Ethyl 4-amino-5-cyano-2-methyl-6-(2-nitro­phen­oxy)nicotinate

Ren, Q.-Y.; He, H.-W.; Yao, Y.-Y.; Gu, Y.-C.

doi:10.1107/S1600536807049616

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Ethyl 4-amino-5-cyano-2-methyl-6-(2-nitrophenoxy)nicotinate

Q.-Y. Ren, H.-W. He, Y.-Y. Yao and Y.-C. Gu

In the title compound, C₁₆H₁₄N₄O₅, the benzene ring of the nicotinate residue is inclined at an angle of 64.06 (10)° to the benzene ring of the nitrophenoxy group. The molecules are linked by two intermolecular C—H

O and N—H

N hydrogen bonds into a complex three-dimensional framework structure. C—H

π interactions also contribute to the stability of the crystal packing.

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Supporting information

	Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536807049616/sj2374sup1.cif Contains datablocks I, global
	Structure factor file (CIF format) https://doi.org/10.1107/S1600536807049616/sj2374Isup2.hkl Contains datablock I

CCDC reference: 662948

checkCIF report

Key indicators

Single-crystal X-ray study
T = 294 K
Mean (C-C) = 0.003 Å
R factor = 0.049
wR factor = 0.167
Data-to-parameter ratio = 13.4

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT154_ALERT_1_C The su's on the Cell Angles are Equal  (x 10000)        100 Deg.
PLAT180_ALERT_3_C Check Cell Rounding: # of Values Ending with 0 =          3
PLAT220_ALERT_2_C Large Non-Solvent    O     Ueq(max)/Ueq(min) ...       2.77 Ratio
PLAT242_ALERT_2_C Check Low       Ueq as Compared to Neighbors for         N4
PLAT371_ALERT_2_C Long   C(sp2)-C(sp1) Bond  C3     -   C10    ...       1.43 Ang.

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

   1 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   3 ALERT type 2 Indicator that the structure model may be wrong or deficient
   1 ALERT type 3 Indicator that the structure quality may be low
   0 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

Comment top

Pyridine derivatives are important compounds because of their presence in numerous natural products. For example, nicotine is found in a wide variety of plants, which play important roles in metabolism and possess a wide spectrum of biological activity (Yildiz, 2004). We report here the molecular structure of the nicotinate derivative (I) (Fig. 1). In the title compound, all bond lengths and angles are within normal ranges (Allen et al., 1987) and the molecules are linked by two intermolecular C—H···O and N—H···N hydrogen bonds into a complex three-dimensional framework structure (Fig. 2). Weak C—H···π interactions (Table 1, Cg is a centroid of the N1/C4/C3/C2/C1/C5 ring) also contribute to the crystal packing stability.

Related literature top

For the biological importance of nicotine derivatives, see Yildiz (2004). For reference structural data, see Allen et al. (1987).

Experimental top

A mixture of 4-amino-5-cyano-6-methanesulfonyl-2-methyl-nicotinic acid ethyl ester (1.4 g, 5 mmol) and catalytic solid K₂CO₃ (0.012 g, 0.1 mmol) were added to a solution of 2-nitro-phenol (0.7 g, 5 mmol) in anhydrous ethanol (20 ml), stirred for 2 h at 341 K and filtered. The filtrate was condensed and the residue recrystallized from dichloromethane/ petroleum ether to give pure 4-amino-5-cyano-2-methyl-6-(2-nitro-phenoxy)-nicotinic acid ethyl ester (yield 86%). Crystals of (I) suitable for X-ray structure analysis were grown from ethanol.

Structure description top

For the biological importance of nicotine derivatives, see Yildiz (2004). For reference structural data, see Allen et al. (1987).

Computing details top

Data collection: SMART (Bruker, 2001); cell refinement: SAINT (Bruker, 2001); data reduction: SAINT (Bruker, 2001); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: PLATON (Spek, 2003); software used to prepare material for publication: SHELXTL (Sheldrick, 2001).

Figures top

	Fig. 1. The structure of (I). showing 50% probability displacement ellipsoids and the atom-numbering scheme.
	Fig. 2. Part of the crystal packing of (I) showing the formation of dimers linked by hydrogen-bonds (dashed lines).

Ethyl 4-amino-5-cyano-2-methyl-6-(2-nitrophenoxy)nicotinate top

Crystal data top

C₁₆H₁₄N₄O₅	Z = 2
M_r = 342.31	F(000) = 356
Triclinic, P1	D_x = 1.404 Mg m⁻³
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 7.9831 (6) Å	Cell parameters from 2185 reflections
b = 8.8661 (7) Å	θ = 2.5–24.8°
c = 12.2797 (10) Å	µ = 0.11 mm⁻¹
α = 69.012 (1)°	T = 294 K
β = 86.342 (1)°	Block, yellow
γ = 88.835 (1)°	0.30 × 0.20 × 0.20 mm
V = 809.83 (11) Å³

Data collection top

Bruker SMART APEX CCD area-detector diffractometer	2146 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	R_int = 0.023
Graphite monochromator	θ_max = 26.0°, θ_min = 1.8°
φ and ω scans	h = −9→9
8410 measured reflections	k = −9→10
3145 independent reflections	l = −15→15

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.049	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.167	H atoms treated by a mixture of independent and constrained refinement
S = 1.07	w = 1/[σ²(F_o²) + (0.0992P)²] where P = (F_o² + 2F_c²)/3
3145 reflections	(Δ/σ)_max < 0.001
235 parameters	Δρ_max = 0.22 e Å⁻³
0 restraints	Δρ_min = −0.20 e Å⁻³

Crystal data top

C₁₆H₁₄N₄O₅	γ = 88.835 (1)°
M_r = 342.31	V = 809.83 (11) Å³
Triclinic, P1	Z = 2
a = 7.9831 (6) Å	Mo Kα radiation
b = 8.8661 (7) Å	µ = 0.11 mm⁻¹
c = 12.2797 (10) Å	T = 294 K
α = 69.012 (1)°	0.30 × 0.20 × 0.20 mm
β = 86.342 (1)°

Data collection top

Bruker SMART APEX CCD area-detector diffractometer	2146 reflections with I > 2σ(I)
8410 measured reflections	R_int = 0.023
3145 independent reflections

Refinement top

R[F² > 2σ(F²)] = 0.049	0 restraints
wR(F²) = 0.167	H atoms treated by a mixture of independent and constrained refinement
S = 1.07	Δρ_max = 0.22 e Å⁻³
3145 reflections	Δρ_min = −0.20 e Å⁻³
235 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

	x	y	z	U_iso*/U_eq
C1	0.2580 (2)	0.4848 (2)	0.52656 (15)	0.0386 (4)
C2	0.3286 (2)	0.6325 (2)	0.52562 (14)	0.0370 (4)
C3	0.3988 (2)	0.6298 (2)	0.62939 (15)	0.0395 (4)
C4	0.3964 (2)	0.4853 (2)	0.72421 (15)	0.0410 (5)
C5	0.2584 (2)	0.3490 (2)	0.63016 (15)	0.0406 (5)
C6	0.1914 (2)	0.4850 (2)	0.41669 (15)	0.0410 (5)
C7	0.0793 (3)	0.3396 (3)	0.31026 (17)	0.0582 (6)
H7A	0.1691	0.3657	0.2494	0.070*
H7B	−0.0098	0.4180	0.2844	0.070*
C8	0.0149 (3)	0.1740 (3)	0.3342 (2)	0.0666 (7)
H8A	0.1043	0.0976	0.3587	0.100*
H8B	−0.0281	0.1683	0.2645	0.100*
H8C	−0.0733	0.1492	0.3949	0.100*
C9	0.1826 (3)	0.1880 (2)	0.64853 (17)	0.0545 (6)
H9A	0.2494	0.1351	0.6051	0.082*
H9B	0.0707	0.2029	0.6221	0.082*
H9C	0.1790	0.1227	0.7301	0.082*
C10	0.4724 (2)	0.7727 (2)	0.63351 (15)	0.0444 (5)
C11	0.4771 (3)	0.3499 (2)	0.91776 (16)	0.0470 (5)
C12	0.3363 (3)	0.2736 (3)	0.98573 (16)	0.0536 (6)
C13	0.3529 (3)	0.1356 (3)	1.08299 (17)	0.0643 (6)
H13	0.2578	0.0829	1.1267	0.077*
C14	0.5091 (3)	0.0763 (3)	1.11508 (18)	0.0649 (7)
H14	0.5206	−0.0165	1.1806	0.078*
C15	0.6482 (3)	0.1545 (3)	1.05021 (19)	0.0659 (7)
H15	0.7544	0.1158	1.0729	0.079*
C16	0.6325 (3)	0.2898 (3)	0.95177 (17)	0.0569 (6)
H16	0.7281	0.3409	0.9079	0.068*
N1	0.3292 (2)	0.35024 (18)	0.72735 (13)	0.0438 (4)
N2	0.3315 (2)	0.7694 (2)	0.43277 (15)	0.0493 (5)
H2A	0.376 (3)	0.855 (3)	0.4358 (18)	0.059*
H2B	0.280 (3)	0.763 (2)	0.3694 (18)	0.059*
N3	0.5293 (3)	0.8913 (2)	0.63011 (14)	0.0612 (5)
O1	0.1840 (2)	0.60489 (18)	0.32916 (12)	0.0663 (5)
O2	0.14144 (18)	0.34349 (16)	0.41824 (11)	0.0534 (4)
O3	0.47215 (18)	0.49029 (15)	0.81893 (11)	0.0531 (4)
N4	0.1667 (3)	0.3358 (4)	0.95640 (18)	0.0800 (7)
O4	0.1477 (2)	0.4784 (3)	0.90715 (17)	0.0958 (7)
O5	0.0543 (3)	0.2366 (4)	0.9836 (3)	0.1476 (12)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0385 (10)	0.0368 (10)	0.0419 (10)	0.0019 (8)	−0.0053 (8)	−0.0154 (8)
C2	0.0370 (10)	0.0324 (10)	0.0394 (9)	−0.0006 (8)	−0.0006 (7)	−0.0105 (8)
C3	0.0416 (11)	0.0341 (10)	0.0432 (10)	−0.0005 (8)	−0.0042 (8)	−0.0140 (8)
C4	0.0424 (11)	0.0408 (11)	0.0404 (10)	0.0002 (8)	−0.0074 (8)	−0.0146 (9)
C5	0.0417 (11)	0.0354 (11)	0.0441 (10)	0.0013 (8)	−0.0072 (8)	−0.0130 (8)
C6	0.0423 (11)	0.0376 (11)	0.0425 (10)	−0.0002 (8)	−0.0053 (8)	−0.0131 (9)
C7	0.0720 (15)	0.0594 (14)	0.0481 (11)	−0.0071 (11)	−0.0169 (10)	−0.0227 (10)
C8	0.0756 (16)	0.0589 (15)	0.0743 (15)	−0.0113 (12)	−0.0163 (12)	−0.0322 (12)
C9	0.0711 (14)	0.0367 (11)	0.0512 (11)	−0.0104 (10)	−0.0162 (10)	−0.0074 (9)
C10	0.0547 (12)	0.0395 (12)	0.0390 (10)	−0.0004 (9)	−0.0093 (9)	−0.0130 (9)
C11	0.0591 (13)	0.0450 (12)	0.0383 (10)	−0.0033 (10)	−0.0112 (9)	−0.0149 (9)
C12	0.0527 (13)	0.0674 (14)	0.0428 (10)	0.0028 (11)	−0.0069 (9)	−0.0217 (10)
C13	0.0697 (16)	0.0748 (16)	0.0397 (11)	−0.0108 (13)	0.0027 (10)	−0.0105 (11)
C14	0.0813 (17)	0.0661 (15)	0.0391 (11)	0.0015 (13)	−0.0136 (11)	−0.0074 (10)
C15	0.0618 (15)	0.0741 (16)	0.0554 (13)	0.0050 (12)	−0.0206 (11)	−0.0128 (12)
C16	0.0514 (12)	0.0630 (14)	0.0502 (11)	−0.0086 (11)	−0.0118 (9)	−0.0109 (10)
N1	0.0500 (10)	0.0372 (9)	0.0434 (8)	−0.0004 (7)	−0.0106 (7)	−0.0122 (7)
N2	0.0650 (12)	0.0354 (10)	0.0452 (9)	−0.0090 (8)	−0.0114 (8)	−0.0098 (8)
N3	0.0888 (14)	0.0410 (11)	0.0522 (10)	−0.0149 (10)	−0.0131 (9)	−0.0123 (8)
O1	0.1016 (12)	0.0464 (9)	0.0463 (8)	−0.0109 (8)	−0.0231 (8)	−0.0073 (7)
O2	0.0730 (10)	0.0426 (8)	0.0482 (8)	−0.0033 (7)	−0.0205 (7)	−0.0175 (6)
O3	0.0704 (10)	0.0435 (8)	0.0447 (7)	−0.0063 (7)	−0.0205 (7)	−0.0119 (6)
N4	0.0603 (14)	0.109 (2)	0.0623 (13)	0.0128 (14)	−0.0020 (10)	−0.0218 (13)
O4	0.0948 (15)	0.1149 (17)	0.0783 (12)	0.0484 (13)	−0.0232 (10)	−0.0348 (12)
O5	0.0550 (14)	0.171 (3)	0.174 (3)	−0.0182 (16)	−0.0053 (14)	−0.010 (2)

Geometric parameters (Å, º) top

C1—C5	1.404 (2)	C9—H9A	0.9600
C1—C2	1.431 (2)	C9—H9B	0.9600
C1—C6	1.481 (2)	C9—H9C	0.9600
C2—N2	1.335 (2)	C10—N3	1.140 (2)
C2—C3	1.417 (2)	C11—C16	1.371 (3)
C3—C4	1.388 (2)	C11—C12	1.387 (3)
C3—C10	1.425 (3)	C11—O3	1.395 (2)
C4—N1	1.309 (2)	C12—C13	1.381 (3)
C4—O3	1.359 (2)	C12—N4	1.469 (3)
C5—N1	1.356 (2)	C13—C14	1.369 (3)
C5—C9	1.497 (3)	C13—H13	0.9300
C6—O1	1.215 (2)	C14—C15	1.368 (3)
C6—O2	1.318 (2)	C14—H14	0.9300
C7—O2	1.457 (2)	C15—C16	1.375 (3)
C7—C8	1.486 (3)	C15—H15	0.9300
C7—H7A	0.9700	C16—H16	0.9300
C7—H7B	0.9700	N2—H2A	0.86 (2)
C8—H8A	0.9600	N2—H2B	0.92 (2)
C8—H8B	0.9600	N4—O4	1.201 (3)
C8—H8C	0.9600	N4—O5	1.214 (3)

C5—C1—C2	118.42 (15)	H9A—C9—H9B	109.5
C5—C1—C6	124.14 (17)	C5—C9—H9C	109.5
C2—C1—C6	117.43 (15)	H9A—C9—H9C	109.5
N2—C2—C3	119.45 (16)	H9B—C9—H9C	109.5
N2—C2—C1	123.34 (16)	N3—C10—C3	176.00 (18)
C3—C2—C1	117.21 (15)	C16—C11—C12	118.77 (18)
C4—C3—C2	118.35 (16)	C16—C11—O3	116.93 (18)
C4—C3—C10	121.79 (16)	C12—C11—O3	124.21 (18)
C2—C3—C10	119.85 (16)	C13—C12—C11	120.4 (2)
N1—C4—O3	119.80 (16)	C13—C12—N4	118.3 (2)
N1—C4—C3	125.17 (16)	C11—C12—N4	121.4 (2)
O3—C4—C3	115.03 (16)	C14—C13—C12	120.0 (2)
N1—C5—C1	122.69 (17)	C14—C13—H13	120.0
N1—C5—C9	111.75 (15)	C12—C13—H13	120.0
C1—C5—C9	125.56 (16)	C15—C14—C13	119.6 (2)
O1—C6—O2	120.82 (16)	C15—C14—H14	120.2
O1—C6—C1	123.74 (17)	C13—C14—H14	120.2
O2—C6—C1	115.44 (15)	C14—C15—C16	120.7 (2)
O2—C7—C8	107.72 (16)	C14—C15—H15	119.7
O2—C7—H7A	110.2	C16—C15—H15	119.7
C8—C7—H7A	110.2	C11—C16—C15	120.5 (2)
O2—C7—H7B	110.2	C11—C16—H16	119.8
C8—C7—H7B	110.2	C15—C16—H16	119.8
H7A—C7—H7B	108.5	C4—N1—C5	118.08 (15)
C7—C8—H8A	109.5	C2—N2—H2A	120.3 (14)
C7—C8—H8B	109.5	C2—N2—H2B	114.6 (13)
H8A—C8—H8B	109.5	H2A—N2—H2B	125 (2)
C7—C8—H8C	109.5	C6—O2—C7	116.55 (14)
H8A—C8—H8C	109.5	C4—O3—C11	118.84 (15)
H8B—C8—H8C	109.5	O4—N4—O5	124.5 (3)
C5—C9—H9A	109.5	O4—N4—C12	119.0 (2)
C5—C9—H9B	109.5	O5—N4—C12	116.5 (2)

C5—C1—C2—N2	−178.52 (17)	O3—C11—C12—N4	1.1 (3)
C6—C1—C2—N2	2.4 (3)	C11—C12—C13—C14	2.2 (3)
C5—C1—C2—C3	1.8 (3)	N4—C12—C13—C14	−178.2 (2)
C6—C1—C2—C3	−177.30 (15)	C12—C13—C14—C15	−0.1 (3)
N2—C2—C3—C4	−179.08 (17)	C13—C14—C15—C16	−1.5 (4)
C1—C2—C3—C4	0.6 (3)	C12—C11—C16—C15	1.3 (3)
N2—C2—C3—C10	−0.3 (3)	O3—C11—C16—C15	178.09 (19)
C1—C2—C3—C10	179.41 (16)	C14—C15—C16—C11	0.8 (4)
C2—C3—C4—N1	−2.3 (3)	O3—C4—N1—C5	−178.43 (16)
C10—C3—C4—N1	178.96 (18)	C3—C4—N1—C5	1.2 (3)
C2—C3—C4—O3	177.40 (16)	C1—C5—N1—C4	1.5 (3)
C10—C3—C4—O3	−1.4 (3)	C9—C5—N1—C4	−178.27 (16)
C2—C1—C5—N1	−2.9 (3)	O1—C6—O2—C7	0.5 (3)
C6—C1—C5—N1	176.06 (16)	C1—C6—O2—C7	−178.49 (16)
C2—C1—C5—C9	176.76 (18)	C8—C7—O2—C6	−174.60 (17)
C6—C1—C5—C9	−4.2 (3)	N1—C4—O3—C11	0.3 (3)
C5—C1—C6—O1	176.23 (18)	C3—C4—O3—C11	−179.36 (16)
C2—C1—C6—O1	−4.8 (3)	C16—C11—O3—C4	118.4 (2)
C5—C1—C6—O2	−4.8 (3)	C12—C11—O3—C4	−64.9 (3)
C2—C1—C6—O2	174.18 (15)	C13—C12—N4—O4	150.4 (2)
C16—C11—C12—C13	−2.8 (3)	C11—C12—N4—O4	−30.0 (3)
O3—C11—C12—C13	−179.35 (17)	C13—C12—N4—O5	−30.2 (3)
C16—C11—C12—N4	177.6 (2)	C11—C12—N4—O5	149.4 (3)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C7—H7B···O4ⁱ	0.97	2.52	3.229 (3)	130
N2—H2A···N3ⁱⁱ	0.86 (2)	2.23 (2)	3.040 (3)	157.5 (19)
N2—H2B···O1	0.92 (2)	1.84 (2)	2.593 (2)	137.1 (18)
C7—H7B···Cg1ⁱ	0.97	2.92	3.716 (3)	140

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

Experimental details

Crystal data
Chemical formula	C₁₆H₁₄N₄O₅
M_r	342.31
Crystal system, space group	Triclinic, P1
Temperature (K)	294
a, b, c (Å)	7.9831 (6), 8.8661 (7), 12.2797 (10)
α, β, γ (°)	69.012 (1), 86.342 (1), 88.835 (1)
V (Å³)	809.83 (11)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	0.11
Crystal size (mm)	0.30 × 0.20 × 0.20

Data collection
Diffractometer	Bruker SMART APEX CCD area-detector
Absorption correction	–
No. of measured, independent and observed [I > 2σ(I)] reflections	8410, 3145, 2146
R_int	0.023
(sin θ/λ)_max (Å⁻¹)	0.617

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.049, 0.167, 1.07
No. of reflections	3145
No. of parameters	235
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.22, −0.20

Computer programs: SMART (Bruker, 2001), SAINT (Bruker, 2001), SHELXS97 (Sheldrick, 1997), SHELXL97 (Sheldrick, 1997), PLATON (Spek, 2003), SHELXTL (Sheldrick, 2001).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C7—H7B···O4ⁱ	0.97	2.52	3.229 (3)	130.3
N2—H2A···N3ⁱⁱ	0.86 (2)	2.23 (2)	3.040 (3)	157.5 (19)
N2—H2B···O1	0.92 (2)	1.84 (2)	2.593 (2)	137.1 (18)
C7—H7B···Cg1ⁱ	0.97	2.92	3.716 (3)	140

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

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