In the title compound, [C
5H
6N
3]Br·H
2O, the 2,6-diaminopyridine is protonated on the ring N atom. The cation is planar. The moieties are held together by extensive hydrogen bonding and by π–π interactions. The bromide ion is hydrogen bonded, as acceptor, to two H
2O molecules, with an average Br
H—O(H
2O) distance of 3.322 (11) Å, to the ring N atom Br
N—H(NH) 3.353 (3) Å, and to four amino N atoms, with an average Br
H—N(NH
2) 3.63 (14) Å. The water molecule bonds, as acceptor, to the pyridine N atom O
H—N(NH
2) 2.583 (5) Å. The closest π–π interaction is between pyridine ring planes, with an interplanar spacing 3.358 Å apart.
Supporting information
CCDC reference: 225701
Key indicators
- Single-crystal X-ray study
- T = 295 K
- Mean (C-C) = 0.006 Å
- R factor = 0.038
- wR factor = 0.100
- Data-to-parameter ratio = 14.3
checkCIF/PLATON results
No syntax errors found
Alert level A
PLAT027_ALERT_3_A _diffrn_reflns_theta_full too Low .............. 24.97 Deg.
Alert level B
PLAT415_ALERT_2_B Short Inter D-H..H-X H2A .. H5A = 1.98 Ang.
Alert level C
PLAT029_ALERT_3_C _diffrn_measured_fraction_theta_full Low ....... 0.99
PLAT042_ALERT_1_C Calc. and Rep. MoietyFormula Strings Differ .... ?
PLAT230_ALERT_2_C Hirshfeld Test Diff for N2 - C2 = 5.41 su
PLAT420_ALERT_2_C D-H Without Acceptor N2 - H2A ... ?
PLAT731_ALERT_1_C Bond Calc 0.88(4), Rep 0.882(19) ...... 2.11 su-Rat
O -H1 1.555 1.555
PLAT731_ALERT_1_C Bond Calc 0.88(5), Rep 0.881(19) ...... 2.63 su-Rat
O -H2 1.555 1.555
PLAT735_ALERT_1_C D-H Calc 0.88(4), Rep 0.882(19) ...... 2.11 su-Rat
O -H1 1.555 1.555
PLAT735_ALERT_1_C D-H Calc 0.88(5), Rep 0.881(19) ...... 2.63 su-Rat
O -H2 1.555 1.555
1 ALERT level A = In general: serious problem
1 ALERT level B = Potentially serious problem
8 ALERT level C = Check and explain
0 ALERT level G = General alerts; check
5 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
3 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
0 ALERT type 4 Improvement, methodology, query or suggestion
Data collection: XSCANS (Bruker, 1996b); cell refinement: XSCANS; data reduction: XSCANS; program(s) used to solve structure: XS in SHELXTL (Bruker, 1996); program(s) used to refine structure: XL in SHELXTL; molecular graphics: XP in SHELXTL; software used to prepare material for publication: XCIF in SHELXTL.
'2,6-Diaminopyridinium Bromide Hydrate'
top
Crystal data top
C5H8N3+·Br−·H2O | Z = 2 |
Mr = 208.07 | F(000) = 208 |
Triclinic, P1 | Dx = 1.722 Mg m−3 |
Hall symbol: -P 1 | Mo Kα radiation, λ = 0.71073 Å |
a = 7.1225 (12) Å | Cell parameters from 28 reflections |
b = 7.2333 (8) Å | θ = 5.9–18.1° |
c = 8.7082 (13) Å | µ = 5.06 mm−1 |
α = 91.557 (11)° | T = 295 K |
β = 102.518 (17)° | Parallelpiped, pink |
γ = 112.627 (11)° | 0.40 × 0.35 × 0.28 mm |
V = 401.21 (10) Å3 | |
Data collection top
Siemens P21 upgraded to P4 diffractometer | 1292 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.031 |
Graphite monochromator | θmax = 25.0°, θmin = 2.4° |
ω scans | h = −8→1 |
Absorption correction: psi-scan (XPREP in SHELXTL; Bruker, 1996) | k = −8→8 |
Tmin = 0.146, Tmax = 0.242 | l = −10→10 |
1781 measured reflections | 3 standard reflections every 97 reflections |
1412 independent reflections | intensity decay: <0.01% |
Refinement top
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)] = 0.038 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.100 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.09 | w = 1/[σ2(Fo2) + (0.0593P)2 + 0.2936P] where P = (Fo2 + 2Fc2)/3 |
1412 reflections | (Δ/σ)max < 0.001 |
99 parameters | Δρmax = 0.44 e Å−3 |
3 restraints | Δρmin = −0.63 e Å−3 |
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 | |
C5 | 0.6409 (6) | 0.7561 (6) | −0.0186 (5) | 0.0486 (9) | |
H5A | 0.7567 | 0.7581 | −0.0526 | 0.058* | |
Br | 0.88031 (6) | 0.66391 (6) | 0.63033 (4) | 0.0519 (2) | |
N2 | 0.1227 (4) | 0.7448 (5) | 0.1128 (4) | 0.0430 (7) | |
H2A | 0.0117 | 0.7102 | 0.0366 | 0.052* | |
H2B | 0.1184 | 0.7742 | 0.2079 | 0.052* | |
N1 | 0.2839 (5) | 0.7032 (5) | −0.0697 (4) | 0.0431 (7) | |
H1A | 0.1642 | 0.6709 | −0.1358 | 0.052* | |
C2 | 0.2996 (6) | 0.7528 (6) | 0.0837 (5) | 0.0455 (9) | |
N6 | 0.4118 (6) | 0.6507 (6) | −0.2809 (4) | 0.0597 (9) | |
H6A | 0.2892 | 0.6204 | −0.3423 | 0.072* | |
H6B | 0.5123 | 0.6484 | −0.3196 | 0.072* | |
C3 | 0.4874 (6) | 0.8053 (6) | 0.1924 (5) | 0.0501 (9) | |
H3A | 0.5009 | 0.8389 | 0.2993 | 0.060* | |
C6 | 0.4459 (6) | 0.7013 (6) | −0.1262 (5) | 0.0443 (8) | |
C4 | 0.6576 (6) | 0.8066 (6) | 0.1377 (5) | 0.0531 (10) | |
H4A | 0.7868 | 0.8430 | 0.2097 | 0.064* | |
O | 0.1830 (6) | 0.9045 (6) | 0.3976 (4) | 0.0673 (8) | |
H1 | 0.177 (8) | 1.024 (4) | 0.404 (6) | 0.075 (17)* | |
H2 | 0.130 (9) | 0.834 (7) | 0.470 (6) | 0.088 (19)* | |
Atomic displacement parameters (Å2) top | U11 | U22 | U33 | U12 | U13 | U23 |
C5 | 0.039 (2) | 0.049 (2) | 0.061 (3) | 0.0188 (17) | 0.0152 (17) | 0.0046 (18) |
Br | 0.0481 (3) | 0.0676 (3) | 0.0451 (3) | 0.0279 (2) | 0.01310 (18) | 0.00455 (18) |
N2 | 0.0290 (15) | 0.0647 (19) | 0.0409 (17) | 0.0226 (14) | 0.0123 (12) | 0.0068 (14) |
N1 | 0.0327 (15) | 0.0492 (17) | 0.0483 (18) | 0.0184 (13) | 0.0080 (13) | 0.0059 (14) |
C2 | 0.043 (2) | 0.0476 (19) | 0.051 (2) | 0.0209 (17) | 0.0173 (17) | 0.0097 (17) |
N6 | 0.055 (2) | 0.084 (3) | 0.047 (2) | 0.036 (2) | 0.0118 (16) | 0.0010 (18) |
C3 | 0.048 (2) | 0.058 (2) | 0.045 (2) | 0.0234 (19) | 0.0086 (17) | 0.0026 (17) |
C6 | 0.044 (2) | 0.0431 (18) | 0.051 (2) | 0.0212 (16) | 0.0156 (17) | 0.0088 (16) |
C4 | 0.039 (2) | 0.056 (2) | 0.059 (3) | 0.0187 (18) | 0.0032 (18) | 0.0000 (19) |
O | 0.078 (2) | 0.077 (2) | 0.064 (2) | 0.0399 (19) | 0.0344 (17) | 0.0142 (17) |
Geometric parameters (Å, º) top
C5—C4 | 1.367 (6) | C2—C3 | 1.368 (6) |
C5—C6 | 1.399 (6) | N6—C6 | 1.331 (5) |
C5—H5A | 0.9300 | N6—H6A | 0.8600 |
N2—C2 | 1.319 (5) | N6—H6B | 0.8600 |
N2—H2A | 0.8600 | C3—C4 | 1.392 (6) |
N2—H2B | 0.8600 | C3—H3A | 0.9300 |
N1—C2 | 1.343 (5) | C4—H4A | 0.9300 |
N1—C6 | 1.353 (5) | O—H1 | 0.882 (19) |
N1—H1A | 0.8600 | O—H2 | 0.881 (19) |
| | | |
C4—C5—C6 | 118.6 (4) | C6—N6—H6B | 120.0 |
C4—C5—H5A | 120.7 | H6A—N6—H6B | 120.0 |
C6—C5—H5A | 120.7 | C2—C3—C4 | 117.7 (4) |
C2—N2—H2A | 120.0 | C2—C3—H3A | 121.2 |
C2—N2—H2B | 120.0 | C4—C3—H3A | 121.2 |
H2A—N2—H2B | 120.0 | N6—C6—N1 | 118.3 (4) |
C2—N1—C6 | 123.7 (3) | N6—C6—C5 | 123.7 (4) |
C2—N1—H1A | 118.2 | N1—C6—C5 | 117.9 (4) |
C6—N1—H1A | 118.2 | C5—C4—C3 | 122.2 (4) |
N2—C2—N1 | 113.7 (3) | C5—C4—H4A | 118.9 |
N2—C2—C3 | 126.4 (4) | C3—C4—H4A | 118.9 |
N1—C2—C3 | 120.0 (4) | H1—O—H2 | 110 (3) |
C6—N6—H6A | 120.0 | | |
| | | |
C6—N1—C2—N2 | 180.0 (3) | C2—N1—C6—C5 | −0.7 (6) |
C6—N1—C2—C3 | 0.1 (6) | C4—C5—C6—N6 | 179.5 (4) |
N2—C2—C3—C4 | −179.3 (4) | C4—C5—C6—N1 | 0.7 (6) |
N1—C2—C3—C4 | 0.6 (6) | C6—C5—C4—C3 | −0.1 (6) |
C2—N1—C6—N6 | −179.6 (4) | C2—C3—C4—C5 | −0.6 (6) |
Hydrogen-bond geometry (Å, º) top
D—H···A | D—H | H···A | D···A | D—H···A |
N2—H2B···O | 0.86 | 1.76 | 2.583 (5) | 161 |
N1—H1A···Bri | 0.86 | 2.52 | 3.353 (3) | 162 |
N6—H6A···Brii | 0.86 | 2.91 | 3.464 (4) | 124 |
N6—H6A···Bri | 0.86 | 3.01 | 3.735 (4) | 144 |
N6—H6B···Briii | 0.86 | 2.71 | 3.553 (4) | 167 |
O—H1···Briv | 0.88 (2) | 2.46 (2) | 3.329 (4) | 169 (5) |
O—H2···Brv | 0.88 (2) | 2.47 (3) | 3.314 (4) | 161 (5) |
N2—H2B···Brvi | 0.86 | 3.51 | 3.752 (3) | 100 |
Symmetry codes: (i) x−1, y, z−1; (ii) −x+1, −y+1, −z; (iii) x, y, z−1; (iv) −x+1, −y+2, −z+1; (v) x−1, y, z; (vi) −x+1, −y+1, −z+1. |