4-Methyl­pyridinium 4-hy­droxy­benzoate

Abstract

In the crystal structure of the title salt, C₆H₈N⁺·C₇H₅O₃ ⁻, the anions and cations are linked by classical N—H⋯O hydrogen bonds. The anions are connected by pairs of C—H⋯O hydrogen bonds into inversion dimers and further linked by classical O—H⋯O hydrogen bonds. Weak π–π inter­actions [centroid–centroid distances = 3.740 (3) and 3.855 (3) Å] also occur. The dihedral angle between the CO₂ ⁻ group and the benzene ring to which it is attached is 20.95 (8)°.

Related literature  

For biological applications of picolinium-containing compounds, see: Butler & Walker (1993 ▶); Roy et al. (2001 ▶). For bond-length data, see: Allen et al. (1987 ▶).

Experimental  

Crystal data  

• C₆H₈N⁺·C₇H₅O₃ ⁻

• M _r = 231.24

• Monoclinic,

• a = 7.479 (5) Å

• b = 11.671 (4) Å

• c = 13.520 (5) Å

• β = 100.217 (5)°

• V = 1161.4 (10) ų

• Z = 4

• Mo Kα radiation

• μ = 0.10 mm⁻¹

• T = 295 K

• 0.24 × 0.20 × 0.18 mm

Data collection  

• Bruker Kappa APEXII CCD diffractometer

• Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ▶) T _min = 0.978, T _max = 0.983

• 11741 measured reflections

• 2564 independent reflections

• 1939 reflections with I > 2σ(I)

• R _int = 0.029

Refinement  

• R[F ² > 2σ(F ²)] = 0.043

• wR(F ²) = 0.128

• S = 1.06

• 2564 reflections

• 156 parameters

• H-atom parameters constrained

• Δρ_max = 0.38 e Å⁻³

• Δρ_min = −0.34 e Å⁻³

Data collection: APEX2 (Bruker, 2004 ▶); cell refinement: SAINT (Bruker, 2004 ▶); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: PLATON (Spek, 2009 ▶); software used to prepare material for publication: SHELXL97.

Supplementary Material

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Table 1. Hydrogen-bond geometry (Å, °).

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—H1⋯O2i	0.82	1.85	2.6707 (19)	176
N1—H1A⋯O3ii	0.86	1.73	2.5889 (19)	173
C2—H2⋯O1iii	0.93	2.60	3.485 (2)	160

Symmetry codes: (i) ; (ii) ; (iii) .

supplementary crystallographic information

Comment

Picolinium compounds are valuable intermediates in organic synthesis and they have been used widely in industrially important products and biologically active substrates as antitumor, antifungal, antibacterial, antineoplastic and antviral (Butler & Walker, 1993; Roy et al., 2001) activities.

The asymmetric unit of the title salt, I, (Fig. 1), contains C₆H₈N⁺ cation and C₇H₅O₃^- anion. The bond lengths and angles in both anion and cation are within normal range (Allen et al., 1987). The crystal structure exhibit weak intermolecular classical N—H···O, O—H···O and non–classical C—H···O interactions (Table 1 & Fig. 2). The π–π interactions are found in crystal structure: Cg1···Cg2^iv = 3.740 (3)Å; Cg1···Cg2^v = 3.855 (3)Å, where Cg1 and Cg2 are the centroids of the rings (C1–C6) and (N1/C8–C12), respectively. Symmetry codes: (iv) x, -y+1/2, z+1/2); (v) x+1, y, z;

Experimental

4-Picolinium 4-hydroxybenzoate compound was synthesized by using the starting materials of 4-picoline (1.66 g) and 4-hydroxybenzoic acid (1.12 g) in methanol and the single crystals suitable for X-ray diffraction were grown by slow evaporation.

Refinement

The H atoms were positioned geometrically with C—H = 0.93Å and 0.96Å, O—H = 0.82Å and N—H = 0.86Å, and allowed to ride on their parent atoms, with U_iso(H) = 1.5U_eq(O) for hydroxy group, U_iso(H) = 1.2U_eq(N) for amino group, U_iso(H) = 1.2U_eq(C) for aryl H and U_iso(H) = 1.5U_eq(C) for methyl H.

Figures

Fig. 1.

The molecular structure of title compound with the atom numbering scheme. Displacement ellipsoids are drawn at 30% probability level. H atoms are presented as a small spheres of arbitrary radius.

Fig. 2.

The crystal packing of I, viewed down a axis. Intermolecular hydrogen bonds are shown as dashed lines. H atoms not involved in hydrogen bonding have been omitted for clarity.

Crystal data

C6H8N+·C7H5O3−	F(000) = 488
Mr = 231.24	Dx = 1.322 Mg m−3
Monoclinic, P21/c	Melting point = 470.4–481.2 K
Hall symbol: -P 2ybc	Mo Kα radiation, λ = 0.71073 Å
a = 7.479 (5) Å	Cell parameters from 7082 reflections
b = 11.671 (4) Å	θ = 2.3–27.1°
c = 13.520 (5) Å	µ = 0.10 mm−1
β = 100.217 (5)°	T = 295 K
V = 1161.4 (10) Å3	Block, colourless
Z = 4	0.24 × 0.20 × 0.18 mm

Data collection

Bruker Kappa APEXII CCD diffractometer	2564 independent reflections
Radiation source: fine–focus sealed tube	1939 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.029
ω and φ scans	θmax = 27.2°, θmin = 2.3°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −9→9
Tmin = 0.978, Tmax = 0.983	k = −14→8
11741 measured reflections	l = −17→17

Refinement

Refinement on F2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.043	H-atom parameters constrained
wR(F2) = 0.128	w = 1/[σ2(Fo2) + (0.058P)2 + 0.3003P] where P = (Fo2 + 2Fc2)/3
S = 1.06	(Δ/σ)max < 0.001
2564 reflections	Δρmax = 0.38 e Å−3
156 parameters	Δρmin = −0.34 e Å−3
0 restraints	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.010 (2)

Special details

Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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 (Ų)

	x	y	z	Uiso*/Ueq
O1	0.55020 (18)	0.18454 (10)	0.02055 (8)	0.0578 (4)
H1	0.5981	0.2464	0.0131	0.087*
O2	0.7215 (2)	0.11967 (10)	0.49538 (9)	0.0599 (4)
O3	0.71511 (18)	−0.05893 (9)	0.44053 (8)	0.0563 (4)
C1	0.5832 (2)	0.15548 (13)	0.11952 (11)	0.0396 (4)
C2	0.5407 (2)	0.04549 (13)	0.14510 (11)	0.0435 (4)
H2	0.4883	−0.0056	0.0955	0.052*
C3	0.5761 (2)	0.01174 (12)	0.24435 (11)	0.0394 (4)
H3	0.5492	−0.0628	0.2612	0.047*
C4	0.6512 (2)	0.08716 (12)	0.31929 (10)	0.0356 (3)
C5	0.6894 (2)	0.19833 (12)	0.29287 (11)	0.0394 (4)
H5	0.7375	0.2503	0.3427	0.047*
C6	0.6571 (2)	0.23261 (13)	0.19390 (11)	0.0397 (4)
H6	0.6846	0.3070	0.1769	0.048*
C7	0.6972 (2)	0.05049 (13)	0.42610 (11)	0.0412 (4)
N1	0.18709 (19)	0.10699 (12)	0.37067 (10)	0.0475 (4)
H1A	0.2170	0.0966	0.4344	0.057*
C8	0.2266 (2)	0.20451 (14)	0.32853 (13)	0.0490 (4)
H8	0.2872	0.2617	0.3692	0.059*
C9	0.1813 (2)	0.22368 (14)	0.22732 (12)	0.0473 (4)
H9	0.2099	0.2933	0.2005	0.057*
C10	0.0932 (2)	0.13982 (14)	0.16510 (11)	0.0446 (4)
C11	0.0517 (2)	0.03949 (14)	0.20988 (13)	0.0480 (4)
H11	−0.0091	−0.0190	0.1709	0.058*
C12	0.1000 (2)	0.02581 (14)	0.31174 (13)	0.0478 (4)
H12	0.0710	−0.0424	0.3407	0.057*
C13	0.0475 (3)	0.15746 (19)	0.05391 (14)	0.0686 (6)
H13A	0.0259	0.2374	0.0398	0.103*
H13B	−0.0596	0.1145	0.0272	0.103*
H13C	0.1469	0.1318	0.0234	0.103*

Atomic displacement parameters (Ų)

	U11	U22	U33	U12	U13	U23
O1	0.0913 (9)	0.0446 (7)	0.0328 (6)	−0.0132 (6)	−0.0014 (6)	0.0060 (5)
O2	0.1019 (10)	0.0430 (7)	0.0334 (6)	0.0124 (6)	0.0079 (6)	−0.0037 (5)
O3	0.0980 (10)	0.0342 (6)	0.0363 (6)	0.0073 (6)	0.0106 (6)	0.0038 (5)
C1	0.0502 (9)	0.0365 (8)	0.0309 (7)	0.0008 (6)	0.0040 (6)	0.0032 (6)
C2	0.0561 (9)	0.0357 (8)	0.0363 (8)	−0.0062 (7)	0.0014 (7)	−0.0028 (6)
C3	0.0509 (9)	0.0283 (7)	0.0391 (8)	−0.0019 (6)	0.0081 (7)	0.0025 (6)
C4	0.0440 (8)	0.0316 (7)	0.0320 (7)	0.0046 (6)	0.0091 (6)	0.0012 (6)
C5	0.0520 (9)	0.0325 (8)	0.0339 (8)	−0.0003 (6)	0.0085 (6)	−0.0050 (6)
C6	0.0537 (9)	0.0282 (7)	0.0383 (8)	−0.0022 (6)	0.0106 (7)	0.0016 (6)
C7	0.0554 (9)	0.0357 (8)	0.0343 (8)	0.0052 (7)	0.0123 (7)	−0.0005 (6)
N1	0.0592 (9)	0.0506 (8)	0.0323 (7)	0.0066 (6)	0.0073 (6)	0.0070 (6)
C8	0.0561 (10)	0.0450 (9)	0.0441 (9)	−0.0015 (7)	0.0036 (7)	−0.0009 (7)
C9	0.0550 (10)	0.0417 (9)	0.0454 (9)	−0.0008 (7)	0.0089 (7)	0.0087 (7)
C10	0.0468 (9)	0.0502 (10)	0.0365 (8)	0.0059 (7)	0.0068 (7)	0.0045 (7)
C11	0.0544 (10)	0.0446 (9)	0.0440 (9)	−0.0011 (7)	0.0057 (7)	−0.0018 (7)
C12	0.0563 (10)	0.0415 (9)	0.0474 (9)	0.0016 (7)	0.0138 (8)	0.0070 (7)
C13	0.0898 (15)	0.0731 (13)	0.0400 (10)	0.0027 (11)	0.0039 (9)	0.0092 (9)

Geometric parameters (Å, º)

O1—C1	1.3599 (18)	N1—C8	1.329 (2)
O1—H1	0.8200	N1—C12	1.331 (2)
O2—C7	1.2255 (19)	N1—H1A	0.8600
O3—C7	1.2953 (19)	C8—C9	1.369 (2)
C1—C2	1.381 (2)	C8—H8	0.9300
C1—C6	1.389 (2)	C9—C10	1.379 (2)
C2—C3	1.378 (2)	C9—H9	0.9300
C2—H2	0.9300	C10—C11	1.379 (2)
C3—C4	1.384 (2)	C10—C13	1.496 (2)
C3—H3	0.9300	C11—C12	1.370 (2)
C4—C5	1.389 (2)	C11—H11	0.9300
C4—C7	1.487 (2)	C12—H12	0.9300
C5—C6	1.376 (2)	C13—H13A	0.9600
C5—H5	0.9300	C13—H13B	0.9600
C6—H6	0.9300	C13—H13C	0.9600
C1—O1—H1	109.5	C8—N1—H1A	120.8
O1—C1—C2	117.94 (13)	C12—N1—H1A	120.8
O1—C1—C6	122.02 (14)	N1—C8—C9	122.28 (16)
C2—C1—C6	120.05 (14)	N1—C8—H8	118.9
C3—C2—C1	119.75 (14)	C9—C8—H8	118.9
C3—C2—H2	120.1	C8—C9—C10	120.04 (15)
C1—C2—H2	120.1	C8—C9—H9	120.0
C2—C3—C4	120.93 (14)	C10—C9—H9	120.0
C2—C3—H3	119.5	C11—C10—C9	117.07 (15)
C4—C3—H3	119.5	C11—C10—C13	121.95 (16)
C3—C4—C5	118.77 (13)	C9—C10—C13	120.97 (16)
C3—C4—C7	121.46 (13)	C12—C11—C10	120.06 (16)
C5—C4—C7	119.74 (13)	C12—C11—H11	120.0
C6—C5—C4	120.85 (14)	C10—C11—H11	120.0
C6—C5—H5	119.6	N1—C12—C11	122.17 (15)
C4—C5—H5	119.6	N1—C12—H12	118.9
C5—C6—C1	119.62 (14)	C11—C12—H12	118.9
C5—C6—H6	120.2	C10—C13—H13A	109.5
C1—C6—H6	120.2	C10—C13—H13B	109.5
O2—C7—O3	122.48 (15)	H13A—C13—H13B	109.5
O2—C7—C4	122.01 (14)	C10—C13—H13C	109.5
O3—C7—C4	115.47 (13)	H13A—C13—H13C	109.5
C8—N1—C12	118.37 (14)	H13B—C13—H13C	109.5
O1—C1—C2—C3	178.41 (14)	C5—C4—C7—O2	20.1 (2)
C6—C1—C2—C3	−1.7 (2)	C3—C4—C7—O3	20.0 (2)
C1—C2—C3—C4	1.1 (2)	C5—C4—C7—O3	−157.84 (15)
C2—C3—C4—C5	0.4 (2)	C12—N1—C8—C9	−0.1 (2)
C2—C3—C4—C7	−177.46 (14)	N1—C8—C9—C10	−0.7 (3)
C3—C4—C5—C6	−1.4 (2)	C8—C9—C10—C11	1.2 (2)
C7—C4—C5—C6	176.54 (14)	C8—C9—C10—C13	−178.06 (16)
C4—C5—C6—C1	0.8 (2)	C9—C10—C11—C12	−0.9 (2)
O1—C1—C6—C5	−179.34 (14)	C13—C10—C11—C12	178.39 (17)
C2—C1—C6—C5	0.7 (2)	C8—N1—C12—C11	0.5 (2)
C3—C4—C7—O2	−162.01 (16)	C10—C11—C12—N1	0.0 (3)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1···O2i	0.82	1.85	2.6707 (19)	176
N1—H1A···O3ii	0.86	1.73	2.5889 (19)	173
C2—H2···O1iii	0.93	2.60	3.485 (2)	160

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