4-Amino-(1-carboxy­meth­yl)pyridinium chloride

In the title structure, C₇H₉N₂O₂⁺·Cl⁻, the dihedral angle between the pyridinium ring and carboxy­methyl­ene group is 70.5 (1)°. The anions and cations are inter­connected by inter­molecular N—H...Cl and O—H...Cl hydrogen bonds, forming a three-dimensional network.

Key indicators

• Single-crystal X-ray study
• T = 115 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.043
• wR factor = 0.107
• Data-to-parameter ratio = 18.1

checkCIF/PLATON results

No syntax errors found



Alert level C
STRVA01_ALERT_4_C           Flack test results are ambiguous.
           From the CIF: _refine_ls_abs_structure_Flack    0.320
           From the CIF: _refine_ls_abs_structure_Flack_su    0.080
PLAT033_ALERT_2_C Flack Parameter Value Deviates from Zero .......       0.32

Alert level G
REFLT03_ALERT_4_G Please check that the estimate of the number of Friedel pairs is
            correct. If it is not, please give the correct count in the
            _publ_section_exptl_refinement section of the submitted CIF.
           From the CIF: _diffrn_reflns_theta_max           28.66
           From the CIF: _reflns_number_total               2149
           Count of symmetry unique reflns         1292
           Completeness (_total/calc)            166.33%
           TEST3: Check Friedels for noncentro structure
           Estimate of Friedel pairs measured       857
           Fraction of Friedel pairs measured     0.663
           Are heavy atom types Z>Si present        yes

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

   0 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
   0 ALERT type 3 Indicator that the structure quality may be low
   2 ALERT type 4 Improvement, methodology, query or suggestion

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Computing details

Data collection: COLLECT (Nonius, 2000); cell refinement: SCALEPACK (Otwinowski & Minor, 1997); data reduction: SCALEPACK and DENZO (Otwinowski & Minor, 1997); program(s) used to solve structure: SIR92 (Altomare et al., 1994); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEP-3 for Windows (Version 1.07; Farrugia, 1997) and PLATON (Spek, 2003); software used to prepare material for publication: SHELXL97.

4-Amino-(1-carboxymethyl)pyridinium chloride

Crystal data

C7H9N2O2^+·Cl^−	F(000) = 392
Mr = 188.61	Dx = 1.490 Mg m^−3
Orthorhombic, P212121	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2ab	Cell parameters from 1310 reflections
a = 4.4324 (5) Å	θ = 2.5–28.7°
b = 8.8524 (10) Å	µ = 0.41 mm^−1
c = 21.431 (3) Å	T = 115 K
V = 840.90 (18) Å^3	Needle fragment, colourless
Z = 4	0.25 × 0.12 × 0.10 mm

Data collection

Nonius KappaCCD (with an Cryosystems Oxford Cryostream cooler) diffractometer	2149 independent reflections
Radiation source: fine-focus sealed tube	1900 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.064
ω scans with κ offsets	θmax = 28.7°, θmin = 3.0°
Absorption correction: multi-scan (SCALEPACK; Otwinowski & Minor, 1997)	h = −5→5
Tmin = 0.904, Tmax = 0.960	k = −11→11
18548 measured reflections	l = −28→28

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F^2 > 2σ(F^2)] = 0.044	H atoms treated by a mixture of independent and constrained refinement
wR(F^2) = 0.107	w = 1/[σ^2(Fo^2) + (0.0668P)^2 + 0.092P] where P = (Fo^2 + 2Fc^2)/3
S = 1.11	(Δ/σ)max = 0.001
2149 reflections	Δρmax = 0.42 e Å^−3
119 parameters	Δρmin = −0.50 e Å^−3
0 restraints	Absolute structure: Flack (1983), 859 Friedel pairs
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: 0.32 (8)

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
Cl1	0.60083 (12)	0.32462 (6)	0.67439 (2)	0.02534 (15)
O1	0.8708 (4)	0.34638 (17)	0.54780 (7)	0.0238 (3)
H1O	0.788 (6)	0.350 (3)	0.5779 (14)	0.036*
O2	0.5250 (4)	0.52232 (18)	0.52235 (7)	0.0262 (4)
N1	0.7427 (4)	0.54567 (19)	0.40290 (8)	0.0192 (4)
N2	0.2727 (5)	0.8335 (2)	0.28746 (8)	0.0246 (4)
H1N	0.256 (6)	0.925 (3)	0.2961 (13)	0.030*
H2N	0.157 (5)	0.795 (3)	0.2557 (12)	0.030*
C1	0.5705 (5)	0.4895 (2)	0.35559 (9)	0.0199 (4)
H1	0.5585	0.3833	0.3497	0.024*
C2	0.4152 (5)	0.5831 (2)	0.31652 (9)	0.0204 (4)
H2	0.2984	0.5414	0.2836	0.024*
C3	0.4263 (5)	0.7413 (2)	0.32456 (9)	0.0197 (4)
C4	0.6114 (5)	0.7966 (2)	0.37398 (9)	0.0220 (4)
H4	0.6304	0.9023	0.3808	0.026*
C5	0.7604 (5)	0.6975 (2)	0.41131 (10)	0.0220 (4)
H5	0.8810	0.7356	0.4444	0.026*
C6	0.8933 (5)	0.4438 (2)	0.44637 (9)	0.0224 (4)
H6A	1.1059	0.4757	0.4516	0.027*
H6B	0.8927	0.3402	0.4290	0.027*
C7	0.7379 (5)	0.4432 (2)	0.50968 (10)	0.0196 (4)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Cl1	0.0353 (3)	0.0232 (2)	0.0176 (2)	−0.0036 (2)	0.0044 (2)	−0.00215 (19)
O1	0.0279 (8)	0.0290 (8)	0.0147 (6)	0.0042 (7)	0.0014 (6)	0.0028 (6)
O2	0.0315 (8)	0.0276 (8)	0.0193 (7)	0.0067 (6)	0.0038 (6)	0.0011 (6)
N1	0.0218 (9)	0.0225 (9)	0.0134 (8)	0.0013 (7)	0.0003 (7)	−0.0006 (6)
N2	0.0361 (10)	0.0209 (9)	0.0168 (8)	0.0035 (9)	−0.0022 (8)	−0.0008 (7)
C1	0.0240 (11)	0.0201 (9)	0.0156 (9)	−0.0012 (8)	0.0033 (8)	−0.0025 (7)
C2	0.0237 (10)	0.0229 (9)	0.0145 (9)	−0.0009 (8)	−0.0002 (9)	−0.0011 (7)
C3	0.0241 (10)	0.0229 (9)	0.0122 (8)	0.0001 (8)	0.0057 (10)	0.0002 (8)
C4	0.0275 (10)	0.0193 (9)	0.0192 (9)	−0.0035 (9)	0.0019 (9)	−0.0030 (7)
C5	0.0230 (10)	0.0255 (11)	0.0176 (9)	−0.0034 (9)	0.0005 (8)	−0.0034 (8)
C6	0.0246 (10)	0.0266 (10)	0.0158 (9)	0.0058 (10)	0.0014 (9)	0.0009 (7)
C7	0.0217 (10)	0.0188 (9)	0.0183 (10)	−0.0028 (9)	−0.0004 (8)	−0.0018 (7)

Geometric parameters (Å, º)

O1—C7	1.322 (3)	C1—H1	0.9500
O1—H1O	0.74 (3)	C2—C3	1.412 (3)
O2—C7	1.206 (3)	C2—H2	0.9500
N1—C5	1.358 (3)	C3—C4	1.427 (3)
N1—C1	1.363 (3)	C4—C5	1.359 (3)
N1—C6	1.458 (3)	C4—H4	0.9500
N2—C3	1.327 (3)	C5—H5	0.9500
N2—H1N	0.83 (3)	C6—C7	1.521 (3)
N2—H2N	0.92 (3)	C6—H6A	0.9900
C1—C2	1.365 (3)	C6—H6B	0.9900
C7—O1—H1O	107 (2)	C5—C4—C3	119.67 (18)
C5—N1—C1	119.49 (18)	C5—C4—H4	120.2
C5—N1—C6	120.04 (18)	C3—C4—H4	120.2
C1—N1—C6	120.38 (17)	N1—C5—C4	122.21 (19)
C3—N2—H1N	120.6 (19)	N1—C5—H5	118.9
C3—N2—H2N	119.9 (16)	C4—C5—H5	118.9
H1N—N2—H2N	119 (2)	N1—C6—C7	111.40 (18)
N1—C1—C2	121.14 (18)	N1—C6—H6A	109.3
N1—C1—H1	119.4	C7—C6—H6A	109.3
C2—C1—H1	119.4	N1—C6—H6B	109.3
C1—C2—C3	120.68 (19)	C7—C6—H6B	109.3
C1—C2—H2	119.7	H6A—C6—H6B	108.0
C3—C2—H2	119.7	O2—C7—O1	125.85 (19)
N2—C3—C2	121.3 (2)	O2—C7—C6	123.55 (19)
N2—C3—C4	121.93 (19)	O1—C7—C6	110.60 (17)
C2—C3—C4	116.80 (18)
C5—N1—C1—C2	−0.1 (3)	C1—N1—C5—C4	0.0 (3)
C6—N1—C1—C2	176.47 (19)	C6—N1—C5—C4	−176.54 (19)
N1—C1—C2—C3	−0.7 (3)	C3—C4—C5—N1	0.8 (3)
C1—C2—C3—N2	−179.00 (18)	C5—N1—C6—C7	70.3 (2)
C1—C2—C3—C4	1.4 (3)	C1—N1—C6—C7	−106.2 (2)
N2—C3—C4—C5	179.0 (2)	N1—C6—C7—O2	−2.8 (3)
C2—C3—C4—C5	−1.5 (3)	N1—C6—C7—O1	177.80 (17)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1O···Cl1	0.74 (3)	2.24 (3)	2.9712 (16)	169 (3)
N2—H1N···Cl1^i	0.83 (3)	2.41 (3)	3.226 (2)	168 (3)
N2—H2N···Cl1^ii	0.92 (3)	2.34 (3)	3.252 (2)	174 (2)

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