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

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 65| Part 8| August 2009| Pages o2060-o2061
doi:10.1107/S1600536809030141

(E)-2-(2-Nitro­prop-1-en­yl)furan

Pedro Valerga,a* M. Carmen Puerta,a Zenaida Rodríguez Negrín,b Nilo Castañedo Canciob and Miguel Palma Lovilloc

aDepartamento de Ciencia de los Materiales e Ingeniería Metalúrgica, Facultad de Ciencias, Campus Universitario del Río San Pedro, Puerto Real 11510, Spain, bCentro de Bioactivos Químicos, Universidad Central Marta Abreu de Las, Villas, Cuba, and cDepartamento de Química Analítica, Facultad de Ciencias, Campus Universitario del Río San Pedro, Puerto Real 11510, Spain
*Correspondence e-mail: pedro.valerga@uca.es

(Received 25 July 2009; accepted 29 July 2009; online 31 July 2009)

Crystals of the title compound, C7H7NO3, under Mo Kα radiation sublime in less than 1h at room temperature. However, it was possible to collect data at 100K. It crystallized as the E isomer only. A double-bond conjugation in the furan ring is extended to the nitro­alkenyl group. Mol­ecular associations were realized in the crystal through N⋯π [3.545 (2) Å] inter­actions involving the furan ring and C—H⋯O hydrogen bonds.

Related literature

For general background to (nitro-alken­yl)-furan compounds, see: Yan et al. (2008[Yan, S., Gao, Y., Xing, R., Shen, Y., Liu, Y., Wu, P. & Wu, H. (2008). Tetrahedron Lett. 64, 6294-6299.]); Ono N. (2006[Ono, N. (2006). Sci. Synth. 33, 337-370.]); Vallejos et al. (2005[Vallejos, G., Fierro, A., Rezende, M. C., Sepúlveda-Bozab, S. & Reyes-Parada, M. (2005). Bioorg. Med. Chem. 14, 4450-4457.]); Negrín et al. (2003[Negrín, Z. R., Martínez, B. N. H., Meseguer, G. P., Placeres, E. G. & Molina, M. I. D. (2003). Cent. Azúcar, 30, 30-34.]); Negrín et al. (2002[Negrín, Z. R., Placeres, E. G., Martínez, B. N. H., Meseguer, G. P. & Montenegro, O. N. (2002). Cent. Azúcar, 29, 79-86.]), Estrada et al. (1999[Estrada, E., Gomez, M., Castañedo, N. & Perez, C. (1999). J. Mol. Struct. THEOCHEM, 468, 193-200. [Amended journal title OK?].]); Agafonov et al. (1991[Agafonov, N. E., Sedishev, I. P., Dudin, A. V., Kutin, A. A., Stashina, G. A. & Zhulin, V. M. (1991). Izv. Akad. Nauk SSSR Ser. Khim. 2, 426-433.]); Gruntfest et al. (1972[Gruntfest, M. G., Potemkin, G. F., Kolodyazhnyi, Y. V., Zverev, V. V., Nazarova, Z. N. & Osipov, O. A. (1972). Zh. Org. Khim. 8, 404-411.]). For related structures, see: Valerga et al. (2009[Valerga, P., Puerta, M. C., Rodríguez Negrín, Z., Castañedo Cancio, N. & Palma Lovillo, M. (2009). Acta Cryst. E65, o1979.]); Martínez-Bescos et al. (2008[Martínez-Bescos, P., Cagide-Fagin, F., Roa, L. F., Ortiz-Lara, J. C., Kierus, K., Ozores-Viturro, L., Fernández-González, M. & Alonso, R. (2008). J. Org. Chem. 73, 3745-3753.]); Novoa-de-Armas et al. (1997[Novoa-de-Armas, H., Pomes-Hernández, R., Duque-Rodríguez, J. & Toscano, R. A. (1997). Z. Kristallogr. 212, 63-63.]); Pomés et al. (1995[Pomés, R., Duque, J., Novoa, H., Castañedo, N. & Toscano, A. (1995). Acta Cryst. C51, 1368-1369.]).

[Scheme 1]

Experimental

Crystal data

  • C7H7NO3

  • Mr = 153.14

  • Monoclinic, P 21 /n

  • a = 7.1061 (14) Å

  • b = 9.4394 (19) Å

  • c = 10.743 (2) Å

  • β = 101.86 (3)°

  • V = 705.2 (3) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.12 mm−1

  • T = 100 K

  • 0.45 × 0.30 × 0.18 mm
Data collection

  • Bruker SMART APEX diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 2004[Sheldrick, G. M. (2004). SADABS. University of Göttingen, Germany.]) Tmin = 0.898, Tmax = 1.000 (expected range = 0.880–0.980)

  • 5648 measured reflections

  • 1620 independent reflections

  • 1497 reflections with I > 2σ(I)

  • Rint = 0.032
Refinement

  • R[F2 > 2σ(F2)] = 0.049

  • wR(F2) = 0.130

  • S = 1.07

  • 1620 reflections

  • 102 parameters

  • H-atom parameters constrained

  • Δρmax = 0.29 e Å−3

  • Δρmin = −0.34 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A D⋯A D—H⋯A
C2—H2⋯O3i 0.95 2.47 3.3037 (19) 147
C5—H5⋯O3i 0.95 3.03 3.770 (2) 136
C4—H4⋯O2ii 0.95 2.65 3.2980 (19) 126
C4—H4⋯O3ii 0.95 2.58 3.516 (2) 170
C7—H7C⋯O2iii 0.98 2.70 3.310 (2) 121
Symmetry codes: (i) [x+{\script{1\over 2}}, -y+{\script{1\over 2}}, z+{\script{1\over 2}}]; (ii) x, y+1, z; (iii) [x-{\script{1\over 2}}, -y+{\script{1\over 2}}, z-{\script{1\over 2}}].

Data collection: SMART (Bruker, 2001[Bruker (2001). SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2001[Bruker (2001). SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXTL; molecular graphics: ORTEP-3 (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]); software used to prepare material for publication: SHELXTL.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809030141/kp2230sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809030141/kp2230Isup2.hkl

checkCIF report


Comment top

Some (nitro-alkenyl)-furan compounds show antibacterial and antifungal activities and were described and patented as drugs ingredients for veterinarian and agricultural purposes. We recently started the structural study of this group of furylnitroolefins. The title compound crystallized exclusively in its E configuration (Fig. 1). The conjugated system of double bonds in furan ring is extended to the alkenyl group being C2—C3 and C1—C5 bond lenghts 1.422 (2) and 1.431 (2) Å, significatively shorter than single C—C bonds. Distances N1—O2 = 1.232 (2) and N1—O3= 1.231 (2) indicate conjugation with a delocalized double bond. Alkenyl C5 and C6 sp2 carbons are coplanar with the furan ring as shown by an angle of 3.9 (1)° between ring plane and C5 C6 C7 N1 plane. Crystal packing shows N···π interactions involving the furan ring: N···Cg (1/2-x, -1/2+y,1/2-z) distance is 3.545 (2) Å (Fig. 2) and CH···O hydrogen bonds (Table 1).

Related literature top

For general background to the biological activity and applications for veterinary and agricultural products of (nitro-alkenyl)-furan compounds, see: Yan et al. (2008); Ono N. (2006); Vallejos et al. (2005); Negrín et al. (2003); Negrín et al. (2002), Estrada et al. (1999); Agafonov et al. (1991); Gruntfest et al. (1972). For related structures, see: Valerga et al. (2009); Martínez-Bescos et al. (2008); Novoa-de-Armas et al. (1997); Pomés et al. (1995).

Experimental top

2-(2-Nitro-propen-1-yl)-furan, also called UC-244, was obtained using the Knoevenagel's condensation method by reaction of furfural, an aromatic compound from acid hydrolysis of sugar cane residuals (straw, sawdust, etc.) and nitroethane in the presence of isobutylamine as a catalyst. To obtain a product with purity higher than 99% the method was optimized studying temperature, contact and reaction times as variables. The purification was achieved using activated coal and ethanol. The yellow crystals should be protected from the light and heating. 1H NMR (CDCl3) δ (ppm): 2.511 (3H, s, -CH3), 6.533 (1H, dd, 2J = 3.6 Hz and 2J = 1.6 Hz, -O-CH=CH-CH=), 6.781 (1H, d, 2J = 3.6Hz, -O-CH=CH-CH=), 7.599 (1H, d, 2J = 1.6 Hz, -O-CH=CH-CH=), 7.775 (1H, s, HC=CMe) 13C{1H} NMR (CDCl3) δ (ppm): 13.656 (-C H3), 112.688 (-O-CH=CH-CH=), 119.100 (-O-CH=CH-CH=), 120.346 (-C=C(Me)NO2), 144.097 (-C=C(Me)NO2), 146.104 (-O-CH=CH-CH=), 147.679 (Cring-CH-C=C(Me)NO2).

Refinement top

All H atoms were positioned geometrically and treated as riding (C—H = 0.99Å for methylene and C—H = 0.93Å otherwise). Uiso(H) = 1.2 Ueq(C) of the carrier atom. In the absence of any significant anomalous scatters, the Friedel pairs were merged before final refinements.

Computing details top

Data collection: SMART (Bruker, 2001); cell refinement: SAINT (Bruker, 2001); data reduction: SAINT (Bruker, 2001); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. ORTEP representation of I with the atom labelling scheme and displacement ellipsoids at the 50% probability level.
[Figure 2] Fig. 2. Packing diagram of E-2-(2-nitro-propen-1-yl)-furan.
(E)-2-(2-Nitroprop-1-enyl)furan top
Crystal data top
C7H7NO3F(000) = 320
Mr = 153.14Dx = 1.442 Mg m−3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ynCell parameters from 2619 reflections
a = 7.1061 (14) Åθ = 2.9–27.6°
b = 9.4394 (19) ŵ = 0.12 mm−1
c = 10.743 (2) ÅT = 100 K
β = 101.86 (3)°Irregular, yellow
V = 705.2 (3) Å30.45 × 0.30 × 0.18 mm
Z = 4
Data collection top
Bruker SMART APEX
diffractometer		1620 independent reflections
Radiation source: fine-focus sealed tube1497 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.032
1700 ω scan frames, 0.3°, 10sθmax = 27.6°, θmin = 2.9°
Absorption correction: multi-scan
(SADABS; Sheldrick, 2004)		h = −9→8
Tmin = 0.898, Tmax = 1.000k = −12→12
5648 measured reflectionsl = −13→13
Refinement top
Refinement on F20 constraints
Least-squares matrix: fullH-atom parameters constrained
R[F2 > 2σ(F2)] = 0.049 w = 1/[σ2(Fo2) + (0.069P)2 + 0.2975P]
where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.130(Δ/σ)max < 0.001
S = 1.07Δρmax = 0.29 e Å−3
1620 reflectionsΔρmin = −0.34 e Å−3
102 parametersExtinction correction: SHELXL, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
0 restraintsExtinction coefficient: 0.012 (3)
Crystal data top
C7H7NO3V = 705.2 (3) Å3
Mr = 153.14Z = 4
Monoclinic, P21/nMo Kα radiation
a = 7.1061 (14) ŵ = 0.12 mm−1
b = 9.4394 (19) ÅT = 100 K
c = 10.743 (2) Å0.45 × 0.30 × 0.18 mm
β = 101.86 (3)°
Data collection top
Bruker SMART APEX
diffractometer		1620 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 2004)		1497 reflections with I > 2σ(I)
Tmin = 0.898, Tmax = 1.000Rint = 0.032
5648 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0490 restraints
wR(F2) = 0.130H-atom parameters constrained
S = 1.07Δρmax = 0.29 e Å−3
1620 reflectionsΔρmin = −0.34 e Å−3
102 parameters
Special details top

Experimental. Refinement of F2 against unique set of 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 > 2sigma(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.

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 unique set of 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
O10.08533 (15)0.64923 (11)0.35499 (10)0.0257 (3)
O20.22698 (17)0.12565 (12)0.41245 (11)0.0328 (3)
O3−0.00888 (16)0.10699 (11)0.25033 (11)0.0311 (3)
N10.09873 (17)0.17838 (13)0.33088 (11)0.0227 (3)
C10.19682 (19)0.55649 (15)0.43728 (13)0.0200 (3)
C20.31539 (19)0.62992 (15)0.53073 (13)0.0211 (3)
H20.40680.59110.59930.025*
C30.2760 (2)0.77609 (16)0.50590 (15)0.0272 (4)
H30.33600.85390.55450.033*
C40.1374 (2)0.78256 (15)0.40026 (16)0.0278 (4)
H40.08280.86790.36200.033*
C50.18569 (19)0.40627 (15)0.41909 (12)0.0194 (3)
H50.27090.35140.48020.023*
C60.07004 (19)0.33308 (14)0.32658 (12)0.0197 (3)
C7−0.0833 (2)0.38425 (16)0.22071 (14)0.0266 (3)
H7A−0.12450.47910.24090.040*
H7B−0.19320.31930.20920.040*
H7C−0.03360.38810.14220.040*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0287 (6)0.0186 (5)0.0277 (5)0.0010 (4)0.0008 (4)0.0023 (4)
O20.0399 (7)0.0183 (5)0.0339 (6)0.0058 (5)−0.0073 (5)0.0003 (4)
O30.0372 (7)0.0217 (6)0.0304 (6)−0.0050 (4)−0.0023 (5)−0.0073 (4)
N10.0263 (6)0.0186 (6)0.0223 (6)−0.0007 (5)0.0028 (5)−0.0024 (5)
C10.0210 (7)0.0172 (7)0.0222 (7)0.0015 (5)0.0051 (5)0.0019 (5)
C20.0197 (7)0.0216 (7)0.0217 (7)−0.0002 (5)0.0038 (5)−0.0009 (5)
C30.0296 (8)0.0210 (7)0.0324 (8)−0.0057 (6)0.0100 (6)−0.0069 (6)
C40.0321 (8)0.0145 (7)0.0383 (8)0.0012 (6)0.0105 (6)0.0031 (6)
C50.0199 (7)0.0173 (7)0.0206 (6)0.0013 (5)0.0034 (5)0.0010 (5)
C60.0217 (7)0.0164 (6)0.0211 (7)0.0014 (5)0.0047 (5)0.0005 (5)
C70.0292 (8)0.0254 (7)0.0224 (7)0.0037 (6)−0.0014 (6)−0.0020 (6)
Geometric parameters (Å, º) top
O1—C41.3724 (18)C3—C41.342 (2)
O1—C11.3739 (17)C3—H30.9500
O2—N11.2320 (16)C4—H40.9500
O3—N11.2311 (16)C5—C61.3434 (19)
N1—C61.4739 (18)C5—H50.9500
C1—C21.3602 (19)C6—C71.4850 (19)
C1—C51.431 (2)C7—H7A0.9800
C2—C31.422 (2)C7—H7B0.9800
C2—H20.9500C7—H7C0.9800
C4—O1—C1106.17 (12)C3—C4—H4124.6
O3—N1—O2122.73 (12)O1—C4—H4124.6
O3—N1—C6117.28 (11)C6—C5—C1128.22 (13)
O2—N1—C6119.99 (11)C6—C5—H5115.9
C2—C1—O1109.76 (13)C1—C5—H5115.9
C2—C1—C5127.88 (13)C5—C6—N1115.26 (12)
O1—C1—C5122.34 (12)C5—C6—C7129.82 (13)
C1—C2—C3106.73 (13)N1—C6—C7114.92 (12)
C1—C2—H2126.6C6—C7—H7A109.5
C3—C2—H2126.6C6—C7—H7B109.5
C4—C3—C2106.53 (13)H7A—C7—H7B109.5
C4—C3—H3126.7C6—C7—H7C109.5
C2—C3—H3126.7H7A—C7—H7C109.5
C3—C4—O1110.81 (13)H7B—C7—H7C109.5
C4—O1—C1—C2−0.25 (15)O1—C1—C5—C6−1.4 (2)
C4—O1—C1—C5−178.62 (12)C1—C5—C6—N1177.53 (12)
O1—C1—C2—C30.10 (15)C1—C5—C6—C7−2.8 (2)
C5—C1—C2—C3178.36 (13)O3—N1—C6—C5177.57 (12)
C1—C2—C3—C40.08 (16)O2—N1—C6—C5−2.79 (19)
C2—C3—C4—O1−0.24 (17)O3—N1—C6—C7−2.15 (18)
C1—O1—C4—C30.31 (16)O2—N1—C6—C7177.49 (12)
C2—C1—C5—C6−179.46 (13)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C2—H2···O3i0.952.473.3037 (19)147
C5—H5···O3i0.953.033.770 (2)136
C4—H4···O2ii0.952.653.2980 (19)126
C4—H4···O3ii0.952.583.516 (2)170
C7—H7C···O2iii0.982.703.310 (2)121
Symmetry codes: (i) x+1/2, −y+1/2, z+1/2; (ii) x, y+1, z; (iii) x−1/2, −y+1/2, z−1/2.

Experimental details

Crystal data
Chemical formulaC7H7NO3
Mr153.14
Crystal system, space groupMonoclinic, P21/n
Temperature (K)100
a, b, c (Å)7.1061 (14), 9.4394 (19), 10.743 (2)
β (°) 101.86 (3)
V (Å3)705.2 (3)
Z4
Radiation typeMo Kα
µ (mm−1)0.12
Crystal size (mm)0.45 × 0.30 × 0.18
Data collection
DiffractometerBruker SMART APEX
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 2004)
Tmin, Tmax0.898, 1.000
No. of measured, independent and
observed [I > 2σ(I)] reflections		5648, 1620, 1497
Rint0.032
(sin θ/λ)max (Å−1)0.652
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.049, 0.130, 1.07
No. of reflections1620
No. of parameters102
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å−3)0.29, −0.34

Computer programs: SMART (Bruker, 2001), SAINT (Bruker, 2001), SHELXTL (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C2—H2···O3i0.952.473.3037 (19)146.9
C5—H5···O3i0.953.033.770 (2)136.2
C4—H4···O2ii0.952.653.2980 (19)125.7
C4—H4···O3ii0.952.583.516 (2)170.3
C7—H7C···O2iii0.982.703.310 (2)120.9
Symmetry codes: (i) x+1/2, −y+1/2, z+1/2; (ii) x, y+1, z; (iii) x−1/2, −y+1/2, z−1/2.
 

Acknowledgements

We thank the SCCYT (Universidad de Cádiz) for theX-ray data collection and the Consejería de Innovación, Ciencia y Empresa de la Junta de Andalucía, for financial support. ZRN thanks the AUIP and Aula Iberoamericana for the stay at UCA.

References

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ISSN: 2056-9890
Volume 65| Part 8| August 2009| Pages o2060-o2061
doi:10.1107/S1600536809030141
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