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

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ISSN: 2056-9890

3-Hy­dr­oxy-1-(4-meth­­oxy­benz­yl)piperidin-2-one

aMolecular Sciences Institute, School of Chemistry, University of the Witwatersrand, PO Wits 2050, Johannesburg, South Africa
*Correspondence e-mail: joseph.michael@wits.ac.za

(Received 29 November 2012; accepted 3 December 2012; online 8 December 2012)

The title compound, C13H17NO3, adopts a conformation in which the aromatic ring and the mean plane of the piperidine ring are almost perpendicular to each other [dihedral angle = 79.25 (6)°]. The presence of the carbonyl group alters the conformation of the piperidine ring from a chair to a twisted half-chair conformation. In the crystal, pairs of strong O—H⋯O hydrogen bonds link the mol­ecules into inversion dimers. Weak C—H⋯O inter­actions extend the hydrogen-bonding network into three dimensions.

Related literature

For the use of related lactams in the synthesis of febrifugine analogues, see: Michael et al. (2006[Michael, J. P., de Koning, C. B. & Pienaar, D. P. (2006). Synlett, pp. 383-386.]). For information on the biological activity of febrifugine, a quinazoline alkaloid with potent anti­malarial activity, see: Murata et al. (1998[Murata, K., Takano, F., Fushiya, S. & Oshima, Y. (1998). J. Nat. Prod. 61, 729-733.]). For the use of chiral oxaziridines in asymmetric hy­droxy­lation, see: Davis et al. (1990[Davis, F. A., Sheppard, A. C., Chen, B.-C. & Haque, M. S. (1990). J. Am. Chem. Soc. 112, 6679-6690.]). For the conformation of six-membered rings, see: Boeyens (1978[Boeyens, J. C. A. (1978). J. Cryst. Mol. Struct. 8, 317-320.]).

[Scheme 1]

Experimental

Crystal data
  • C13H17NO3

  • Mr = 235.28

  • Monoclinic, P 21 /c

  • a = 12.980 (3) Å

  • b = 7.6143 (17) Å

  • c = 12.189 (3) Å

  • β = 90.497 (5)°

  • V = 1204.6 (5) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.09 mm−1

  • T = 173 K

  • 0.32 × 0.26 × 0.18 mm

Data collection
  • Bruker APEXII CCD diffractometer

  • 8378 measured reflections

  • 2895 independent reflections

  • 2271 reflections with I > 2σ(I)

  • Rint = 0.027

Refinement
  • R[F2 > 2σ(F2)] = 0.042

  • wR(F2) = 0.124

  • S = 1.08

  • 2895 reflections

  • 158 parameters

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

  • Δρmax = 0.52 e Å−3

  • Δρmin = −0.22 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O2—H2⋯O1i 0.96 (2) 1.84 (2) 2.7708 (16) 161.6 (19)
C6—H6B⋯O1ii 0.99 2.43 3.3142 (17) 148
C14—H14B⋯O2iii 0.98 2.52 3.449 (2) 158
Symmetry codes: (i) -x, -y, -z+1; (ii) [x, -y+{\script{1\over 2}}, z-{\script{1\over 2}}]; (iii) -x+1, -y, -z+1.

Data collection: APEX2 (Bruker, 2005[Bruker (2005). APEX2 and SAINT-NT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT-NT (Bruker, 2005[Bruker (2005). APEX2 and SAINT-NT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT-NT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]) and SCHAKAL99 (Keller, 1999[Keller, E. (1999). SCHAKAL99. University of Freiberg, Germany.]); software used to prepare material for publication: WinGX (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]) and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

Supporting information


Comment top

The title piperidinone was prepared as an early intermediate for the total synthesis of febrifugine, a quinazoline alkaloid with potent antimalarial activity (Murata et al., 1998). Ongoing investigations in our laboratories have made use of similar lactams for the synthesis of febrifugine analogues (Michael et al., 2006). It should be noted that, although the 3-hydroxy substituent was introduced by attempted asymmetric hydroxylation of the enolate of 1-(4-methoxybenzyl)piperidin-2-one with (+)-camphorsulfonyloxaziridine (Davis et al., 1990), partial racemization occurred; the crystals selected for analysis proved to be racemic.

The title organic compound (Fig. 1) adopts a conformation in which the aromatic ring and the piperidine ring are almost perpendicular to each other. Ring puckering analysis, as implemented in PLATON (Spek, 2009), indicates that the piperidine ring adopts a twisted half-chair conformation owing to the presence of the carbonyl group (Boeyens, 1978). Several hydrogen bonds exist in the structure (Table 1), with the most significant being an O—H···O hydrogen bond. These result in the formation of hydrogen bonded pairs of molecules which are related to each other by a center of inversion (Fig. 1). These molecules interact further through C—H···O interactions (Fig. 2) resulting in an extensive hydrogen bonding network of molecules.

Related literature top

For the use of related lactams in the synthesis of febrifugine analogues, see: Michael et al. (2006). For information on the biological activity of febrifugine, a quinazoline alkaloid with potent antimalarial activity, see: Murata et al. (1998). For the use of chiral oxaziridines in asymmetric hydroxylation, see: Davis et al. (1990). For the conformation of six-membered rings, see: Boeyens (1978).

Experimental top

To a solution of lithium hexamethyldisilazide, prepared from n-butyllithium (1.6 M in hexane, 1.83 ml, 2.93 mmol) and hexamethyldisilazane (0.63 ml) in THF (10 ml) at -70 °C was added a solution of 1-(4-methoxybenzyl)piperidin-2-one (322 mg, 1.47 mmol) in THF (20 ml). The solution was stirred at this temperature for 1 h, after which a solution of (+)-camphorsulfonyloxaziridine (0.67 g, 2.9 mmol) in THF (20 ml) was added dropwise. Stirring was maintained for a further 16 h at temperatures kept between -70 and -60 °C. The reaction was quenched by addition of saturated aqueous ammonium chloride solution (10 ml) and allowed to warm to ambient temperature. The organic components were extracted with dichloromethane (4 × 15 ml), the combined organic layers were washed with brine (20 ml), dried over MgSO4, and concentrated in vacuo. Purification by column chromatography on silica gel with hexane-ethyl acetate mixtures (9:1 to 1:1 v/v) yielded the title compound, which was recrystallized from hexane-ethyl acetate to yield the product as irregularly shaped colourless crystals (261 mg, 75%), m.p. 347–349 K.

Refinement top

All H atoms attached to C atoms were positioned geometrically, and allowed to ride on their parent atoms, with C—H bond lengths of 0.95 Å (Ar—H), 1.0 (CH), 0.99 Å (CH2) or 0.98 Å (CH3), and isotropic displacement parameters set to 1.2 (CH and CH2) or 1.5 times (CH3) the Ueq of the parent atom. The alcohol H atom (H2) was located from the difference map and refined freely with isotropic displacement parameter set to 1.5 times the Ueq of the parent atom O2.

Structure description top

The title piperidinone was prepared as an early intermediate for the total synthesis of febrifugine, a quinazoline alkaloid with potent antimalarial activity (Murata et al., 1998). Ongoing investigations in our laboratories have made use of similar lactams for the synthesis of febrifugine analogues (Michael et al., 2006). It should be noted that, although the 3-hydroxy substituent was introduced by attempted asymmetric hydroxylation of the enolate of 1-(4-methoxybenzyl)piperidin-2-one with (+)-camphorsulfonyloxaziridine (Davis et al., 1990), partial racemization occurred; the crystals selected for analysis proved to be racemic.

The title organic compound (Fig. 1) adopts a conformation in which the aromatic ring and the piperidine ring are almost perpendicular to each other. Ring puckering analysis, as implemented in PLATON (Spek, 2009), indicates that the piperidine ring adopts a twisted half-chair conformation owing to the presence of the carbonyl group (Boeyens, 1978). Several hydrogen bonds exist in the structure (Table 1), with the most significant being an O—H···O hydrogen bond. These result in the formation of hydrogen bonded pairs of molecules which are related to each other by a center of inversion (Fig. 1). These molecules interact further through C—H···O interactions (Fig. 2) resulting in an extensive hydrogen bonding network of molecules.

For the use of related lactams in the synthesis of febrifugine analogues, see: Michael et al. (2006). For information on the biological activity of febrifugine, a quinazoline alkaloid with potent antimalarial activity, see: Murata et al. (1998). For the use of chiral oxaziridines in asymmetric hydroxylation, see: Davis et al. (1990). For the conformation of six-membered rings, see: Boeyens (1978).

Computing details top

Data collection: APEX2 (Bruker, 2005); cell refinement: SAINT-NT (Bruker, 2005); data reduction: SAINT-NT (Bruker, 2005); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012) and SCHAKAL99 (Keller, 1999); software used to prepare material for publication: WinGX (Farrugia, 2012) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound, showing the hydrogen bonding to another molecule related by a center of inversion. Displacement ellipsoids are drawn at the 50% probability level.
[Figure 2] Fig. 2. O—H···O and C—H···O interactions in the crystal structure of the title compound, which result in an extensive hydrogen bonding network in three dimensions.
3-Hydroxy-1-(4-methoxybenzyl)piperidin-2-one top
Crystal data top
C13H17NO3F(000) = 504
Mr = 235.28Dx = 1.297 Mg m3
Monoclinic, P21/cMelting point: 347 K
Hall symbol: -P 2ybcMo Kα radiation, λ = 0.71073 Å
a = 12.980 (3) ÅCell parameters from 958 reflections
b = 7.6143 (17) Åθ = 3.5–28.3°
c = 12.189 (3) ŵ = 0.09 mm1
β = 90.497 (5)°T = 173 K
V = 1204.6 (5) Å3Irregular, colourless
Z = 40.32 × 0.26 × 0.18 mm
Data collection top
Bruker APEXII CCD
diffractometer
2271 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.027
Graphite monochromatorθmax = 28.0°, θmin = 3.1°
φ and ω scansh = 1417
8378 measured reflectionsk = 1010
2895 independent reflectionsl = 169
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.042Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.124H atoms treated by a mixture of independent and constrained refinement
S = 1.08 w = 1/[σ2(Fo2) + (0.066P)2 + 0.1896P]
where P = (Fo2 + 2Fc2)/3
2895 reflections(Δ/σ)max < 0.001
158 parametersΔρmax = 0.52 e Å3
0 restraintsΔρmin = 0.22 e Å3
0 constraints
Crystal data top
C13H17NO3V = 1204.6 (5) Å3
Mr = 235.28Z = 4
Monoclinic, P21/cMo Kα radiation
a = 12.980 (3) ŵ = 0.09 mm1
b = 7.6143 (17) ÅT = 173 K
c = 12.189 (3) Å0.32 × 0.26 × 0.18 mm
β = 90.497 (5)°
Data collection top
Bruker APEXII CCD
diffractometer
2271 reflections with I > 2σ(I)
8378 measured reflectionsRint = 0.027
2895 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0420 restraints
wR(F2) = 0.124H atoms treated by a mixture of independent and constrained refinement
S = 1.08Δρmax = 0.52 e Å3
2895 reflectionsΔρmin = 0.22 e Å3
158 parameters
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
C20.11028 (9)0.10275 (17)0.35921 (10)0.0283 (3)
C30.06871 (9)0.07971 (17)0.32619 (11)0.0304 (3)
H30.00600.06620.30720.037*
C40.12221 (11)0.15543 (17)0.22690 (12)0.0353 (3)
H4A0.08560.26210.20130.042*
H4B0.19390.18830.24630.042*
C50.12221 (11)0.01793 (18)0.13695 (11)0.0374 (3)
H5A0.15070.06880.06890.045*
H5B0.05080.02090.12140.045*
C60.18684 (10)0.13727 (17)0.17295 (10)0.0323 (3)
H6A0.26050.10380.17160.039*
H6B0.17660.23490.12040.039*
C70.20555 (10)0.36915 (17)0.31491 (12)0.0334 (3)
H7A0.16930.41530.38000.040*
H7B0.19510.45350.25400.040*
C80.31965 (10)0.35530 (15)0.34078 (11)0.0296 (3)
C90.35322 (10)0.27078 (17)0.43529 (11)0.0343 (3)
H90.30370.22270.48380.041*
C100.45748 (11)0.25429 (18)0.46121 (11)0.0349 (3)
H100.47860.19670.52680.042*
C110.53038 (10)0.32307 (16)0.39013 (11)0.0321 (3)
C120.49838 (10)0.4107 (2)0.29565 (12)0.0389 (3)
H120.54790.46000.24770.047*
C130.39415 (10)0.42600 (19)0.27143 (11)0.0365 (3)
H130.37300.48560.20660.044*
C140.66904 (13)0.2242 (2)0.50439 (15)0.0495 (4)
H14A0.64500.28940.56860.074*
H14B0.74450.21920.50550.074*
H14C0.64110.10470.50610.074*
N10.16062 (8)0.19805 (13)0.28388 (8)0.0270 (2)
O10.09468 (8)0.15790 (15)0.45317 (8)0.0444 (3)
O20.07623 (8)0.19755 (14)0.41449 (10)0.0457 (3)
H20.0256 (18)0.165 (3)0.4675 (17)0.069*
O30.63479 (7)0.31060 (14)0.40678 (9)0.0431 (3)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C20.0217 (5)0.0342 (6)0.0289 (6)0.0031 (5)0.0005 (4)0.0000 (5)
C30.0229 (6)0.0295 (6)0.0389 (7)0.0030 (5)0.0027 (5)0.0049 (5)
C40.0332 (7)0.0276 (6)0.0451 (8)0.0003 (5)0.0046 (6)0.0036 (5)
C50.0420 (8)0.0393 (7)0.0309 (7)0.0059 (6)0.0042 (5)0.0062 (5)
C60.0340 (7)0.0356 (7)0.0272 (6)0.0037 (5)0.0051 (5)0.0026 (5)
C70.0288 (6)0.0249 (6)0.0465 (8)0.0013 (5)0.0043 (5)0.0014 (5)
C80.0284 (6)0.0234 (6)0.0371 (7)0.0034 (5)0.0042 (5)0.0038 (5)
C90.0309 (7)0.0336 (7)0.0385 (7)0.0038 (5)0.0097 (5)0.0021 (5)
C100.0352 (7)0.0348 (7)0.0349 (7)0.0028 (5)0.0019 (5)0.0031 (5)
C110.0268 (6)0.0293 (6)0.0404 (7)0.0052 (5)0.0016 (5)0.0049 (5)
C120.0318 (7)0.0448 (8)0.0402 (7)0.0106 (6)0.0075 (5)0.0056 (6)
C130.0343 (7)0.0377 (7)0.0377 (7)0.0067 (6)0.0023 (5)0.0067 (6)
C140.0375 (8)0.0456 (9)0.0652 (11)0.0059 (7)0.0124 (7)0.0064 (7)
N10.0249 (5)0.0262 (5)0.0300 (5)0.0014 (4)0.0030 (4)0.0001 (4)
O10.0430 (6)0.0598 (7)0.0307 (5)0.0174 (5)0.0094 (4)0.0094 (5)
O20.0365 (6)0.0453 (6)0.0553 (7)0.0001 (4)0.0051 (5)0.0202 (5)
O30.0268 (5)0.0473 (6)0.0553 (7)0.0067 (4)0.0021 (4)0.0046 (5)
Geometric parameters (Å, º) top
C2—O11.2381 (15)C7—H7B0.9900
C2—N11.3443 (16)C8—C91.3865 (19)
C2—C31.5426 (18)C8—C131.3977 (18)
C3—O21.4039 (16)C9—C101.393 (2)
C3—C41.5145 (19)C9—H90.9500
C3—H31.0000C10—C111.3909 (19)
C4—C51.5160 (19)C10—H100.9500
C4—H4A0.9900C11—O31.3719 (16)
C4—H4B0.9900C11—C121.391 (2)
C5—C61.5121 (19)C12—C131.3871 (19)
C5—H5A0.9900C12—H120.9500
C5—H5B0.9900C13—H130.9500
C6—N11.4717 (16)C14—O31.4272 (19)
C6—H6A0.9900C14—H14A0.9800
C6—H6B0.9900C14—H14B0.9800
C7—N11.4753 (16)C14—H14C0.9800
C7—C81.5154 (18)O2—H20.96 (2)
C7—H7A0.9900
O1—C2—N1122.21 (12)C8—C7—H7B109.2
O1—C2—C3119.16 (11)H7A—C7—H7B107.9
N1—C2—C3118.62 (11)C9—C8—C13117.85 (12)
O2—C3—C4109.87 (11)C9—C8—C7120.32 (11)
O2—C3—C2110.71 (11)C13—C8—C7121.84 (12)
C4—C3—C2112.93 (10)C8—C9—C10121.88 (12)
O2—C3—H3107.7C8—C9—H9119.1
C4—C3—H3107.7C10—C9—H9119.1
C2—C3—H3107.7C11—C10—C9119.33 (13)
C3—C4—C5108.54 (11)C11—C10—H10120.3
C3—C4—H4A110.0C9—C10—H10120.3
C5—C4—H4A110.0O3—C11—C10123.94 (12)
C3—C4—H4B110.0O3—C11—C12116.31 (12)
C5—C4—H4B110.0C10—C11—C12119.75 (13)
H4A—C4—H4B108.4C13—C12—C11120.02 (12)
C6—C5—C4109.47 (10)C13—C12—H12120.0
C6—C5—H5A109.8C11—C12—H12120.0
C4—C5—H5A109.8C12—C13—C8121.16 (13)
C6—C5—H5B109.8C12—C13—H13119.4
C4—C5—H5B109.8C8—C13—H13119.4
H5A—C5—H5B108.2O3—C14—H14A109.5
N1—C6—C5112.35 (11)O3—C14—H14B109.5
N1—C6—H6A109.1H14A—C14—H14B109.5
C5—C6—H6A109.1O3—C14—H14C109.5
N1—C6—H6B109.1H14A—C14—H14C109.5
C5—C6—H6B109.1H14B—C14—H14C109.5
H6A—C6—H6B107.9C2—N1—C6125.13 (11)
N1—C7—C8112.04 (10)C2—N1—C7119.67 (11)
N1—C7—H7A109.2C6—N1—C7114.78 (10)
C8—C7—H7A109.2C3—O2—H2107.9 (12)
N1—C7—H7B109.2C11—O3—C14117.08 (12)
O1—C2—C3—O236.84 (16)O3—C11—C12—C13178.67 (13)
N1—C2—C3—O2144.47 (12)C10—C11—C12—C131.3 (2)
O1—C2—C3—C4160.52 (12)C11—C12—C13—C80.3 (2)
N1—C2—C3—C420.79 (15)C9—C8—C13—C120.7 (2)
O2—C3—C4—C5174.31 (10)C7—C8—C13—C12179.32 (12)
C2—C3—C4—C550.17 (14)O1—C2—N1—C6176.47 (12)
C3—C4—C5—C664.96 (14)C3—C2—N1—C64.89 (17)
C4—C5—C6—N148.71 (15)O1—C2—N1—C74.33 (18)
N1—C7—C8—C970.61 (15)C3—C2—N1—C7177.02 (10)
N1—C7—C8—C13109.37 (14)C5—C6—N1—C219.25 (17)
C13—C8—C9—C100.5 (2)C5—C6—N1—C7168.28 (10)
C7—C8—C9—C10179.46 (12)C8—C7—N1—C298.18 (13)
C8—C9—C10—C110.5 (2)C8—C7—N1—C674.74 (14)
C9—C10—C11—O3178.55 (12)C10—C11—O3—C141.19 (19)
C9—C10—C11—C121.5 (2)C12—C11—O3—C14178.80 (13)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O2—H2···O1i0.96 (2)1.84 (2)2.7708 (16)161.6 (19)
C6—H6B···O1ii0.992.433.3142 (17)148
C14—H14B···O2iii0.982.523.449 (2)158
Symmetry codes: (i) x, y, z+1; (ii) x, y+1/2, z1/2; (iii) x+1, y, z+1.

Experimental details

Crystal data
Chemical formulaC13H17NO3
Mr235.28
Crystal system, space groupMonoclinic, P21/c
Temperature (K)173
a, b, c (Å)12.980 (3), 7.6143 (17), 12.189 (3)
β (°) 90.497 (5)
V3)1204.6 (5)
Z4
Radiation typeMo Kα
µ (mm1)0.09
Crystal size (mm)0.32 × 0.26 × 0.18
Data collection
DiffractometerBruker APEXII CCD
Absorption correction
No. of measured, independent and
observed [I > 2σ(I)] reflections
8378, 2895, 2271
Rint0.027
(sin θ/λ)max1)0.661
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.042, 0.124, 1.08
No. of reflections2895
No. of parameters158
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.52, 0.22

Computer programs: APEX2 (Bruker, 2005), SAINT-NT (Bruker, 2005), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 2012) and SCHAKAL99 (Keller, 1999), WinGX (Farrugia, 2012) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O2—H2···O1i0.96 (2)1.84 (2)2.7708 (16)161.6 (19)
C6—H6B···O1ii0.992.433.3142 (17)148
C14—H14B···O2iii0.982.523.449 (2)158
Symmetry codes: (i) x, y, z+1; (ii) x, y+1/2, z1/2; (iii) x+1, y, z+1.
 

Acknowledgements

This work was supported by the University of the Witwaters­rand and the National Research Foundation, Pretoria (grant No. 78837).

References

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