Buy article online - an online subscription or single-article purchase is required to access this article.
The title compound, C6H9N2+·C6H4NO2-, has been formed by oxidative degradation of neat bis(2-pyridylmethyl)amine. Hydrogen bonds link the ions into infinite chains along the a axis.
Supporting information
CCDC reference: 179288
Freshly distilled bis(2-pyridylmethyl)amine (Larsen et al., 1986) was
left in a closed flask for about three months, during which colourless needles
of (I) formed. The mother liquor was decanted off and the crystals were washed
with diethyl ether and air dried.
Data collection: CAD-4 EXPRESS (Enraf-Nonius, 1994); cell refinement: CAD-4 EXPRESS; data reduction: DREADD (Blessing, 1987); program(s) used to solve structure: SHELXS97 (Sheldrick, 1990); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEPII (Johnson, 1976); software used to prepare material for publication: SHELXL97.
(2-Pyridylmethyl)ammonium pyridine-2-carboxylate
top
Crystal data top
C6H9N2+·C6H4NO2− | F(000) = 488 |
Mr = 231.25 | Dx = 1.307 Mg m−3 |
Monoclinic, P21/c | Cu Kα radiation, λ = 1.54180 Å |
a = 6.4233 (9) Å | Cell parameters from 20 reflections |
b = 9.0728 (18) Å | θ = 39.3–43.8° |
c = 20.265 (3) Å | µ = 0.75 mm−1 |
β = 95.700 (11)° | T = 122 K |
V = 1175.1 (3) Å3 | Needle, colourless |
Z = 4 | 0.19 × 0.06 × 0.02 mm |
Data collection top
Enraf-Nonius CAD-4 diffractometer | Rint = 0.025 |
Radiation source: fine-focus sealed tube | θmax = 75.0°, θmin = 4.4° |
Graphite monochromator | h = −8→8 |
ω/2θ scans | k = 0→11 |
4776 measured reflections | l = 0→25 |
2412 independent reflections | 5 standard reflections every 167 min |
2140 reflections with I > 2σ(I) | intensity decay: 4.5% |
Refinement top
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)] = 0.033 | All H-atom parameters refined |
wR(F2) = 0.119 | w = 1/[σ2(Fo2) + (0.1P)2] where P = (Fo2 + 2Fc2)/3 |
S = 1.00 | (Δ/σ)max < 0.001 |
2412 reflections | Δρmax = 0.29 e Å−3 |
207 parameters | Δρmin = −0.18 e Å−3 |
0 restraints | Extinction correction: SHELXL97 (Sheldrick, 1997), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
Primary atom site location: structure-invariant direct methods | Extinction coefficient: 0.0120 (14) |
Crystal data top
C6H9N2+·C6H4NO2− | V = 1175.1 (3) Å3 |
Mr = 231.25 | Z = 4 |
Monoclinic, P21/c | Cu Kα radiation |
a = 6.4233 (9) Å | µ = 0.75 mm−1 |
b = 9.0728 (18) Å | T = 122 K |
c = 20.265 (3) Å | 0.19 × 0.06 × 0.02 mm |
β = 95.700 (11)° | |
Data collection top
Enraf-Nonius CAD-4 diffractometer | Rint = 0.025 |
4776 measured reflections | 5 standard reflections every 167 min |
2412 independent reflections | intensity decay: 4.5% |
2140 reflections with I > 2σ(I) | |
Refinement top
R[F2 > 2σ(F2)] = 0.033 | 0 restraints |
wR(F2) = 0.119 | All H-atom parameters refined |
S = 1.00 | Δρmax = 0.29 e Å−3 |
2412 reflections | Δρmin = −0.18 e Å−3 |
207 parameters | |
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 | x | y | z | Uiso*/Ueq | |
C1 | 0.18390 (16) | 0.33894 (11) | 0.38952 (5) | 0.0202 (2) | |
C2 | 0.02792 (15) | 0.28040 (11) | 0.33368 (5) | 0.0196 (2) | |
C3 | 0.09091 (19) | 0.18135 (12) | 0.28715 (6) | 0.0270 (3) | |
C4 | −0.30398 (18) | 0.29114 (14) | 0.28076 (5) | 0.0292 (3) | |
C5 | −0.25469 (19) | 0.19433 (14) | 0.23157 (6) | 0.0309 (3) | |
C6 | −0.0539 (2) | 0.13815 (13) | 0.23503 (6) | 0.0324 (3) | |
C7 | 0.75862 (17) | 0.24344 (12) | 0.50895 (6) | 0.0261 (3) | |
C8 | 0.58952 (17) | 0.20647 (11) | 0.55274 (5) | 0.0229 (3) | |
C9 | 0.5797 (2) | 0.06513 (13) | 0.57965 (6) | 0.0309 (3) | |
C10 | 0.4236 (2) | 0.03386 (13) | 0.61969 (6) | 0.0348 (3) | |
C11 | 0.2816 (2) | 0.14310 (15) | 0.63175 (6) | 0.0332 (3) | |
C12 | 0.30333 (18) | 0.28077 (13) | 0.60322 (6) | 0.0287 (3) | |
O1 | 0.11368 (12) | 0.42770 (9) | 0.42944 (4) | 0.0274 (2) | |
O2 | 0.36799 (12) | 0.29485 (9) | 0.39017 (4) | 0.0283 (2) | |
N1 | −0.16701 (14) | 0.33402 (11) | 0.33111 (4) | 0.0246 (2) | |
N2 | 0.45458 (14) | 0.31311 (10) | 0.56429 (4) | 0.0236 (2) | |
N3 | 0.71603 (14) | 0.38256 (10) | 0.47272 (4) | 0.0203 (2) | |
H3 | 0.239 (3) | 0.1468 (18) | 0.2917 (8) | 0.041 (4)* | |
H4 | −0.449 (3) | 0.3261 (19) | 0.2794 (8) | 0.046 (4)* | |
H5 | −0.360 (3) | 0.1641 (18) | 0.1959 (8) | 0.041 (4)* | |
H6 | −0.017 (2) | 0.0712 (19) | 0.2007 (8) | 0.045 (4)* | |
H1N3 | 0.725 (2) | 0.4624 (18) | 0.5029 (8) | 0.036 (4)* | |
H2N3 | 0.585 (3) | 0.3764 (17) | 0.4482 (8) | 0.037 (4)* | |
H3N3 | 0.821 (3) | 0.3990 (17) | 0.4453 (8) | 0.038 (4)* | |
H7A | 0.898 (3) | 0.2511 (19) | 0.5348 (8) | 0.038 (4)* | |
H7B | 0.770 (3) | 0.163 (2) | 0.4775 (9) | 0.045 (4)* | |
H9 | 0.679 (2) | −0.0096 (18) | 0.5697 (7) | 0.036 (4)* | |
H10 | 0.407 (2) | −0.0658 (18) | 0.6390 (8) | 0.046 (4)* | |
H11 | 0.173 (3) | 0.1250 (19) | 0.6597 (9) | 0.051 (5)* | |
H12 | 0.207 (2) | 0.3641 (16) | 0.6127 (7) | 0.028 (3)* | |
Atomic displacement parameters (Å2) top | U11 | U22 | U33 | U12 | U13 | U23 |
C1 | 0.0193 (5) | 0.0209 (5) | 0.0208 (5) | −0.0019 (4) | 0.0035 (4) | −0.0009 (4) |
C2 | 0.0202 (5) | 0.0203 (5) | 0.0188 (5) | −0.0030 (4) | 0.0037 (4) | 0.0010 (4) |
C3 | 0.0294 (6) | 0.0246 (5) | 0.0270 (6) | 0.0016 (4) | 0.0026 (4) | −0.0049 (4) |
C4 | 0.0216 (5) | 0.0421 (6) | 0.0233 (6) | −0.0034 (5) | 0.0001 (4) | 0.0005 (5) |
C5 | 0.0323 (6) | 0.0379 (6) | 0.0214 (5) | −0.0095 (5) | −0.0025 (4) | −0.0001 (4) |
C6 | 0.0424 (7) | 0.0287 (6) | 0.0258 (6) | −0.0036 (5) | 0.0025 (5) | −0.0085 (4) |
C7 | 0.0228 (5) | 0.0225 (5) | 0.0330 (6) | 0.0056 (4) | 0.0023 (4) | −0.0002 (4) |
C8 | 0.0244 (5) | 0.0219 (5) | 0.0214 (5) | −0.0001 (4) | −0.0032 (4) | −0.0013 (4) |
C9 | 0.0420 (7) | 0.0220 (5) | 0.0279 (5) | 0.0028 (5) | −0.0010 (5) | 0.0005 (4) |
C10 | 0.0512 (8) | 0.0245 (5) | 0.0280 (6) | −0.0076 (5) | −0.0002 (5) | 0.0052 (4) |
C11 | 0.0364 (7) | 0.0367 (6) | 0.0265 (6) | −0.0097 (5) | 0.0030 (5) | 0.0043 (5) |
C12 | 0.0259 (5) | 0.0326 (6) | 0.0280 (6) | −0.0002 (4) | 0.0038 (4) | 0.0046 (4) |
O1 | 0.0206 (4) | 0.0339 (4) | 0.0279 (4) | −0.0012 (3) | 0.0036 (3) | −0.0131 (3) |
O2 | 0.0199 (4) | 0.0341 (4) | 0.0307 (4) | 0.0027 (3) | 0.0008 (3) | −0.0085 (3) |
N1 | 0.0197 (4) | 0.0326 (5) | 0.0219 (5) | −0.0014 (3) | 0.0036 (3) | −0.0015 (4) |
N2 | 0.0229 (5) | 0.0237 (5) | 0.0240 (5) | 0.0006 (3) | 0.0012 (3) | 0.0024 (3) |
N3 | 0.0178 (4) | 0.0221 (4) | 0.0213 (4) | 0.0006 (3) | 0.0035 (3) | −0.0026 (3) |
Geometric parameters (Å, º) top
C1—O2 | 1.2472 (13) | C7—H7A | 0.995 (17) |
C1—O1 | 1.2564 (13) | C7—H7B | 0.976 (18) |
C1—C2 | 1.5299 (14) | C8—N2 | 1.3351 (14) |
C2—N1 | 1.3395 (14) | C8—C9 | 1.3974 (15) |
C2—C3 | 1.3914 (15) | C9—C10 | 1.3807 (18) |
C3—C6 | 1.3924 (16) | C9—H9 | 0.967 (16) |
C3—H3 | 0.995 (16) | C10—C11 | 1.3853 (19) |
C4—N1 | 1.3370 (14) | C10—H10 | 0.995 (17) |
C4—C5 | 1.3884 (17) | C11—C12 | 1.3894 (17) |
C4—H4 | 0.985 (17) | C11—H11 | 0.954 (19) |
C5—C6 | 1.3821 (18) | C12—N2 | 1.3435 (14) |
C5—H5 | 0.979 (17) | C12—H12 | 1.006 (15) |
C6—H6 | 0.970 (17) | N3—H1N3 | 0.946 (16) |
C7—N3 | 1.4724 (14) | N3—H2N3 | 0.933 (16) |
C7—C8 | 1.5071 (15) | N3—H3N3 | 0.927 (17) |
| | | |
O2—C1—O1 | 126.84 (10) | N2—C8—C9 | 122.80 (11) |
O2—C1—C2 | 116.55 (9) | N2—C8—C7 | 117.40 (9) |
O1—C1—C2 | 116.61 (9) | C9—C8—C7 | 119.80 (10) |
N1—C2—C3 | 122.81 (10) | C10—C9—C8 | 118.78 (11) |
N1—C2—C1 | 116.34 (9) | C10—C9—H9 | 120.8 (9) |
C3—C2—C1 | 120.80 (9) | C8—C9—H9 | 120.4 (9) |
C2—C3—C6 | 118.57 (11) | C9—C10—C11 | 119.09 (11) |
C2—C3—H3 | 118.7 (9) | C9—C10—H10 | 121.9 (10) |
C6—C3—H3 | 122.7 (9) | C11—C10—H10 | 118.9 (10) |
N1—C4—C5 | 123.50 (11) | C10—C11—C12 | 118.34 (11) |
N1—C4—H4 | 118.6 (10) | C10—C11—H11 | 120.9 (11) |
C5—C4—H4 | 117.8 (10) | C12—C11—H11 | 120.8 (11) |
C6—C5—C4 | 118.37 (10) | N2—C12—C11 | 123.32 (11) |
C6—C5—H5 | 120.6 (10) | N2—C12—H12 | 116.1 (8) |
C4—C5—H5 | 121.1 (10) | C11—C12—H12 | 120.5 (8) |
C5—C6—C3 | 118.98 (11) | C4—N1—C2 | 117.76 (9) |
C5—C6—H6 | 119.1 (10) | C8—N2—C12 | 117.68 (10) |
C3—C6—H6 | 121.9 (10) | C7—N3—H1N3 | 109.7 (9) |
N3—C7—C8 | 112.05 (9) | C7—N3—H2N3 | 109.1 (10) |
N3—C7—H7A | 108.4 (10) | H1N3—N3—H2N3 | 112.7 (13) |
C8—C7—H7A | 111.7 (9) | C7—N3—H3N3 | 109.1 (10) |
N3—C7—H7B | 109.6 (10) | H1N3—N3—H3N3 | 105.1 (13) |
C8—C7—H7B | 109.0 (10) | H2N3—N3—H3N3 | 111.1 (13) |
H7A—C7—H7B | 105.8 (14) | | |
Hydrogen-bond geometry (Å, º) top
D—H···A | D—H | H···A | D···A | D—H···A |
N3—H1N3···O1i | 0.946 (16) | 1.913 (16) | 2.7672 (13) | 149.0 (13) |
N3—H2N3···O2 | 0.933 (16) | 1.885 (17) | 2.7722 (13) | 157.9 (14) |
N3—H3N3···N1ii | 0.927 (17) | 2.396 (16) | 3.0694 (13) | 129.4 (13) |
N3—H3N3···O1ii | 0.927 (17) | 1.956 (17) | 2.8117 (12) | 152.5 (14) |
Symmetry codes: (i) −x+1, −y+1, −z+1; (ii) x+1, y, z. |
Experimental details
Crystal data |
Chemical formula | C6H9N2+·C6H4NO2− |
Mr | 231.25 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 122 |
a, b, c (Å) | 6.4233 (9), 9.0728 (18), 20.265 (3) |
β (°) | 95.700 (11) |
V (Å3) | 1175.1 (3) |
Z | 4 |
Radiation type | Cu Kα |
µ (mm−1) | 0.75 |
Crystal size (mm) | 0.19 × 0.06 × 0.02 |
|
Data collection |
Diffractometer | Enraf-Nonius CAD-4 diffractometer |
Absorption correction | – |
No. of measured, independent and observed [I > 2σ(I)] reflections | 4776, 2412, 2140 |
Rint | 0.025 |
(sin θ/λ)max (Å−1) | 0.626 |
|
Refinement |
R[F2 > 2σ(F2)], wR(F2), S | 0.033, 0.119, 1.00 |
No. of reflections | 2412 |
No. of parameters | 207 |
H-atom treatment | All H-atom parameters refined |
Δρmax, Δρmin (e Å−3) | 0.29, −0.18 |
Hydrogen-bond geometry (Å, º) top
D—H···A | D—H | H···A | D···A | D—H···A |
N3—H1N3···O1i | 0.946 (16) | 1.913 (16) | 2.7672 (13) | 149.0 (13) |
N3—H2N3···O2 | 0.933 (16) | 1.885 (17) | 2.7722 (13) | 157.9 (14) |
N3—H3N3···N1ii | 0.927 (17) | 2.396 (16) | 3.0694 (13) | 129.4 (13) |
N3—H3N3···O1ii | 0.927 (17) | 1.956 (17) | 2.8117 (12) | 152.5 (14) |
Symmetry codes: (i) −x+1, −y+1, −z+1; (ii) x+1, y, z. |
Subscribe to Acta Crystallographica Section C: Structural Chemistry
The full text of this article is available to subscribers to the journal.
If you have already registered and are using a computer listed in your registration details, please email
support@iucr.org for assistance.
The amine bis(2-pyridylmethyl)amine is a versatile synthetic intermediate widely used in the preparation of polypyridyl ligands. The amine is usually distilled prior to use, and during the course of our studies in this field (Døssing et al., 1996, 1997), it has puzzled us that colourless needles begin to form after a couple of months' storage of the distilled amine. In order to characterize the decomposition product, a single-crystal was subjected to structure determination, which showed that the title salt, (I), consisting of a (2-pyridylmethyl)ammonium cation and a pyridine-2-carboxylate anion, had formed. A possible mechanism for the formation of (I) is shown below. \sch
In support of this mechanism, close scrutiny of a 1H NMR spectrum of a concentrated solution of aged bis(2-pyridylmethyl)amine in CD3CN indeed revealed the presence of low intensity peaks that could originate from pyridine-2-carboxaldehyde (7.61, 7.91, 8.77 and 10.00 p.p.m. in CD3CN). It is important to emphasize that these peaks are absent in a spectrum of freshly distilled bis(2-pyridylmethyl)amine. The presence of traces of impurities might catalyse the oxidative degradation. A similar (FeIII-promoted) oxidative degradation of a polypyridyl compound has been reported by Renz et al. (1999).
The Cambridge Structural Database (Allen et al., 1993) contains numerous structural reports of the pyridine-2-carboxylate anion, whereas the structure of the (2-pyridylmethyl)ammonium cation has no precedent. The bond lengths and angles in the cation and anion are normal. The pyridyl rings of the two ions are almost orthogonal [87.4 (5)°].
The structure of (I) shows four hydrogen bonds (Table 1) linking the ions into infinite chains along the a axis. The anion carboxylic O atoms and the pyridyl N atom act as hydrogen-bond acceptors, with the donor being the aliphatic N atom in the cation.