The β-form of trans-3-(2-nitro­phen­yl)prop-2-enoic acid at 130 K

The crystal structure of a non-centrosymmetric polymorphic modification of the title compound, C₉H₇NO₄, determined at 130 K, shows the presence of 2₁ screw-generated one-dimensional zigzag chains formed through catemeric C(4) syn–anti carboxylic acid hydrogen-bonding associations.

Key indicators

• Single-crystal X-ray study
• T = 130 K
• Mean [sigma](C-C) = 0.009 Å
• R factor = 0.063
• wR factor = 0.111
• Data-to-parameter ratio = 6.4

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT089_ALERT_3_C Poor Data / Parameter Ratio (Zmax .LT. 18) .....       6.38
PLAT241_ALERT_2_C Check High      Ueq as Compared to Neighbors for         C7
PLAT250_ALERT_2_C Large U3/U1 Ratio for Average U(i,j) Tensor ....       2.34
PLAT340_ALERT_3_C Low Bond Precision on C-C bonds (x 1000) Ang ...          9

Alert level G
REFLT03_ALERT_4_G Please check that the estimate of the number of Friedel pairs is
            correct. If it is not, please give the correct count in the
            _publ_section_exptl_refinement section of the submitted CIF.
           From the CIF: _diffrn_reflns_theta_max           25.00
           From the CIF: _reflns_number_total                810
           Count of symmetry unique reflns          810
           Completeness (_total/calc)            100.00%
           TEST3: Check Friedels for noncentro structure
           Estimate of Friedel pairs measured         0
           Fraction of Friedel pairs measured     0.000
           Are heavy atom types Z>Si present         no

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   4 ALERT level C = Check and explain
   1 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
   2 ALERT type 3 Indicator that the structure quality may be low
   1 ALERT type 4 Improvement, methodology, query or suggestion

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Computing details

Data collection: SMART (Bruker, 2000); cell refinement: SMART; data reduction: SAINT (Bruker, 1999); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997) in WinGX (Farrugia, 1999); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997) in WinGX (Farrugia, 1999); molecular graphics: PLATON (Spek, 2003); software used to prepare material for publication: PLATON.

trans-3-(2-nitrophenyl)prop-2-enoic acid

Crystal data

C9H7NO4	F(000) = 200
Mr = 193.16	Dx = 1.537 Mg m^−3
Monoclinic, P21	Melting point: 513 K
Hall symbol: P 2yb	Mo Kα radiation, λ = 0.71073 Å
a = 3.6850 (18) Å	Cell parameters from 219 reflections
b = 7.074 (4) Å	θ = 2.5–16.7°
c = 16.073 (8) Å	µ = 0.12 mm^−1
β = 94.978 (11)°	T = 130 K
V = 417.4 (4) Å^3	Plate, yellow
Z = 2	0.30 × 0.20 × 0.03 mm

Data collection

Bruker SMART CCD area-detector diffractometer	578 reflections with I > 2σ(I
Radiation source: sealed tube	Rint = 0.096
Graphite monochromator	θmax = 25.0°, θmin = 1.3°
φ and ω scans	h = −4→2
2152 measured reflections	k = −8→8
810 independent reflections	l = −19→17

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)] = 0.063	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.111	H-atom parameters constrained
S = 0.81	w = 1/[σ^2(Fo^2) + (0.0161P)^2] where P = (Fo^2 + 2Fc^2)/3
810 reflections	(Δ/σ)max < 0.001
127 parameters	Δρmax = 0.21 e Å^−3
1 restraint	Δρmin = −0.23 e Å^−3

Special details

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 (Ų)

	x	y	z	Uiso*/Ueq
O21	1.0466 (11)	0.3100 (5)	0.8391 (2)	0.0398 (16)
O22	0.7878 (12)	0.3815 (5)	0.9506 (3)	0.0537 (19)
O91	0.8097 (14)	0.1389 (6)	0.5897 (3)	0.0576 (18)
O92	0.9943 (14)	0.3380 (6)	0.4917 (3)	0.0563 (19)
N2	0.8583 (13)	0.4136 (6)	0.8786 (3)	0.0351 (19)
C1	0.6333 (18)	0.5951 (9)	0.7522 (4)	0.043 (3)
C2	0.6942 (16)	0.5846 (8)	0.8373 (4)	0.032 (2)
C3	0.6254 (18)	0.7309 (8)	0.8899 (4)	0.038 (3)
C4	0.4812 (18)	0.8990 (9)	0.8554 (5)	0.051 (3)
C5	0.4196 (17)	0.9123 (9)	0.7716 (4)	0.047 (3)
C6	0.4842 (17)	0.7682 (7)	0.7196 (4)	0.042 (3)
C7	0.697 (2)	0.4400 (9)	0.6943 (4)	0.072 (3)
C8	0.803 (3)	0.4654 (9)	0.6161 (5)	0.074 (4)
C9	0.8736 (19)	0.3128 (10)	0.5586 (4)	0.052 (3)
H3	0.67490	0.71810	0.94870	0.0460*
H4	0.42760	1.00190	0.89030	0.0620*
H5	0.32700	1.02770	0.74820	0.0570*
H6	0.42980	0.78250	0.66110	0.0500*
H7	0.66210	0.31420	0.71260	0.0870*
H8	0.83370	0.59150	0.59770	0.0890*
H91	0.87700	0.03600	0.56200	0.0690*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O21	0.039 (3)	0.027 (2)	0.055 (3)	0.009 (2)	0.014 (2)	−0.007 (2)
O22	0.079 (4)	0.047 (3)	0.038 (3)	0.008 (2)	0.022 (3)	0.009 (2)
O91	0.087 (4)	0.025 (2)	0.062 (3)	−0.004 (3)	0.014 (3)	0.001 (3)
O92	0.091 (4)	0.024 (3)	0.052 (3)	−0.001 (3)	−0.004 (3)	0.003 (2)
N2	0.026 (3)	0.035 (3)	0.045 (4)	0.003 (3)	0.008 (3)	0.002 (3)
C1	0.064 (5)	0.027 (4)	0.035 (4)	−0.003 (4)	−0.007 (4)	−0.003 (3)
C2	0.030 (4)	0.025 (3)	0.040 (4)	−0.002 (3)	0.003 (3)	−0.004 (3)
C3	0.042 (5)	0.038 (4)	0.037 (5)	−0.004 (3)	0.014 (3)	0.002 (4)
C4	0.049 (5)	0.032 (4)	0.076 (6)	−0.003 (4)	0.021 (4)	0.001 (4)
C5	0.049 (5)	0.033 (4)	0.061 (5)	−0.002 (4)	0.012 (4)	0.018 (4)
C6	0.054 (5)	0.029 (4)	0.041 (5)	−0.014 (3)	−0.008 (4)	0.012 (4)
C7	0.140 (8)	0.029 (4)	0.058 (5)	−0.016 (4)	0.017 (5)	0.007 (4)
C8	0.147 (9)	0.025 (4)	0.052 (6)	−0.006 (4)	0.018 (5)	0.004 (4)
C9	0.070 (6)	0.028 (4)	0.055 (5)	−0.006 (4)	−0.007 (4)	−0.012 (4)

Geometric parameters (Å, º)

O21—N2	1.224 (6)	C4—C5	1.350 (10)
O22—N2	1.229 (7)	C5—C6	1.352 (9)
O91—C9	1.356 (8)	C7—C8	1.360 (11)
O92—C9	1.212 (8)	C8—C9	1.459 (10)
O91—H91	0.900	C3—H3	0.9500
N2—C2	1.483 (7)	C4—H4	0.9500
C1—C2	1.369 (9)	C5—H5	0.9500
C1—C6	1.423 (8)	C6—H6	0.9500
C1—C7	1.471 (9)	C7—H7	0.9500
C2—C3	1.374 (9)	C8—H8	0.9500
C3—C4	1.397 (9)
C9—O91—H91	119.0	O91—C9—C8	113.0 (6)
O21—N2—C2	118.9 (5)	O92—C9—C8	123.5 (7)
O22—N2—C2	117.4 (5)	O91—C9—O92	123.3 (6)
O21—N2—O22	123.6 (4)	C2—C3—H3	121.00
C2—C1—C7	124.8 (6)	C4—C3—H3	121.00
C6—C1—C7	119.1 (6)	C3—C4—H4	121.00
C2—C1—C6	116.1 (6)	C5—C4—H4	121.00
N2—C2—C1	121.1 (5)	C4—C5—H5	119.00
N2—C2—C3	115.4 (5)	C6—C5—H5	119.00
C1—C2—C3	123.4 (6)	C1—C6—H6	120.00
C2—C3—C4	118.8 (6)	C5—C6—H6	120.00
C3—C4—C5	118.7 (6)	C1—C7—H7	118.00
C4—C5—C6	122.7 (6)	C8—C7—H7	118.00
C1—C6—C5	120.3 (6)	C7—C8—H8	118.00
C1—C7—C8	124.1 (6)	C9—C8—H8	118.00
C7—C8—C9	124.7 (6)
O21—N2—C2—C3	−153.3 (5)	C6—C1—C2—C3	−1.2 (9)
O21—N2—C2—C1	24.0 (8)	C7—C1—C2—N2	4.3 (10)
O22—N2—C2—C1	−154.0 (6)	N2—C2—C3—C4	178.1 (5)
O22—N2—C2—C3	28.7 (7)	C1—C2—C3—C4	0.9 (10)
C6—C1—C2—N2	−178.3 (5)	C2—C3—C4—C5	−0.9 (10)
C7—C1—C2—C3	−178.7 (6)	C3—C4—C5—C6	1.5 (10)
C2—C1—C6—C5	1.7 (9)	C4—C5—C6—C1	−1.9 (10)
C7—C1—C6—C5	179.3 (6)	C1—C7—C8—C9	178.8 (8)
C2—C1—C7—C8	−147.8 (8)	C7—C8—C9—O92	−174.2 (8)
C6—C1—C7—C8	34.8 (11)	C7—C8—C9—O91	2.3 (13)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O91—H91···O92^i	0.90	1.73	2.632 (7)	180
C7—H7···O21	0.95	2.38	2.721 (8)	101
C7—H7···O91	0.95	2.43	2.767 (8)	100
C8—H8···O92^ii	0.95	2.38	3.276 (9)	157

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