Pyridinium (2R,3R)-tartrate

In the title compound, C₅H₆N⁺·C₄H₅O₆⁻, the pyridine mol­ecule exists as a cation and the tartaric acid mol­ecule as a semi-tartrate anion. The semi-tartrate anions are linked by O—H...O hydrogen bonds to form hollow columns running parallel to the a axis. The pyridinium cations, trapped in the columns, are linked to the semi-tartrate anions via strong N—H...O hydrogen bonds.

Key indicators

• Single-crystal X-ray study
• T = 300 K
• Mean [sigma](C-C) = 0.006 Å
• R factor = 0.045
• wR factor = 0.142
• Data-to-parameter ratio = 7.2

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT042_ALERT_1_C Calc. and Rep. MoietyFormula Strings Differ ....          ?
PLAT089_ALERT_3_C Poor Data / Parameter Ratio (Zmax .LT. 18) .....       7.17
PLAT250_ALERT_2_C Large U3/U1 Ratio for Average U(i,j) Tensor ....       2.85
PLAT250_ALERT_2_C Large U3/U1 Ratio for Average U(i,j) Tensor ....       2.74
PLAT340_ALERT_3_C Low Bond Precision on C-C bonds (x 1000) Ang ...          6

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           25.00
           From the CIF: _reflns_number_total               1068
           Count of symmetry unique reflns         1071
           Completeness (_total/calc)             99.72%
           TEST3: Check Friedels for noncentro structure
           Estimate of Friedel pairs measured         0
           Fraction of Friedel pairs measured     0.000
           Are heavy atom types Z>Si present         no

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

   1 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
   2 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: CAD-4 EXPRESS (Enraf–Nonius, 1994); cell refinement: CAD-4 EXPRESS; data reduction: XCAD4 (Harms & Wocadlo, 1996); program(s) used to solve structure: SHELXS97 (Sheldrick, 1990); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: PLATON (Spek, 2003); software used to prepare material for publication: SHELXL97.

Pyridinium tartrate

Crystal data

C5H6N^+·C4H5O6^−	F(000) = 480
Mr = 229.19	Dx = 1.492 Mg m^−3 Dm = 1.50 Mg m^−3 Dm measured by flotation in a liquid mixture of xylene and bromoform
Orthorhombic, P212121	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2ab	Cell parameters from 25 reflections
a = 5.0390 (13) Å	θ = 10–20°
b = 13.220 (2) Å	µ = 0.13 mm^−1
c = 15.318 (2) Å	T = 300 K
V = 1020.5 (3) Å^3	Prism, colourless
Z = 4	0.25 × 0.20 × 0.12 mm

Data collection

Nonius MACH3 four-circle diffractometer	852 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.033
Graphite monochromator	θmax = 25.0°, θmin = 2.0°
ω/2θ scans	h = 0→5
Absorption correction: ψ scan (North et al., 1968)	k = 0→15
Tmin = 0.97, Tmax = 0.99	l = −1→18
1149 measured reflections	2 standard reflections every 60 min
1068 independent reflections	intensity decay: none

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)] = 0.045	H-atom parameters constrained
wR(F^2) = 0.142	w = 1/[σ^2(Fo^2) + (0.1053P)^2 + 0.1376P] where P = (Fo^2 + 2Fc^2)/3
S = 1.07	(Δ/σ)max < 0.001
1068 reflections	Δρmax = 0.23 e Å^−3
149 parameters	Δρmin = −0.27 e Å^−3
0 restraints	Extinction correction: SHELXL97 (Sheldrick, 1997), Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.105 (15)

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
O1	0.3443 (7)	0.97041 (19)	0.31840 (14)	0.0441 (8)
H1	0.2941	0.9630	0.2679	0.066*
O2	0.0468 (7)	0.8499 (2)	0.34603 (18)	0.0531 (8)
O3	0.2348 (6)	0.81821 (17)	0.50660 (16)	0.0460 (8)
H3	0.0924	0.8029	0.4843	0.069*
O4	0.0663 (6)	1.0354 (2)	0.49590 (16)	0.0404 (7)
H4	−0.0265	1.0101	0.5341	0.061*
O5	0.6665 (7)	0.9719 (3)	0.60706 (19)	0.0603 (9)
O6	0.2619 (7)	1.0023 (2)	0.65705 (14)	0.0486 (8)
C1	0.2315 (8)	0.9027 (2)	0.3680 (2)	0.0342 (9)
C2	0.3544 (8)	0.8955 (2)	0.45771 (19)	0.0328 (9)
H2	0.5436	0.8801	0.4513	0.039*
C3	0.3257 (8)	0.9985 (2)	0.5032 (2)	0.0319 (8)
H3A	0.4421	1.0461	0.4725	0.038*
C4	0.4271 (8)	0.9903 (3)	0.5975 (2)	0.0338 (9)
C9	0.2095 (10)	0.6396 (3)	0.1866 (3)	0.0530 (12)
H9	0.0744	0.5927	0.1778	0.064*
N1	0.3365 (8)	0.6418 (2)	0.2624 (2)	0.0487 (10)
H1A	0.2902	0.6005	0.3030	0.058*
C5	0.5352 (10)	0.7067 (3)	0.2769 (2)	0.0468 (11)
H5	0.6245	0.7060	0.3300	0.056*
C6	0.6058 (10)	0.7733 (3)	0.2141 (3)	0.0497 (12)
H6	0.7417	0.8195	0.2241	0.060*
C7	0.4756 (10)	0.7723 (3)	0.1357 (3)	0.0532 (13)
H7	0.5233	0.8173	0.0918	0.064*
C8	0.2740 (11)	0.7043 (3)	0.1226 (3)	0.0565 (12)
H8	0.1830	0.7030	0.0698	0.068*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.078 (2)	0.0353 (13)	0.0188 (12)	−0.0077 (15)	−0.0029 (13)	0.0041 (9)
O2	0.080 (2)	0.0468 (15)	0.0328 (14)	−0.0176 (18)	−0.0082 (15)	0.0017 (12)
O3	0.082 (2)	0.0242 (12)	0.0315 (13)	−0.0080 (14)	−0.0073 (14)	0.0095 (10)
O4	0.0618 (16)	0.0344 (13)	0.0251 (12)	0.0107 (13)	−0.0017 (12)	0.0018 (10)
O5	0.0557 (19)	0.088 (2)	0.0369 (15)	−0.0011 (18)	−0.0102 (14)	0.0161 (15)
O6	0.0728 (18)	0.0562 (16)	0.0168 (12)	0.0012 (17)	0.0025 (13)	−0.0049 (12)
C1	0.063 (2)	0.0177 (14)	0.0221 (16)	0.0031 (19)	0.0035 (17)	−0.0031 (13)
C2	0.056 (2)	0.0201 (14)	0.0218 (16)	0.0054 (17)	0.0021 (17)	0.0016 (12)
C3	0.057 (2)	0.0199 (15)	0.0192 (15)	−0.0005 (17)	0.0000 (16)	0.0041 (13)
C4	0.059 (3)	0.0244 (16)	0.0182 (16)	−0.0062 (18)	−0.0038 (16)	0.0016 (12)
C9	0.066 (3)	0.037 (2)	0.056 (3)	−0.002 (2)	−0.004 (2)	−0.0145 (18)
N1	0.079 (2)	0.0275 (15)	0.0399 (18)	0.0062 (19)	0.0188 (18)	−0.0009 (13)
C5	0.076 (3)	0.0348 (19)	0.0296 (17)	0.016 (2)	−0.003 (2)	−0.0120 (17)
C6	0.067 (3)	0.0266 (17)	0.056 (3)	−0.001 (2)	−0.001 (2)	−0.0115 (17)
C7	0.094 (4)	0.0273 (18)	0.038 (2)	0.006 (2)	0.011 (2)	0.0050 (16)
C8	0.084 (3)	0.045 (2)	0.040 (2)	0.011 (3)	−0.015 (2)	−0.0093 (19)

Geometric parameters (Å, º)

O1—C1	1.305 (4)	C3—H3A	0.98
O1—H1	0.82	C9—N1	1.325 (6)
O2—C1	1.212 (5)	C9—C8	1.341 (7)
O3—C2	1.402 (4)	C9—H9	0.93
O3—H3	0.82	N1—C5	1.337 (6)
O4—C3	1.400 (5)	N1—H1A	0.86
O4—H4	0.82	C5—C6	1.352 (6)
O5—C4	1.239 (5)	C5—H5	0.93
O6—C4	1.245 (5)	C6—C7	1.368 (6)
C1—C2	1.510 (5)	C6—H6	0.93
C2—C3	1.536 (4)	C7—C8	1.371 (6)
C2—H2	0.98	C7—H7	0.93
C3—C4	1.537 (4)	C8—H8	0.93
C1—O1—H1	109.5	O6—C4—C3	117.2 (3)
C2—O3—H3	109.5	N1—C9—C8	120.6 (4)
C3—O4—H4	109.5	N1—C9—H9	119.7
O2—C1—O1	124.6 (3)	C8—C9—H9	119.7
O2—C1—C2	122.1 (3)	C9—N1—C5	121.4 (4)
O1—C1—C2	113.3 (3)	C9—N1—H1A	119.3
O3—C2—C1	110.9 (3)	C5—N1—H1A	119.3
O3—C2—C3	111.3 (3)	N1—C5—C6	119.8 (4)
C1—C2—C3	108.5 (2)	N1—C5—H5	120.1
O3—C2—H2	108.7	C6—C5—H5	120.1
C1—C2—H2	108.7	C5—C6—C7	119.4 (4)
C3—C2—H2	108.7	C5—C6—H6	120.3
O4—C3—C2	111.2 (3)	C7—C6—H6	120.3
O4—C3—C4	114.2 (3)	C6—C7—C8	119.4 (4)
C2—C3—C4	109.4 (3)	C6—C7—H7	120.3
O4—C3—H3A	107.2	C8—C7—H7	120.3
C2—C3—H3A	107.2	C9—C8—C7	119.4 (4)
C4—C3—H3A	107.2	C9—C8—H8	120.3
O5—C4—O6	126.1 (3)	C7—C8—H8	120.3
O5—C4—C3	116.6 (3)
O2—C1—C2—O3	3.0 (5)	C2—C3—C4—O5	64.6 (5)
O1—C1—C2—O3	−177.0 (3)	O4—C3—C4—O6	10.2 (4)
O2—C1—C2—C3	−119.5 (4)	C2—C3—C4—O6	−115.1 (4)
O1—C1—C2—C3	60.5 (4)	C8—C9—N1—C5	−1.3 (6)
O3—C2—C3—O4	−74.3 (3)	C9—N1—C5—C6	1.5 (6)
C1—C2—C3—O4	48.0 (4)	N1—C5—C6—C7	−1.1 (6)
O3—C2—C3—C4	52.8 (4)	C5—C6—C7—C8	0.6 (6)
C1—C2—C3—C4	175.0 (3)	N1—C9—C8—C7	0.8 (7)
O4—C3—C4—O5	−170.0 (3)	C6—C7—C8—C9	−0.4 (7)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1···O6^i	0.82	1.78	2.554 (3)	157
O3—H3···O3^ii	0.82	2.41	3.105 (3)	142
O4—H4···O5^iii	0.82	1.97	2.768 (4)	163
N1—H1A···O5^ii	0.86	1.79	2.644 (4)	172
C5—H5···O3^iv	0.93	2.58	3.481 (5)	162
C6—H6···O2^v	0.93	2.45	3.169 (5)	134
C7—H7···O4^i	0.93	2.48	3.331 (5)	152

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