Crystal structure of 4-amino­benzoic acid–4-methyl­pyridine (1/1)

M Krishna Kumar; P Pandi; S Sudhahar; G Chakkaravarthi; R Mohan Kumar

doi:10.1107/S2056989015000791

. 2015 Jan 21;71(Pt 2):o125–o126. doi: 10.1107/S2056989015000791

Crystal structure of 4-aminobenzoic acid–4-methylpyridine (1/1)

M Krishna Kumar ^a, P Pandi ^b, S Sudhahar ^a, G Chakkaravarthi ^c,^*, R Mohan Kumar ^a,^*

PMCID: PMC4384565 PMID: 25878865

Abstract

In the title 1:1 adduct, C₆H₇N·C₇H₇NO₂, the carboxylic acid group is twisted at an angle of 4.32 (18)° with respect to the attached benzene ring. In the crystal, the carboxylic acid group is linked to the pyridine ring by an O—H⋯N hydrogen bond, forming a dimer. The dimers are linked by N—H⋯O hydrogen bonds, generating (010) sheets.

Keywords: crystal structure, adduct, O—H⋯N and N—H⋯O hydrogen bonds, layered structure

Related literature

For background to pyridine derivatives, see: Tomaru et al. (1991 ▸). Katritzky et al. (1996 ▸); Akkurt et al. (2005 ▸). For related structures, see: Smith & Wermuth (2010 ▸); Hemamalini & Fun (2010 ▸); Kannan et al. (2012 ▸); Thanigaimani et al. (2012 ▸); Muralidharan et al. (2013 ▸).

Experimental

Crystal data

C₆H₇N·C₇H₇NO₂
M _r = 230.26
Monoclinic,
a = 7.5970 (7) Å
b = 11.6665 (12) Å
c = 7.6754 (8) Å
β = 114.200 (3)°
V = 620.49 (11) Å³
Z = 2
Mo Kα radiation
μ = 0.09 mm⁻¹
T = 295 K
0.28 × 0.24 × 0.20 mm

Data collection

Bruker Kappa APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ▸) T _min = 0.977, T _max = 0.983
10064 measured reflections
2144 independent reflections
1458 reflections with I > 2σ(I)
R _int = 0.030

Refinement

R[F ² > 2σ(F ²)] = 0.038
wR(F ²) = 0.108
S = 1.03
2144 reflections
159 parameters
3 restraints
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.12 e Å⁻³
Δρ_min = −0.13 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, 2015 ▸); molecular graphics: PLATON (Spek, 2009 ▸); software used to prepare material for publication: SHELXL97.

Supplementary Material

Crystal structure: contains datablock(s) global, I. DOI: 10.1107/S2056989015000791/hb7348sup1.cif

e-71-0o125-sup1.cif^{(21.7KB, cif)}

Structure factors: contains datablock(s) I. DOI: 10.1107/S2056989015000791/hb7348Isup2.hkl

e-71-0o125-Isup2.hkl^{(103.2KB, hkl)}

Click here for additional data file.^{(1.5MB, tif)}

. DOI: 10.1107/S2056989015000791/hb7348fig1.tif

The molecular structure of (I), with 30% probability displacement ellipsoids for non-H atoms.

CCDC reference: 1043592

Additional supporting information: crystallographic information; 3D view; checkCIF report

Table 1. Hydrogen-bond geometry (, ).

DHA	DH	HA	D A	DHA
O1H1N2ⁱ	0.84(1)	1.81(1)	2.644(3)	177(4)
N1H1AO2ⁱⁱ	0.86	2.32	3.049(3)	142
N1H1BO2ⁱⁱⁱ	0.86	2.17	3.031(3)	174

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

Acknowledgments

The authors wish to acknowledge the SAIF, IIT, Madras, for the data collection.

supplementary crystallographic information

S1. Chemical context

Aminopyridine and its derivatives play an important role in heterocyclic chemistry (Katritzky et al., 1996). Some pyridine derivatives possess nonlinear optical (NLO) properties (Tomaru et al., 1991) and possess antibacterial and antifungal activities (Akkurt et al., 2005). we herewith, report the synthesis and the crystal structure of (I) (Fig. 1).

S2. Structural commentary

The molecular structure of the title compound (I) is shown in (Fig. 1). It consists of two independent molecules in the assymetric unit. In the 4-aminobenzoic acid molecule, the carboxyl group is twisted at an angle of 4.32 (18)° with respect to the aromatic ring. In the 4-methylpyridine molecule, the pyridine ring (C8—C12/N2) is almost planar [maximum deviation 0.002 (3) Å]. The dihedral angle between the benzene ring (C1—C6) and pyridine ring (C8—C12/N2) is 57.11 (14)°.

S3. Supramolecular features

In the crystal structure, 4-aminobenzoate and 4-methylpyridine molecules are linked by weak intermolecular O—H···N hydrogen bonds and forms infinite one-dimensional chain along [0 0 1]. The adjacent 4-aminobenzoate molecules are connected by weak intermolecular N—H···O hydrogen bonds, forming R²₂(12) ring motif in a two-dimensional network in the (010) plane (Table 2 & Fig. 2).

S4. Database survey

Several similar structures containing methylpyridinium and nitrobenzoate molecules have been reported earlier: i.e., 2-Amino-5-methylpyridinium 2-aminobenzoate (Thanigaimani et al., 2012); 2-Amino-5-chloropyridinium 4-aminobenzoate (Kannan et al., 2012); 2-Amino-4-methylpyridinium 2-nitrobenzoate (Muralidharan et al., 2013); 4-Methylpyridinium 2-carboxy-4,5-dichlorobenzoate monohydrate [Smith & Wermuth, (2010)]; 2-Amino-4-methylpyridinium 2-hydroxybenzoate [Hemamalini & Fun (2010)].

S5. Synthesis and crystallization

Equimolar quantity of 4-methylpyridine and 4-aminobenzoic acid were dissolved in methanol-water mixed solvent and colourless blocks of the title adduct were grown by slow evaporation of the solvents.

S6. Refinement

Crystal data, data collection and structure refinement details are summarized in Table 1. The hydrogen atoms attached to C atoms and N atom were fixed geometrically and treated as riding with C—H = 0.93 Å (aromatic) or 0.96 Å (methyl) and N—H = 0.86 Å with Uiso(H) = 1.2 Ueq(C or N) or 1.5 Ueq(C) The hydroxyl H atom was located in a difference Fourier map, and refined with Uiso(H) = 1.2 Ueq(O) and distance restraint O—H = 0.82 Å.