




Supporting information
![]() | Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536810005180/lh2994sup1.cif |
![]() | Structure factor file (CIF format) https://doi.org/10.1107/S1600536810005180/lh2994Isup2.hkl |
CCDC reference: 770012
Key indicators
- Single-crystal X-ray study
- T = 296 K
- Mean
(C-C) = 0.002 Å
- R factor = 0.048
- wR factor = 0.138
- Data-to-parameter ratio = 16.7
checkCIF/PLATON results
No syntax errors found
Alert level C PLAT353_ALERT_3_C Long N-H Bond (0.87A) N1 - H1N1 ... 1.02 Ang. PLAT420_ALERT_2_C D-H Without Acceptor N3 - H2N3 ... ? PLAT911_ALERT_3_C Missing # FCF Refl Between THmin & STh/L= 0.600 2 PLAT153_ALERT_1_C The su's on the Cell Axes are Equal (x 100000) 20 Ang. PLAT912_ALERT_4_C Missing # of FCF Reflections Above STh/L= 0.600 41
Alert level G PLAT063_ALERT_4_G Crystal Size Likely too Large for Beam Size .... 0.72 mm PLAT720_ALERT_4_G Number of Unusual/Non-Standard Labels .......... 5
0 ALERT level A = In general: serious problem 0 ALERT level B = Potentially serious problem 5 ALERT level C = Check and explain 2 ALERT level G = General alerts; check 1 ALERT type 1 CIF construction/syntax error, inconsistent or missing data 1 ALERT type 2 Indicator that the structure model may be wrong or deficient 2 ALERT type 3 Indicator that the structure quality may be low 3 ALERT type 4 Improvement, methodology, query or suggestion 0 ALERT type 5 Informative message, check
A hot methanol solution (20 ml) of 2-amino-5-methylpyridine (54 mg, Aldrich) and 3-aminobenzoic acid (68 mg, Merck) were mixed and warmed over a heating magnetic stirrer for a few minutes. The resulting solution was allowed to cool slowly at room temperature and crystals of the title compound appeared after a few days.
The methyl H atoms were positioned geometrically and were refined using a riding model, with Uiso(H) = 1.5Ueq(C). A rotating group model was used for the methyl group. The remaining H atoms were located in a difference map and refined freely [N–H = 0.92 (2)–1.02 (2)Å, C–H = 0.96–1.00 (2)Å].
Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); 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) and PLATON (Spek, 2009).
C6H9N2+·C7H6NO2− | F(000) = 520 |
Mr = 245.28 | Dx = 1.341 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ybc | Cell parameters from 3778 reflections |
a = 10.0739 (2) Å | θ = 2.6–29.9° |
b = 10.9620 (2) Å | µ = 0.09 mm−1 |
c = 11.9641 (2) Å | T = 296 K |
β = 113.148 (1)° | Plate, brown |
V = 1214.83 (4) Å3 | 0.72 × 0.34 × 0.13 mm |
Z = 4 |
Bruker SMART APEXII CCD area-detector diffractometer | 3541 independent reflections |
Radiation source: fine-focus sealed tube | 2576 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.029 |
ϕ and ω scans | θmax = 30.1°, θmin = 2.2° |
Absorption correction: multi-scan (SADABS; Bruker, 2009) | h = −10→14 |
Tmin = 0.936, Tmax = 0.988 | k = −15→13 |
13305 measured reflections | l = −16→16 |
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)] = 0.048 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.138 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.07 | w = 1/[σ2(Fo2) + (0.0676P)2 + 0.1203P] where P = (Fo2 + 2Fc2)/3 |
3541 reflections | (Δ/σ)max = 0.001 |
212 parameters | Δρmax = 0.20 e Å−3 |
0 restraints | Δρmin = −0.26 e Å−3 |
C6H9N2+·C7H6NO2− | V = 1214.83 (4) Å3 |
Mr = 245.28 | Z = 4 |
Monoclinic, P21/c | Mo Kα radiation |
a = 10.0739 (2) Å | µ = 0.09 mm−1 |
b = 10.9620 (2) Å | T = 296 K |
c = 11.9641 (2) Å | 0.72 × 0.34 × 0.13 mm |
β = 113.148 (1)° |
Bruker SMART APEXII CCD area-detector diffractometer | 3541 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 2009) | 2576 reflections with I > 2σ(I) |
Tmin = 0.936, Tmax = 0.988 | Rint = 0.029 |
13305 measured reflections |
R[F2 > 2σ(F2)] = 0.048 | 0 restraints |
wR(F2) = 0.138 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.07 | Δρmax = 0.20 e Å−3 |
3541 reflections | Δρmin = −0.26 e Å−3 |
212 parameters |
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 esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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 > 2sigma(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. |
x | y | z | Uiso*/Ueq | ||
N1 | 0.03024 (11) | 0.31395 (9) | 0.56765 (8) | 0.0363 (2) | |
N2 | −0.07229 (13) | 0.27732 (11) | 0.70650 (10) | 0.0477 (3) | |
C1 | 0.12267 (13) | 0.37351 (11) | 0.52889 (10) | 0.0377 (3) | |
C2 | 0.01813 (13) | 0.34187 (11) | 0.67327 (10) | 0.0364 (3) | |
C3 | 0.10505 (14) | 0.43720 (12) | 0.74341 (10) | 0.0418 (3) | |
C4 | 0.19709 (14) | 0.49686 (12) | 0.70412 (11) | 0.0430 (3) | |
C5 | 0.20896 (13) | 0.46594 (11) | 0.59348 (10) | 0.0390 (3) | |
C6 | 0.31252 (16) | 0.53099 (14) | 0.55236 (13) | 0.0546 (4) | |
H6A | 0.2979 | 0.5045 | 0.4719 | 0.082* | |
H6B | 0.4097 | 0.5128 | 0.6069 | 0.082* | |
H6C | 0.2964 | 0.6173 | 0.5519 | 0.082* | |
O1 | 0.74312 (11) | 0.37847 (9) | 1.02381 (8) | 0.0506 (3) | |
O2 | 0.87300 (12) | 0.35863 (9) | 0.91200 (8) | 0.0552 (3) | |
N3 | 0.44474 (16) | 0.75758 (13) | 0.87306 (15) | 0.0620 (4) | |
C7 | 0.61001 (13) | 0.58920 (11) | 0.90248 (10) | 0.0380 (3) | |
C8 | 0.54279 (13) | 0.69494 (11) | 0.84017 (11) | 0.0396 (3) | |
C9 | 0.57809 (14) | 0.73551 (12) | 0.74452 (11) | 0.0415 (3) | |
C10 | 0.67681 (15) | 0.67294 (12) | 0.71301 (11) | 0.0424 (3) | |
C11 | 0.74400 (14) | 0.56839 (12) | 0.77538 (10) | 0.0392 (3) | |
C12 | 0.70967 (12) | 0.52632 (10) | 0.87065 (9) | 0.0343 (3) | |
C13 | 0.78005 (13) | 0.41271 (11) | 0.94066 (9) | 0.0371 (3) | |
H1 | 0.1227 (15) | 0.3450 (13) | 0.4509 (14) | 0.049 (4)* | |
H3 | 0.0993 (15) | 0.4581 (13) | 0.8200 (13) | 0.048 (4)* | |
H4 | 0.2602 (17) | 0.5628 (15) | 0.7561 (14) | 0.061 (4)* | |
H7 | 0.5865 (15) | 0.5593 (13) | 0.9703 (13) | 0.046 (4)* | |
H9 | 0.5270 (16) | 0.8131 (14) | 0.6969 (14) | 0.056 (4)* | |
H10 | 0.7025 (16) | 0.7023 (13) | 0.6453 (14) | 0.053 (4)* | |
H11 | 0.8116 (16) | 0.5214 (14) | 0.7520 (13) | 0.050 (4)* | |
H1N1 | −0.0365 (17) | 0.2494 (16) | 0.5130 (15) | 0.062 (5)* | |
H1N2 | −0.1357 (17) | 0.2226 (15) | 0.6504 (14) | 0.056 (4)* | |
H2N2 | −0.0953 (16) | 0.3031 (14) | 0.7699 (15) | 0.055 (4)* | |
H1N3 | 0.4107 (18) | 0.7223 (17) | 0.9247 (17) | 0.067 (5)* | |
H2N3 | 0.395 (2) | 0.8179 (18) | 0.8245 (18) | 0.077 (6)* |
U11 | U22 | U33 | U12 | U13 | U23 | |
N1 | 0.0421 (5) | 0.0357 (5) | 0.0327 (4) | −0.0030 (4) | 0.0163 (4) | −0.0047 (4) |
N2 | 0.0578 (7) | 0.0513 (7) | 0.0429 (5) | −0.0101 (6) | 0.0294 (5) | −0.0079 (5) |
C1 | 0.0405 (6) | 0.0398 (6) | 0.0341 (5) | −0.0004 (5) | 0.0162 (5) | −0.0022 (4) |
C2 | 0.0412 (6) | 0.0359 (6) | 0.0336 (5) | 0.0034 (5) | 0.0163 (4) | −0.0009 (4) |
C3 | 0.0457 (7) | 0.0433 (7) | 0.0359 (5) | 0.0016 (6) | 0.0156 (5) | −0.0092 (5) |
C4 | 0.0420 (7) | 0.0386 (6) | 0.0448 (6) | −0.0020 (5) | 0.0132 (5) | −0.0103 (5) |
C5 | 0.0372 (6) | 0.0371 (6) | 0.0421 (6) | 0.0004 (5) | 0.0148 (5) | −0.0003 (5) |
C6 | 0.0516 (8) | 0.0563 (9) | 0.0584 (8) | −0.0131 (7) | 0.0242 (6) | −0.0058 (6) |
O1 | 0.0655 (6) | 0.0505 (6) | 0.0456 (5) | 0.0114 (5) | 0.0323 (4) | 0.0126 (4) |
O2 | 0.0757 (7) | 0.0558 (6) | 0.0455 (5) | 0.0294 (5) | 0.0362 (5) | 0.0148 (4) |
N3 | 0.0660 (9) | 0.0531 (8) | 0.0837 (9) | 0.0201 (7) | 0.0475 (8) | 0.0152 (7) |
C7 | 0.0419 (6) | 0.0377 (6) | 0.0380 (5) | 0.0000 (5) | 0.0197 (5) | 0.0003 (5) |
C8 | 0.0363 (6) | 0.0370 (6) | 0.0461 (6) | −0.0003 (5) | 0.0169 (5) | −0.0025 (5) |
C9 | 0.0404 (7) | 0.0366 (6) | 0.0441 (6) | 0.0001 (5) | 0.0130 (5) | 0.0053 (5) |
C10 | 0.0463 (7) | 0.0442 (7) | 0.0387 (5) | −0.0021 (6) | 0.0187 (5) | 0.0062 (5) |
C11 | 0.0426 (7) | 0.0414 (7) | 0.0376 (5) | 0.0025 (5) | 0.0200 (5) | 0.0007 (5) |
C12 | 0.0378 (6) | 0.0339 (6) | 0.0308 (5) | −0.0006 (5) | 0.0130 (4) | −0.0014 (4) |
C13 | 0.0465 (7) | 0.0354 (6) | 0.0300 (5) | 0.0033 (5) | 0.0156 (4) | −0.0008 (4) |
N1—C2 | 1.3515 (14) | O1—C13 | 1.2490 (14) |
N1—C1 | 1.3593 (16) | O2—C13 | 1.2642 (15) |
N1—H1N1 | 1.018 (17) | N3—C8 | 1.3811 (18) |
N2—C2 | 1.3316 (16) | N3—H1N3 | 0.904 (19) |
N2—H1N2 | 0.938 (17) | N3—H2N3 | 0.89 (2) |
N2—H2N2 | 0.921 (17) | C7—C12 | 1.3888 (17) |
C1—C5 | 1.3607 (17) | C7—C8 | 1.4003 (17) |
C1—H1 | 0.984 (15) | C7—H7 | 0.986 (15) |
C2—C3 | 1.4090 (17) | C8—C9 | 1.3977 (18) |
C3—C4 | 1.3605 (19) | C9—C10 | 1.3771 (19) |
C3—H3 | 0.968 (14) | C9—H9 | 1.040 (16) |
C4—C5 | 1.4163 (17) | C10—C11 | 1.3897 (18) |
C4—H4 | 1.001 (16) | C10—H10 | 0.995 (15) |
C5—C6 | 1.4974 (19) | C11—C12 | 1.3933 (16) |
C6—H6A | 0.9600 | C11—H11 | 0.978 (15) |
C6—H6B | 0.9600 | C12—C13 | 1.5126 (16) |
C6—H6C | 0.9600 | ||
C2—N1—C1 | 122.40 (10) | H6B—C6—H6C | 109.5 |
C2—N1—H1N1 | 118.6 (9) | C8—N3—H1N3 | 119.2 (11) |
C1—N1—H1N1 | 118.9 (9) | C8—N3—H2N3 | 117.7 (13) |
C2—N2—H1N2 | 118.7 (10) | H1N3—N3—H2N3 | 119.6 (17) |
C2—N2—H2N2 | 120.4 (10) | C12—C7—C8 | 121.01 (11) |
H1N2—N2—H2N2 | 117.6 (13) | C12—C7—H7 | 119.6 (8) |
N1—C1—C5 | 122.30 (11) | C8—C7—H7 | 119.4 (8) |
N1—C1—H1 | 115.2 (8) | N3—C8—C9 | 121.04 (12) |
C5—C1—H1 | 122.5 (8) | N3—C8—C7 | 120.67 (12) |
N2—C2—N1 | 118.85 (11) | C9—C8—C7 | 118.28 (12) |
N2—C2—C3 | 123.65 (11) | C10—C9—C8 | 120.61 (11) |
N1—C2—C3 | 117.48 (11) | C10—C9—H9 | 120.8 (9) |
C4—C3—C2 | 119.94 (11) | C8—C9—H9 | 118.6 (9) |
C4—C3—H3 | 121.1 (8) | C9—C10—C11 | 121.03 (12) |
C2—C3—H3 | 119.0 (8) | C9—C10—H10 | 120.6 (9) |
C3—C4—C5 | 121.83 (11) | C11—C10—H10 | 118.4 (9) |
C3—C4—H4 | 119.0 (9) | C10—C11—C12 | 119.16 (12) |
C5—C4—H4 | 119.1 (9) | C10—C11—H11 | 121.8 (8) |
C1—C5—C4 | 116.05 (12) | C12—C11—H11 | 119.0 (8) |
C1—C5—C6 | 122.69 (11) | C7—C12—C11 | 119.91 (11) |
C4—C5—C6 | 121.25 (11) | C7—C12—C13 | 119.26 (10) |
C5—C6—H6A | 109.5 | C11—C12—C13 | 120.83 (11) |
C5—C6—H6B | 109.5 | O1—C13—O2 | 124.01 (11) |
H6A—C6—H6B | 109.5 | O1—C13—C12 | 117.84 (11) |
C5—C6—H6C | 109.5 | O2—C13—C12 | 118.15 (10) |
H6A—C6—H6C | 109.5 | ||
C2—N1—C1—C5 | −0.37 (18) | N3—C8—C9—C10 | 179.50 (12) |
C1—N1—C2—N2 | −178.35 (11) | C7—C8—C9—C10 | −0.18 (18) |
C1—N1—C2—C3 | 0.48 (17) | C8—C9—C10—C11 | −0.16 (19) |
N2—C2—C3—C4 | 178.51 (12) | C9—C10—C11—C12 | 0.43 (19) |
N1—C2—C3—C4 | −0.26 (18) | C8—C7—C12—C11 | 0.00 (18) |
C2—C3—C4—C5 | −0.1 (2) | C8—C7—C12—C13 | 179.81 (10) |
N1—C1—C5—C4 | 0.01 (18) | C10—C11—C12—C7 | −0.35 (18) |
N1—C1—C5—C6 | 179.17 (12) | C10—C11—C12—C13 | 179.84 (11) |
C3—C4—C5—C1 | 0.20 (19) | C7—C12—C13—O1 | 1.32 (17) |
C3—C4—C5—C6 | −178.97 (12) | C11—C12—C13—O1 | −178.87 (11) |
C12—C7—C8—N3 | −179.42 (12) | C7—C12—C13—O2 | −178.33 (10) |
C12—C7—C8—C9 | 0.26 (18) | C11—C12—C13—O2 | 1.48 (17) |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1N1···O2i | 1.017 (17) | 1.682 (17) | 2.6901 (14) | 170.6 (17) |
N2—H1N2···O1i | 0.939 (16) | 1.886 (16) | 2.8207 (15) | 173.3 (14) |
N2—H2N2···O2ii | 0.920 (17) | 1.947 (17) | 2.8650 (16) | 175.3 (16) |
N3—H1N3···O1iii | 0.903 (19) | 2.18 (2) | 3.027 (2) | 156.0 (17) |
Symmetry codes: (i) x−1, −y+1/2, z−1/2; (ii) x−1, y, z; (iii) −x+1, −y+1, −z+2. |
Experimental details
Crystal data | |
Chemical formula | C6H9N2+·C7H6NO2− |
Mr | 245.28 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 296 |
a, b, c (Å) | 10.0739 (2), 10.9620 (2), 11.9641 (2) |
β (°) | 113.148 (1) |
V (Å3) | 1214.83 (4) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.09 |
Crystal size (mm) | 0.72 × 0.34 × 0.13 |
Data collection | |
Diffractometer | Bruker SMART APEXII CCD area-detector diffractometer |
Absorption correction | Multi-scan (SADABS; Bruker, 2009) |
Tmin, Tmax | 0.936, 0.988 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 13305, 3541, 2576 |
Rint | 0.029 |
(sin θ/λ)max (Å−1) | 0.706 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.048, 0.138, 1.07 |
No. of reflections | 3541 |
No. of parameters | 212 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.20, −0.26 |
Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1N1···O2i | 1.017 (17) | 1.682 (17) | 2.6901 (14) | 170.6 (17) |
N2—H1N2···O1i | 0.939 (16) | 1.886 (16) | 2.8207 (15) | 173.3 (14) |
N2—H2N2···O2ii | 0.920 (17) | 1.947 (17) | 2.8650 (16) | 175.3 (16) |
N3—H1N3···O1iii | 0.903 (19) | 2.18 (2) | 3.027 (2) | 156.0 (17) |
Symmetry codes: (i) x−1, −y+1/2, z−1/2; (ii) x−1, y, z; (iii) −x+1, −y+1, −z+2. |
Pyridine and its derivatives play an important role in heterocyclic chemistry (Pozharski et al., 1997; Katritzky et al., 1996). Pyridine and its substituted derivatives are often involved in hydrogen-bond interactions (Jeffrey & Saenger, 1991; Jeffrey, 1997; Scheiner, 1997). The crystal structures of 2-amino-5-methylpyridine (Nahringbauer & Kvick, 1977), 2-amino-5-methylpyridinium phosphate (Feng et al., 2005), 2-amino-5-methylpyridinium 3-(4- hydroxy-3-methoxyphenyl)-2-propenoate monohydrate (Xuan et al., 2003) and 2-amino-5-methylpyridinium (2-amino-5-methylpyridine)trichlorozincate(II) (Jin et al., 2005) have been reported in the literature. In order to study some interesting hydrogen bonding interactions, the synthesis and structure of the title salt is presented here.
The asymmetric unit (Fig. 1) contains a 2-amino-5-methylpyridinium cation and a 3-aminobenzoate anion. The proton transfer from the carboxyl group to atom N1 of 2-amino-5-methylpyridine resulted in the widening of C2—N1—C1 angle of the pyridinium ring to 122.40 (10)°, compared to the corresponding angle of 117.4° (no standard uncertainty available) in neutral 2-amino-5-methylpyridine (Nahringbauer & Kvick, 1977). The 2-amino-5-methylpyridinium cation is essentially planar, with a maximum deviation of 0.002 (1)Å for atom N1. The bond lengths (Allen et al., 1987) and angles are within normal ranges.
In the crystal structure (Fig. 2), the protonated N1 atom and 2-amino group (N2) are hydrogen-bonded to the carboxylate oxygen atoms (O1 and O2) via a pair of N—H···O hydrogen bonds forming a ring motif R22(8) (Bernstein et al., 1995). The symmetry-related 3-aminobenzoate molecules are linked through N3—H1N3···O1(-x+1, -y+1, -z+2) hydrogen-bonding to form a R22(14) ring motif (Table 1). The cystal structure is further stabilized by π···π stacking interaction between the pyridine rings (C1–C5/N1) and benzene ring (C7–C12) with centroid- to-centroid distance of 3.7594 (8)Å [symmetry codes: 1-x, 1/2+y, 3/2-z and 1-x, -1/2+y, 3/2-z ].