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

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ISSN: 2056-9890

Ethyl 5-formyl-2,4-di­methyl-1H-pyrrole-3-carboxyl­ate

aCollege of Science, Nanjing University of Technolgy, Xinmofan Road No.5, Nanjing 210009, People's Republic of China
*Correspondence e-mail: wanghaibo@njut.edu.cn

(Received 12 May 2008; accepted 14 May 2008; online 21 May 2008)

The molecule of the title compound, C10H13NO3, is approximately planar. A network of N—H⋯O and weak C—H⋯O hydrogen bonds helps to consolidate the crystal structure.

Related literature

For related literature, see: Sun et al. (2002[Sun, L., Cui, J., Liang, C. & Zhou, Y. (2002). Bioorg. Med. Chem. Lett. 12, 2153-2157.]). For details of the synthesis, see: Tang et al. (1999[Tang, P.-C., Sun, L. & McMahon, G. (1999). PCT Int. Appl. US 9 912 069.]).

[Scheme 1]

Experimental

Crystal data
  • C10H13NO3

  • Mr = 195.21

  • Monoclinic, P 21 /n

  • a = 3.9830 (8) Å

  • b = 15.572 (3) Å

  • c = 16.213 (3) Å

  • β = 96.96 (3)°

  • V = 998.2 (3) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.10 mm−1

  • T = 293 (2) K

  • 0.20 × 0.05 × 0.05 mm

Data collection
  • Enraf–Nonius CAD-4 diffractometer

  • Absorption correction: ψ scan (North et al., 1968[North, A. C. T., Phillips, D. C. & Mathews, F. S. (1968). Acta Cryst. A24, 351-359.]) Tmin = 0.981, Tmax = 0.995

  • 2069 measured reflections

  • 1798 independent reflections

  • 935 reflections with I > 2σ(I)

  • Rint = 0.021

  • 3 standard reflections every 200 reflections intensity decay: none

Refinement
  • R[F2 > 2σ(F2)] = 0.083

  • wR(F2) = 0.190

  • S = 1.03

  • 1798 reflections

  • 127 parameters

  • H-atom parameters constrained

  • Δρmax = 0.16 e Å−3

  • Δρmin = −0.17 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N—H0A⋯O1i 0.86 2.04 2.864 (5) 159
C1—H1A⋯O3 0.96 2.16 2.882 (5) 131
C6—H6A⋯O1i 0.96 2.58 3.401 (6) 143
C7—H7A⋯O2ii 0.93 2.60 3.525 (6) 176
Symmetry codes: (i) -x, -y, -z+1; (ii) [-x+{\script{3\over 2}}, y+{\script{1\over 2}}, -z+{\script{3\over 2}}].

Data collection: CAD-4 Software (Enraf–Nonius, 1989[Enraf-Nonius (1989). CAD-4 Software. Enraf-Nonius, Delft, The Netherlands.]); cell refinement: CAD-4 Software; data reduction: XCAD4 (Harms & Wocadlo, 1995[Harms, K. & Wocadlo, S. (1995). XCAD4. University of Marburg, Germany.]); 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: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: SHELXL97.

Supporting information


Comment top

As part of our owning studies of pyrrole derivatives (Sun et al., 2002), we report here the crystal structure of the title compound, (I), (Fig. 1), which is approximately planar (for the non-hydrogen atoms, r.m.s. deviation from the mean plane = 0.038Å).

A network of N—H···O and C—H···O hydrogen bonds (Table 1) helps to establish the crystal packing in (I). A short intramolecular C—H···O contact also occurs, based on the geometrically positioned H1A atom, which lies on the mirror plane.

Related literature top

For related literature, see: Sun et al. (2002). For details of the synthesis, see: Tang et al. (1999).

Experimental top

A mixture of 2-tert-butyl 4-ethyl 3,5-dimethyl-1H-pyrrole-2,4-dicarboxylate (30 mmol) in trifluoroacetic acid (40 ml) was stirred for 5 minutes and warmed to 313 K. The mixture was then cooled to 268 K and triethyl orthoformate (45 mmol) was added all at once. The mixture was stirred for about 1 minute, removed from the cold bath and then stirred for 1 h. The trifluoroacetic acid was removed by rotary evaporation and the residue was put into 200 g of ice. The gray floating precipitate was collected by vacuum filtration and washed with 40 ml water then recrystallized twice from ethyl acetate containing Darco carbon black to give 3.7 g of the title compound (Tang et al.,1999). Colourless needles of (I) were obtained by slow evaporation of an ethanol solution.

Refinement top

The H atoms were positioned geometrically (N—H = 0.86 Å, C—H = 0.93 and 0.96 Å) and refined as riding with Uiso(H) =1.2Ueq(carrier) or 1.5Ueq(methyl C).

Computing details top

Data collection: CAD-4 Software (Enraf–Nonius, 1989); cell refinement: CAD-4 Software (Enraf–Nonius, 1989); data reduction: XCAD4 (Harms & Wocadlo, 1995); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The molecular structure of (I), with displacement ellipsoids for the non-H atoms drawn at the 30% probability level. The short intramolecular C—H···O interaction is shown as dashed line.
Ethyl 5-formyl-2,4-dimethyl-1H-pyrrole-3-carboxylate top
Crystal data top
C10H13NO3F(000) = 416
Mr = 195.21Dx = 1.299 Mg m3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ynCell parameters from 25 reflections
a = 3.9830 (8) Åθ = 9–12°
b = 15.572 (3) ŵ = 0.10 mm1
c = 16.213 (3) ÅT = 293 K
β = 96.96 (3)°Needle, colourless
V = 998.2 (3) Å30.20 × 0.05 × 0.05 mm
Z = 4
Data collection top
Enraf–Nonius CAD-4
diffractometer
935 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.021
Graphite monochromatorθmax = 25.2°, θmin = 1.8°
ω/2θ scansh = 44
Absorption correction: ψ scan
(North et al., 1968)
k = 018
Tmin = 0.981, Tmax = 0.995l = 019
2069 measured reflections3 standard reflections every 200 reflections
1798 independent reflections intensity decay: none
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.083Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.190H-atom parameters constrained
S = 1.03 w = 1/[σ2(Fo2) + (0.06P)2 + 0.5P]
where P = (Fo2 + 2Fc2)/3
1798 reflections(Δ/σ)max < 0.001
127 parametersΔρmax = 0.16 e Å3
0 restraintsΔρmin = 0.17 e Å3
Crystal data top
C10H13NO3V = 998.2 (3) Å3
Mr = 195.21Z = 4
Monoclinic, P21/nMo Kα radiation
a = 3.9830 (8) ŵ = 0.10 mm1
b = 15.572 (3) ÅT = 293 K
c = 16.213 (3) Å0.20 × 0.05 × 0.05 mm
β = 96.96 (3)°
Data collection top
Enraf–Nonius CAD-4
diffractometer
935 reflections with I > 2σ(I)
Absorption correction: ψ scan
(North et al., 1968)
Rint = 0.021
Tmin = 0.981, Tmax = 0.9953 standard reflections every 200 reflections
2069 measured reflections intensity decay: none
1798 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0830 restraints
wR(F2) = 0.190H-atom parameters constrained
S = 1.03Δρmax = 0.16 e Å3
1798 reflectionsΔρmin = 0.17 e Å3
127 parameters
Special details top

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 (Å2) top
xyzUiso*/Ueq
N0.3042 (9)0.0589 (2)0.60096 (19)0.0712 (11)
H0A0.18440.06040.55310.085*
O10.0871 (10)0.11115 (17)0.55062 (19)0.0982 (12)
C10.7132 (14)0.0521 (3)0.7869 (3)0.0900 (16)
H1A0.85050.02100.82960.135*
H1B0.52470.07730.80960.135*
H1C0.84590.09650.76560.135*
O20.8180 (10)0.23224 (19)0.76904 (18)0.0989 (12)
C20.5870 (11)0.0078 (3)0.7184 (2)0.0619 (11)
O30.9364 (8)0.11553 (16)0.84573 (16)0.0802 (10)
C30.6177 (10)0.0982 (2)0.7165 (2)0.0575 (10)
C40.4352 (13)0.1260 (3)0.6409 (3)0.0781 (14)
C50.3840 (12)0.0144 (2)0.6459 (2)0.0719 (13)
C60.3837 (13)0.2149 (3)0.6079 (3)0.0840 (15)
H6A0.24640.21320.55500.126*
H6B0.27250.24870.64600.126*
H6C0.59890.24010.60150.126*
C70.2893 (14)0.0965 (3)0.6142 (3)0.0825 (15)
H7A0.38570.14370.64320.099*
C80.7874 (12)0.1552 (3)0.7771 (2)0.0656 (11)
C91.1202 (13)0.1682 (3)0.9080 (2)0.0797 (14)
H9A1.30170.19810.88520.096*
H9B0.97130.21050.92830.096*
C101.2602 (13)0.1105 (3)0.9765 (3)0.0888 (15)
H10A1.38650.14371.01950.133*
H10B1.07820.08150.99880.133*
H10C1.40630.06880.95560.133*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
N0.073 (3)0.071 (2)0.0652 (18)0.004 (2)0.0076 (18)0.0032 (16)
O10.125 (3)0.0727 (18)0.0864 (19)0.006 (2)0.029 (2)0.0039 (15)
C10.110 (5)0.072 (3)0.086 (3)0.002 (3)0.001 (3)0.004 (2)
O20.130 (4)0.0705 (19)0.092 (2)0.009 (2)0.004 (2)0.0027 (15)
C20.053 (3)0.076 (3)0.0595 (19)0.001 (2)0.0175 (18)0.0012 (18)
O30.094 (3)0.0629 (16)0.0791 (18)0.0052 (19)0.0082 (17)0.0004 (14)
C30.047 (3)0.069 (2)0.060 (2)0.007 (2)0.0210 (18)0.0007 (17)
C40.088 (4)0.069 (3)0.077 (3)0.020 (3)0.007 (2)0.002 (2)
C50.071 (3)0.055 (2)0.083 (3)0.010 (2)0.017 (2)0.002 (2)
C60.094 (4)0.071 (3)0.086 (3)0.011 (3)0.003 (3)0.017 (2)
C70.101 (4)0.075 (3)0.069 (2)0.009 (3)0.001 (3)0.003 (2)
C80.061 (3)0.065 (2)0.074 (2)0.002 (3)0.020 (2)0.002 (2)
C90.090 (4)0.068 (2)0.077 (3)0.012 (3)0.003 (3)0.003 (2)
C100.084 (4)0.089 (3)0.091 (3)0.012 (3)0.003 (3)0.007 (2)
Geometric parameters (Å, º) top
N—C41.304 (5)C3—C81.432 (5)
N—C51.370 (5)C4—C61.489 (5)
N—H0A0.8600C5—C71.412 (5)
O1—C71.250 (5)C6—H6A0.9600
C1—C21.490 (5)C6—H6B0.9600
C1—H1A0.9600C6—H6C0.9600
C1—H1B0.9600C7—H7A0.9300
C1—H1C0.9600C9—C101.484 (5)
O2—C81.214 (4)C9—H9A0.9700
C2—C51.388 (5)C9—H9B0.9700
C2—C31.414 (5)C10—H10A0.9600
O3—C81.346 (4)C10—H10B0.9600
O3—C91.431 (4)C10—H10C0.9600
C3—C41.415 (5)
C4—N—C5110.5 (3)C4—C6—H6B109.5
C4—N—H0A124.7H6A—C6—H6B109.5
C5—N—H0A124.7C4—C6—H6C109.5
C2—C1—H1A109.5H6A—C6—H6C109.5
C2—C1—H1B109.5H6B—C6—H6C109.5
H1A—C1—H1B109.5O1—C7—C5125.6 (4)
C2—C1—H1C109.5O1—C7—H7A117.2
H1A—C1—H1C109.5C5—C7—H7A117.2
H1B—C1—H1C109.5O2—C8—O3120.2 (4)
C5—C2—C3105.8 (3)O2—C8—C3125.7 (4)
C5—C2—C1125.8 (4)O3—C8—C3114.0 (3)
C3—C2—C1128.1 (4)O3—C9—C10107.2 (3)
C8—O3—C9117.2 (3)O3—C9—H9A110.3
C2—C3—C4106.7 (3)C10—C9—H9A110.3
C2—C3—C8129.5 (4)O3—C9—H9B110.3
C4—C3—C8123.7 (4)C10—C9—H9B110.3
N—C4—C3108.5 (3)H9A—C9—H9B108.5
N—C4—C6122.5 (4)C9—C10—H10A109.5
C3—C4—C6129.0 (4)C9—C10—H10B109.5
N—C5—C2108.5 (3)H10A—C10—H10B109.5
N—C5—C7121.8 (3)C9—C10—H10C109.5
C2—C5—C7129.5 (4)H10A—C10—H10C109.5
C4—C6—H6A109.5H10B—C10—H10C109.5
C5—C2—C3—C41.3 (5)C1—C2—C5—N176.2 (4)
C1—C2—C3—C4175.6 (5)C3—C2—C5—C7175.8 (5)
C5—C2—C3—C8177.2 (4)C1—C2—C5—C79.7 (8)
C1—C2—C3—C82.9 (8)N—C5—C7—O111.4 (8)
C5—N—C4—C30.7 (5)C2—C5—C7—O1175.2 (5)
C5—N—C4—C6178.6 (5)C9—O3—C8—O21.6 (7)
C2—C3—C4—N0.4 (5)C9—O3—C8—C3178.1 (4)
C8—C3—C4—N178.2 (4)C2—C3—C8—O2175.8 (5)
C2—C3—C4—C6179.6 (5)C4—C3—C8—O25.8 (8)
C8—C3—C4—C60.9 (8)C2—C3—C8—O30.4 (7)
C4—N—C5—C21.6 (5)C4—C3—C8—O3177.9 (4)
C4—N—C5—C7176.2 (5)C8—O3—C9—C10179.8 (4)
C3—C2—C5—N1.7 (5)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N—H0A···O1i0.862.042.864 (5)159
C1—H1A···O30.962.162.882 (5)131
C6—H6A···O1i0.962.583.401 (6)143
C7—H7A···O2ii0.932.603.525 (6)176
Symmetry codes: (i) x, y, z+1; (ii) x+3/2, y+1/2, z+3/2.

Experimental details

Crystal data
Chemical formulaC10H13NO3
Mr195.21
Crystal system, space groupMonoclinic, P21/n
Temperature (K)293
a, b, c (Å)3.9830 (8), 15.572 (3), 16.213 (3)
β (°) 96.96 (3)
V3)998.2 (3)
Z4
Radiation typeMo Kα
µ (mm1)0.10
Crystal size (mm)0.20 × 0.05 × 0.05
Data collection
DiffractometerEnraf–Nonius CAD-4
diffractometer
Absorption correctionψ scan
(North et al., 1968)
Tmin, Tmax0.981, 0.995
No. of measured, independent and
observed [I > 2σ(I)] reflections
2069, 1798, 935
Rint0.021
(sin θ/λ)max1)0.598
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.083, 0.190, 1.03
No. of reflections1798
No. of parameters127
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.16, 0.17

Computer programs: CAD-4 Software (Enraf–Nonius, 1989), XCAD4 (Harms & Wocadlo, 1995), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N—H0A···O1i0.862.042.864 (5)159
C1—H1A···O30.962.162.882 (5)131
C6—H6A···O1i0.962.583.401 (6)143
C7—H7A···O2ii0.932.603.525 (6)176
Symmetry codes: (i) x, y, z+1; (ii) x+3/2, y+1/2, z+3/2.
 

References

First citationEnraf–Nonius (1989). CAD-4 Software. Enraf–Nonius, Delft, The Netherlands.  Google Scholar
First citationHarms, K. & Wocadlo, S. (1995). XCAD4. University of Marburg, Germany.  Google Scholar
First citationNorth, A. C. T., Phillips, D. C. & Mathews, F. S. (1968). Acta Cryst. A24, 351–359.  CrossRef IUCr Journals Web of Science Google Scholar
First citationSheldrick, G. M. (2008). Acta Cryst. A64, 112–122.  Web of Science CrossRef CAS IUCr Journals Google Scholar
First citationSun, L., Cui, J., Liang, C. & Zhou, Y. (2002). Bioorg. Med. Chem. Lett. 12, 2153–2157.  Web of Science CrossRef PubMed CAS Google Scholar
First citationTang, P.-C., Sun, L. & McMahon, G. (1999). PCT Int. Appl. US 9 912 069.  Google Scholar

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ISSN: 2056-9890
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