178.44 (10)	C11—C12—C13—C14	−0.72 (16)
C1—C2—C3—O32	−4.46 (14)	C12—C13—C14—O14	−178.24 (9)
C21—C2—C3—O32	175.10 (9)	C12—C13—C14—C15	2.04 (16)
C1—C2—C3—O31	175.75 (9)	O14—C14—C15—C16	178.61 (10)
C21—C2—C3—O31	−4.70 (13)	C13—C14—C15—C16	−1.66 (16)
C2—C1—C11—C12	−179.77 (11)	C14—C15—C16—C11	−0.08 (16)
C2—C1—C11—C16	−0.96 (18)	C12—C11—C16—C15	1.37 (16)
C16—C11—C12—C13	−0.97 (16)	C1—C11—C16—C15	−177.43 (10)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O14—H14···N22^i	0.910 (17)	1.934 (17)	2.8435 (12)	177.2 (15)
O31—H31···O32^ii	0.81 (3)	1.79 (3)	2.5967 (10)	176 (2)
O32—H32···O31^ii	0.83 (6)	1.77 (6)	2.5967 (10)	173 (4)

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