Diethyl­ammonium hydrogen oxalate

The structure of the title compound, C₄H₁₂N⁺·C₂HO₄⁻, consists of discrete oxalate monoanions and diethyl­ammonium cations. The N atom lies on a crystallographic twofold rotation axis and the oxalate ion is centrosymmetric. The oxalate monoanions are present as hydrogen-bonded linear chains. Conformationally extended diethyl­ammonium cations link the linear chains through three–centre N–H...O hydrogen bonds.

Key indicators

• Single-crystal X-ray study
• T = 298 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.039
• wR factor = 0.116
• Data-to-parameter ratio = 15.6

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT242_ALERT_2_C Check Low       Ueq as Compared to Neighbors for         C5
PLAT242_ALERT_2_C Check Low       Ueq as Compared to Neighbors for         C4
PLAT369_ALERT_2_C Long   C(sp2)-C(sp2) Bond  C4     -   C4_a   ...       1.54 Ang.
PLAT751_ALERT_4_C Bond    Calc     1.23000, Rep   1.230(10) ......  Senseless su
              O1   -H1      1.555   1.555
PLAT752_ALERT_4_C Angle   Calc      115.00, Rep  114.90(10) ......  Senseless su
              C4   -O1   -H1      1.555   1.555   1.555
PLAT755_ALERT_4_C D-H     Calc     1.23000, Rep   1.230(10) ......  Senseless su
              O1   -H1      1.555   1.555
PLAT756_ALERT_4_C H...A   Calc     1.23000, Rep   1.230(10) ......  Senseless su
              H1   -O1      1.555   3.666

   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

   0 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
   0 ALERT type 3 Indicator that the structure quality may be low
   4 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

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Computing details

Data collection: CrysAlis CCD (Oxford Diffraction, 2002); cell refinement: CrysAlis RED (Oxford Diffraction, 2006); data reduction: CrysAlis RED; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL (Sheldrick, 1990); software used to prepare material for publication: SHELXL97.

Diethylammonium hydrogen oxalate

Crystal data

C4H12N^+·C2HO4^−	F(000) = 176
Mr = 163.17	Dx = 1.158 Mg m^−3
Monoclinic, P2/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yc	Cell parameters from 1850 reflections
a = 7.0527 (4) Å	θ = 2.9–29.3°
b = 5.5465 (2) Å	µ = 0.10 mm^−1
c = 14.0317 (6) Å	T = 298 K
β = 121.544 (4)°	Block, colourless
V = 467.78 (4) Å^3	0.39 × 0.37 × 0.36 mm
Z = 2

Data collection

Oxford Diffraction Xcalibur diffractometer	744 reflections with I > 2σ(I)
Radiation source: Enhance (Mo) X-ray Source	Rint = 0.014
Graphite monochromator	θmax = 25.5°, θmin = 3.3°
Detector resolution: 1024x1024 with blocks 2x2 pixels mm^-1	h = −8→8
ω scans	k = −6→4
2852 measured reflections	l = −16→16
872 independent 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)] = 0.039	Hydrogen site location: difference Fourier map
wR(F^2) = 0.117	H atoms treated by a mixture of independent and constrained refinement
S = 1.09	w = 1/[σ^2(Fo^2) + (0.0778P)^2 + 0.1154P] where P = (Fo^2 + 2Fc^2)/3
872 reflections	(Δ/σ)max < 0.001
56 parameters	Δρmax = 0.15 e Å^−3
0 restraints	Δρmin = −0.17 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
O1	0.50394 (19)	0.29848 (16)	0.46517 (8)	0.0576 (4)
H1	0.5000	0.5000	0.5000	0.106 (10)*
O2	0.5074 (3)	0.14363 (19)	0.61145 (10)	0.0736 (5)
N3	0.5000	0.2384 (3)	0.2500	0.0494 (5)
H3	0.496 (3)	0.143 (4)	0.3019 (15)	0.071 (6)*
C4	0.5041 (2)	0.1255 (2)	0.52430 (11)	0.0432 (4)
C5	0.7053 (3)	0.3860 (3)	0.30505 (13)	0.0618 (5)
H5A	0.7000	0.4970	0.3570	0.074*
H5B	0.7134	0.4802	0.2490	0.074*
C6	0.9072 (4)	0.2332 (7)	0.3662 (2)	0.1203 (11)
H6A	1.0371	0.3339	0.4008	0.180*
H6B	0.9142	0.1251	0.3147	0.180*
H6C	0.9008	0.1419	0.4226	0.180*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.1178 (10)	0.0259 (5)	0.0530 (7)	−0.0007 (5)	0.0613 (7)	0.0004 (4)
O2	0.1623 (13)	0.0342 (6)	0.0578 (7)	−0.0012 (6)	0.0809 (8)	−0.0029 (5)
N3	0.0814 (13)	0.0423 (9)	0.0365 (9)	0.000	0.0391 (9)	0.000
C4	0.0745 (10)	0.0283 (7)	0.0385 (7)	0.0001 (6)	0.0377 (7)	−0.0001 (5)
C5	0.0752 (11)	0.0700 (11)	0.0449 (8)	−0.0068 (8)	0.0346 (8)	−0.0003 (7)
C6	0.0873 (18)	0.163 (3)	0.1017 (19)	0.0272 (18)	0.0431 (15)	0.0295 (19)

Geometric parameters (Å, º)

O1—C4	1.268 (2)	C5—C6	1.484 (3)
O1—H1	1.23 (1)	C5—H5A	0.9700
O2—C4	1.215 (2)	C5—H5B	0.9700
N3—C5	1.481 (2)	C6—H6A	0.9600
N3—C5^i	1.481 (2)	C6—H6B	0.9600
N3—H3	0.91 (2)	C6—H6C	0.9600
C4—C4^ii	1.538 (2)
C4—O1—H1	114.9 (1)	N3—C5—H5B	109.3
C5—N3—C5^i	112.89 (19)	C6—C5—H5B	109.3
C5—N3—H3	109.5 (11)	H5A—C5—H5B	108.0
C5^i—N3—H3	108.0 (11)	C5—C6—H6A	109.5
O2—C4—O1	126.07 (11)	C5—C6—H6B	109.5
O2—C4—C4^ii	119.88 (14)	H6A—C6—H6B	109.5
O1—C4—C4^ii	114.05 (12)	C5—C6—H6C	109.5
N3—C5—C6	111.5 (2)	H6A—C6—H6C	109.5
N3—C5—H5A	109.3	H6B—C6—H6C	109.5
C6—C5—H5A	109.3
C5^i—N3—C5—C6	175.9 (2)	O2—C4—C4^ii—O2^ii	180.0
O1—C4—C4^ii—O1^ii	180.0

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

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1···O1^iii	1.23 (1)	1.23 (1)	2.452 (1)	180
N3—H3···O1	0.91 (2)	2.42 (2)	3.0231 (9)	123 (2)
N3—H3···O2^ii	0.91 (2)	2.01 (2)	2.894 (2)	163 (2)

Symmetry codes: (ii) −x+1, −y, −z+1; (iii) −x+1, −y+1, −z+1.