supplementary materials


Acta Cryst. (2007). E63, o3866    [ doi:10.1107/S160053680704038X ]

2-Amino-6-methylpyridinium 3-(4-hydroxy-3-methoxyphenyl)prop-2-enoate monohydrate

S.-F. Ni, W.-J. Feng, H. Guo and Z.-M. Jin

Abstract top

In the title salt, C6H9N2+·C10H9O4-·H2O, the cation, anion and solvent molecule are held together by N-H...O hydrogen bonds. A one-dimensional chiral chain along the c axis is formed by O-H...O hydrogen bonds. The chirality of the supramolecular chain-like arrangement is extended into layers parallel to the (101) plane by additional O-H...O hydrogen bonds. The structure is further stabilized by [pi]-[pi] interactions between benzene and pyridine rings [centroid-to-centroid distances = 3.813 (4) and 3.658 (3) Å].

Comment top

As reported, the synthesis and characterization of noncentrosymmetric supramolecular systems have attracted a great of interest in th past few years (Sarma et al., 1997; Thalladi et al., 1999; Kaminskii et al., 2006; Kiebacha et al., 2006; Kaminskii et al., 2007). Herein, we report a novel noncentrosymmetric crystal of the title complex (Fig. 3), (I), and discuss the structure (Table 1).

In the structure, 2-amino-6-methylpyridinium (AMP) and 3-(4-hydroxy-3-methoxyphenyl)-2-propenoate (ferulate) are linked through hydrogen bonding of N1—H1N···O4 and N2—H2B···O3 to produce an eight-membered hydrogen bonded ring system of R22(8) arrangement (Etter, 1990). This component shows an interaction with the water molecule by a N2—H2A···O5 hydrogen bond (Fig. 1 & Table 2). This is different from the componentially similar complex 2-amino-5-methylpyridinium ferulate monohydrate (Xuan et al., 2003), where the water molecule is incorporated with AMP by an O—H···O hydrogen bond.

Protonation of 2-aminopyridine always induces aminium-iminium tautomerism (Scheme 2) (Inuzuka & Fujimoto, 1986 and 1990). Obvious features of the iminium tautomer in (I) are revealed by the following bond length comparison. First, the N2—C1 [1.330 (3) Å] bond is slightly but significantly shorter than the N1—C1 [1.349 (3) Å] and N1—C5 [1.361 (3) Å] bonds (Table 1). Second, the C2—C3 [1.352 (4) Å] and C4—C5 [1.353 (4) Å] bonds are shorter than the C1—C2 [1.410 (3) Å] and C3—C4 [1.386 (4) Å] bonds. That means the imimium tautomer makes a great contribution to the structure. This situation is similiar to those observed in 2-amino-5-methylpyridinium ferulate (Xuan et al., 2003), 2-aminopyridinium acetate (Ishikawa et al., 2002), 2-amino-3-methylpyridinium maleate (Jin et al., 2002) and AMP neoabietate (Jin et al., 2000).

As shown in Fig. 2, one-dimensional C2 chains along the (101) direction are formed by O1—H1O···O3i hydrogen bonds. The presence of water molecules in the structure causes the following hydrogen bonds: N2—H2A···O5, O5—H5A···O1ii, O5—H5B···O4iii and C6—H6A···O5iv (Table 2). These chains link into chiral layers parallel to the (101) plane via the O5—H5B···O4iii hydrogen bonds. Neighbouring enantiomeric layers, which are mutual images on the plane of (101) are associated via the O5—H5A···O1ii hydrogen bonds. The whole noncentrosymmetric structure is stablized by ππ interactions between neighboring layers, with the relevant centroid···centroid separations between the pyridine and the benzene rings at (x, 1 − y, z + 1/2), 3.813 (4) Å and (x − 1/2, −y + 1/2, z − 1/2), 3.658 (3) Å.

Related literature top

For related literature, see: Etter (1990); Inuzuka & Fujimoto (1986, 1990); Ishikawa et al. (2002); Jin et al. (2000, 2002); Kaminskii et al. (2006, 2007); Kiebacha et al. (2006); Sarma et al. (1997); Thalladi et al. (1999); Xuan et al. (2003).

Experimental top

The title compound was synthesized from a mixture of 2-amino-6-methylpyridine (1 mmol, 0.11 g) and ferulic acid (1 mmol, 0.19 g). The mixture was dissolved in 10 ml water, then heated to 373 K and stirred for half an hour. After the reaction system was cooled to room temperature after five days the colorless crystals were collected.

Refinement top

H atoms attaching to N and O atoms were deduced from difference Fourier maps and incorporated in the refinement freely. Others were placed in calculated positions and allowed to ride on their parent atoms at distances of 0.93 Å for alkene and aromatic group and 0.96 Å for methyl, with isotropic displacement parameters 1.2 times Ueq of the parent atoms.

Computing details top

Data collection: XSCANS (Siemens, 1994); cell refinement: XSCANS; data reduction: SHELXTL (Bruker, 1998); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.

Figures top
[Figure 1] Fig. 1. The cell unit of (I) with atom labels, showing 40% probability displacement ellipsoids. The thin lines denote the hydrogen bonds.
[Figure 2] Fig. 2. The chiral hydrogen bond chain of (I) along the [101] direction. Hydrogen bonds are shown by thin lines, All H atoms are omitted for clarity. The superscripts, * and #, indicate the symmetry positions of (x + 1/2, − y + 3/2, z + 1/2) and (x − 1/2, − y + 1/2, z − 1/2), respectively.
[Figure 3] Fig. 3. The preparation of thetitle compound.
2-Amino-6-methylpyridinium 3-(4-hydroxy-3-methoxyphenyl)prop-2-enoate monohydrate top
Crystal data top
C6H9N2+·C10H9O4·H2OF(000) = 680
Mr = 320.34Dx = 1.337 Mg m3
Monoclinic, CcMo Kα radiation, λ = 0.71073 Å
Hall symbol: C -2ycCell parameters from 30 reflections
a = 11.266 (2) Åθ = 3.7–12.0°
b = 9.711 (1) ŵ = 0.10 mm1
c = 15.024 (2) ÅT = 296 K
β = 104.547 (8)°Block, colourless
V = 1591.0 (4) Å30.40 × 0.40 × 0.36 mm
Z = 4
Data collection top
Siemens P4
diffractometer
1571 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.012
graphiteθmax = 28.0°, θmin = 2.8°
ω scansh = 014
Absorption correction: empirical (using intensity measurements)
(SHELXTL; Bruker, 1998)
k = 012
Tmin = 0.955, Tmax = 0.960l = 1919
2235 measured reflections3 standard reflections every 97 reflections
1920 independent reflections intensity decay: 1.4%
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.033H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.075 w = 1/[σ2(Fo2) + (0.04P)2]
where P = (Fo2 + 2Fc2)/3
S = 0.98(Δ/σ)max < 0.001
1920 reflectionsΔρmax = 0.16 e Å3
234 parametersΔρmin = 0.13 e Å3
4 restraintsExtinction correction: SHELXL97 (Sheldrick, 1997), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.0225 (15)
Crystal data top
C6H9N2+·C10H9O4·H2OV = 1591.0 (4) Å3
Mr = 320.34Z = 4
Monoclinic, CcMo Kα radiation
a = 11.266 (2) ŵ = 0.10 mm1
b = 9.711 (1) ÅT = 296 K
c = 15.024 (2) Å0.40 × 0.40 × 0.36 mm
β = 104.547 (8)°
Data collection top
Siemens P4
diffractometer
1571 reflections with I > 2σ(I)
Absorption correction: empirical (using intensity measurements)
(SHELXTL; Bruker, 1998)
Rint = 0.012
Tmin = 0.955, Tmax = 0.960θmax = 28.0°
2235 measured reflections3 standard reflections every 97 reflections
1920 independent reflections intensity decay: 1.4%
Refinement top
R[F2 > 2σ(F2)] = 0.033H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.075Δρmax = 0.16 e Å3
S = 0.98Δρmin = 0.13 e Å3
1920 reflectionsAbsolute structure: ?
234 parametersFlack parameter: ?
4 restraintsRogers parameter: ?
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*/UeqOcc. (<1)
O10.63139 (17)0.81309 (17)0.79651 (11)0.0505 (5)
O20.55462 (15)0.56111 (16)0.80161 (10)0.0480 (5)
O30.21872 (16)0.43919 (16)0.29836 (10)0.0488 (4)
O40.29544 (17)0.24240 (15)0.36111 (11)0.0446 (4)
O50.0234 (2)0.3630 (3)0.04758 (14)0.0691 (6)
N10.26566 (16)0.09244 (19)0.20202 (13)0.0365 (4)
N20.1546 (2)0.2764 (2)0.12847 (16)0.0472 (5)
C10.2028 (2)0.1526 (2)0.12329 (15)0.0377 (5)
C20.1912 (2)0.0791 (3)0.04057 (16)0.0472 (6)
H20.14860.11680.01520.057*
C30.2429 (3)0.0470 (3)0.04365 (19)0.0556 (7)
H30.23640.09550.01070.067*
C40.3054 (3)0.1052 (3)0.1264 (2)0.0579 (7)
H40.34010.19220.12720.069*
C50.3159 (2)0.0355 (2)0.20598 (17)0.0450 (6)
C60.3764 (3)0.0885 (3)0.2995 (2)0.0630 (8)
H6A0.37210.01980.34460.076*0.50
H6B0.46070.10930.30290.076*0.50
H6C0.33520.17040.31140.076*0.50
H6D0.40650.17990.29470.076*0.50
H6E0.31800.09040.33640.076*0.50
H6F0.44340.02920.32790.076*0.50
C70.4530 (2)0.5648 (2)0.63826 (15)0.0355 (5)
H70.42470.47520.64040.043*
C80.5218 (2)0.6252 (2)0.71738 (14)0.0356 (5)
C90.56482 (19)0.7597 (2)0.71563 (14)0.0366 (5)
C100.5380 (2)0.8308 (2)0.63346 (15)0.0409 (5)
H100.56670.92020.63130.049*
C110.4682 (2)0.7693 (2)0.55374 (15)0.0386 (5)
H110.45020.81860.49890.046*
C120.42502 (19)0.6361 (2)0.55453 (14)0.0334 (5)
C130.3556 (2)0.5708 (2)0.46945 (13)0.0348 (5)
H130.31980.62930.42110.042*
C140.3384 (2)0.4371 (2)0.45420 (14)0.0416 (5)
H140.36650.37900.50430.050*
C150.2784 (2)0.3701 (2)0.36480 (14)0.0357 (5)
C160.5134 (2)0.4233 (2)0.80484 (16)0.0434 (5)
H16A0.42540.42140.78760.052*
H16B0.54270.38800.86610.052*
H16C0.54440.36760.76290.052*
H2A0.121 (2)0.316 (2)0.0782 (17)0.038 (7)*
H1N0.274 (2)0.135 (2)0.2531 (17)0.036 (6)*
H2B0.173 (2)0.318 (3)0.181 (2)0.055 (8)*
H1O0.659 (3)0.896 (3)0.7919 (19)0.058 (8)*
H5A0.061 (4)0.348 (5)0.087 (2)0.13 (2)*
H5B0.0448 (18)0.329 (4)0.069 (2)0.091 (13)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0690 (12)0.0358 (9)0.0363 (8)0.0158 (9)0.0058 (8)0.0049 (7)
O20.0680 (12)0.0397 (9)0.0286 (7)0.0130 (8)0.0022 (7)0.0024 (7)
O30.0656 (11)0.0393 (9)0.0310 (8)0.0093 (9)0.0077 (7)0.0041 (7)
O40.0623 (10)0.0338 (8)0.0308 (8)0.0009 (8)0.0011 (7)0.0031 (7)
O50.0660 (14)0.0864 (16)0.0450 (11)0.0116 (13)0.0045 (11)0.0133 (10)
N10.0411 (10)0.0338 (10)0.0331 (10)0.0021 (8)0.0064 (8)0.0079 (8)
N20.0603 (14)0.0447 (11)0.0302 (10)0.0074 (10)0.0007 (10)0.0028 (10)
C10.0381 (12)0.0400 (12)0.0331 (11)0.0055 (10)0.0054 (9)0.0052 (10)
C20.0497 (14)0.0563 (15)0.0344 (12)0.0096 (13)0.0082 (10)0.0123 (11)
C30.0592 (16)0.0570 (17)0.0514 (15)0.0077 (13)0.0152 (13)0.0268 (13)
C40.0633 (18)0.0416 (13)0.0672 (18)0.0029 (12)0.0137 (14)0.0182 (13)
C50.0450 (15)0.0340 (11)0.0523 (14)0.0024 (10)0.0054 (12)0.0078 (10)
C60.0729 (19)0.0411 (14)0.0640 (17)0.0115 (14)0.0035 (14)0.0022 (13)
C70.0441 (12)0.0287 (10)0.0307 (9)0.0034 (9)0.0038 (9)0.0033 (9)
C80.0432 (12)0.0327 (11)0.0283 (10)0.0004 (9)0.0041 (9)0.0005 (8)
C90.0411 (13)0.0308 (11)0.0338 (10)0.0014 (10)0.0016 (9)0.0053 (9)
C100.0530 (14)0.0256 (11)0.0394 (12)0.0011 (10)0.0031 (10)0.0001 (9)
C110.0505 (13)0.0321 (11)0.0291 (10)0.0057 (10)0.0025 (9)0.0035 (8)
C120.0379 (12)0.0305 (10)0.0297 (10)0.0046 (9)0.0047 (9)0.0031 (8)
C130.0419 (12)0.0344 (11)0.0238 (9)0.0045 (9)0.0004 (8)0.0012 (8)
C140.0559 (14)0.0391 (13)0.0248 (10)0.0011 (11)0.0008 (10)0.0005 (9)
C150.0441 (12)0.0346 (11)0.0253 (10)0.0012 (10)0.0028 (9)0.0020 (9)
C160.0550 (14)0.0403 (12)0.0338 (11)0.0027 (11)0.0091 (10)0.0045 (10)
Geometric parameters (Å, °) top
O1—C91.360 (2)C6—H6B0.9600
O1—H1O0.87 (3)C6—H6C0.9600
O2—C81.375 (3)C6—H6D0.9600
O2—C161.421 (2)C6—H6E0.9600
O3—C151.250 (3)C6—H6F0.9600
O4—C151.258 (3)C7—C81.376 (3)
O5—H5A0.819 (10)C7—C121.401 (3)
O5—H5B0.824 (10)C7—H70.9300
N1—C11.349 (3)C8—C91.396 (3)
N1—C51.361 (3)C9—C101.380 (3)
N1—H1N0.86 (2)C10—C111.392 (3)
N2—C11.330 (3)C10—H100.9300
N2—H2A0.85 (2)C11—C121.383 (3)
N2—H2B0.86 (3)C11—H110.9300
C1—C21.410 (3)C12—C131.465 (3)
C2—C31.352 (4)C13—C141.324 (3)
C2—H20.9300C13—H130.9300
C3—C41.386 (4)C14—C151.493 (3)
C3—H30.9300C14—H140.9300
C4—C51.353 (4)C16—H16A0.9600
C4—H40.9300C16—H16B0.9600
C5—C61.491 (4)C16—H16C0.9600
C6—H6A0.9600
C9—O1—H1O114.1 (19)C5—C6—H6F109.5
C8—O2—C16116.29 (16)H6A—C6—H6F56.3
H5A—O5—H5B105 (4)H6B—C6—H6F56.3
C1—N1—C5123.7 (2)H6C—C6—H6F141.1
C1—N1—H1N119.1 (16)H6D—C6—H6F109.5
C5—N1—H1N117.2 (16)H6E—C6—H6F109.5
C1—N2—H2A117.2 (16)C8—C7—C12121.08 (19)
C1—N2—H2B118.0 (18)C8—C7—H7119.5
H2A—N2—H2B123 (2)C12—C7—H7119.5
N2—C1—N1118.2 (2)O2—C8—C7124.40 (19)
N2—C1—C2124.1 (2)O2—C8—C9115.24 (18)
N1—C1—C2117.8 (2)C7—C8—C9120.35 (19)
C3—C2—C1119.0 (2)O1—C9—C10123.83 (19)
C3—C2—H2120.5O1—C9—C8117.13 (19)
C1—C2—H2120.5C10—C9—C8119.04 (19)
C2—C3—C4121.2 (2)C9—C10—C11120.3 (2)
C2—C3—H3119.4C9—C10—H10119.8
C4—C3—H3119.4C11—C10—H10119.8
C5—C4—C3120.1 (2)C12—C11—C10121.2 (2)
C5—C4—H4120.0C12—C11—H11119.4
C3—C4—H4120.0C10—C11—H11119.4
C4—C5—N1118.3 (2)C11—C12—C7118.00 (19)
C4—C5—C6125.4 (2)C11—C12—C13120.61 (19)
N1—C5—C6116.3 (2)C7—C12—C13121.36 (18)
C5—C6—H6A109.5C14—C13—C12126.75 (18)
C5—C6—H6B109.5C14—C13—H13116.6
H6A—C6—H6B109.5C12—C13—H13116.6
C5—C6—H6C109.5C13—C14—C15126.62 (19)
H6A—C6—H6C109.5C13—C14—H14116.7
H6B—C6—H6C109.5C15—C14—H14116.7
C5—C6—H6D109.5O3—C15—O4123.49 (19)
H6A—C6—H6D141.1O3—C15—C14121.05 (19)
H6B—C6—H6D56.3O4—C15—C14115.43 (19)
H6C—C6—H6D56.3O2—C16—H16A109.5
C5—C6—H6E109.5O2—C16—H16B109.5
H6A—C6—H6E56.3H16A—C16—H16B109.5
H6B—C6—H6E141.1O2—C16—H16C109.5
H6C—C6—H6E56.3H16A—C16—H16C109.5
H6D—C6—H6E109.5H16B—C16—H16C109.5
C5—N1—C1—N2177.9 (2)C7—C8—C9—O1179.5 (2)
C5—N1—C1—C21.3 (3)O2—C8—C9—C10178.8 (2)
N2—C1—C2—C3179.2 (2)C7—C8—C9—C100.3 (3)
N1—C1—C2—C30.0 (3)O1—C9—C10—C11179.4 (2)
C1—C2—C3—C40.8 (4)C8—C9—C10—C110.5 (3)
C2—C3—C4—C50.3 (4)C9—C10—C11—C120.5 (3)
C3—C4—C5—N11.0 (4)C10—C11—C12—C70.4 (3)
C3—C4—C5—C6177.5 (3)C10—C11—C12—C13177.7 (2)
C1—N1—C5—C41.8 (4)C8—C7—C12—C110.2 (3)
C1—N1—C5—C6176.8 (2)C8—C7—C12—C13177.8 (2)
C16—O2—C8—C70.1 (3)C11—C12—C13—C14159.9 (2)
C16—O2—C8—C9179.1 (2)C7—C12—C13—C1418.2 (3)
C12—C7—C8—O2178.9 (2)C12—C13—C14—C15173.4 (2)
C12—C7—C8—C90.2 (3)C13—C14—C15—O312.9 (4)
O2—C8—C9—O11.3 (3)C13—C14—C15—O4165.1 (2)
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
N1—H1N···O40.86 (2)1.89 (3)2.746 (2)175
N2—H2A···O50.85 (2)1.99 (2)2.815 (3)166
N2—H2B···O30.86 (2)2.08 (3)2.934 (4)173
O1—H1O···O3i0.87 (3)1.73 (3)2.596 (3)172
O5—H5A···O1ii0.82 (1)2.13 (1)2.938 (5)171
O5—H5B···O4iii0.82 (1)1.97 (1)2.785 (2)171
C6—H6A···O5iv0.962.543.302 (3)136
C13—H13···O1v0.932.523.332 (2)147
Symmetry codes: (i) x+1/2, −y+3/2, z+1/2; (ii) x−1/2, y−1/2, z−1; (iii) x−1/2, −y+1/2, z−1/2; (iv) x+1/2, −y+1/2, z+1/2; (v) x−1/2, −y+3/2, z−1/2.
Table 1
Hydrogen-bond geometry (Å, °)
top
D—H···AD—HH···AD···AD—H···A
N1—H1N···O40.86 (2)1.89 (3)2.746 (2)175
N2—H2A···O50.85 (2)1.99 (2)2.815 (3)166
N2—H2B···O30.86 (2)2.08 (3)2.934 (4)173
O1—H1O···O3i0.87 (3)1.73 (3)2.596 (3)172
O5—H5A···O1ii0.82 (1)2.13 (1)2.938 (5)171
O5—H5B···O4iii0.82 (1)1.97 (1)2.785 (2)171
C6—H6A···O5iv0.962.543.302 (3)136
C13—H13···O1v0.932.523.332 (2)147
Symmetry codes: (i) x+1/2, −y+3/2, z+1/2; (ii) x−1/2, y−1/2, z−1; (iii) x−1/2, −y+1/2, z−1/2; (iv) x+1/2, −y+1/2, z+1/2; (v) x−1/2, −y+3/2, z−1/2.
references
References top

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