Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S0108270100009793/fr1293sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S0108270100009793/fr1293Isup2.hkl |
CCDC reference: 152628
Bicyclo[3.3.1]nonan-9-one, purchased from Aldrich Chemical Co., Milwaukee, Wisconsin, USA, was subjected to Baeyer-Villiger oxidation by the procedure of Zalikowski et al. (1980), and the resulting lactone (m.p. 416 K) was saponified. The hydroxy acid obtained showed a tendency to relactonize during the subsequent Jones oxidation, necessitating extractive separation of (I) from the lactone. Purification and crystallization from Et2O-hexane gave (I) (m.p. 352 K).
All H atoms were found in electron-density difference maps but were placed in calculated positions, with O—H 0.82 Å and C—H 0.97–0.98 Å, and allowed to refine as riding models with isotropic displacement parameters set at 120% of their respective C atoms for the ordered molecule; the isotropic displacement parameter for the carboxyl H was allowed to refine for the ordered molecule. For the disordered molecule, H atoms were generated for the disordered C3'' and C7'' positions, as well as for the geometric positions on C2', C4', C6' and C8'; these H atoms were allowed to ride on their respective C atoms, with their isotropic displacement parameters fixed at 0.08 Å2. The disordered pair of carboxyl-H atoms was also found in electron-density difference maps and refined in idealized positions to an occupancy ratio of 0.66:0.34 (6).
Data collection: XSCANS (Siemens, 1996); cell refinement: XSCANS; data reduction: XSCANS; program(s) used to solve structure: SHELXTL (Sheldrick, 1997); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.
C9H14O3 | F(000) = 368 |
Mr = 170.20 | Dx = 1.239 Mg m−3 |
Triclinic, P1 | Melting point: 352 K |
a = 6.7449 (8) Å | Mo Kα radiation, λ = 0.71073 Å |
b = 9.8755 (13) Å | Cell parameters from 25 reflections |
c = 13.878 (2) Å | θ = 10.7–15.2° |
α = 81.586 (10)° | µ = 0.09 mm−1 |
β = 86.189 (10)° | T = 293 K |
γ = 88.519 (9)° | Block, colorless |
V = 912.3 (2) Å3 | 0.54 × 0.38 × 0.20 mm |
Z = 4 |
Siemens P4 diffractometer | 2100 reflections with I > 2σ(I) |
Radiation source: normal-focus sealed tube | Rint = 0.031 |
Graphite monochromator | θmax = 25.0°, θmin = 2.1° |
2θ/θ scans | h = −7→8 |
Absorption correction: numerical (SHELXTL; Sheldrick, 1997) | k = −11→11 |
Tmin = 0.97, Tmax = 0.98 | l = 0→16 |
4078 measured reflections | 3 standard reflections every 97 reflections |
3190 independent reflections | intensity decay: −3.3% |
Refinement on F2 | Secondary atom site location: difference Fourier map |
Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
R[F2 > 2σ(F2)] = 0.067 | H atoms treated by a mixture of independent and constrained refinement |
wR(F2) = 0.178 | w = 1/[σ2(Fo2) + (0.0611P)2 + 0.8272P] where P = (Fo2 + 2Fc2)/3 |
S = 1.02 | (Δ/σ)max = 0.02 |
3190 reflections | Δρmax = 0.27 e Å−3 |
234 parameters | Δρmin = −0.28 e Å−3 |
0 restraints | Extinction correction: SHELXTL (Sheldrick, 1997), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
Primary atom site location: structure-invariant direct methods | Extinction coefficient: 0.041 (5) |
C9H14O3 | γ = 88.519 (9)° |
Mr = 170.20 | V = 912.3 (2) Å3 |
Triclinic, P1 | Z = 4 |
a = 6.7449 (8) Å | Mo Kα radiation |
b = 9.8755 (13) Å | µ = 0.09 mm−1 |
c = 13.878 (2) Å | T = 293 K |
α = 81.586 (10)° | 0.54 × 0.38 × 0.20 mm |
β = 86.189 (10)° |
Siemens P4 diffractometer | 2100 reflections with I > 2σ(I) |
Absorption correction: numerical (SHELXTL; Sheldrick, 1997) | Rint = 0.031 |
Tmin = 0.97, Tmax = 0.98 | 3 standard reflections every 97 reflections |
4078 measured reflections | intensity decay: −3.3% |
3190 independent reflections |
R[F2 > 2σ(F2)] = 0.067 | 0 restraints |
wR(F2) = 0.178 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.02 | Δρmax = 0.27 e Å−3 |
3190 reflections | Δρmin = −0.28 e Å−3 |
234 parameters |
Experimental. Crystal mounted on glass fiber using epoxy cement |
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. |
x | y | z | Uiso*/Ueq | Occ. (<1) | |
O1 | −0.2589 (4) | 0.1370 (3) | 0.9205 (2) | 0.0684 (8) | |
O2 | 0.0525 (4) | 0.5523 (2) | 0.60202 (15) | 0.0562 (7) | |
O3 | −0.0317 (4) | 0.3413 (2) | 0.58442 (15) | 0.0557 (7) | |
C1 | 0.0104 (5) | 0.3824 (3) | 0.7450 (2) | 0.0401 (7) | |
C2 | −0.0450 (5) | 0.4954 (3) | 0.8074 (2) | 0.0499 (9) | |
C3 | −0.2091 (6) | 0.4562 (4) | 0.8862 (2) | 0.0563 (9) | |
C4 | −0.1578 (6) | 0.3421 (3) | 0.9685 (2) | 0.0552 (9) | |
C5 | −0.1196 (5) | 0.2060 (3) | 0.9342 (2) | 0.0466 (8) | |
C6 | 0.0890 (5) | 0.1548 (3) | 0.9195 (2) | 0.0509 (9) | |
C7 | 0.2412 (5) | 0.2587 (4) | 0.8724 (2) | 0.0533 (9) | |
C8 | 0.2138 (5) | 0.3128 (4) | 0.7653 (2) | 0.0536 (9) | |
C9 | 0.0122 (5) | 0.4353 (3) | 0.6371 (2) | 0.0415 (7) | |
O1' | 0.8575 (5) | 0.8203 (3) | 0.8392 (2) | 0.0894 (10) | |
O2' | 0.5155 (5) | 0.6736 (3) | 0.48547 (19) | 0.0722 (8) | |
O3' | 0.5734 (4) | 0.5221 (2) | 0.61585 (18) | 0.0598 (7) | |
C1' | 0.5959 (5) | 0.7567 (3) | 0.6315 (2) | 0.0452 (8) | |
C2' | 0.3959 (6) | 0.7896 (5) | 0.6818 (4) | 0.0829 (15) | |
C3' | 0.3931 (9) | 0.8129 (12) | 0.7828 (5) | 0.064 (3) | 0.600 (14) |
C3'' | 0.391 (2) | 0.8942 (18) | 0.7538 (12) | 0.080 (4)* | 0.400 (14) |
C4' | 0.5299 (7) | 0.8984 (6) | 0.8227 (4) | 0.0947 (17) | |
C5' | 0.7456 (5) | 0.8977 (3) | 0.7941 (2) | 0.0503 (9) | |
C6' | 0.8205 (7) | 0.9939 (5) | 0.7098 (3) | 0.0785 (13) | |
C7' | 0.7417 (18) | 0.9987 (9) | 0.6111 (5) | 0.061 (2) | 0.600 (14) |
C7'' | 0.855 (3) | 0.9423 (17) | 0.6198 (8) | 0.065 (4) | 0.400 (14) |
C8' | 0.6981 (7) | 0.8786 (4) | 0.5698 (3) | 0.0710 (12) | |
C9' | 0.5615 (5) | 0.6450 (3) | 0.5717 (2) | 0.0469 (8) | |
H1 | −0.0911 | 0.3119 | 0.7597 | 0.048* | |
H3 | −0.0288 | 0.3746 | 0.5267 | 0.084* | |
H2A | 0.0723 | 0.5184 | 0.8380 | 0.060* | |
H2B | −0.0871 | 0.5765 | 0.7651 | 0.060* | |
H3A | −0.3231 | 0.4281 | 0.8554 | 0.068* | |
H3B | −0.2488 | 0.5372 | 0.9151 | 0.068* | |
H4A | −0.0407 | 0.3676 | 0.9982 | 0.066* | |
H4B | −0.2667 | 0.3335 | 1.0182 | 0.066* | |
H6A | 0.0877 | 0.0819 | 0.8796 | 0.061* | |
H6B | 0.1334 | 0.1147 | 0.9826 | 0.061* | |
H7A | 0.3726 | 0.2170 | 0.8776 | 0.064* | |
H7B | 0.2357 | 0.3356 | 0.9088 | 0.064* | |
H8A | 0.2312 | 0.2371 | 0.7280 | 0.064* | |
H8B | 0.3173 | 0.3781 | 0.7421 | 0.064* | |
H1' | 0.6846 | 0.7195 | 0.6824 | 0.080* | |
H2' | 0.4582 | 0.6088 | 0.4697 | 0.080* | 0.34 (6) |
H3' | 0.5279 | 0.4697 | 0.5826 | 0.080* | 0.66 (6) |
H2'A | 0.3406 | 0.8707 | 0.6441 | 0.080* | 0.600 (14) |
H2'B | 0.3073 | 0.7148 | 0.6786 | 0.080* | 0.600 (14) |
H2'C | 0.3390 | 0.7038 | 0.7131 | 0.080* | 0.400 (14) |
H2'D | 0.3090 | 0.8275 | 0.6312 | 0.080* | 0.400 (14) |
H3'A | 0.4025 | 0.7230 | 0.8213 | 0.080* | 0.600 (14) |
H3'B | 0.2611 | 0.8483 | 0.7981 | 0.080* | 0.600 (14) |
H3'C | 0.3918 | 0.9838 | 0.7145 | 0.080* | 0.400 (14) |
H3'D | 0.2628 | 0.8856 | 0.7896 | 0.080* | 0.400 (14) |
H4'A | 0.5163 | 0.8747 | 0.8931 | 0.080* | 0.600 (14) |
H4'B | 0.4825 | 0.9922 | 0.8077 | 0.080* | 0.600 (14) |
H4'C | 0.5081 | 0.8232 | 0.8754 | 0.080* | 0.400 (14) |
H4'D | 0.5018 | 0.9818 | 0.8506 | 0.080* | 0.400 (14) |
H6'A | 0.9627 | 0.9775 | 0.7022 | 0.080* | 0.600 (14) |
H6'B | 0.8024 | 1.0850 | 0.7276 | 0.080* | 0.600 (14) |
H6'C | 0.7285 | 1.0713 | 0.7018 | 0.080* | 0.400 (14) |
H6'D | 0.9462 | 1.0282 | 0.7254 | 0.080* | 0.400 (14) |
H7'A | 0.6201 | 1.0533 | 0.6115 | 0.080* | 0.600 (14) |
H7'B | 0.8362 | 1.0504 | 0.5651 | 0.080* | 0.600 (14) |
H7'C | 0.9618 | 0.8747 | 0.6292 | 0.080* | 0.400 (14) |
H7'D | 0.9085 | 1.0175 | 0.5732 | 0.080* | 0.400 (14) |
H8'A | 0.8228 | 0.8449 | 0.5426 | 0.080* | 0.600 (14) |
H8'B | 0.6165 | 0.9080 | 0.5153 | 0.080* | 0.600 (14) |
H8'C | 0.7619 | 0.8481 | 0.5118 | 0.080* | 0.400 (14) |
H8'D | 0.5972 | 0.9463 | 0.5486 | 0.080* | 0.400 (14) |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.0707 (18) | 0.0580 (16) | 0.0773 (18) | −0.0179 (13) | −0.0075 (14) | −0.0081 (13) |
O2 | 0.0826 (17) | 0.0489 (14) | 0.0360 (12) | −0.0208 (12) | −0.0106 (11) | 0.0038 (10) |
O3 | 0.0883 (18) | 0.0438 (13) | 0.0354 (12) | −0.0060 (12) | −0.0081 (12) | −0.0037 (10) |
C1 | 0.0513 (19) | 0.0365 (16) | 0.0313 (15) | −0.0038 (13) | −0.0047 (13) | 0.0008 (12) |
C2 | 0.073 (2) | 0.0360 (17) | 0.0399 (17) | −0.0003 (16) | −0.0115 (16) | 0.0002 (13) |
C3 | 0.072 (2) | 0.051 (2) | 0.0467 (19) | 0.0091 (18) | 0.0005 (18) | −0.0135 (16) |
C4 | 0.074 (2) | 0.055 (2) | 0.0362 (17) | −0.0046 (18) | 0.0050 (17) | −0.0078 (15) |
C5 | 0.064 (2) | 0.0436 (18) | 0.0312 (16) | −0.0119 (16) | −0.0054 (15) | 0.0017 (13) |
C6 | 0.069 (2) | 0.0427 (18) | 0.0396 (18) | 0.0016 (16) | −0.0157 (16) | 0.0031 (14) |
C7 | 0.053 (2) | 0.056 (2) | 0.0499 (19) | 0.0026 (16) | −0.0177 (16) | 0.0021 (16) |
C8 | 0.059 (2) | 0.053 (2) | 0.0458 (19) | 0.0009 (17) | −0.0035 (16) | 0.0026 (15) |
C9 | 0.0480 (18) | 0.0419 (18) | 0.0341 (16) | −0.0018 (14) | −0.0065 (14) | −0.0017 (14) |
O1' | 0.125 (3) | 0.0735 (19) | 0.077 (2) | 0.0298 (18) | −0.0466 (19) | −0.0234 (16) |
O2' | 0.110 (2) | 0.0559 (16) | 0.0558 (16) | −0.0219 (15) | −0.0243 (15) | −0.0124 (12) |
O3' | 0.0750 (17) | 0.0439 (14) | 0.0645 (15) | −0.0089 (12) | −0.0195 (13) | −0.0134 (12) |
C1' | 0.0438 (18) | 0.0430 (18) | 0.0519 (19) | −0.0006 (14) | −0.0139 (15) | −0.0120 (15) |
C2' | 0.046 (2) | 0.102 (3) | 0.116 (4) | −0.006 (2) | 0.000 (2) | −0.071 (3) |
C3' | 0.040 (3) | 0.101 (7) | 0.046 (4) | −0.014 (4) | 0.011 (3) | 0.000 (4) |
C4' | 0.077 (3) | 0.128 (4) | 0.095 (3) | −0.026 (3) | 0.020 (3) | −0.074 (3) |
C5' | 0.062 (2) | 0.0461 (19) | 0.0476 (19) | −0.0047 (17) | −0.0105 (17) | −0.0190 (16) |
C6' | 0.096 (3) | 0.078 (3) | 0.065 (3) | −0.040 (2) | −0.020 (2) | −0.010 (2) |
C7' | 0.075 (6) | 0.051 (4) | 0.057 (4) | −0.018 (4) | −0.007 (4) | −0.005 (3) |
C7'' | 0.080 (10) | 0.068 (8) | 0.046 (6) | −0.039 (7) | 0.005 (6) | −0.006 (5) |
C8' | 0.103 (3) | 0.052 (2) | 0.059 (2) | −0.018 (2) | −0.021 (2) | −0.0037 (18) |
C9' | 0.0454 (19) | 0.046 (2) | 0.052 (2) | −0.0046 (15) | −0.0092 (15) | −0.0125 (15) |
O1—C5 | 1.216 (4) | C6—H6A | 0.9700 |
O2—C9 | 1.216 (4) | C6—H6B | 0.9700 |
O3—C9 | 1.314 (4) | C7—H7A | 0.9700 |
C1—C9 | 1.512 (4) | C7—H7B | 0.9700 |
C1—C2 | 1.534 (4) | C8—H8A | 0.9700 |
C1—C8 | 1.542 (5) | C8—H8B | 0.9700 |
C2—C3 | 1.519 (5) | O2'—H2' | 0.8200 |
C3—C4 | 1.533 (5) | O3'—H3' | 0.8200 |
C4—C5 | 1.501 (5) | C1'—H1' | 0.9800 |
C5—C6 | 1.494 (5) | C2'—H2'A | 0.9700 |
C6—C7 | 1.518 (5) | C2'—H2'B | 0.9700 |
C7—C8 | 1.525 (4) | C2'—H2'C | 0.9700 |
O1'—C5' | 1.200 (4) | C2'—H2'D | 0.9700 |
O2'—C9' | 1.247 (4) | C3'—H3'A | 0.9700 |
O3'—C9' | 1.280 (4) | C3'—H3'B | 0.9700 |
C1'—C9' | 1.505 (4) | C3'—H4'C | 1.5613 |
C1'—C8' | 1.523 (5) | C3''—H3'C | 0.9700 |
C1'—C2' | 1.527 (5) | C3''—H3'D | 0.9700 |
C2'—C3' | 1.453 (7) | C4'—H4'A | 0.9700 |
C2'—C3'' | 1.537 (13) | C4'—H4'B | 0.9700 |
C3'—C4' | 1.454 (9) | C4'—H4'C | 0.9700 |
C3''—C4' | 1.385 (13) | C4'—H4'D | 0.9702 |
C4'—C5' | 1.483 (5) | C6'—H6'A | 0.9700 |
C5'—C6' | 1.465 (5) | C6'—H6'B | 0.9700 |
C6'—C7'' | 1.420 (12) | C6'—H6'C | 0.9701 |
C6'—C7' | 1.496 (9) | C6'—H6'D | 0.9700 |
C7'—C8' | 1.436 (8) | C7'—H6'C | 1.5334 |
C7''—C8' | 1.505 (13) | C7'—H7'A | 0.9700 |
O3—H3 | 0.8200 | C7'—H7'B | 0.9700 |
C1—H1 | 0.9800 | C7'—H8'D | 1.4961 |
C2—H2A | 0.9700 | C7''—H7'C | 0.9700 |
C2—H2B | 0.9700 | C7''—H7'D | 0.9700 |
C3—H3A | 0.9700 | C8'—H8'A | 0.9700 |
C3—H3B | 0.9700 | C8'—H8'B | 0.9700 |
C4—H4A | 0.9700 | C8'—H8'C | 0.9700 |
C4—H4B | 0.9700 | C8'—H8'D | 0.9700 |
C9—O3—H3 | 109.5 | C1'—C2'—H2'D | 107.5 |
C9—C1—C2 | 111.9 (2) | C3''—C2'—H2'D | 105.7 |
C9—C1—C8 | 107.8 (3) | H2'A—C2'—H2'D | 32.3 |
C2—C1—C8 | 113.9 (3) | H2'B—C2'—H2'D | 76.9 |
C3—C2—C1 | 113.8 (3) | H2'C—C2'—H2'D | 107.0 |
C2—C3—C4 | 116.2 (3) | C2'—C3'—H3'A | 105.9 |
C5—C4—C3 | 113.1 (3) | C4'—C3'—H3'A | 105.9 |
O1—C5—C6 | 120.4 (3) | C2'—C3'—H3'B | 105.9 |
O1—C5—C4 | 119.7 (3) | C4'—C3'—H3'B | 105.9 |
C6—C5—C4 | 119.8 (3) | H3'A—C3'—H3'B | 106.2 |
C5—C6—C7 | 116.9 (3) | C2'—C3'—H4'C | 149.3 |
C6—C7—C8 | 114.8 (3) | C4'—C3'—H4'C | 37.3 |
C7—C8—C1 | 114.8 (3) | H3'A—C3'—H4'C | 70.6 |
O2—C9—O3 | 123.2 (3) | H3'B—C3'—H4'C | 104.3 |
O2—C9—C1 | 123.8 (3) | C4'—C3''—H3'C | 106.2 |
O3—C9—C1 | 113.1 (3) | C2'—C3''—H3'C | 106.2 |
C9'—C1'—C8' | 111.4 (3) | C4'—C3''—H3'D | 106.2 |
C9'—C1'—C2' | 107.1 (3) | C2'—C3''—H3'D | 106.2 |
C8'—C1'—C2' | 114.9 (3) | H3'C—C3''—H3'D | 106.4 |
C3'—C2'—C1' | 117.8 (4) | C3''—C4'—H4'A | 129.9 |
C3'—C2'—C3'' | 32.6 (5) | C3'—C4'—H4'A | 106.9 |
C1'—C2'—C3'' | 117.9 (6) | C5'—C4'—H4'A | 106.9 |
C2'—C3'—C4' | 125.8 (6) | C3''—C4'—H4'B | 75.2 |
C4'—C3''—C2' | 124.5 (10) | C3'—C4'—H4'B | 106.9 |
C3''—C4'—C3' | 34.4 (6) | C5'—C4'—H4'B | 106.9 |
C3''—C4'—C5' | 120.6 (7) | H4'A—C4'—H4'B | 106.7 |
C3'—C4'—C5' | 121.6 (4) | C3''—C4'—H4'C | 109.6 |
O1'—C5'—C6' | 120.4 (4) | C3'—C4'—H4'C | 77.4 |
O1'—C5'—C4' | 120.8 (4) | C5'—C4'—H4'C | 106.6 |
C6'—C5'—C4' | 118.8 (4) | H4'A—C4'—H4'C | 36.2 |
C7''—C6'—C5' | 117.1 (6) | H4'B—C4'—H4'C | 136.5 |
C7''—C6'—C7' | 37.5 (6) | C3''—C4'—H4'D | 106.3 |
C5'—C6'—C7' | 122.1 (4) | C3'—C4'—H4'D | 128.7 |
C8'—C7'—C6' | 123.4 (7) | C5'—C4'—H4'D | 106.5 |
C6'—C7''—C8' | 123.9 (12) | H4'A—C4'—H4'D | 71.9 |
C7'—C8'—C7'' | 37.2 (5) | H4'B—C4'—H4'D | 36.7 |
C7'—C8'—C1' | 121.2 (4) | H4'C—C4'—H4'D | 106.5 |
C7''—C8'—C1' | 114.6 (6) | C7''—C6'—H6'A | 73.8 |
O2'—C9'—O3' | 123.1 (3) | C5'—C6'—H6'A | 106.8 |
O2'—C9'—C1' | 120.5 (3) | C7'—C6'—H6'A | 106.8 |
O3'—C9'—C1' | 116.3 (3) | C7''—C6'—H6'B | 134.0 |
C9—C1—H1 | 107.7 | C5'—C6'—H6'B | 106.8 |
C2—C1—H1 | 107.7 | C7'—C6'—H6'B | 106.8 |
C8—C1—H1 | 107.7 | H6'A—C6'—H6'B | 106.7 |
C3—C2—H2A | 108.8 | C7''—C6'—H6'C | 109.7 |
C1—C2—H2A | 108.8 | C5'—C6'—H6'C | 107.9 |
C3—C2—H2B | 108.8 | C7'—C6'—H6'C | 73.4 |
C1—C2—H2B | 108.8 | H6'A—C6'—H6'C | 137.8 |
H2A—C2—H2B | 107.7 | H6'B—C6'—H6'C | 39.8 |
C2—C3—H3A | 108.2 | C7''—C6'—H6'D | 106.8 |
C4—C3—H3A | 108.2 | C5'—C6'—H6'D | 107.8 |
C2—C3—H3B | 108.2 | C7'—C6'—H6'D | 127.6 |
C4—C3—H3B | 108.2 | H6'A—C6'—H6'D | 38.4 |
H3A—C3—H3B | 107.4 | H6'B—C6'—H6'D | 69.8 |
C5—C4—H4A | 109.0 | H6'C—C6'—H6'D | 107.1 |
C3—C4—H4A | 109.0 | C8'—C7'—H6'C | 147.1 |
C5—C4—H4B | 109.0 | C6'—C7'—H6'C | 37.3 |
C3—C4—H4B | 109.0 | C8'—C7'—H7'A | 106.5 |
H4A—C4—H4B | 107.8 | C6'—C7'—H7'A | 106.5 |
C5—C6—H6A | 108.1 | H6'C—C7'—H7'A | 71.1 |
C7—C6—H6A | 108.1 | C8'—C7'—H7'B | 106.5 |
C5—C6—H6B | 108.1 | C6'—C7'—H7'B | 106.5 |
C7—C6—H6B | 108.1 | H6'C—C7'—H7'B | 105.6 |
H6A—C6—H6B | 107.3 | H7'A—C7'—H7'B | 106.5 |
C6—C7—H7A | 108.6 | C8'—C7'—H8'D | 38.6 |
C8—C7—H7A | 108.6 | C6'—C7'—H8'D | 148.3 |
C6—C7—H7B | 108.6 | H6'C—C7'—H8'D | 136.1 |
C8—C7—H7B | 108.6 | H7'A—C7'—H8'D | 70.2 |
H7A—C7—H7B | 107.5 | H7'B—C7'—H8'D | 104.6 |
C7—C8—H8A | 108.6 | C6'—C7''—H7'C | 106.3 |
C1—C8—H8A | 108.6 | C8'—C7''—H7'C | 106.3 |
C7—C8—H8B | 108.6 | C6'—C7''—H7'D | 106.4 |
C1—C8—H8B | 108.6 | C8'—C7''—H7'D | 106.4 |
H8A—C8—H8B | 107.5 | H7'C—C7''—H7'D | 106.4 |
C9'—O2'—H2' | 109.5 | C7'—C8'—H8'A | 107.0 |
C9'—O3'—H3' | 109.5 | C7''—C8'—H8'A | 75.3 |
C9'—C1'—H1' | 107.7 | C1'—C8'—H8'A | 107.0 |
C8'—C1'—H1' | 107.7 | C7'—C8'—H8'B | 107.0 |
C2'—C1'—H1' | 107.7 | C7''—C8'—H8'B | 135.7 |
C3'—C2'—H2'A | 107.9 | C1'—C8'—H8'B | 107.0 |
C1'—C2'—H2'A | 107.9 | H8'A—C8'—H8'B | 106.8 |
C3''—C2'—H2'A | 77.7 | C7'—C8'—H8'C | 127.3 |
C3'—C2'—H2'B | 107.9 | C7''—C8'—H8'C | 107.3 |
C1'—C2'—H2'B | 107.9 | C1'—C8'—H8'C | 108.4 |
C3''—C2'—H2'B | 130.0 | H8'A—C8'—H8'C | 36.6 |
H2'A—C2'—H2'B | 107.2 | H8'B—C8'—H8'C | 71.6 |
C3'—C2'—H2'C | 80.9 | C7'—C8'—H8'D | 74.1 |
C1'—C2'—H2'C | 107.6 | C7''—C8'—H8'D | 110.4 |
C3''—C2'—H2'C | 110.6 | C1'—C8'—H8'D | 108.5 |
H2'A—C2'—H2'C | 133.1 | H8'A—C8'—H8'D | 136.8 |
H2'B—C2'—H2'C | 31.8 | H8'B—C8'—H8'D | 38.8 |
C3'—C2'—H2'D | 129.2 | H8'C—C8'—H8'D | 107.5 |
C9—C1—C2—C3 | 129.6 (3) | C2'—C3'—C4'—C3'' | 57.7 (11) |
C8—C1—C2—C3 | −107.8 (3) | C2'—C3'—C4'—C5' | −41.5 (13) |
C1—C2—C3—C4 | 66.8 (4) | C3''—C4'—C5'—O1' | −130.9 (10) |
C2—C3—C4—C5 | −65.5 (4) | C3'—C4'—C5'—O1' | −90.4 (7) |
C3—C4—C5—O1 | −79.5 (4) | C3''—C4'—C5'—C6' | 49.4 (11) |
C3—C4—C5—C6 | 102.1 (4) | C3'—C4'—C5'—C6' | 89.8 (8) |
O1—C5—C6—C7 | 140.6 (3) | O1'—C5'—C6'—C7'' | 81.0 (11) |
C4—C5—C6—C7 | −41.0 (4) | C4'—C5'—C6'—C7'' | −99.2 (10) |
C5—C6—C7—C8 | −68.4 (4) | O1'—C5'—C6'—C7' | 124.0 (7) |
C6—C7—C8—C1 | 58.3 (4) | C4'—C5'—C6'—C7' | −56.2 (8) |
C9—C1—C8—C7 | 177.4 (3) | C7''—C6'—C7'—C8' | 52.4 (10) |
C2—C1—C8—C7 | 52.6 (4) | C5'—C6'—C7'—C8' | −41.4 (13) |
C2—C1—C9—O2 | 30.3 (4) | C5'—C6'—C7''—C8' | 58.7 (19) |
C8—C1—C9—O2 | −95.7 (4) | C7'—C6'—C7''—C8' | −49.5 (13) |
C2—C1—C9—O3 | −150.6 (3) | C6'—C7'—C8'—C7'' | −48.8 (10) |
C8—C1—C9—O3 | 83.4 (3) | C6'—C7'—C8'—C1' | 41.5 (13) |
C9'—C1'—C2'—C3' | 138.7 (6) | C6'—C7''—C8'—C7' | 53.0 (14) |
C8'—C1'—C2'—C3' | −96.9 (7) | C6'—C7''—C8'—C1' | −56.9 (18) |
C9'—C1'—C2'—C3'' | 175.7 (9) | C9'—C1'—C8'—C7' | 178.6 (7) |
C8'—C1'—C2'—C3'' | −59.9 (10) | C2'—C1'—C8'—C7' | 56.5 (8) |
C1'—C2'—C3'—C4' | 46.1 (12) | C9'—C1'—C8'—C7'' | −139.8 (9) |
C3''—C2'—C3'—C4' | −53.1 (11) | C2'—C1'—C8'—C7'' | 98.1 (10) |
C3'—C2'—C3''—C4' | 55.7 (13) | C8'—C1'—C9'—O2' | −37.0 (4) |
C1'—C2'—C3''—C4' | −43.0 (19) | C2'—C1'—C9'—O2' | 89.5 (4) |
C2'—C3''—C4'—C3' | −51.8 (11) | C8'—C1'—C9'—O3' | 146.1 (3) |
C2'—C3''—C4'—C5' | 50.6 (19) | C2'—C1'—C9'—O3' | −87.4 (4) |
Experimental details
Crystal data | |
Chemical formula | C9H14O3 |
Mr | 170.20 |
Crystal system, space group | Triclinic, P1 |
Temperature (K) | 293 |
a, b, c (Å) | 6.7449 (8), 9.8755 (13), 13.878 (2) |
α, β, γ (°) | 81.586 (10), 86.189 (10), 88.519 (9) |
V (Å3) | 912.3 (2) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.09 |
Crystal size (mm) | 0.54 × 0.38 × 0.20 |
Data collection | |
Diffractometer | Siemens P4 diffractometer |
Absorption correction | Numerical (SHELXTL; Sheldrick, 1997) |
Tmin, Tmax | 0.97, 0.98 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 4078, 3190, 2100 |
Rint | 0.031 |
(sin θ/λ)max (Å−1) | 0.595 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.067, 0.178, 1.02 |
No. of reflections | 3190 |
No. of parameters | 234 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.27, −0.28 |
Computer programs: XSCANS (Siemens, 1996), XSCANS, SHELXTL (Sheldrick, 1997), SHELXTL.
O2—C9 | 1.216 (4) | O2'—C9' | 1.247 (4) |
O3—C9 | 1.314 (4) | O3'—C9' | 1.280 (4) |
O2—C9—C1 | 123.8 (3) | O2'—C9'—C1' | 120.5 (3) |
O3—C9—C1 | 113.1 (3) | O3'—C9'—C1' | 116.3 (3) |
Because ketone and acid carbonyls have similar basicities and may compete as hydrogen-bond acceptors, the keto acids on which our X-ray crystallographic studies focus have an expanded repertoire of solid state hydrogen-bonding motifs compared with monofunctional carboxylic acids. The commonest hydrogen-bonding mode is acid dimerization without ketone involvement, but carboxyl-to-ketone chains (catemers) constitute a sizeable minority of cases. The remaining motifs are all relatively rare: intramolecular hydrogen bonds, acid-to-acid catemers and carboxyl-to-ketone dimers. We have previously referenced numerous examples and discussed factors that appear to govern the choice of hydrogen-bonding mode (Brunskill et al., 1999; Thompson et al., 1999). The title compound, (I), belongs to the category of ε-keto acids, which, besides dimers, includes at least five instances of carboxyl-to-ketone catemers and one of an internal hydrogen bond. \sch
Fig. 1 shows the asymmetric unit with its numbering. Both molecules, (I) and (I'), adopt transoid `boat-chair' conformations, in which, excluding attached atoms, the C8 ring skeleton has symmetry visualizable as a mirror plane passing through C3 and C7. The boat-chair conformation is the one generally found to be of lowest energy in a variety of studies (Eliel et al., 1994). The carboxyl group in both (I) and (I') is aimed outward from the ring, `equatorially', so that its potential cross-ring interaction with the ketone function is avoided and that juxtaposition involves not the carboxyl group but rather H1A. Because the ketone and carboxyl groups are arranged dissymmetrically on the ring, the resulting conformations are chiral, although the compound has no inherent chirality. Also contributing to the conformational chirality is the twist of the carboxyl group about C1—C9, described by the O2—C9—C1—C2 and O2—C9—C1—C8 torsion angles, which in (I) are 30.3 (4) and −95.7 (4)°, respectively; the corresponding angles in (I') are 89.5 (4) and −37.0 (4)°, respectively. Although the carboxyl group in (I) is highly ordered, (I') displays significant partial averaging of carboxyl C—O bond lengths and C—C—O angles, and, while adhering generally to the conformation adopted by (I), also displays a conformational disordering of the ring.
The conformational disorder in (I') is produced by an `up-down' disordering of the remote ends of the boat-chair system, C3' and C7'. The overall ratio found in difference maps for the conformational contributors to (I') is 60:40 (1), indicated in Fig. 1 by dark bonds for the major and `ghost' bonds for the minor component. Separate single-atom refinement of C3' versus its disorder counterpart C3'' gave an occupancy ratio of 69:31 (1) query, while the same treatment for C7' and C7'' produced a ratio of 59:41 (2). The similarity of these two ratios, almost within experimental error, strongly implies that the conformations involved in (I') are coupled, i.e. entirely of the `boat-chair' type, such that when C3' is up, C7' is down and vice versa, and not cisoid ones, in which these atoms might sometimes be `both up' (chair-chair) or `both down' (boat-boat) simultaneously. Significantly higher enthalpies have been estimated for the latter two species than for the boat-chair conformer (Eliel et al., 1994). In addition, substantial estimated interconversion barriers make it very probable that the observed disorder is static. Because some additional disorder in C3'' is detectable as high anisotropy in its displacement ellipsoid, the displacement parameter for C3'' was refined isotropically. With respect to the carbon skeleton alone the two species inhabiting the (I') site would be antipodal, but because of the twist of the carboxyl group the two are not symmetrically related.
Although not observed in catemers, disordering of carboxyl bond lengths and angles is common in carboxyl dimers (Leiserowitz, 1976). Significant partial averaging is found in (I'), where these C—O bond lengths are 1.247 (4) and 1.280 (4) Å, with angles of 120.5 (3) and 116.3 (3)°. Consistent with this disorder, partial carboxyl H atoms found in difference maps were refined to an occupancy ratio of 66:34 (6). In contrast, (I) is highly ordered, with values of 1.216 (4) and 1.314 (4) Å, and 123.8 (3)° and 113.1 (3)°, consistent with typical values of 1.21 and 1.31 Å, and 123 and 112°, cited for highly ordered dimeric carboxyls (Borthwick, 1980).
Fig. 2 shows the packing arrangement, which involves carboxyl dimers. Molecules of types (I) and (I') are not paired together; rather, each pairs centrosymmetrically with a second molecule of its own type, yielding dimers of two kinds at different crystallographic sites in the chosen cell. Molecule (I) forms highly ordered dimers centered on the bc cell face [O···O 2.658 (3) Å and O—H···O = 174°], while the dimers formed by (I') at (1/2,1/2,1/2) are disordered as described above [O···O 2.653 (3) Å and O—H···O = 165°]. Because the two disorder components of species (I') within the asymmetric unit are symmetrically unrelated, the resultant disorder in its dimers is not an enantiomeric transposition of d-l and l-d dimers, and it is even imaginable that individual dimers of (I') might be non-centrosymmetric. We have no specific information concerning this possibility, but we are inclined against it because of the centrosymmetry of the space group and the strict centrosymmetry observed for dimers of type (I).
Two intermolecular C=O···H—C close contacts were found for the ketone (O1) in molecule (I), involving H7A of a molecule of (I) translated in a (2.67 Å) and H4'D of a molecule of (I') (2.58 Å). There is a similar close contact for (I') between O1' and H6B in a molecule of (I) (2.65 Å). These contacts all lie within the 2.7 Å range often employed for non-bonded C—H···O packing interactions (Steiner, 1997). Using data compiled for a large number of such contacts, Steiner & Desiraju (1998) find significant statistical directionality even as far out as 3.0 Å, and conclude that these are legitimately viewed as `weak hydrogen bonds', with a greater contribution to packing forces than simple van der Waals attractions.
The solid-state (KBr) infrared spectrum of (I) has discrete C=O absorptions at 1720, 1711 and 1692 cm−1, all of which coalesce in CHCl3 solution to a single broader asymmetric peak centered at 1704 cm−1. Multiplicity of solid state C=O bands is often seen in structures with disorder in the carbonyl-bearing moieties (Lalancette et al., 1997).