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organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 64| Part 12| December 2008| Page o2292
doi:10.1107/S1600536808035691

(2RS,8aRS)-6-Oxo-1,2,3,4,6,7,8,8a-octa­hydro­naphthalene-2-carboxylic acid

Georgia Efthimiopoulos,a Roger A. Lalancettea and Hugh W. Thompsona*

aCarl A. Olson Memorial Laboratories, Department of Chemistry, Rutgers University, Newark, NJ 07102, USA
*Correspondence e-mail: rogerlal@andromeda.rutgers.edu

(Received 25 October 2008; accepted 30 October 2008; online 8 November 2008)

The title racemate, C11H14O3, aggregates in the crystal structure as acid-to-ketone O—H⋯O hydrogen-bonding catemers whose components are glide-related. The relative stereochemistry at the carboxyl group arises spontaneously during the synthesis. Two inter­molecular C—H⋯O=C close contacts were found, both involving the acid group.

Related literature

For background information, see: Borthwick (1980[Borthwick, P. W. (1980). Acta Cryst. B36, 628-632.]). For synthetic details see: Finnegan & Bachman (1965[Finnegan, R. A. & Bachman, P. L. (1965). J. Org. Chem. 30, 4145-4150.]); House et al. (1965[House, H. O., Trost, B. M., Magin, R. W., Carlson, R. G., Franck, R. W. & Rasmusson, G. H. (1965). J. Org. Chem. 30, 2513-2519.]). For information on weak hydrogen bonds, see: Steiner (1997[Steiner, T. (1997). Chem. Commun. pp. 727-734.]).

[Scheme 1]

Experimental

Crystal data

  • C11H14O3

  • Mr = 194.22

  • Monoclinic, P 21 /c

  • a = 6.2315 (11) Å

  • b = 9.2296 (16) Å

  • c = 17.234 (3) Å

  • β = 93.366 (3)°

  • V = 989.5 (3) Å3

  • Z = 4

  • Cu Kα radiation

  • μ = 0.77 mm−1

  • T = 100 (2) K

  • 0.36 × 0.31 × 0.22 mm
Data collection

  • Bruker SMART APEXII CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 2001[Sheldrick, G. M. (2001). SADABS. University of Göttingen, Germany.]) Tmin = 0.768, Tmax = 0.849

  • 7466 measured reflections

  • 1719 independent reflections

  • 1684 reflections with I > 2σ(I)

  • Rint = 0.028
Refinement

  • R[F2 > 2σ(F2)] = 0.035

  • wR(F2) = 0.088

  • S = 1.09

  • 1719 reflections

  • 131 parameters

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.22 e Å−3

  • Δρmin = −0.20 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A D⋯A D—H⋯A
O3—H3⋯O1i 0.888 (19) 1.79 (2) 2.6797 (13) 174.8 (17)
C2—H2⋯O2ii 1.00 2.40 3.3191 (15) 152
C7—H7A⋯O2iii 0.99 2.47 3.3708 (15) 151
Symmetry codes: (i) [x+1, -y+{\script{3\over 2}}, z-{\script{1\over 2}}]; (ii) [-x+1, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]; (iii) [x, -y+{\script{3\over 2}}, z+{\script{1\over 2}}].

Data collection: APEX2 (Bruker, 2006[Bruker (2006). APEX2. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2005[Bruker (2005). SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536808035691/lh2720sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536808035691/lh2720Isup2.hkl

checkCIF report


Comment top

Among ketocarboxylic acids, we have shown that the usually dominant dimerization can be disfavored by lowering molecular flexibility, as measured by the number of fully rotatable bonds present. Typically this results in increased occurrence of acid-to-ketone catemers, whose occurrence is also favored by fixed "anti-like" arrangements, in which carboxyl and ketone are aimed in opposite directions. In this context, we report here the title compound, (I), whose structure conforms to both of the above criteria.

Fig. 1 shows the asymmetric unit, whose only conformational options lie in the carboxyl side-chain, which is oriented [C1—C2—C9—O2 torsion angle = -37.96 (15)°] so as to minimize steric interactions with H atoms at C1 and C3.

The disordering of C—O bond lengths and C—C—O angles often seen in carboxyl dimers becomes impossible when the H-bonding mode precludes the required averaging mechanisms. Because (I) is not dimeric the distances and angles here are fully ordered and thus typical of those in highly ordered dimeric carboxyls (Borthwick, 1980).

Fig. 2 shows the packing of the cell, with extra molecules included to illustrate the acid-to-ketone H-bonding scheme. Each carboxylic acid is linked to the ketone in a molecule glide related in the c direction. Glide relationships for intra-chain units in catemers is far less common than screw-related schemes. Each of the four molecules in the chosen cell participates in a separate H-bonding chain and these pass through the cell in counterdirectional pairs related by centrosymmetry, with the chains advancing by one cell in a and one-half cell in c for each H bond.

We characterize the geometry of H bonding to carbonyls using a combination of the H···O=C angle and the H···O=C—C torsion angle. These describe the approach of the H atom to the receptor O in terms of its deviation from, respectively, C=O axiality (ideal = 120°) and planarity with the carbonyl (ideal = 0°). In (I), these angles are 131.0 (6) & 0.6 (8)°.

Within the 2.6 Å range we standardly survey for C—H···O packing interactions (Steiner, 1997), two intermolecular close contacts were found, both involving O2, the carboxyl carbonyl (see table).

Related literature top

For background information, see: Borthwick (1980). For synthetic details see: Finnegan & Bachman (1965); House et al. (1965). F for information on weak hydrogen bonds, see: Steiner (1997).

Experimental top

Compound (I) was synthesized by the method of Finnegan & Bachman (1965); crystallization from ethyl acetate yielded material suitable for X-ray, mp 418 K. The C2/C8a stereochemistry clearly represents the stabler of the two epimers possible and probably arises as the result of equilibrations during the synthesis (House et al., 1965).

The solid-state (KBr) infrared spectrum of (I) has C=O absorptions at 1721 & 1640 cm-1, with a peak separation typical of the shifts seen in catemers, due, respectively, to removal of H bonding from the acid C=O and addition of H bonding to the ketone; an alkene peak appears at 1616 cm-1. In CHCl3 solution, where dimers predominate, these bands appear, respectively, at 1708, 1666 and 1622 cm-1.

Refinement top

All H atoms for (I) were found in electron-density difference maps. The positional parameters for the carboxyl H were allowed to refine but the Uiso(H) was held at 1.5Ueq(O). The methylene, methine and vinyl Hs were placed in geometrically idealized positions and constrained to ride on their parent C atoms with C–H distances of 0.99, 1.00 & 0.95 Å, respectively, and Uiso(H) = 1.2Ueq(C).

Computing details top

Data collection: APEX2 (Bruker, 2006); cell refinement: APEX2 (Bruker, 2006); data reduction: SAINT (Bruker, 2005); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The asymmetric unit of (I), with its numbering. Displacement ellipsoids are drawn at the 40% probability level.
[Figure 2] Fig. 2. A partial packing diagram with extracellular molecules, illustrating the centrosymmetrically related pairs of acid-to-ketone H-bonding chains passing through the cell. All carbon-bound H atoms are removed for clarity. Displacement ellipsoids are drawn at the 40% probability level.
(2RS,8aRS)-6-Oxo-1,2,3,4,6,7,8,8a-octahydronaphthalene-2- carboxylic acid top
Crystal data top
C11H14O3F(000) = 416
Mr = 194.22Dx = 1.304 Mg m−3
Monoclinic, P21/cMelting point: 418 K
Hall symbol: -P 2ybcCu Kα radiation, λ = 1.54178 Å
a = 6.2315 (11) ÅCell parameters from 7006 reflections
b = 9.2296 (16) Åθ = 4.8–67.1°
c = 17.234 (3) ŵ = 0.77 mm−1
β = 93.366 (3)°T = 100 K
V = 989.5 (3) Å3Parallelepiped, colourless
Z = 40.36 × 0.31 × 0.22 mm
Data collection top
Bruker SMART CCD APEXII area-detector
diffractometer		1719 independent reflections
Radiation source: fine-focus sealed tube1684 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.028
ϕ and ω scansθmax = 67.3°, θmin = 5.1°
Absorption correction: multi-scan
(SADABS; Sheldrick, 2001)		h = −7→7
Tmin = 0.769, Tmax = 0.849k = −11→10
7466 measured reflectionsl = −20→20
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.035H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.088 w = 1/[σ2(Fo2) + (0.0417P)2 + 0.4167P]
where P = (Fo2 + 2Fc2)/3
S = 1.09(Δ/σ)max < 0.001
1719 reflectionsΔρmax = 0.22 e Å−3
131 parametersΔρmin = −0.20 e Å−3
0 restraintsExtinction correction: SHELXTL (Sheldrick, 2004), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.0064 (8)
Crystal data top
C11H14O3V = 989.5 (3) Å3
Mr = 194.22Z = 4
Monoclinic, P21/cCu Kα radiation
a = 6.2315 (11) ŵ = 0.77 mm−1
b = 9.2296 (16) ÅT = 100 K
c = 17.234 (3) Å0.36 × 0.31 × 0.22 mm
β = 93.366 (3)°
Data collection top
Bruker SMART CCD APEXII area-detector
diffractometer		1719 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 2001)		1684 reflections with I > 2σ(I)
Tmin = 0.769, Tmax = 0.849Rint = 0.028
7466 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0350 restraints
wR(F2) = 0.088H atoms treated by a mixture of independent and constrained refinement
S = 1.09Δρmax = 0.22 e Å−3
1719 reflectionsΔρmin = −0.20 e Å−3
131 parameters
Special details top

Experimental. crystal mounted on a Cryoloop using Paratone-N

Geometry. All e.s.d.'s (except for 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 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 (Å2) top
xyzUiso*/Ueq
O1−0.28896 (14)0.72032 (11)0.52340 (5)0.0292 (3)
C10.36320 (19)0.76724 (13)0.32544 (7)0.0191 (3)
H1A0.26970.84590.30380.023*
H1B0.50530.81000.34050.023*
O20.41479 (13)0.84304 (9)0.16676 (5)0.0217 (2)
C20.39130 (18)0.65372 (13)0.26199 (7)0.0176 (3)
H20.49690.57880.28160.021*
O30.61028 (15)0.64301 (10)0.15353 (5)0.0281 (3)
H30.652 (3)0.689 (2)0.1116 (11)0.042*
C30.17383 (19)0.58079 (14)0.24029 (7)0.0199 (3)
H3A0.07160.65370.21780.024*
H3B0.19320.50520.20060.024*
C40.08193 (19)0.51220 (13)0.31220 (7)0.0200 (3)
H4A−0.06310.47350.29780.024*
H4B0.17440.42990.32970.024*
C4A0.06671 (19)0.61740 (13)0.37828 (7)0.0175 (3)
C5−0.11075 (19)0.62502 (14)0.41883 (7)0.0198 (3)
H5−0.23460.57200.40090.024*
C6−0.1206 (2)0.71159 (14)0.48942 (7)0.0210 (3)
C70.0842 (2)0.78214 (14)0.52003 (7)0.0223 (3)
H7A0.16810.71270.55340.027*
H7B0.04980.86680.55230.027*
C80.2190 (2)0.83140 (14)0.45355 (7)0.0219 (3)
H8A0.14150.90910.42390.026*
H8B0.35660.87200.47540.026*
C8A0.26523 (18)0.70674 (13)0.39857 (7)0.0181 (3)
H8A10.37440.64210.42570.022*
C90.47226 (18)0.72473 (13)0.19025 (7)0.0176 (3)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0244 (5)0.0408 (6)0.0233 (5)0.0023 (4)0.0086 (4)−0.0059 (4)
C10.0194 (6)0.0190 (6)0.0190 (6)−0.0020 (5)0.0018 (5)−0.0008 (5)
O20.0236 (5)0.0198 (5)0.0219 (4)0.0021 (3)0.0031 (3)0.0030 (4)
C20.0171 (6)0.0179 (6)0.0181 (6)0.0011 (4)0.0028 (4)0.0012 (5)
O30.0348 (5)0.0249 (5)0.0264 (5)0.0084 (4)0.0165 (4)0.0053 (4)
C30.0206 (6)0.0218 (6)0.0176 (6)−0.0016 (5)0.0040 (5)−0.0038 (5)
C40.0192 (6)0.0197 (6)0.0214 (6)−0.0029 (5)0.0046 (5)−0.0027 (5)
C4A0.0185 (6)0.0173 (6)0.0164 (6)0.0023 (5)0.0000 (4)0.0026 (5)
C50.0180 (6)0.0232 (6)0.0182 (6)0.0004 (5)0.0007 (5)−0.0003 (5)
C60.0227 (6)0.0231 (7)0.0175 (6)0.0046 (5)0.0029 (5)0.0028 (5)
C70.0266 (7)0.0237 (7)0.0167 (6)0.0021 (5)0.0016 (5)−0.0036 (5)
C80.0235 (6)0.0220 (6)0.0201 (6)−0.0013 (5)0.0016 (5)−0.0028 (5)
C8A0.0177 (6)0.0189 (6)0.0175 (6)0.0009 (5)0.0004 (5)0.0005 (5)
C90.0155 (6)0.0183 (6)0.0190 (6)−0.0012 (4)0.0008 (4)−0.0016 (5)
Geometric parameters (Å, º) top
O1—C61.2337 (15)C4—H4A0.9900
C1—C21.5319 (16)C4—H4B0.9900
C1—C8A1.5373 (16)C4A—C51.3443 (17)
C1—H1A0.9900C4A—C8A1.5106 (16)
C1—H1B0.9900C5—C61.4597 (17)
O2—C91.2114 (15)C5—H50.9500
C2—C91.5119 (16)C6—C71.5006 (17)
C2—C31.5395 (16)C7—C81.5290 (17)
C2—H21.0000C7—H7A0.9900
O3—C91.3315 (15)C7—H7B0.9900
O3—H30.888 (19)C8—C8A1.5287 (17)
C3—C41.5323 (16)C8—H8A0.9900
C3—H3A0.9900C8—H8B0.9900
C3—H3B0.9900C8A—H8A11.0000
C4—C4A1.5038 (17)
C2—C1—C8A113.85 (10)C4A—C5—C6122.56 (11)
C2—C1—H1A108.8C4A—C5—H5118.7
C8A—C1—H1A108.8C6—C5—H5118.7
C2—C1—H1B108.8O1—C6—C5120.66 (11)
C8A—C1—H1B108.8O1—C6—C7122.28 (11)
H1A—C1—H1B107.7C5—C6—C7117.00 (10)
C9—C2—C1110.17 (10)C6—C7—C8111.03 (10)
C9—C2—C3108.79 (9)C6—C7—H7A109.4
C1—C2—C3109.67 (9)C8—C7—H7A109.4
C9—C2—H2109.4C6—C7—H7B109.4
C1—C2—H2109.4C8—C7—H7B109.4
C3—C2—H2109.4H7A—C7—H7B108.0
C9—O3—H3110.2 (12)C8A—C8—C7111.88 (10)
C4—C3—C2110.47 (9)C8A—C8—H8A109.2
C4—C3—H3A109.6C7—C8—H8A109.2
C2—C3—H3A109.6C8A—C8—H8B109.2
C4—C3—H3B109.6C7—C8—H8B109.2
C2—C3—H3B109.6H8A—C8—H8B107.9
H3A—C3—H3B108.1C4A—C8A—C8111.88 (10)
C4A—C4—C3112.89 (10)C4A—C8A—C1111.57 (9)
C4A—C4—H4A109.0C8—C8A—C1109.47 (10)
C3—C4—H4A109.0C4A—C8A—H8A1107.9
C4A—C4—H4B109.0C8—C8A—H8A1107.9
C3—C4—H4B109.0C1—C8A—H8A1107.9
H4A—C4—H4B107.8O2—C9—O3122.57 (11)
C5—C4A—C4121.19 (11)O2—C9—C2123.90 (11)
C5—C4A—C8A122.59 (11)O3—C9—C2113.51 (10)
C4—C4A—C8A116.14 (10)
C8A—C1—C2—C9175.69 (9)C6—C7—C8—C8A−55.49 (14)
C8A—C1—C2—C355.97 (13)C5—C4A—C8A—C8−15.56 (16)
C9—C2—C3—C4−177.89 (10)C4—C4A—C8A—C8167.65 (10)
C1—C2—C3—C4−57.33 (13)C5—C4A—C8A—C1−138.58 (12)
C2—C3—C4—C4A53.90 (13)C4—C4A—C8A—C144.63 (14)
C3—C4—C4A—C5134.81 (12)C7—C8—C8A—C4A45.26 (13)
C3—C4—C4A—C8A−48.36 (14)C7—C8—C8A—C1169.47 (10)
C4—C4A—C5—C6171.69 (11)C2—C1—C8A—C4A−48.74 (13)
C8A—C4A—C5—C6−4.94 (18)C2—C1—C8A—C8−173.13 (9)
C4A—C5—C6—O1177.19 (12)C1—C2—C9—O2−37.96 (15)
C4A—C5—C6—C7−5.68 (17)C3—C2—C9—O282.29 (14)
O1—C6—C7—C8−147.35 (12)C1—C2—C9—O3143.64 (10)
C5—C6—C7—C835.57 (15)C3—C2—C9—O3−96.11 (12)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O3—H3···O1i0.888 (19)1.79 (2)2.6797 (13)174.8 (17)
C2—H2···O2ii1.002.403.3191 (15)152
C7—H7A···O2iii0.992.473.3708 (15)151
Symmetry codes: (i) x+1, −y+3/2, z−1/2; (ii) −x+1, y−1/2, −z+1/2; (iii) x, −y+3/2, z+1/2.

Experimental details

Crystal data
Chemical formulaC11H14O3
Mr194.22
Crystal system, space groupMonoclinic, P21/c
Temperature (K)100
a, b, c (Å)6.2315 (11), 9.2296 (16), 17.234 (3)
β (°) 93.366 (3)
V (Å3)989.5 (3)
Z4
Radiation typeCu Kα
µ (mm−1)0.77
Crystal size (mm)0.36 × 0.31 × 0.22
Data collection
DiffractometerBruker SMART CCD APEXII area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 2001)
Tmin, Tmax0.769, 0.849
No. of measured, independent and
observed [I > 2σ(I)] reflections		7466, 1719, 1684
Rint0.028
(sin θ/λ)max (Å−1)0.598
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.035, 0.088, 1.09
No. of reflections1719
No. of parameters131
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å−3)0.22, −0.20

Computer programs: APEX2 (Bruker, 2006), SAINT (Bruker, 2005), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O3—H3···O1i0.888 (19)1.79 (2)2.6797 (13)174.8 (17)
C2—H2···O2ii1.002.403.3191 (15)152
C7—H7A···O2iii0.992.473.3708 (15)151
Symmetry codes: (i) x+1, −y+3/2, z−1/2; (ii) −x+1, y−1/2, −z+1/2; (iii) x, −y+3/2, z+1/2.
 

Acknowledgements

The authors gratefully acknowledge support in the form of NSF-CRIF grant No. 0443538. HWT also thanks Professor Gree Loober Spoog for helpful discussions.

References

First citationBorthwick, P. W. (1980). Acta Cryst. B36, 628–632.  CrossRef CAS IUCr Journals Web of Science Google Scholar
 First citationBruker (2005). SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
 First citationBruker (2006). APEX2. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
 First citationFinnegan, R. A. & Bachman, P. L. (1965). J. Org. Chem. 30, 4145–4150.  CrossRef CAS PubMed Web of Science Google Scholar
 First citationHouse, H. O., Trost, B. M., Magin, R. W., Carlson, R. G., Franck, R. W. & Rasmusson, G. H. (1965). J. Org. Chem. 30, 2513–2519.  CrossRef CAS Web of Science Google Scholar
 First citationSheldrick, G. M. (2001). SADABS. University of Göttingen, Germany.  Google Scholar
 First citationSheldrick, G. M. (2008). Acta Cryst. A64, 112–122.  Web of Science CrossRef CAS IUCr Journals Google Scholar
 First citationSteiner, T. (1997). Chem. Commun. pp. 727–734.  CrossRef Web of Science Google Scholar

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Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 64| Part 12| December 2008| Page o2292
doi:10.1107/S1600536808035691
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