2-Amino-5-methyl­pyridinium phosphate

The title compound, C₆H₉N₂⁺·H₂PO₄⁻, consists of 2-amino-5-methyl­pyridinium cations and H₂PO₄⁻ anions, which are held together by N—H...O hydrogen bonds.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.035
• wR factor = 0.093
• Data-to-parameter ratio = 13.1

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT066_ALERT_1_C Predicted and Reported Transmissions Identical .          ?
PLAT199_ALERT_1_C Check the Reported _cell_measurement_temperature        293 K
PLAT200_ALERT_1_C Check the Reported _diffrn_ambient_temperature .        293 K
PLAT242_ALERT_2_C Check Low       Ueq as Compared to Neighbors for          P
PLAT250_ALERT_2_C Large U3/U1 Ratio for Average U(i,j) Tensor ....       2.12
PLAT380_ALERT_4_C Check Incorrectly? Oriented X(sp2)-Methyl Moiety         C6
PLAT391_ALERT_3_C Deviating Methyl C6      H-C-H Bond Angle ......     101.00 Deg.

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   7 ALERT level C = Check and explain
   0 ALERT level G = General alerts; check

   3 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   2 ALERT type 2 Indicator that the structure model may be wrong or deficient
   1 ALERT type 3 Indicator that the structure quality may be low
   1 ALERT type 4 Improvement, methodology, query or suggestion

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Computing details

Data collection: PROCESS-AUTO (Rigaku, 2001); cell refinement: PROCESS-AUTO; data reduction: CrystalStructure (Rigaku, 2003); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: CrystalStructure; molecular graphics: SHELXTL (Siemens, 1998); software used to prepare material for publication: CrystalStructure.

2-Amino-5-methylpyridinium phosphate

Crystal data

C6H9N2^+·H2PO4^−	F(000) = 432.00
Mr = 206.14	Dx = 1.485 Mg m^−3
Monoclinic, P21/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 9071 reflections
a = 7.9850 (5) Å	θ = 2.7–27.5°
b = 10.9104 (6) Å	µ = 0.28 mm^−1
c = 11.1556 (7) Å	T = 293 K
β = 108.414 (2)°	Block, colorless
V = 922.11 (10) Å^3	0.45 × 0.45 × 0.31 mm
Z = 4

Data collection

Rigaku R-AXIS RAPID diffractometer	2111 independent reflections
Radiation source: fine-focus sealed tube	1664 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.027
Detector resolution: 10.00 pixels mm^-1	θmax = 27.5°, θmin = 2.7°
ω scans	h = −10→10
Absorption correction: multi-scan (ABSCOR; Higashi, 1995)	k = −12→14
Tmin = 0.880, Tmax = 0.916	l = −14→14
3577 measured reflections

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.035	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.093	All H-atom parameters refined
S = 0.97	w = 1/[σ^2(Fo^2) + (0.063P)^2] where P = (Fo^2 + 2Fc^2)/3
2115 reflections	(Δ/σ)max = 0.001
162 parameters	Δρmax = 0.23 e Å^−3
2 restraints	Δρmin = −0.36 e Å^−3

Special details

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 (Ų)

	x	y	z	Uiso*/Ueq
O4	0.20907 (16)	1.05590 (12)	0.58975 (13)	0.0522 (3)
O2	0.11125 (14)	0.85590 (10)	0.47512 (11)	0.0424 (3)
C6	0.0776 (3)	0.3191 (2)	0.3210 (2)	0.0549 (5)
C5	0.1403 (2)	0.53086 (15)	0.40857 (14)	0.0382 (4)
C4	0.1726 (2)	0.40947 (15)	0.42088 (15)	0.0396 (4)
P	0.25688 (5)	0.94985 (4)	0.51320 (3)	0.03094 (14)
N2	0.22879 (17)	0.61243 (13)	0.49967 (11)	0.0363 (3)
C3	0.3006 (3)	0.37036 (17)	0.53462 (18)	0.0510 (5)
N1	0.4398 (2)	0.66293 (16)	0.68740 (14)	0.0532 (4)
C2	0.3886 (3)	0.45191 (17)	0.62443 (17)	0.0512 (5)
C1	0.3555 (2)	0.57790 (15)	0.60630 (14)	0.0387 (4)
O1	0.43221 (14)	0.90043 (11)	0.59335 (11)	0.0415 (3)
O3	0.26796 (16)	1.00573 (13)	0.38754 (11)	0.0520 (4)
H6C	0.028 (3)	0.246 (2)	0.359 (2)	0.091 (8)*
H6B	−0.003 (4)	0.355 (3)	0.251 (3)	0.106 (9)*
H2N	0.186 (3)	0.693 (2)	0.4856 (17)	0.059 (6)*
H5	0.051 (2)	0.5727 (16)	0.3362 (16)	0.040 (5)*
H3	0.328 (2)	0.2816 (19)	0.5494 (17)	0.056 (5)*
H1A	0.517 (3)	0.640 (2)	0.757 (2)	0.065 (6)*
H2	0.480 (3)	0.429 (2)	0.699 (2)	0.076 (7)*
H2A	0.423 (3)	0.737 (2)	0.666 (2)	0.060 (6)*
H6A	0.146 (3)	0.282 (2)	0.288 (2)	0.090 (9)*
H3O	0.375 (2)	1.0403 (19)	0.400 (2)	0.075 (7)*
H4O	0.098 (2)	1.081 (2)	0.5555 (19)	0.065 (6)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O4	0.0360 (7)	0.0520 (8)	0.0615 (8)	−0.0007 (6)	0.0053 (6)	−0.0276 (6)
O2	0.0324 (6)	0.0302 (6)	0.0588 (7)	−0.0042 (4)	0.0063 (5)	−0.0040 (5)
C6	0.0650 (14)	0.0414 (12)	0.0495 (11)	−0.0044 (10)	0.0057 (10)	−0.0051 (9)
C5	0.0403 (9)	0.0354 (9)	0.0332 (7)	0.0004 (7)	0.0035 (6)	0.0033 (6)
C4	0.0424 (9)	0.0340 (9)	0.0381 (8)	−0.0009 (7)	0.0065 (7)	0.0024 (7)
P	0.0265 (2)	0.0297 (2)	0.0331 (2)	−0.00148 (14)	0.00438 (15)	−0.00021 (15)
N2	0.0411 (8)	0.0295 (8)	0.0338 (7)	0.0023 (5)	0.0053 (6)	0.0040 (5)
C3	0.0570 (11)	0.0320 (10)	0.0526 (10)	0.0037 (8)	0.0011 (9)	0.0103 (8)
N1	0.0686 (11)	0.0400 (10)	0.0355 (8)	−0.0097 (8)	−0.0058 (7)	0.0082 (7)
C2	0.0568 (12)	0.0391 (10)	0.0430 (9)	0.0019 (8)	−0.0050 (8)	0.0128 (8)
C1	0.0451 (9)	0.0353 (9)	0.0309 (7)	−0.0033 (7)	0.0052 (7)	0.0067 (6)
O1	0.0296 (6)	0.0420 (7)	0.0468 (6)	0.0006 (5)	0.0035 (5)	0.0131 (5)
O3	0.0323 (6)	0.0781 (10)	0.0392 (6)	−0.0035 (6)	0.0024 (5)	0.0166 (6)

Geometric parameters (Å, º)

P—O1	1.5031 (11)	C1—C2	1.402 (2)
P—O2	1.5071 (11)	C2—C3	1.358 (3)
P—O3	1.5566 (12)	C3—C4	1.420 (2)
P—O4	1.5555 (13)	C6—C4	1.502 (2)
O3—H3O	0.905 (16)	C4—C5	1.348 (2)
O4—H4O	0.889 (15)	C6—H6C	1.03 (3)
N1—C1	1.322 (2)	C6—H6B	0.93 (3)
N1—H1A	0.86 (2)	C6—H6A	0.85 (3)
N1—H2A	0.84 (2)	C5—H5	1.004 (16)
N2—C1	1.3492 (18)	C3—H3	0.99 (2)
N2—H2N	0.94 (2)	C2—H2	0.95 (2)
N2—C5	1.3677 (19)
P—O4—H4O	112.2 (13)	O4—P—O3	107.26 (8)
C4—C6—H6C	111.7 (12)	C1—N2—C5	122.75 (15)
C4—C6—H6B	114 (2)	C1—N2—H2N	122.8 (12)
H6C—C6—H6B	115 (2)	C5—N2—H2N	114.2 (12)
C4—C6—H6A	113.0 (16)	C2—C3—C4	121.39 (17)
H6C—C6—H6A	101 (2)	C2—C3—H3	118.7 (11)
H6B—C6—H6A	102 (3)	C4—C3—H3	119.9 (10)
C4—C5—N2	121.75 (15)	C1—N1—H1A	118.5 (15)
C4—C5—H5	126.4 (10)	C1—N1—H2A	118.6 (15)
N2—C5—H5	111.8 (10)	H1A—N1—H2A	123 (2)
C5—C4—C3	116.54 (15)	C3—C2—C1	120.38 (16)
C5—C4—C6	122.26 (16)	C3—C2—H2	123.3 (13)
C3—C4—C6	121.20 (17)	C1—C2—H2	116.2 (13)
O1—P—O2	114.48 (7)	N1—C1—N2	119.04 (16)
O1—P—O4	106.52 (7)	N1—C1—C2	123.86 (16)
O2—P—O4	111.06 (7)	N2—C1—C2	117.10 (15)
O1—P—O3	111.65 (7)	P—O3—H3O	110.2 (13)
O2—P—O3	105.72 (7)
N2—C5—C4—C3	1.4 (3)	C4—C3—C2—C1	−0.4 (3)
N2—C5—C4—C6	−179.39 (18)	C5—N2—C1—N1	177.30 (17)
C4—C5—N2—C1	1.1 (2)	C5—N2—C1—C2	−3.2 (2)
C5—C4—C3—C2	−1.7 (3)	C3—C2—C1—N1	−177.7 (2)
C6—C4—C3—C2	179.0 (2)	C3—C2—C1—N2	2.7 (3)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H2A···O1	0.84 (2)	1.97 (2)	2.789 (3)	164 (2)
N1—H1A···O2^i	0.86 (2)	2.31 (2)	3.073 (2)	148 (2)
N2—H2N···O2	0.94 (2)	1.87 (2)	2.802 (2)	174.2 (16)
O3—H3O···O1^ii	0.90 (2)	1.65 (2)	2.550 (3)	174 (2)
O4—H4O···O2^iii	0.89 (2)	1.74 (2)	2.612 (3)	166 (2)
C5—H5···O1^iv	1.003 (17)	2.589 (17)	3.464 (3)	145.8 (13)

Symmetry codes: (i) x+1/2, −y+3/2, z+1/2; (ii) −x+1, −y+2, −z+1; (iii) −x, −y+2, −z+1; (iv) x−1/2, −y+3/2, z−1/2.