supplementary materials


lh5641 scheme

Acta Cryst. (2013). E69, o1500-o1501    [ doi:10.1107/S1600536813023891 ]

6-Methoxy-4-(2,4,5-trimethoxyphenyl)-2,2'-bipyridine-5-carbonitrile

S. Chantrapromma, T. Suwunwong, P. Ruanwas, C. K. Quah and H.-K. Fun

Abstract top

In the title 3-cyanopyridine derivative, C21H19N3O4, the 3-cyano-substituted pyridine ring forms dihedral angles of 2.35 (5) and 41.60 (5)° with the unsubstituted pyridine and 2,4,5-trimethoxy-substituted benzene rings, respectively. The dihedral angle between the unsubstituted pyridine and benzene rings is 39.84 (5)°. The methoxy groups form Cmethyl-O-C-(C,N) torsion angles in the range 0.80 (15)-11.45 (15)°. In the crystal, molecules related by 21 screw axes are linked by weak C-H...N hydrogen bonds along [010]. In addition, weak C-H...[pi] interactions and [pi]-[pi] stacking interactions between pyridine rings, with a centroid-centroid distance of 3.6448 (6) Å, are observed.

Comment top

3-Cyanopyridine derivatives have been reported for their wide range of applications such as in antimicrobial, analgesic, anti-hyperglycemic, antiproliferative and antitumor activities (Brandt et al., 2010; El-Sayed et al., 2011; Ji et al., 2007; Kim et al., 2005), as well as in usage as fluorescence materials (Koner et al., 2012). There are several methods to synthesize substituted 3-cyanopyridine derivatives including by condensation of α,β-unsaturated ketones and malononitrile (Al-Jaber et al., 2012; Zhou et al., 2006). Our research is aimed at the synthesis and preliminary fluorescent and antibacterial screening of the 3-cyanopyridine derivatives. The title compound (I) was synthesized and was found to exhibit fluorescence property which will be reported elsewhere together with the other related compounds. Herein the crystal structure of (I) was reported.

The title compound (I), C21H19N3O4 is a non-planar molecule (Fig. 1) in which the 3-cyano-substituted pyridine ring is approximately co-planar with the unsubstituted pyridine ring and inclined to the 2,4,5-trimethoxy-substituted ring with dihedral angles of 2.35 (5) and 41.60 (5)°, respectively. The dihedral angle between the unsubstituted pyridine and benzene rings is 39.84 (5)°. For the 2,4,5-trimethoxyphenyl moiety, the two substituted methoxy groups at ortho and meta positions are slightly twisted with the attached benzene ring with torsion angles C19–O2–C12–C13 = -11.45 (15)° and C21–O4–C15–C16 = -8.11 (16)° whereas the para methoxy group is essentially co-planar with a dihedral angle of C20–O3–C14–C13 = -0.80 (15)°. In addition, the methoxy group of the 3-cyanopyridine group is also essentially co-planar with the pyridine ring as indicated by the torsion angle C17–O1–C10–N2 = 6.18 (14)°. The bond distances agree with the literature values (Allen et al., 1987) and are comparable with those found in the related structures (Chantrapromma et al., 2010; Suwunwong et al., 2012).

In the crystal (Fig. 2), molecules related by 21 screw axes are linked by weak C—H···N interactions (Table 1) to form helical chains. The crystal is further stabilized by weak C—H···π interactions (Table 1) and ππ interaction with the Cg1···Cg2iii distance of 3.6448 (6) Å (iii = -x, 1 - y, -z); Cg1 and Cg2 are the centroids of N1/C1–C5 and N2/C6–C10 pyridine rings, respectively.

Related literature top

For the synthesis and applications of 3-cyanopyridine derivatives, see: Al-Jaber et al. (2012); Brandt et al. (2010); El-Sayed et al. (2011); Ji et al. (2007); Kim et al. (2005); Koner et al. (2012); Suwunwong et al. (2011); Zhou et al. (2006). For related structures, see: Chantrapromma et al. (2010); Suwunwong et al. (2012). For standard bond-length data, see: Allen et al. (1987).

Experimental top

The title compound (I) was synthesized by stirring a solution of (E)-1-(pyridin-2-yl)-3-(2,4,5-trimethoxyphenyl)prop-2-en-1-one (Suwunwong et al., 2011) (0.30 g, 1 mmol) in 10 ml of methanol with a freshly prepared sodium methoxide (1 mmol of sodium in 20 ml of methanol). Excess malononitrile (0.13 g, 2 mmol) was then added with continuous stirring at room temperature until the precipitate was separated out. The resulting solid was filtered and washed with hexane. Colorless block-shaped single crystals of the title compound suitable for x-ray structure determination were recrystallized from ethanol/methanol (1:1 v/v) by the slow evaporation of the solvent at room temperature after several days, Mp. 506–507 K.

Refinement top

All H atoms were positioned geometrically and allowed to ride on their parent atoms, with d(C—H) = 0.95 Å for aromatic and 0.98 Å for CH3 atoms. The Uiso values were constrained to be 1.5Ueq of the carrier atom for methyl H atoms and 1.2Ueq for the remaining H atoms. A rotating group model was used for the methyl groups.

Computing details top

Data collection: APEX2 (Bruker, 2005); cell refinement: SAINT (Bruker, 2005); data reduction: SAINT (Bruker, 2005); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008), PLATON (Spek, 2009), Mercury (Macrae et al., 2006) and publCIF (Westrip, 2010).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound, showing 50% probability displacement ellipsoids.
[Figure 2] Fig. 2. The crystal packing of the title compound viewed approximately along the a axis. Weak C—H···N interactions are shown as dashed lines. For clarity, only H atoms involved in hydrogen bonds are shown.
6-Methoxy-4-(2,4,5-trimethoxyphenyl)-2,2'-bipyridine-5-carbonitrile top
Crystal data top
C21H19N3O4F(000) = 792
Mr = 377.39Dx = 1.407 Mg m3
Monoclinic, P21/cMelting point = 506–507 K
Hall symbol: -P 2ybcMo Kα radiation, λ = 0.71073 Å
a = 14.9967 (3) ÅCell parameters from 5182 reflections
b = 7.4039 (2) Åθ = 2.4–30.0°
c = 17.5795 (4) ŵ = 0.10 mm1
β = 114.080 (1)°T = 100 K
V = 1782.06 (7) Å3Block, colorless
Z = 40.60 × 0.29 × 0.23 mm
Data collection top
Bruker APEXII CCD area-detector
diffractometer
5182 independent reflections
Radiation source: sealed tube4386 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.030
φ and ω scansθmax = 30.0°, θmin = 2.4°
Absorption correction: multi-scan
(SADABS; Bruker, 2005)
h = 2121
Tmin = 0.943, Tmax = 0.977k = 1010
20323 measured reflectionsl = 2224
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)] = 0.042Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.116H-atom parameters constrained
S = 1.03 w = 1/[σ2(Fo2) + (0.0629P)2 + 0.5246P]
where P = (Fo2 + 2Fc2)/3
5182 reflections(Δ/σ)max = 0.001
257 parametersΔρmax = 0.40 e Å3
0 restraintsΔρmin = 0.31 e Å3
Crystal data top
C21H19N3O4V = 1782.06 (7) Å3
Mr = 377.39Z = 4
Monoclinic, P21/cMo Kα radiation
a = 14.9967 (3) ŵ = 0.10 mm1
b = 7.4039 (2) ÅT = 100 K
c = 17.5795 (4) Å0.60 × 0.29 × 0.23 mm
β = 114.080 (1)°
Data collection top
Bruker APEXII CCD area-detector
diffractometer
5182 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2005)
4386 reflections with I > 2σ(I)
Tmin = 0.943, Tmax = 0.977Rint = 0.030
20323 measured reflectionsθmax = 30.0°
Refinement top
R[F2 > 2σ(F2)] = 0.042H-atom parameters constrained
wR(F2) = 0.116Δρmax = 0.40 e Å3
S = 1.03Δρmin = 0.31 e Å3
5182 reflectionsAbsolute structure: ?
257 parametersAbsolute structure parameter: ?
0 restraintsRogers parameter: ?
Special details top

Experimental. The crystal was placed in the cold stream of an Oxford Cryosystems Cobra open-flow nitrogen cryostat (Cosier & Glazer, 1986) operating at 100.0 (1) K.

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
O10.08878 (6)0.11337 (11)0.09750 (5)0.01663 (17)
O20.21018 (6)0.46941 (10)0.24541 (5)0.01852 (17)
O30.48961 (5)0.12019 (10)0.42643 (5)0.01676 (17)
O40.44854 (6)0.13384 (11)0.31664 (5)0.02014 (18)
N10.10990 (7)0.40828 (13)0.10405 (6)0.01619 (19)
N20.00502 (6)0.22953 (12)0.03257 (5)0.01373 (18)
N30.32255 (7)0.04540 (15)0.03661 (7)0.0231 (2)
C10.19408 (8)0.48087 (15)0.09883 (7)0.0174 (2)
H1A0.19820.51910.14890.021*
C20.27560 (8)0.50345 (15)0.02446 (7)0.0176 (2)
H2A0.33400.55430.02390.021*
C30.26961 (8)0.44990 (16)0.04895 (7)0.0187 (2)
H3A0.32400.46400.10090.022*
C40.18290 (8)0.37531 (15)0.04529 (7)0.0160 (2)
H4A0.17680.33810.09470.019*
C50.10496 (7)0.35617 (13)0.03249 (6)0.01291 (19)
C60.01002 (7)0.27984 (13)0.03969 (6)0.01266 (19)
C70.06802 (7)0.26430 (14)0.11670 (6)0.0139 (2)
H7A0.06050.29910.16580.017*
C80.15792 (7)0.19739 (13)0.12237 (6)0.01287 (19)
C90.16324 (7)0.14605 (14)0.04744 (6)0.01298 (19)
C100.07884 (7)0.16495 (14)0.02772 (6)0.01309 (19)
C110.24309 (7)0.18194 (14)0.20364 (6)0.01303 (19)
C120.26734 (7)0.31794 (14)0.26440 (6)0.0139 (2)
C130.34940 (7)0.30003 (14)0.33993 (6)0.0140 (2)
H13A0.36480.39250.38080.017*
C140.40836 (7)0.14785 (14)0.35544 (6)0.01330 (19)
C150.38513 (7)0.00954 (14)0.29540 (7)0.0144 (2)
C160.30335 (7)0.02751 (14)0.22149 (6)0.01395 (19)
H16A0.28720.06690.18150.017*
C170.00747 (8)0.15056 (17)0.17547 (7)0.0197 (2)
H17A0.02230.10650.22160.030*
H17B0.00420.28110.18130.030*
H17C0.05100.08940.17660.030*
C180.25207 (8)0.08862 (14)0.04235 (7)0.0156 (2)
C190.22509 (8)0.59686 (15)0.31086 (7)0.0179 (2)
H19A0.17540.69190.29050.027*
H19B0.29010.65080.32860.027*
H19C0.21990.53500.35820.027*
C200.51581 (8)0.25983 (15)0.48834 (7)0.0176 (2)
H20A0.57480.22400.53660.026*
H20B0.46220.27860.50570.026*
H20C0.52840.37220.46490.026*
C210.43561 (9)0.26391 (16)0.25325 (8)0.0222 (2)
H21A0.48840.35310.27400.033*
H21B0.43690.20320.20420.033*
H21C0.37270.32490.23800.033*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0182 (4)0.0217 (4)0.0112 (3)0.0019 (3)0.0073 (3)0.0016 (3)
O20.0206 (4)0.0147 (4)0.0154 (4)0.0058 (3)0.0025 (3)0.0031 (3)
O30.0152 (3)0.0164 (4)0.0146 (4)0.0022 (3)0.0019 (3)0.0016 (3)
O40.0214 (4)0.0175 (4)0.0186 (4)0.0082 (3)0.0052 (3)0.0020 (3)
N10.0170 (4)0.0174 (4)0.0164 (4)0.0018 (3)0.0091 (3)0.0008 (3)
N20.0147 (4)0.0135 (4)0.0135 (4)0.0011 (3)0.0063 (3)0.0006 (3)
N30.0234 (5)0.0244 (5)0.0266 (5)0.0047 (4)0.0154 (4)0.0035 (4)
C10.0202 (5)0.0171 (5)0.0187 (5)0.0027 (4)0.0119 (4)0.0012 (4)
C20.0152 (5)0.0150 (5)0.0248 (6)0.0012 (4)0.0104 (4)0.0006 (4)
C30.0143 (4)0.0197 (5)0.0196 (5)0.0000 (4)0.0043 (4)0.0017 (4)
C40.0160 (4)0.0168 (5)0.0152 (5)0.0007 (4)0.0062 (4)0.0025 (4)
C50.0141 (4)0.0111 (4)0.0153 (5)0.0013 (3)0.0077 (4)0.0000 (3)
C60.0142 (4)0.0110 (4)0.0144 (5)0.0008 (3)0.0075 (4)0.0004 (3)
C70.0150 (4)0.0148 (4)0.0135 (5)0.0001 (4)0.0074 (4)0.0011 (3)
C80.0141 (4)0.0120 (4)0.0129 (4)0.0006 (3)0.0059 (4)0.0001 (3)
C90.0139 (4)0.0122 (4)0.0142 (5)0.0003 (3)0.0072 (4)0.0002 (3)
C100.0167 (4)0.0119 (4)0.0120 (4)0.0006 (3)0.0073 (4)0.0005 (3)
C110.0128 (4)0.0144 (5)0.0125 (4)0.0001 (3)0.0058 (3)0.0000 (3)
C120.0140 (4)0.0135 (5)0.0146 (5)0.0013 (4)0.0061 (4)0.0005 (4)
C130.0152 (4)0.0136 (5)0.0134 (5)0.0001 (4)0.0059 (4)0.0011 (4)
C140.0123 (4)0.0152 (5)0.0124 (4)0.0005 (3)0.0051 (4)0.0014 (3)
C150.0151 (4)0.0130 (5)0.0167 (5)0.0022 (4)0.0083 (4)0.0010 (4)
C160.0158 (4)0.0136 (5)0.0135 (5)0.0004 (4)0.0071 (4)0.0016 (4)
C170.0215 (5)0.0256 (6)0.0107 (5)0.0002 (4)0.0051 (4)0.0000 (4)
C180.0183 (5)0.0152 (5)0.0143 (5)0.0003 (4)0.0078 (4)0.0011 (4)
C190.0188 (5)0.0158 (5)0.0172 (5)0.0028 (4)0.0055 (4)0.0041 (4)
C200.0156 (5)0.0177 (5)0.0162 (5)0.0018 (4)0.0030 (4)0.0029 (4)
C210.0273 (6)0.0188 (5)0.0225 (6)0.0059 (4)0.0122 (5)0.0033 (4)
Geometric parameters (Å, º) top
O1—C101.3499 (12)C8—C91.4041 (14)
O1—C171.4415 (13)C8—C111.4820 (13)
O2—C121.3676 (12)C9—C101.4152 (13)
O2—C191.4332 (13)C9—C181.4355 (14)
O3—C141.3576 (12)C11—C121.4036 (14)
O3—C201.4349 (13)C11—C161.4110 (14)
O4—C151.3715 (12)C12—C131.4006 (14)
O4—C211.4250 (14)C13—C141.3888 (14)
N1—C11.3403 (14)C13—H13A0.9500
N1—C51.3465 (13)C14—C151.4085 (14)
N2—C101.3152 (13)C15—C161.3819 (14)
N2—C61.3549 (13)C16—H16A0.9500
N3—C181.1476 (14)C17—H17A0.9800
C1—C21.3883 (15)C17—H17B0.9800
C1—H1A0.9500C17—H17C0.9800
C2—C31.3876 (16)C19—H19A0.9800
C2—H2A0.9500C19—H19B0.9800
C3—C41.3899 (15)C19—H19C0.9800
C3—H3A0.9500C20—H20A0.9800
C4—C51.3970 (14)C20—H20B0.9800
C4—H4A0.9500C20—H20C0.9800
C5—C61.4885 (14)C21—H21A0.9800
C6—C71.3866 (14)C21—H21B0.9800
C7—C81.4013 (14)C21—H21C0.9800
C7—H7A0.9500
C10—O1—C17116.48 (8)O2—C12—C11117.43 (9)
C12—O2—C19117.84 (8)C13—C12—C11120.54 (9)
C14—O3—C20116.99 (8)C14—C13—C12120.38 (9)
C15—O4—C21116.88 (8)C14—C13—H13A119.8
C1—N1—C5117.40 (9)C12—C13—H13A119.8
C10—N2—C6117.15 (9)O3—C14—C13124.30 (9)
N1—C1—C2123.76 (10)O3—C14—C15115.72 (9)
N1—C1—H1A118.1C13—C14—C15119.98 (9)
C2—C1—H1A118.1O4—C15—C16125.54 (9)
C3—C2—C1118.37 (10)O4—C15—C14115.26 (9)
C3—C2—H2A120.8C16—C15—C14119.20 (9)
C1—C2—H2A120.8C15—C16—C11121.96 (9)
C2—C3—C4119.00 (10)C15—C16—H16A119.0
C2—C3—H3A120.5C11—C16—H16A119.0
C4—C3—H3A120.5O1—C17—H17A109.5
C3—C4—C5118.62 (10)O1—C17—H17B109.5
C3—C4—H4A120.7H17A—C17—H17B109.5
C5—C4—H4A120.7O1—C17—H17C109.5
N1—C5—C4122.85 (9)H17A—C17—H17C109.5
N1—C5—C6116.40 (9)H17B—C17—H17C109.5
C4—C5—C6120.73 (9)N3—C18—C9178.32 (12)
N2—C6—C7123.03 (9)O2—C19—H19A109.5
N2—C6—C5116.20 (9)O2—C19—H19B109.5
C7—C6—C5120.77 (9)H19A—C19—H19B109.5
C6—C7—C8120.21 (9)O2—C19—H19C109.5
C6—C7—H7A119.9H19A—C19—H19C109.5
C8—C7—H7A119.9H19B—C19—H19C109.5
C7—C8—C9116.76 (9)O3—C20—H20A109.5
C7—C8—C11121.44 (9)O3—C20—H20B109.5
C9—C8—C11121.80 (9)H20A—C20—H20B109.5
C8—C9—C10118.53 (9)O3—C20—H20C109.5
C8—C9—C18123.23 (9)H20A—C20—H20C109.5
C10—C9—C18118.06 (9)H20B—C20—H20C109.5
N2—C10—O1120.08 (9)O4—C21—H21A109.5
N2—C10—C9124.32 (9)O4—C21—H21B109.5
O1—C10—C9115.60 (9)H21A—C21—H21B109.5
C12—C11—C16117.94 (9)O4—C21—H21C109.5
C12—C11—C8122.14 (9)H21A—C21—H21C109.5
C16—C11—C8119.92 (9)H21B—C21—H21C109.5
O2—C12—C13121.99 (9)
C5—N1—C1—C20.52 (16)C8—C9—C10—O1179.95 (9)
N1—C1—C2—C30.76 (17)C18—C9—C10—O14.76 (14)
C1—C2—C3—C40.29 (16)C7—C8—C11—C1242.34 (15)
C2—C3—C4—C50.33 (16)C9—C8—C11—C12137.61 (11)
C1—N1—C5—C40.16 (15)C7—C8—C11—C16138.34 (10)
C1—N1—C5—C6178.65 (9)C9—C8—C11—C1641.70 (14)
C3—C4—C5—N10.58 (16)C19—O2—C12—C1311.45 (15)
C3—C4—C5—C6179.01 (10)C19—O2—C12—C11171.00 (9)
C10—N2—C6—C70.63 (15)C16—C11—C12—O2178.04 (9)
C10—N2—C6—C5178.74 (9)C8—C11—C12—O21.29 (15)
N1—C5—C6—N2179.26 (9)C16—C11—C12—C130.46 (15)
C4—C5—C6—N20.74 (14)C8—C11—C12—C13178.87 (9)
N1—C5—C6—C70.12 (14)O2—C12—C13—C14176.97 (10)
C4—C5—C6—C7178.65 (10)C11—C12—C13—C140.50 (16)
N2—C6—C7—C81.31 (16)C20—O3—C14—C130.80 (15)
C5—C6—C7—C8178.03 (9)C20—O3—C14—C15179.26 (9)
C6—C7—C8—C90.94 (15)C12—C13—C14—O3179.36 (10)
C6—C7—C8—C11179.02 (9)C12—C13—C14—C150.70 (16)
C7—C8—C9—C100.02 (14)C21—O4—C15—C168.11 (16)
C11—C8—C9—C10179.94 (9)C21—O4—C15—C14171.38 (10)
C7—C8—C9—C18174.95 (9)O3—C14—C15—O40.60 (14)
C11—C8—C9—C185.01 (16)C13—C14—C15—O4179.45 (9)
C6—N2—C10—O1179.62 (9)O3—C14—C15—C16179.88 (9)
C6—N2—C10—C90.37 (15)C13—C14—C15—C160.07 (15)
C17—O1—C10—N26.18 (14)O4—C15—C16—C11178.40 (10)
C17—O1—C10—C9173.13 (9)C14—C15—C16—C111.06 (16)
C8—C9—C10—N20.67 (16)C12—C11—C16—C151.25 (15)
C18—C9—C10—N2174.53 (10)C8—C11—C16—C15178.09 (10)
Hydrogen-bond geometry (Å, º) top
Cg3 is the centroid of the C11–C16 ring.
D—H···AD—HH···AD···AD—H···A
C20—H20C···N3i0.982.593.3774 (17)138
C1—H1A···Cg3ii0.952.893.7062 (13)145
Symmetry codes: (i) x+1, y+1/2, z+1/2; (ii) x, y+1/2, z+1/2.
Hydrogen-bond geometry (Å, º) top
Cg3 is the centroid of the C11–C16 ring.
D—H···AD—HH···AD···AD—H···A
C20—H20C···N3i0.982.593.3774 (17)138
C1—H1A···Cg3ii0.952.893.7062 (13)145
Symmetry codes: (i) x+1, y+1/2, z+1/2; (ii) x, y+1/2, z+1/2.
Acknowledgements top

TS and SC thank the Thailand Research Fund through the Royal Golden Jubilee PhD Program (grant No. PHD/0257/2553) for financial support. The authors thank the Universiti Sains Malaysia for the APEX DE2012 grant No. 1002/PFIZIK/910323.

references
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