Both carboxyl groups in the title molecule, C9H12O4, have gauche orientations [relative to the (HOOC-)C-C(-COOH) bond] and participate in hydrogen bonds, linking the molecules into an infinite chain.
Supporting information
CCDC reference: 200777
Key indicators
- Single-crystal X-ray study
- T = 295 K
- Mean (C-C) = 0.002 Å
- R factor = 0.044
- wR factor = 0.113
- Data-to-parameter ratio = 14.1
checkCIF results
No syntax errors found
ADDSYM reports no extra symmetry
Data collection: SMART (Siemens, 1995); cell refinement: SMART; data reduction: SAINT (Siemens, 1995); program(s) used to solve structure: SHELXS86 (Sheldrick, 1990); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL (Bruker, 1998); software used to prepare material for publication: SHELXTL.
bicyclo[2.2.1]heptane-
exo-
cis-2,3-dicarboxylic acid
top
Crystal data top
C9H12O4 | F(000) = 784 |
Mr = 184.19 | Dx = 1.368 Mg m−3 |
Monoclinic, C2/c | Mo Kα radiation, λ = 0.71073 Å |
a = 15.327 (2) Å | Cell parameters from 443 reflections |
b = 11.503 (2) Å | θ = 10.2–20.8° |
c = 10.643 (2) Å | µ = 0.11 mm−1 |
β = 107.57 (1)° | T = 295 K |
V = 1788.9 (5) Å3 | Prism, colourless |
Z = 8 | 0.40 × 0.26 × 0.22 mm |
Data collection top
Siemens SMART 1K CCD area-detector diffractometer | 1895 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.030 |
Graphite monochromator | θmax = 29.0°, θmin = 2.3° |
Detector resolution: 8 pixels mm-1 | h = −17→20 |
ω scans | k = −15→15 |
6844 measured reflections | l = −14→14 |
2358 independent reflections | |
Refinement top
Refinement on F2 | Secondary atom site location: difference Fourier map |
Least-squares matrix: full | Hydrogen site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.044 | All H-atom parameters refined |
wR(F2) = 0.113 | w = 1/[σ2(Fo2) + (0.0351P)2 + 1.2379P] where P = (Fo2 + 2Fc2)/3 |
S = 1.10 | (Δ/σ)max < 0.001 |
2358 reflections | Δρmax = 0.26 e Å−3 |
167 parameters | Δρmin = −0.17 e Å−3 |
0 restraints | Extinction correction: SHELXL97, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
Primary atom site location: structure-invariant direct methods | Extinction coefficient: 0.0175 (12) |
Special details top
Experimental. The data collection nominally covered more than a hemisphere of reciprocal
space, by a combination of 4 sets of ω scans; each set at different φ and/or
2θ angles and each scan (15 s exposure) covering 0.3° in ω. Crystal to
detector distance 4.52 cm. Crystal decay was monitored by repeating 50 initial
frames at the end of data collection and comparing 112 duplicate reflections. |
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. |
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top | x | y | z | Uiso*/Ueq | |
C1 | 0.28662 (10) | 0.21617 (16) | 0.82808 (15) | 0.0461 (4) | |
H1 | 0.2852 (13) | 0.2597 (17) | 0.9044 (19) | 0.057 (5)* | |
C2 | 0.20857 (9) | 0.24928 (13) | 0.70414 (13) | 0.0364 (3) | |
H2 | 0.2223 (11) | 0.3203 (14) | 0.6617 (16) | 0.042 (4)* | |
C3 | 0.20419 (9) | 0.14329 (12) | 0.60976 (13) | 0.0360 (3) | |
H3 | 0.2193 (11) | 0.1681 (13) | 0.5296 (15) | 0.040 (4)* | |
C4 | 0.27957 (11) | 0.06231 (15) | 0.69545 (18) | 0.0486 (4) | |
H4 | 0.2725 (13) | −0.0185 (18) | 0.6611 (19) | 0.062 (5)* | |
C5 | 0.37253 (11) | 0.1166 (2) | 0.7035 (2) | 0.0605 (5) | |
H51 | 0.4220 (16) | 0.059 (2) | 0.747 (2) | 0.082 (7)* | |
H52 | 0.3776 (15) | 0.137 (2) | 0.616 (2) | 0.078 (7)* | |
C6 | 0.37689 (11) | 0.22366 (19) | 0.79305 (18) | 0.0565 (5) | |
H61 | 0.4283 (15) | 0.2176 (18) | 0.872 (2) | 0.071 (6)* | |
H62 | 0.3813 (14) | 0.2983 (19) | 0.7476 (19) | 0.064 (6)* | |
C7 | 0.27357 (12) | 0.08507 (17) | 0.83437 (17) | 0.0543 (5) | |
H71 | 0.3228 (15) | 0.0479 (17) | 0.902 (2) | 0.068 (6)* | |
H72 | 0.2138 (13) | 0.0620 (16) | 0.8476 (18) | 0.057 (5)* | |
C8 | 0.11836 (10) | 0.27697 (13) | 0.72779 (14) | 0.0394 (3) | |
C9 | 0.11375 (9) | 0.08057 (12) | 0.56364 (13) | 0.0370 (3) | |
O1 | 0.05313 (8) | 0.30401 (12) | 0.62254 (11) | 0.0558 (3) | |
H01 | −0.006 (2) | 0.305 (3) | 0.642 (3) | 0.124 (10)* | |
O2 | 0.10967 (8) | 0.27751 (12) | 0.83953 (11) | 0.0556 (3) | |
O3 | 0.08654 (9) | 0.06000 (12) | 0.43818 (11) | 0.0581 (4) | |
H03 | 0.029 (2) | 0.021 (2) | 0.415 (3) | 0.108 (9)* | |
O4 | 0.07213 (8) | 0.04906 (12) | 0.63960 (11) | 0.0584 (4) | |
Atomic displacement parameters (Å2) top | U11 | U22 | U33 | U12 | U13 | U23 |
C1 | 0.0348 (7) | 0.0667 (10) | 0.0328 (7) | −0.0098 (7) | 0.0044 (5) | 0.0004 (7) |
C2 | 0.0353 (7) | 0.0409 (7) | 0.0318 (6) | −0.0091 (6) | 0.0085 (5) | −0.0007 (5) |
C3 | 0.0331 (6) | 0.0414 (7) | 0.0347 (7) | −0.0075 (5) | 0.0119 (5) | 0.0004 (5) |
C4 | 0.0372 (8) | 0.0464 (9) | 0.0602 (10) | 0.0003 (6) | 0.0116 (7) | 0.0052 (7) |
C5 | 0.0338 (8) | 0.0809 (13) | 0.0666 (12) | 0.0001 (8) | 0.0146 (8) | 0.0041 (10) |
C6 | 0.0327 (8) | 0.0805 (13) | 0.0506 (9) | −0.0158 (8) | 0.0039 (7) | 0.0045 (9) |
C7 | 0.0384 (8) | 0.0699 (11) | 0.0498 (9) | −0.0024 (8) | 0.0061 (7) | 0.0243 (8) |
C8 | 0.0392 (7) | 0.0429 (8) | 0.0350 (7) | −0.0068 (6) | 0.0094 (6) | −0.0028 (6) |
C9 | 0.0366 (7) | 0.0387 (7) | 0.0353 (7) | −0.0070 (5) | 0.0105 (5) | −0.0012 (5) |
O1 | 0.0415 (6) | 0.0796 (9) | 0.0447 (6) | 0.0082 (6) | 0.0104 (5) | 0.0124 (6) |
O2 | 0.0439 (6) | 0.0870 (9) | 0.0367 (6) | −0.0062 (6) | 0.0133 (5) | −0.0108 (6) |
O3 | 0.0527 (7) | 0.0839 (9) | 0.0390 (6) | −0.0303 (6) | 0.0157 (5) | −0.0146 (6) |
O4 | 0.0529 (7) | 0.0826 (9) | 0.0413 (6) | −0.0347 (6) | 0.0165 (5) | −0.0052 (6) |
Geometric parameters (Å, º) top
C1—C7 | 1.525 (3) | C5—C6 | 1.546 (3) |
C1—C2 | 1.5373 (19) | C5—H51 | 1.01 (2) |
C1—C6 | 1.540 (2) | C5—H52 | 0.99 (2) |
C1—H1 | 0.960 (19) | C6—H61 | 0.97 (2) |
C2—C8 | 1.512 (2) | C6—H62 | 1.00 (2) |
C2—C3 | 1.568 (2) | C7—H71 | 0.97 (2) |
C2—H2 | 0.986 (17) | C7—H72 | 1.003 (19) |
C3—C9 | 1.5074 (18) | C8—O2 | 1.2361 (17) |
C3—C4 | 1.549 (2) | C8—O1 | 1.2942 (18) |
C3—H3 | 0.991 (16) | C9—O4 | 1.2261 (17) |
C4—C7 | 1.531 (3) | C9—O3 | 1.2948 (17) |
C4—C5 | 1.534 (2) | O1—H01 | 0.99 (3) |
C4—H4 | 0.99 (2) | O3—H03 | 0.95 (3) |
| | | |
C7—C1—C2 | 101.78 (12) | C4—C5—H51 | 108.5 (13) |
C7—C1—C6 | 101.84 (15) | C6—C5—H51 | 110.4 (13) |
C2—C1—C6 | 107.56 (13) | C4—C5—H52 | 112.3 (13) |
C7—C1—H1 | 116.3 (11) | C6—C5—H52 | 113.0 (14) |
C2—C1—H1 | 112.7 (12) | H51—C5—H52 | 109.3 (18) |
C6—C1—H1 | 115.2 (11) | C1—C6—C5 | 103.28 (14) |
C8—C2—C1 | 115.04 (12) | C1—C6—H61 | 110.1 (13) |
C8—C2—C3 | 113.95 (11) | C5—C6—H61 | 110.5 (13) |
C1—C2—C3 | 103.23 (12) | C1—C6—H62 | 111.3 (12) |
C8—C2—H2 | 103.6 (9) | C5—C6—H62 | 112.5 (12) |
C1—C2—H2 | 112.3 (9) | H61—C6—H62 | 109.1 (17) |
C3—C2—H2 | 108.9 (9) | C1—C7—C4 | 94.57 (12) |
C9—C3—C4 | 110.68 (12) | C1—C7—H71 | 112.6 (12) |
C9—C3—C2 | 115.98 (11) | C4—C7—H71 | 112.3 (13) |
C4—C3—C2 | 102.14 (12) | C1—C7—H72 | 113.9 (11) |
C9—C3—H3 | 106.7 (9) | C4—C7—H72 | 114.4 (11) |
C4—C3—H3 | 110.7 (9) | H71—C7—H72 | 108.6 (16) |
C2—C3—H3 | 110.6 (9) | O2—C8—O1 | 123.51 (14) |
C7—C4—C5 | 101.64 (14) | O2—C8—C2 | 122.05 (13) |
C7—C4—C3 | 102.37 (13) | O1—C8—C2 | 114.39 (12) |
C5—C4—C3 | 107.66 (14) | O4—C9—O3 | 123.80 (13) |
C7—C4—H4 | 119.0 (11) | O4—C9—C3 | 122.49 (12) |
C5—C4—H4 | 113.4 (11) | O3—C9—C3 | 113.67 (12) |
C3—C4—H4 | 111.6 (11) | C8—O1—H01 | 110.0 (16) |
C4—C5—C6 | 103.02 (14) | C9—O3—H03 | 109.5 (16) |
| | | |
O1—C8—C2—C3 | −60.67 (17) | C2—C3—C9—O3 | 133.33 (14) |
C8—C2—C3—C9 | −3.63 (17) | | |
Hydrogen-bond geometry (Å, º) top
D—H···A | D—H | H···A | D···A | D—H···A |
O1—H01···O2i | 0.99 (3) | 1.68 (3) | 2.6628 (16) | 168 (3) |
O3—H03···O4ii | 0.95 (3) | 1.69 (3) | 2.6378 (16) | 175 (3) |
Symmetry codes: (i) −x, y, −z+3/2; (ii) −x, −y, −z+1. |