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Acta Crystallogr Sect E Struct Rep Online. 2009 June 1; 65(Pt 6): o1368–o1369.
Published online 2009 May 23. doi:  10.1107/S1600536809018455
PMCID: PMC2969627

(7R,8S,8aS)-8-Hydr­oxy-7-phenyl­perhydro­indolizin-3-one

Abstract

In the title compound, C14H17NO2, the six-membered ring of the indolizine system adopts a chair conformation. In the crystal, mol­ecules form chains parallel to the b axis via inter­molecular O—H(...)O hydrogen bonds. The absolute mol­ecular configuration was assigned from the synthesis.

Related literature

For industrial uses of indolizines, see: Jaung & Jung (2003 [triangle]); Rotaru et al. (2005 [triangle]); Delattre et al. (2005 [triangle]); Kelin et al. (2001 [triangle]). For biological uses, see: Nash et al. (1988 [triangle]); Molyneux & James (1982 [triangle]); Harrell (1970 [triangle]); Ruprecht et al. (1989 [triangle]); Liu et al. (2007 [triangle]); Smith et al. (2007 [triangle]); Gupta et al. (2003 [triangle]); Rosseels et al. (1982 [triangle]); Oslund et al. (2008 [triangle]); Ostby et al. (2000 [triangle]). For synthesis of indolizines, see: Chuprakov & Gevorgyan (2007 [triangle]); Yan & Liu (2007 [triangle]). For the synthesis methods used, see: Šafář et al. (2009 [triangle]). For structures related to the title compound, see: Švorc et al. (2009 [triangle]). For comparison of mol­ecular parameters, see: Camus et al. (2003 [triangle]); Lokaj et al. (1999 [triangle]); Brown & Corbridge (1954 [triangle]); Pedersen (1967 [triangle]). For a general analysis of puckering, see: Cremer & Pople (1975 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-65-o1368-scheme1.jpg

Experimental

Crystal data

  • C14H17NO2
  • M r = 231.29
  • Orthorhombic, An external file that holds a picture, illustration, etc.
Object name is e-65-o1368-efi1.jpg
  • a = 11.4164 (3) Å
  • b = 6.6372 (2) Å
  • c = 15.5118 (4) Å
  • V = 1175.38 (6) Å3
  • Z = 4
  • Mo Kα radiation
  • μ = 0.09 mm−1
  • T = 298 K
  • 0.60 × 0.56 × 0.13 mm

Data collection

  • Oxford Diffraction Gemini R CCD diffractometer
  • Absorption correction: analytical (Clark & Reid, 1995 [triangle]) T min = 0.901, T max = 0.989
  • 26298 measured reflections
  • 1632 independent reflections
  • 1128 reflections with I > 2σ(I)
  • R int = 0.023

Refinement

  • R[F 2 > 2σ(F 2)] = 0.035
  • wR(F 2) = 0.101
  • S = 1.03
  • 1632 reflections
  • 157 parameters
  • 1 restraint
  • H-atom parameters constrained
  • Δρmax = 0.17 e Å−3
  • Δρmin = −0.12 e Å−3

Data collection: CrysAlis CCD (Oxford Diffraction, 2006 [triangle]); cell refinement: CrysAlis RED (Oxford Diffraction, 2006 [triangle]); data reduction: CrysAlis RED; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: DIAMOND (Brandenburg, 2001 [triangle]); software used to prepare material for publication: enCIFer (Allen et al., 2004 [triangle]).

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536809018455/bg2260sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536809018455/bg2260Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Acknowledgments

The authors thank the Grant Agency of the Slovak Republic (grant Nos. 1/0161/08 and 1/0817/08) and Structural Funds, Interreg IIIA, for financial support in purchasing the diffractometer, and the Development Agency under contract No. APVV-0210-07.

supplementary crystallographic information

Comment

Heterocycles are involved in a wide range of biologically important chemical reactions in living organisms, and therefore they form one of the most important and well investigated classes of organic compounds. One group of heterocycles, indolizines, has received much scientific attention during the recent years. They are known for their use as synthetic dyes (Jaung & Jung, 2003), fluorescent materials (Rotaru et al., 2005; Delattre et al., 2005) and also as key intermediates for the synthesis of indolizine based molecules (Kelin et al., 2001). Indolizines both synthetic and natural have also been ascribed with a number of useful biological activities such as antibacterial, antiviral, antiinflammatory (Nash et al., 1988; Molyneux & James, 1982), testosterone-3&-reductase inhibitors, 5-HT4 receptor antagonists, CNS depressants (Harrell et al., 1970), anti-HIV (Ruprecht et al., 1989), anti-cancer (Liu et al., 2007; Smith et al., 2007) and have been used for treating cardiovascular ailments (Gupta et al., 2003). For instance, aminoalkyloxybenzenesulfonylindolizine compounds such as fantofarone and butoprozine have been used for the treatment of hypertension, arrhythmia and angina pectoris (Rosseels et al., 1982). Several oxygenated indolizines have been shown to prevent, due to their strong anti-oxidative effects, the initiation of oxidation processes that lead to DNA damage (Oslund et al., 2008; Ostby et al., 2000). Consequently, synthesis of indolizines have attracted considerable attention and a number of synthetic methodologies have been developed for a variety of indolizines, making use of in particular, transition metal catalyzed reactions (Chuprakov & Gevorgyan, 2007; Yan & Liu, 2007). In addition, indolizines and their derivatives are important in the field of material science owing to their unique photophysical properties.

Based on these facts and in continutation of our interest in developing simple and efficient routes for the synthesis of novel indolizine derivatives, we report here the synthesis and molecular and crystal structure of the title compound, (I) (Fig. 1). A similar analysis of its enantiomer (the stereochemistry of atom C6 was confirmed as R) has already been published (Švorc et al., 2009). The absolute configuration of (I) was established by the synthesis and is depicted in the scheme and Fig. 1. The expected stereochemistry of atoms C5, C6 and C7 was confirmed as S, S and R, respectively (Fig. 1). The central six-membered N-heterocyclic ring is not planar and adopts a chair conformation (Cremer & Pople, 1975). A calculation of least-squares planes shows that this ring is puckered in such a manner that the four atoms C5, C6, C8 and C9 are coplanar to within 0.010 (2) Å, while atoms N1 and C7 are displaced from this plane on opposite sides, with out-of-plane displacements of -0.555 (2) and 0.711 (2) Å, respectively. The phenyl ring attached to the indolizine ring system is planar (mean deviation is 0.009 (2) Å). The N1—C5 and N1—C9 bonds are approximately equivalent (See supplementary material) and both are much longer than the N1—C2 bond. Moreover, the N1 atom is sp2 hybridized, as evidenced by the sum of the valence angles around it [359.9 (2)°]. These data are consistent with conjugation of the lone-pair electrons on N1 with the adjacent carbonyl and agree with literature values for simple amides (Brown & Corbridge, 1954; Pedersen, 1967). The bond length of the carbonyl group C2═O1 is 1.236 (2) Å, respectively, is somewhat longer than typical carbonyl bonds. This may be due to the fact that atom O1 participates as acceptor in intermolecular hydrogen bonds with atom O2 as a donor. These intermolecular O—H···O hydrogen bonds link the molecules of (I) into extended chains, which run parallel to the b axis (Fig. 2) and help to stabilize the crystal structure of the compound. Bond lengths and angles in the indolizine ring system are in good agreement with values from the literature (Camus et al., 2003; Lokaj et al., 1999).

Experimental

The title compound (7R,8S,8aS)-8-hydroxy-7-phenylhexahydroindolizin-3(5H)-one was prepared according literature procedures of Šafář et al. (2009).

Refinement

All H atoms were placed in geometrically idealized positions and constrained to ride on their parent atoms, with C—H distances in the range 0.93–0.98 Å and O—H distance 0.85 Å and Uiso set at 1.2Ueq of the parent atom. The absolute configuration could not be reliably determined for this compound using Mo radiation, and has been assigned according to the synthesis; Friedel pairs have been merged.

Figures

Fig. 1.
Molecular structure of (I) with the atomic numbering scheme. Displacement ellipsoids are drawn at the 50% probability level (Brandenburg, 2001).
Fig. 2.
A packing of the molecule of (I), viewed along the b axis.

Crystal data

C14H17NO2F(000) = 496
Mr = 231.29Dx = 1.307 Mg m3
Orthorhombic, Pca21Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2c -2acCell parameters from 13180 reflections
a = 11.4164 (3) Åθ = 3.3–29.4°
b = 6.6372 (2) ŵ = 0.09 mm1
c = 15.5118 (4) ÅT = 298 K
V = 1175.38 (6) Å3Block, white
Z = 40.60 × 0.56 × 0.13 mm

Data collection

Oxford Diffraction Gemini R CCD diffractometer1632 independent reflections
Radiation source: fine-focus sealed tube1128 reflections with I > 2σ(I)
graphiteRint = 0.023
Detector resolution: 10.4340 pixels mm-1θmax = 29.4°, θmin = 3.6°
Rotation method data acquisition using ω and [var phi] scansh = −15→15
Absorption correction: analytical (Clark & Reid, 1995)k = −9→9
Tmin = 0.901, Tmax = 0.989l = −20→21
26298 measured reflections

Refinement

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-atom parameters constrained
wR(F2) = 0.101w = 1/[σ2(Fo2) + (0.0644P)2 + 0.0334P] where P = (Fo2 + 2Fc2)/3
S = 1.03(Δ/σ)max < 0.001
1632 reflectionsΔρmax = 0.17 e Å3
157 parametersΔρmin = −0.12 e Å3
1 restraintExtinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.014 (4)

Special details

Experimental. face-indexed (CrysAlis RED; Oxford Diffraction, 2006)
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 (Å2)

xyzUiso*/Ueq
C20.2640 (2)−0.3204 (3)0.32882 (13)0.0425 (5)
C30.21718 (19)−0.1773 (3)0.26133 (17)0.0490 (5)
H3A0.1398−0.12960.27730.059*
H3B0.2121−0.24380.20580.059*
C40.3027 (2)−0.0043 (4)0.25750 (16)0.0590 (6)
H4A0.26260.12270.26700.071*
H4B0.34090.00030.20170.071*
C50.3932 (2)−0.0428 (3)0.32948 (15)0.0466 (5)
H50.4708−0.05780.30330.056*
C60.40010 (17)0.1156 (3)0.40092 (13)0.0400 (4)
H60.43400.23930.37710.048*
C70.47970 (18)0.0382 (3)0.47386 (13)0.0421 (5)
H70.55580.00750.44780.051*
C80.4309 (2)−0.1608 (3)0.50890 (16)0.0514 (6)
H8A0.4814−0.21000.55450.062*
H8B0.3537−0.13780.53320.062*
C90.4226 (2)−0.3184 (3)0.43821 (15)0.0557 (6)
H9A0.5006−0.35690.41970.067*
H9B0.3832−0.43750.46000.067*
C100.50152 (16)0.1935 (3)0.54318 (14)0.0407 (5)
C110.42606 (19)0.2235 (4)0.61193 (16)0.0507 (5)
H110.35820.14640.61590.061*
C120.4494 (2)0.3654 (4)0.67466 (16)0.0580 (6)
H120.39760.38330.72030.070*
C130.5498 (2)0.4808 (4)0.66972 (17)0.0599 (7)
H130.56620.57540.71220.072*
C140.6248 (2)0.4553 (4)0.60216 (17)0.0623 (7)
H140.69190.53430.59820.075*
C150.60156 (19)0.3120 (4)0.53928 (16)0.0501 (5)
H150.65380.29510.49380.060*
N10.35736 (17)−0.2359 (3)0.36550 (12)0.0473 (4)
O10.22237 (14)−0.4869 (2)0.34724 (11)0.0545 (5)
O20.28771 (12)0.1598 (2)0.43433 (11)0.0496 (4)
H20.26470.26730.41460.074*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
C20.0503 (12)0.0381 (10)0.0391 (11)0.0064 (9)0.0004 (9)−0.0066 (9)
C30.0507 (13)0.0483 (11)0.0480 (12)0.0040 (9)−0.0032 (10)0.0014 (10)
C40.0858 (18)0.0477 (12)0.0436 (12)−0.0088 (11)−0.0148 (13)0.0042 (10)
C50.0585 (13)0.0404 (10)0.0408 (10)−0.0013 (9)−0.0015 (10)0.0023 (9)
C60.0488 (11)0.0331 (10)0.0382 (10)−0.0015 (8)0.0012 (9)0.0038 (8)
C70.0395 (10)0.0449 (12)0.0419 (11)0.0035 (8)−0.0023 (9)−0.0003 (9)
C80.0681 (15)0.0384 (11)0.0478 (11)0.0032 (10)−0.0163 (11)0.0054 (9)
C90.0736 (15)0.0366 (11)0.0570 (14)0.0078 (9)−0.0211 (12)0.0039 (10)
C100.0405 (10)0.0417 (11)0.0397 (10)0.0017 (8)−0.0059 (9)0.0024 (8)
C110.0523 (11)0.0496 (12)0.0501 (12)0.0022 (9)0.0080 (11)−0.0004 (10)
C120.0783 (16)0.0509 (12)0.0447 (12)0.0132 (12)0.0045 (12)−0.0045 (11)
C130.0818 (17)0.0480 (12)0.0500 (13)0.0058 (11)−0.0209 (13)−0.0055 (11)
C140.0621 (14)0.0556 (14)0.0693 (16)−0.0098 (11)−0.0195 (14)0.0004 (12)
C150.0453 (11)0.0587 (13)0.0464 (12)−0.0024 (10)−0.0031 (10)0.0035 (10)
N10.0593 (11)0.0359 (9)0.0465 (9)0.0005 (8)−0.0100 (8)0.0014 (8)
O10.0640 (11)0.0413 (8)0.0582 (11)−0.0047 (6)−0.0065 (8)0.0027 (7)
O20.0456 (8)0.0486 (8)0.0546 (9)0.0083 (6)0.0023 (7)0.0085 (7)

Geometric parameters (Å, °)

C2—O11.237 (2)C8—C91.518 (3)
C2—N11.332 (3)C8—H8A0.9700
C2—C31.511 (3)C8—H8B0.9700
C3—C41.508 (3)C9—N11.458 (3)
C3—H3A0.9700C9—H9A0.9700
C3—H3B0.9700C9—H9B0.9700
C4—C51.542 (3)C10—C111.385 (3)
C4—H4A0.9700C10—C151.388 (3)
C4—H4B0.9700C11—C121.380 (3)
C5—N11.457 (3)C11—H110.9300
C5—C61.530 (3)C12—C131.380 (4)
C5—H50.9800C12—H120.9300
C6—O21.414 (2)C13—C141.364 (4)
C6—C71.540 (3)C13—H130.9300
C6—H60.9800C14—C151.388 (3)
C7—C101.510 (3)C14—H140.9300
C7—C81.533 (3)C15—H150.9300
C7—H70.9800O2—H20.8200
O1—C2—N1125.78 (19)C9—C8—H8A109.4
O1—C2—C3125.9 (2)C7—C8—H8A109.4
N1—C2—C3108.33 (17)C9—C8—H8B109.4
C2—C3—C4106.09 (18)C7—C8—H8B109.4
C2—C3—H3A110.5H8A—C8—H8B108.0
C4—C3—H3A110.5N1—C9—C8109.40 (16)
C2—C3—H3B110.5N1—C9—H9A109.8
C4—C3—H3B110.5C8—C9—H9A109.8
H3A—C3—H3B108.7N1—C9—H9B109.8
C3—C4—C5106.18 (18)C8—C9—H9B109.8
C3—C4—H4A110.5H9A—C9—H9B108.2
C5—C4—H4A110.5C11—C10—C15117.7 (2)
C3—C4—H4B110.5C11—C10—C7122.92 (19)
C5—C4—H4B110.5C15—C10—C7119.4 (2)
H4A—C4—H4B108.7C10—C11—C12121.4 (2)
N1—C5—C6109.98 (17)C10—C11—H11119.3
N1—C5—C4103.63 (18)C12—C11—H11119.3
C6—C5—C4116.45 (19)C13—C12—C11120.0 (2)
N1—C5—H5108.8C13—C12—H12120.0
C6—C5—H5108.8C11—C12—H12120.0
C4—C5—H5108.8C14—C13—C12119.7 (2)
O2—C6—C5111.15 (17)C14—C13—H13120.2
O2—C6—C7109.59 (16)C12—C13—H13120.2
C5—C6—C7109.49 (16)C13—C14—C15120.3 (2)
O2—C6—H6108.9C13—C14—H14119.9
C5—C6—H6108.9C15—C14—H14119.9
C7—C6—H6108.9C10—C15—C14121.0 (2)
C10—C7—C6113.12 (15)C10—C15—H15119.5
C10—C7—C8113.31 (18)C14—C15—H15119.5
C6—C7—C8109.48 (17)C2—N1—C5115.52 (17)
C10—C7—H7106.8C2—N1—C9125.54 (18)
C6—C7—H7106.8C5—N1—C9118.92 (18)
C8—C7—H7106.8C6—O2—H2109.5
C9—C8—C7111.1 (2)
O1—C2—C3—C4−175.3 (2)C8—C7—C10—C15139.5 (2)
N1—C2—C3—C45.1 (2)C15—C10—C11—C12−0.3 (3)
C2—C3—C4—C5−4.7 (2)C7—C10—C11—C12179.3 (2)
C3—C4—C5—N12.8 (2)C10—C11—C12—C13−0.1 (4)
C3—C4—C5—C6−118.0 (2)C11—C12—C13—C140.7 (4)
N1—C5—C6—O2−67.5 (2)C12—C13—C14—C15−1.0 (4)
C4—C5—C6—O250.0 (2)C11—C10—C15—C140.0 (3)
N1—C5—C6—C753.7 (2)C7—C10—C15—C14−179.6 (2)
C4—C5—C6—C7171.18 (18)C13—C14—C15—C100.6 (3)
O2—C6—C7—C10−63.7 (2)O1—C2—N1—C5176.9 (2)
C5—C6—C7—C10174.18 (17)C3—C2—N1—C5−3.5 (2)
O2—C6—C7—C863.7 (2)O1—C2—N1—C9−4.6 (3)
C5—C6—C7—C8−58.4 (2)C3—C2—N1—C9175.0 (2)
C10—C7—C8—C9−174.06 (18)C6—C5—N1—C2125.53 (19)
C6—C7—C8—C958.6 (2)C4—C5—N1—C20.4 (2)
C7—C8—C9—N1−52.9 (3)C6—C5—N1—C9−53.1 (3)
C6—C7—C10—C1185.3 (2)C4—C5—N1—C9−178.2 (2)
C8—C7—C10—C11−40.0 (3)C8—C9—N1—C2−126.4 (2)
C6—C7—C10—C15−95.1 (2)C8—C9—N1—C552.1 (3)

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
O2—H2···O1i0.822.002.807 (2)170

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

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: BG2260).

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