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

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ISSN: 2056-9890

Di­ethyl 2-{[(4-meth­­oxy-3-pyrid­yl)amino]­methyl­­idene}malonate

aSchool of Chemistry and Chemical Engineering, Yulin University, Yulin 719000, People's Republic of China
*Correspondence e-mail: zhifang889@126.com

(Received 30 June 2011; accepted 3 July 2011; online 9 July 2011)

In the title mol­ecule, C14H8N2O5, the amino group is involved in the formation an intra­molecular N—H⋯O hydrogen bond. In the crystal, weak inter­molecular C—H⋯O and C—H⋯N hydrogen bonds link the mol­ecules into ribbons along the b axis.

Related literature

For details of the synthesis, see: Brown & Dewar (1978[Brown, S. B. & Dewar, M. J. S. (1978). J. Org. Chem. 43, 1331-1337.]). For related structures, see: Thenmozhi et al. (2009[Thenmozhi, S., Ranjith, S., SubbiahPandi, A., Dhayalan, V. & MohanaKrishnan, A. K. (2009). Acta Cryst. E65, o2209.]); Feng et al. (2010[Feng, Z.-Q., Yang, X.-L., Ye, Y.-F., Dong, T. & Wang, H.-Q. (2010). Acta Cryst. E66, o3119.]). For potential applications of metal complexes with β-diketone derivatives, see: Nishihama et al. (2001[Nishihama, S., Hirai, T. & Komasawa, I. (2001). Ind. Eng. Chem. Res. 40, 3085-3091.]); Soldatov et al. (2003[Soldatov, D. V., Tinnemans, P., Enright, G. D., Ratcliff, C. I., Diamente, P. R. & Ripmeester, J. A. (2003). Chem. Mater. 15, 3826-3840.]). For bond-length data, see: Allen et al. (1987[Allen, F. H., Kennard, O., Watson, D. G., Brammer, L., Orpen, A. G. & Taylor, R. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1-19.]).

[Scheme 1]

Experimental

Crystal data
  • C14H18N2O5

  • Mr = 294.30

  • Monoclinic, P 21 /c

  • a = 19.012 (4) Å

  • b = 8.6620 (17) Å

  • c = 9.1600 (18) Å

  • β = 94.08 (3)°

  • V = 1504.7 (5) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.10 mm−1

  • T = 295 K

  • 0.30 × 0.20 × 0.10 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 = 0.971, Tmax = 0.990

  • 2843 measured reflections

  • 2758 independent reflections

  • 1452 reflections with I > 2σ(I)

  • Rint = 0.034

  • 3 standard reflections every 200 reflections intensity decay: 1%

Refinement
  • R[F2 > 2σ(F2)] = 0.059

  • wR(F2) = 0.142

  • S = 1.01

  • 2758 reflections

  • 190 parameters

  • H-atom parameters constrained

  • Δρmax = 0.16 e Å−3

  • Δρmin = −0.14 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N2—H2A⋯O4 0.86 2.01 2.656 (3) 131
C6—H6A⋯O2i 0.96 2.57 3.462 (4) 155
C2—H2B⋯N1ii 0.93 2.63 3.389 (3) 139
Symmetry codes: (i) x, y-1, z; (ii) [-x, y-{\script{1\over 2}}, -z+{\script{1\over 2}}].

Data collection: CAD-4 Software (Enraf–Nonius, 1985[Enraf-Nonius (1985). 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: SHELXTL.

Supporting information


Comment top

β-Diketone as an chelating group has been widely used in supramolecular chemistry. Their metal complexes are used for the separation of elements with similar properties (Nishihama et al., 2001). These metal complexes have applications in materials science or act as NMR shift reagents (Soldatov et al., 2003). The tittle compound, (I), is a derivative of β-diketone. Herewith we present its crystal structure.

In (I) (Fig. 1), the amino group is involved in formation an intramolecular N—H···O hydrogen bond (Table 1). The bond lengths and angles are within normal ranges (Allen et al., 1987) and correspond to those observed in the related compounds (Thenmozhi et al., 2009; Feng et al., 2010).

In the crystal structure, weak intermolecular C—H···O and C—H···N hydrogen bonds (Table 1) link molecules into approximately planar ribbons along the b axis.

Related literature top

For details of the synthesis, see: Brown et al. (1978). For related structures, see: Thenmozhi et al. (2009); Feng et al. (2010). For potential applications of metal complexes with β-diketone derivatives, see: Nishihama et al. (2001); Soldatov et al. (2003). For bond-length data, see: Allen et al. (1987).

Experimental top

The title compound was synthesized according to the method proposed by Brown & Dewar (1978). A mixture of 3-Nitro-4-methoxypyridine (5 g; 0.0325 mol), 10% palladium on carbon (500 mg), and dry methanol (125 ml) was hydrogenated for 6 h in a Parr apparatus at 50 psi. Filtration of the mixture through Celite and evaporation of the filtrate yielded the crude amine as a light tan oil or solid. The amine was stirred and refluxed in toluene (100 ml) with ethoxymethylenemalonic ester(EMME; 7 g; 0.0325 mol) for 24 hand then the reaction mixture was evaporated to dryness. The residue was dissolved in boiling Skelly B, filtered by gravity, and cooled to room temperature. The title compound crystallized as fine, white platelets.

Refinement top

H atoms were positioned geometrically [N—H 0.86 Å; C—H 0.93-0.97 Å], and constrained to ride on their parent atoms, with Uiso(H) = 1.2-1.5 Ueq(C, N).

Computing details top

Data collection: CAD-4 Software (Enraf–Nonius, 1985); cell refinement: CAD-4 Software (Enraf–Nonius, 1985); data reduction: XCAD4 (Harms & Wocadlo, 1995); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXS97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The molecular structure of (I) showing the atomic numbering and 30% probabilty displacement ellipsoids.
Diethyl 2-{[(4-methoxy-3-pyridyl)amino]methylidene}malonate top
Crystal data top
C14H18N2O5F(000) = 624
Mr = 294.30Dx = 1.299 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 25 reflections
a = 19.012 (4) Åθ = 10–13°
b = 8.6620 (17) ŵ = 0.10 mm1
c = 9.1600 (18) ÅT = 295 K
β = 94.08 (3)°Block, colourless
V = 1504.7 (5) Å30.30 × 0.20 × 0.10 mm
Z = 4
Data collection top
Enraf–Nonius CAD-4
diffractometer
1452 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.034
Graphite monochromatorθmax = 25.4°, θmin = 1.1°
ω/2θ scansh = 220
Absorption correction: ψ scan
(North et al., 1968)
k = 010
Tmin = 0.971, Tmax = 0.990l = 1011
2843 measured reflections3 standard reflections every 200 reflections
2758 independent reflections intensity decay: 1%
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)] = 0.059Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.142H-atom parameters constrained
S = 1.01 w = 1/[σ2(Fo2) + (0.056P)2]
where P = (Fo2 + 2Fc2)/3
2758 reflections(Δ/σ)max < 0.001
190 parametersΔρmax = 0.16 e Å3
0 restraintsΔρmin = 0.14 e Å3
Crystal data top
C14H18N2O5V = 1504.7 (5) Å3
Mr = 294.30Z = 4
Monoclinic, P21/cMo Kα radiation
a = 19.012 (4) ŵ = 0.10 mm1
b = 8.6620 (17) ÅT = 295 K
c = 9.1600 (18) Å0.30 × 0.20 × 0.10 mm
β = 94.08 (3)°
Data collection top
Enraf–Nonius CAD-4
diffractometer
1452 reflections with I > 2σ(I)
Absorption correction: ψ scan
(North et al., 1968)
Rint = 0.034
Tmin = 0.971, Tmax = 0.9903 standard reflections every 200 reflections
2843 measured reflections intensity decay: 1%
2758 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0590 restraints
wR(F2) = 0.142H-atom parameters constrained
S = 1.01Δρmax = 0.16 e Å3
2758 reflectionsΔρmin = 0.14 e Å3
190 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
O10.15081 (10)0.3780 (2)0.5511 (2)0.0649 (6)
C10.11221 (14)0.4906 (3)0.4828 (3)0.0502 (7)
N10.03465 (13)0.7408 (3)0.3671 (3)0.0668 (7)
N20.17585 (11)0.6573 (2)0.6532 (2)0.0527 (6)
H2A0.19160.57420.69540.063*
O20.25551 (12)1.0765 (2)0.7731 (2)0.0826 (8)
C20.06290 (15)0.4714 (3)0.3677 (3)0.0591 (8)
H2B0.05430.37440.32680.071*
O30.31389 (12)0.9837 (2)0.9718 (2)0.0868 (8)
C30.02656 (15)0.5984 (4)0.3142 (3)0.0645 (9)
H3A0.00620.58400.23500.077*
O40.26443 (12)0.5409 (2)0.8621 (2)0.0804 (7)
C40.08378 (14)0.7576 (3)0.4773 (3)0.0590 (8)
H4A0.09160.85630.51500.071*
O50.34811 (10)0.6944 (2)0.9616 (2)0.0662 (6)
C50.12345 (14)0.6392 (3)0.5386 (3)0.0463 (7)
C60.14403 (17)0.2247 (3)0.4922 (4)0.0776 (10)
H6A0.17400.15580.55030.116*
H6B0.15760.22450.39330.116*
H6C0.09590.19130.49370.116*
C70.20362 (14)0.7889 (3)0.7033 (3)0.0528 (7)
H7A0.18540.87890.66010.063*
C80.25623 (14)0.8065 (3)0.8119 (3)0.0484 (7)
C90.27475 (15)0.9670 (3)0.8476 (3)0.0591 (8)
C100.3349 (2)1.1375 (4)1.0158 (5)0.1076 (14)
H10A0.33931.20150.93010.129*
H10B0.29961.18311.07390.129*
C110.4004 (2)1.1295 (4)1.0990 (5)0.1279 (16)
H11A0.41441.23131.13050.192*
H11B0.43531.08691.03990.192*
H11C0.39581.06491.18290.192*
C120.28810 (15)0.6696 (3)0.8807 (3)0.0526 (7)
C130.38151 (16)0.5613 (3)1.0303 (3)0.0721 (9)
H13A0.40130.49610.95760.087*
H13B0.34750.50141.08040.087*
C140.43854 (18)0.6193 (4)1.1373 (4)0.0959 (12)
H14A0.46210.53331.18550.144*
H14B0.41830.68361.20860.144*
H14C0.47190.67811.08640.144*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0708 (14)0.0499 (12)0.0701 (13)0.0029 (10)0.0218 (11)0.0015 (10)
C10.0463 (16)0.0575 (17)0.0455 (15)0.0011 (14)0.0067 (13)0.0004 (13)
N10.0626 (17)0.0728 (17)0.0629 (16)0.0032 (14)0.0106 (13)0.0104 (14)
N20.0607 (15)0.0465 (14)0.0490 (13)0.0003 (12)0.0088 (11)0.0020 (11)
O20.1070 (19)0.0537 (13)0.0823 (16)0.0006 (12)0.0257 (14)0.0033 (11)
C20.0626 (19)0.0608 (19)0.0523 (17)0.0071 (16)0.0065 (15)0.0006 (15)
O30.1061 (18)0.0546 (13)0.0922 (17)0.0018 (12)0.0465 (14)0.0092 (11)
C30.060 (2)0.080 (2)0.0512 (18)0.0070 (17)0.0126 (15)0.0049 (16)
O40.0954 (17)0.0519 (13)0.0881 (16)0.0083 (12)0.0342 (13)0.0069 (11)
C40.0562 (19)0.0590 (18)0.0601 (18)0.0002 (15)0.0084 (15)0.0010 (15)
O50.0625 (13)0.0543 (12)0.0786 (14)0.0005 (10)0.0184 (11)0.0023 (10)
C50.0471 (16)0.0533 (17)0.0379 (14)0.0012 (14)0.0017 (12)0.0030 (12)
C60.086 (2)0.0476 (19)0.096 (3)0.0027 (17)0.0172 (19)0.0094 (17)
C70.0563 (18)0.0485 (17)0.0533 (17)0.0021 (15)0.0018 (14)0.0020 (14)
C80.0485 (16)0.0480 (16)0.0482 (15)0.0025 (14)0.0003 (13)0.0016 (13)
C90.0544 (19)0.059 (2)0.0629 (19)0.0010 (16)0.0062 (15)0.0029 (16)
C100.115 (3)0.055 (2)0.142 (3)0.004 (2)0.063 (3)0.021 (2)
C110.120 (3)0.090 (3)0.164 (4)0.022 (3)0.063 (3)0.002 (3)
C120.0569 (19)0.0520 (18)0.0481 (16)0.0066 (15)0.0020 (15)0.0035 (14)
C130.071 (2)0.069 (2)0.073 (2)0.0150 (18)0.0134 (18)0.0041 (17)
C140.078 (2)0.110 (3)0.095 (3)0.014 (2)0.028 (2)0.000 (2)
Geometric parameters (Å, º) top
O1—C11.348 (3)C6—H6A0.9600
O1—C61.436 (3)C6—H6B0.9600
C1—C21.370 (3)C6—H6C0.9600
C1—C51.396 (3)C7—C81.368 (3)
N1—C31.330 (4)C7—H7A0.9300
N1—C41.333 (3)C8—C121.455 (4)
N2—C71.325 (3)C8—C91.465 (4)
N2—C51.404 (3)C10—C111.414 (4)
N2—H2A0.8600C10—H10A0.9700
O2—C91.210 (3)C10—H10B0.9700
C2—C31.371 (4)C11—H11A0.9600
C2—H2B0.9300C11—H11B0.9600
O3—C91.323 (3)C11—H11C0.9600
O3—C101.440 (3)C13—C141.495 (4)
C3—H3A0.9300C13—H13A0.9700
O4—C121.209 (3)C13—H13B0.9700
C4—C51.370 (3)C14—H14A0.9600
C4—H4A0.9300C14—H14B0.9600
O5—C121.333 (3)C14—H14C0.9600
O5—C131.440 (3)
C1—O1—C6117.6 (2)C7—C8—C9114.8 (2)
O1—C1—C2126.1 (3)C12—C8—C9126.2 (2)
O1—C1—C5115.6 (2)O2—C9—O3121.9 (3)
C2—C1—C5118.2 (3)O2—C9—C8124.0 (3)
C3—N1—C4115.7 (3)O3—C9—C8114.1 (3)
C7—N2—C5126.8 (2)C11—C10—O3108.8 (3)
C7—N2—H2A116.6C11—C10—H10A109.9
C5—N2—H2A116.6O3—C10—H10A109.9
C1—C2—C3118.5 (3)C11—C10—H10B109.9
C1—C2—H2B120.7O3—C10—H10B109.9
C3—C2—H2B120.7H10A—C10—H10B108.3
C9—O3—C10118.0 (2)C10—C11—H11A109.5
N1—C3—C2124.9 (3)C10—C11—H11B109.5
N1—C3—H3A117.6H11A—C11—H11B109.5
C2—C3—H3A117.6C10—C11—H11C109.5
N1—C4—C5124.4 (3)H11A—C11—H11C109.5
N1—C4—H4A117.8H11B—C11—H11C109.5
C5—C4—H4A117.8O4—C12—O5121.5 (3)
C12—O5—C13116.6 (2)O4—C12—C8123.4 (3)
C4—C5—C1118.3 (2)O5—C12—C8115.0 (2)
C4—C5—N2124.3 (2)O5—C13—C14107.1 (3)
C1—C5—N2117.3 (2)O5—C13—H13A110.3
O1—C6—H6A109.5C14—C13—H13A110.3
O1—C6—H6B109.5O5—C13—H13B110.3
H6A—C6—H6B109.5C14—C13—H13B110.3
O1—C6—H6C109.5H13A—C13—H13B108.5
H6A—C6—H6C109.5C13—C14—H14A109.5
H6B—C6—H6C109.5C13—C14—H14B109.5
N2—C7—C8126.9 (3)H14A—C14—H14B109.5
N2—C7—H7A116.5C13—C14—H14C109.5
C8—C7—H7A116.5H14A—C14—H14C109.5
C7—C8—C12119.0 (2)H14B—C14—H14C109.5
C6—O1—C1—C25.0 (4)N2—C7—C8—C121.7 (4)
C6—O1—C1—C5176.5 (2)N2—C7—C8—C9178.1 (3)
O1—C1—C2—C3177.8 (3)C10—O3—C9—O21.4 (5)
C5—C1—C2—C30.7 (4)C10—O3—C9—C8179.8 (3)
C4—N1—C3—C22.2 (4)C7—C8—C9—O212.7 (4)
C1—C2—C3—N11.1 (5)C12—C8—C9—O2167.5 (3)
C3—N1—C4—C51.7 (4)C7—C8—C9—O3166.0 (3)
N1—C4—C5—C10.1 (4)C12—C8—C9—O313.8 (4)
N1—C4—C5—N2179.1 (3)C9—O3—C10—C11150.4 (4)
O1—C1—C5—C4177.5 (2)C13—O5—C12—O42.5 (4)
C2—C1—C5—C41.1 (4)C13—O5—C12—C8179.5 (2)
O1—C1—C5—N23.4 (4)C7—C8—C12—O410.7 (4)
C2—C1—C5—N2177.9 (2)C9—C8—C12—O4169.1 (3)
C7—N2—C5—C412.2 (4)C7—C8—C12—O5166.2 (2)
C7—N2—C5—C1166.8 (3)C9—C8—C12—O514.0 (4)
C5—N2—C7—C8177.8 (3)C12—O5—C13—C14168.9 (3)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N2—H2A···O40.862.012.656 (3)131
C6—H6A···O2i0.962.573.462 (4)155
C2—H2B···N1ii0.932.633.389 (3)139
Symmetry codes: (i) x, y1, z; (ii) x, y1/2, z+1/2.

Experimental details

Crystal data
Chemical formulaC14H18N2O5
Mr294.30
Crystal system, space groupMonoclinic, P21/c
Temperature (K)295
a, b, c (Å)19.012 (4), 8.6620 (17), 9.1600 (18)
β (°) 94.08 (3)
V3)1504.7 (5)
Z4
Radiation typeMo Kα
µ (mm1)0.10
Crystal size (mm)0.30 × 0.20 × 0.10
Data collection
DiffractometerEnraf–Nonius CAD-4
diffractometer
Absorption correctionψ scan
(North et al., 1968)
Tmin, Tmax0.971, 0.990
No. of measured, independent and
observed [I > 2σ(I)] reflections
2843, 2758, 1452
Rint0.034
(sin θ/λ)max1)0.603
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.059, 0.142, 1.01
No. of reflections2758
No. of parameters190
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.16, 0.14

Computer programs: CAD-4 Software (Enraf–Nonius, 1985), XCAD4 (Harms & Wocadlo, 1995), SHELXS97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N2—H2A···O40.862.012.656 (3)131
C6—H6A···O2i0.962.573.462 (4)155
C2—H2B···N1ii0.932.633.389 (3)139
Symmetry codes: (i) x, y1, z; (ii) x, y1/2, z+1/2.
 

Acknowledgements

The author gratefully acknowledges financial support from the Scientific Research Foundation for High-Level Personnel, Yulin University (grant No. 11 GK03) and the Collaboration Programs of Yulin City and Universities.

References

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