3,6-Dioxaoctane-1,8-diammonium oxalate

The title compound, C₆H₁₈N₂O₂²⁺·C₂O₄²⁻, crystallizes with one half-cation and one half-anion in the asymmetric unit. It contains cyclic N—H...O hydrogen-bonded rings involving 3,6-dioxaoctane-1,8-diammonium and oxalate ions, forming a three-dimensional network.

Key indicators

• Single-crystal X-ray study
• T = 100 K
• Mean [sigma](C-C) = 0.002 Å
• R factor = 0.031
• wR factor = 0.076
• Data-to-parameter ratio = 12.3

checkCIF/PLATON results

No syntax errors found



Alert level B
PLAT369_ALERT_2_B Long   C(sp2)-C(sp2) Bond  C4     -   C4_b   ...       1.57 Ang.

Alert level C
RINTA01_ALERT_3_C  The value of Rint is greater than 0.10
            Rint given   0.105
PLAT020_ALERT_3_C The value of Rint is greater than 0.10 .........       0.10

   0 ALERT level A = In general: serious problem
   1 ALERT level B = Potentially serious problem
   2 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
   1 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

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Computing details

Data collection: X-AREA (Stoe & Cie, 2002); cell refinement: X-AREA; data reduction: X-RED32 (Stoe & Cie, 2002); program(s) used to solve structure: SHELXS97 (Sheldrick, 1990); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999).

3,6-dioxaoctane-1,8-diammonium oxalate

Crystal data

C6H18N2O2^2+·C2O4^2^−	F(000) = 256
Mr = 238.24	Dx = 1.473 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 7458 reflections
a = 7.5119 (7) Å	θ = 3.2–28.0°
b = 7.7072 (5) Å	µ = 0.13 mm^−1
c = 10.879 (1) Å	T = 100 K
β = 121.494 (6)°	Rounded prism, colorless
V = 537.07 (9) Å^3	0.35 × 0.28 × 0.17 mm
Z = 2

Data collection

Stoe diffractometer	1058 independent reflections
Radiation source: fine-focus sealed tube	952 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.105
Detector resolution: 6.67 pixels mm^-1	θmax = 26.0°, θmin = 3.2°
ω scans	h = −9→9
Absorption correction: integration (X-RED32; Stoe & Cie, 2002)	k = −9→9
Tmin = 0.961, Tmax = 0.983	l = −13→13
7458 measured reflections

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)] = 0.031	H atoms treated by a mixture of independent and constrained refinement
wR(F^2) = 0.076	w = 1/[σ^2(Fo^2) + (0.0231P)^2 + 0.1294P] where P = (Fo^2 + 2Fc^2)/3
S = 1.08	(Δ/σ)max < 0.001
1058 reflections	Δρmax = 0.36 e Å^−3
86 parameters	Δρmin = −0.18 e Å^−3
0 restraints	Extinction correction: SHELXL97, Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.093 (6)

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
C1	0.35077 (18)	0.47011 (14)	0.80105 (12)	0.0168 (3)
H1A	0.3886	0.3798	0.8727	0.020*
H1B	0.4142	0.5777	0.8513	0.020*
C2	0.43370 (18)	0.42409 (14)	0.70573 (13)	0.0170 (3)
H2A	0.5839	0.4090	0.7632	0.020*
H2B	0.3715	0.3166	0.6549	0.020*
C3	0.38857 (18)	0.51386 (14)	0.48181 (13)	0.0174 (3)
H3A	0.3235	0.6039	0.4092	0.021*
H3B	0.3096	0.4077	0.4417	0.021*
C4	0.00519 (16)	0.39874 (12)	0.00841 (12)	0.0130 (3)
N1	0.12072 (15)	0.49010 (11)	0.71617 (11)	0.0139 (2)
O1	0.38168 (13)	0.56231 (10)	0.60558 (9)	0.0180 (2)
O2	−0.00901 (13)	0.34013 (9)	0.11050 (9)	0.0189 (2)
O3	0.02758 (13)	0.31305 (9)	−0.07946 (9)	0.0177 (2)
H11A	0.078 (2)	0.5143 (16)	0.7790 (17)	0.018 (3)*
H11B	0.082 (2)	0.5780 (19)	0.6525 (16)	0.017 (3)*
H11C	0.059 (2)	0.392 (2)	0.6655 (16)	0.022 (3)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
C1	0.0197 (6)	0.0158 (5)	0.0165 (6)	−0.0007 (4)	0.0105 (5)	0.0007 (4)
C2	0.0178 (6)	0.0160 (5)	0.0201 (6)	0.0013 (4)	0.0119 (5)	0.0023 (4)
C3	0.0183 (6)	0.0187 (5)	0.0191 (6)	0.0004 (4)	0.0125 (5)	0.0009 (4)
C4	0.0139 (5)	0.0107 (5)	0.0150 (5)	0.0002 (4)	0.0079 (5)	0.0001 (4)
N1	0.0194 (5)	0.0106 (4)	0.0165 (5)	−0.0004 (4)	0.0128 (5)	−0.0004 (4)
O1	0.0249 (5)	0.0149 (4)	0.0220 (5)	0.0020 (3)	0.0178 (4)	0.0021 (3)
O2	0.0322 (5)	0.0120 (4)	0.0212 (5)	0.0028 (3)	0.0199 (4)	0.0027 (3)
O3	0.0272 (5)	0.0120 (4)	0.0210 (5)	−0.0004 (3)	0.0176 (4)	−0.0020 (3)

Geometric parameters (Å, º)

C1—N1	1.4817 (15)	C3—H3A	0.9700
C1—C2	1.5047 (15)	C3—H3B	0.9700
C1—H1A	0.9700	C4—O3	1.2434 (13)
C1—H1B	0.9700	C4—O2	1.2541 (13)
C2—O1	1.4247 (13)	C4—C4^ii	1.5688 (19)
C2—H2A	0.9700	N1—H11A	0.913 (16)
C2—H2B	0.9700	N1—H11B	0.901 (15)
C3—O1	1.4241 (14)	N1—H11C	0.909 (16)
C3—C3^i	1.521 (2)
N1—C1—C2	111.28 (9)	C3^i—C3—H3A	109.3
N1—C1—H1A	109.4	O1—C3—H3B	109.3
C2—C1—H1A	109.4	C3^i—C3—H3B	109.3
N1—C1—H1B	109.4	H3A—C3—H3B	107.9
C2—C1—H1B	109.4	O3—C4—O2	126.71 (9)
H1A—C1—H1B	108.0	O3—C4—C4^ii	117.21 (11)
O1—C2—C1	107.69 (9)	O2—C4—C4^ii	116.08 (11)
O1—C2—H2A	110.2	C1—N1—H11A	107.8 (9)
C1—C2—H2A	110.2	C1—N1—H11B	111.3 (9)
O1—C2—H2B	110.2	H11A—N1—H11B	108.7 (12)
C1—C2—H2B	110.2	C1—N1—H11C	110.5 (9)
H2A—C2—H2B	108.5	H11A—N1—H11C	110.9 (12)
O1—C3—C3^i	111.69 (12)	H11B—N1—H11C	107.7 (13)
O1—C3—H3A	109.3	C3—O1—C2	113.34 (8)
N1—C1—C2—O1	61.08 (11)	C1—C2—O1—C3	−160.71 (9)
C3^i—C3—O1—C2	−71.17 (14)

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

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H11A···O2^iii	0.913 (16)	1.904 (15)	2.7614 (12)	155.6 (12)
N1—H11A···O3^iv	0.913 (16)	2.352 (14)	2.9866 (12)	126.5 (10)
N1—H11B···O3^v	0.901 (15)	1.976 (15)	2.8138 (12)	154.0 (12)
N1—H11C···O2^vi	0.909 (16)	1.869 (16)	2.7530 (12)	163.6 (14)

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