(E,E)-1,8-Dioxacyclo­tetra­deca-3,10-diene-2,9-dione

The title compound, C₁₂H₁₆O₄, has an unconventional weak hydrogen-bonding pattern. A network of weak inter­molecular hydrogen bonds between an alkane group and the carbonyl groups stabilizes the mol­ecular packing. The asymmetric unit contains one half-mol­ecule and the complete mol­ecule is generated by an inversion center.

Key indicators

• Single-crystal X-ray study
• T = 301 K
• Mean [sigma](C-C) = 0.002 Å
• R factor = 0.042
• wR factor = 0.123
• Data-to-parameter ratio = 17.6

checkCIF/PLATON results

No syntax errors found



Alert level C
ABSTM02_ALERT_3_C  The ratio of expected to reported Tmax/Tmin(RR') is < 0.90
            Tmin and Tmax reported:      0.754     0.984
            Tmin(prime) and Tmax expected:      0.952     0.984
            RR(prime) =      0.792
            Please check that your absorption correction is appropriate.
PLAT061_ALERT_3_C Tmax/Tmin Range Test RR' too Large .............       0.79
PLAT480_ALERT_4_C Long H...A H-Bond Reported H4A    ..  O1      ..       2.67 Ang.

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   3 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
   0 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: SMART (Bruker, 2003); cell refinement: SMART; data reduction: SAINT-Plus (Bruker, 2003); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL (Bruker, 2003); software used to prepare material for publication: SHELXTL.

(E,E)-1,8-Dioxacyclotetradeca-3,10-diene-2,9-dione

Crystal data

C12H16O4	Z = 1
Mr = 224.25	F(000) = 120
Triclinic, P1	Dx = 1.272 Mg m^−3
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 6.442 (3) Å	Cell parameters from 938 reflections
b = 6.665 (3) Å	θ = 28.3–0.9°
c = 7.757 (4) Å	µ = 0.10 mm^−1
α = 72.037 (7)°	T = 301 K
β = 77.661 (8)°	Column, colorless
γ = 68.409 (7)°	0.51 × 0.41 × 0.17 mm
V = 292.7 (2) Å^3

Data collection

Bruker SMART CCD area-detector diffractometer	1440 independent reflections
Radiation source: fine-focus sealed tube	1278 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.020
φ and ω scans	θmax = 28.3°, θmin = 2.8°
Absorption correction: multi-scan (SADABS; Sheldrick, 2002)	h = −8→8
Tmin = 0.754, Tmax = 0.984	k = −8→8
5226 measured reflections	l = −10→10

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)] = 0.042	H atoms treated by a mixture of independent and constrained refinement
wR(F^2) = 0.123	w = 1/[σ^2(Fo^2) + (0.0712P)^2 + 0.031P] where P = (Fo^2 + 2Fc^2)/3
S = 1.05	(Δ/σ)max < 0.001
1440 reflections	Δρmax = 0.20 e Å^−3
82 parameters	Δρmin = −0.16 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: 0.17 (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
O2	0.33098 (13)	0.81151 (13)	−0.11673 (10)	0.0483 (3)
C1	0.59655 (19)	0.72251 (16)	0.07816 (15)	0.0446 (3)
C2	0.55029 (19)	0.77086 (17)	−0.11113 (15)	0.0454 (3)
C3	0.7891 (2)	0.71892 (17)	0.11454 (15)	0.0465 (3)
O1	0.68569 (16)	0.7824 (2)	−0.24410 (12)	0.0713 (3)
C4	0.8471 (2)	0.69366 (19)	0.29840 (16)	0.0537 (3)
H4A	0.9627	0.5508	0.3339	0.064*
H4B	0.7154	0.6932	0.3866	0.064*
C5	0.2471 (2)	0.8963 (2)	−0.29373 (16)	0.0558 (3)
H5A	0.1837	0.7937	−0.3114	0.067*
H5B	0.3698	0.9086	−0.3893	0.067*
C6	0.9303 (2)	0.8781 (2)	0.30483 (17)	0.0551 (3)
H6A	0.9970	0.8329	0.4174	0.066*
H6B	1.0477	0.8923	0.2047	0.066*
H99A	0.473 (2)	0.712 (2)	0.167 (2)	0.058 (4)*
H99B	0.903 (2)	0.736 (2)	0.0155 (19)	0.056 (4)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O2	0.0550 (5)	0.0481 (4)	0.0446 (4)	−0.0188 (3)	−0.0124 (3)	−0.0087 (3)
C1	0.0498 (6)	0.0361 (5)	0.0437 (5)	−0.0097 (4)	−0.0075 (5)	−0.0080 (4)
C2	0.0514 (6)	0.0372 (5)	0.0472 (6)	−0.0100 (4)	−0.0076 (5)	−0.0142 (4)
C3	0.0499 (6)	0.0390 (5)	0.0454 (6)	−0.0070 (4)	−0.0080 (5)	−0.0108 (4)
O1	0.0604 (6)	0.1010 (8)	0.0499 (5)	−0.0190 (5)	−0.0001 (4)	−0.0284 (5)
C4	0.0597 (7)	0.0478 (6)	0.0483 (6)	−0.0105 (5)	−0.0186 (5)	−0.0051 (5)
C5	0.0686 (8)	0.0579 (7)	0.0480 (6)	−0.0211 (6)	−0.0186 (5)	−0.0142 (5)
C6	0.0546 (7)	0.0628 (7)	0.0495 (6)	−0.0173 (5)	−0.0195 (5)	−0.0094 (5)

Geometric parameters (Å, º)

O2—C2	1.3449 (15)	C4—C6	1.5281 (19)
O2—C5	1.4528 (14)	C4—H4A	0.9700
C1—C3	1.3201 (18)	C4—H4B	0.9700
C1—C2	1.4742 (16)	C5—C6^i	1.5069 (19)
C1—H99A	0.942 (15)	C5—H5A	0.9700
C2—O1	1.2027 (15)	C5—H5B	0.9700
C3—C4	1.4952 (16)	C6—H6A	0.9700
C3—H99B	0.953 (15)	C6—H6B	0.9700
C2—O2—C5	118.29 (9)	C6—C4—H4B	108.9
C3—C1—C2	121.28 (11)	H4A—C4—H4B	107.7
C3—C1—H99A	123.9 (9)	O2—C5—C6^i	109.82 (9)
C2—C1—H99A	114.5 (9)	O2—C5—H5A	109.7
O1—C2—O2	123.96 (11)	C6^i—C5—H5A	109.7
O1—C2—C1	125.48 (12)	O2—C5—H5B	109.7
O2—C2—C1	110.49 (10)	C6^i—C5—H5B	109.7
C1—C3—C4	126.20 (11)	H5A—C5—H5B	108.2
C1—C3—H99B	118.0 (8)	C5^i—C6—C4	115.19 (11)
C4—C3—H99B	115.8 (8)	C5^i—C6—H6A	108.5
C3—C4—C6	113.36 (10)	C4—C6—H6A	108.5
C3—C4—H4A	108.9	C5^i—C6—H6B	108.5
C6—C4—H4A	108.9	C4—C6—H6B	108.5
C3—C4—H4B	108.9	H6A—C6—H6B	107.5
C5—O2—C2—O1	−6.53 (16)	C2—C1—C3—C4	173.80 (9)
C5—O2—C2—C1	170.56 (8)	C1—C3—C4—C6	−126.34 (13)
C3—C1—C2—O1	9.95 (18)	C2—O2—C5—C6^i	−118.97 (11)
C3—C1—C2—O2	−167.09 (9)	C3—C4—C6—C5^i	71.46 (14)

Symmetry code: (i) −x+1, −y+2, −z.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
C4—H4A···O1^ii	0.97	2.67	3.544 (2)	150

Symmetry code: (ii) −x+2, −y+1, −z.