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

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tert-Butyl 1-hy­dr­oxy­piperidine-2-carboxyl­ate

aFachbereich Chemie, Organische Chemie, Technische Universität Kaiserslautern, Erwin-Schrödinger-Strasse, D-67663 Kaiserslautern, Germany, and bFachbereich Chemie, Anorganische Chemie, Technische Universität Kaiserslautern, Erwin-Schrödinger-Strasse, D-67663 Kaiserslautern, Germany
*Correspondence e-mail: hartung@chemie.uni-kl.de

(Received 17 June 2011; accepted 5 July 2011; online 16 July 2011)

The title compound, C10H19NO3, is a disubstituted piperidine bearing substituents in two equatorial positions. One of the substituents is a hy­droxy group bound to nitro­gen and the second a tert-butyl ester group bound to the carbon next to the endocyclic nitro­gen. Enanti­omers of the title compound form hydrogen-bridged dimers across a center of inversion.

Related literature

For bond lengths, see: Allen et al. (1987[Allen, F. H., Kennard, O. & Watson, D. G. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1-19.]). For structural features associated with hydroxyl­amine, see: Chung-Phillips & Jebber (1995[Chung-Phillips, A. & Jebber, K. A. (1995). J. Chem. Phys. 102, 7080-7087.]). For details of vanadium(V)- and molybdenum(VI)-catalysed oxidations, see: Hartung & Greb (2002[Hartung, J. & Greb, M. (2002). J. Organomet. Chem. 661, 67-84.]); Reinhardt (2006[Reinhardt, G. (2006). J. Mol. Catal. A, 251, 177-184.]). For a related structure, see: Kliegel et al. (2002[Kliegel, W., Riebe, U., Patrick, B. O., Rettig, S. J. & Trotter, J. (2002). Acta Cryst. E58, o509-o510.]). For the synthesis of 1-hy­droxy piperidine-2-carboxyl­ic acid, see: Murahashi & Shiota (1987[Murahashi, S. & Shiota, T. (1987). Tetrahedron Lett. 28, 6469-6472.]).

[Scheme 1]

Experimental

Crystal data
  • C10H19NO3

  • Mr = 201.26

  • Monoclinic, P 21 /n

  • a = 10.1685 (3) Å

  • b = 12.1271 (2) Å

  • c = 10.2083 (3) Å

  • β = 110.377 (3)°

  • V = 1180.06 (5) Å3

  • Z = 4

  • Cu Kα radiation

  • μ = 0.68 mm−1

  • T = 150 K

  • 0.24 × 0.21 × 0.19 mm

Data collection
  • Oxford Diffraction Gemini S Ultra diffractometer

  • Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2008[Oxford Diffraction (2008). CrysAlis RED and CrysAlis CCD. Oxford Diffraction Ltd, Abingdon, England.]) Tmin = 0.854, Tmax = 0.882

  • 5815 measured reflections

  • 1851 independent reflections

  • 1440 reflections with I > 2σ(I)

  • Rint = 0.026

Refinement
  • R[F2 > 2σ(F2)] = 0.049

  • wR(F2) = 0.146

  • S = 1.09

  • 1851 reflections

  • 131 parameters

  • H-atom parameters constrained

  • Δρmax = 0.39 e Å−3

  • Δρmin = −0.23 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O3—H3⋯N1i 0.84 2.12 2.8136 (19) 139
Symmetry code: (i) -x, -y+2, -z.

Data collection: CrysAlis CCD (Oxford Diffraction, 2008[Oxford Diffraction (2008). CrysAlis RED and CrysAlis CCD. Oxford Diffraction Ltd, Abingdon, England.]); cell refinement: CrysAlis RED (Oxford Diffraction, 2008[Oxford Diffraction (2008). CrysAlis RED and CrysAlis CCD. Oxford Diffraction Ltd, Abingdon, England.]); data reduction: CrysAlis RED; 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 (Farrugia, 1997)[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]; software used to prepare material for publication: SHELXL97.

Supporting information


Comment top

1-Hydroxypiperidine-2-carboxylate (Murahashi & Shiota, 1987) attracted our attention, because the compound was expected to bind as dianion to early transition metal ions, such as vanadium(V) or molybdenum(VI). Complexes formed from vanadium(V) or molybdenum(VI) ions are formaly d0-metal centers. Complexes having such an electron configuration are able to activate peroxides at low temperatures, which is of importance for modern sustainable oxidation catalysis, for example in natural product synthesis (Hartung & Greb, 2002) or bleaching (Reinhardt, 2006). Since impurities from the synthesis of 1-hydroxypiperidine-2-carboxylate were difficult to separate from standard liquid/liquid and liquid/solid partitioning processes, we chose to convert this acid into a derived O-tert-butyl ester for subsequent sublimination. Colorless crystals of the title compound that deposited from the sublimation process were investigated via X-ray diffraction, in order to obtain a deeper structural insight into the product class of N-hydroxy α-aminocarboxylic acid esters.

The central structural element of the title compound, is a disubstituted piperidine ring. The N-heterocycle bears a hydroxy substituent at nitrogen and a tert-butyl O-ester substituent at the carbon next to the endocyclic nitrogen. Both substituents are bond to equatorial sites in piperidine (Figure 1). A distorted gauche arrangement of subunits C6–N1–O3–H3 = -90.30 ° and C2–N1–O3–H3 151.18 °, in combination with a N1–O3 distance of 1.4477 (18) Å, reflect typical structural characteristics of with compounds having a nitrogen oxygen single bond, such as hydroxylamine (Chung-Phillips & Jebber, 1995) or N-hydroxypiperidinium chloride (Kliegel et al., 2002). The geometrical parameters for the tert-butyl O-ester group in terms of bond distances and angles agree with reference data reported previously (Allen et al., 1987).

In the crystal, association of the title compound, occurs predominantly via H-bonding. Enantiomers of the title compound thus form H-bridged dimers (Figure 2 and Table 1) across a center of inversion [N1i···H3–O3 = 2.12 Å, N1i···O3 = 2.8136 (19)].

Related literature top

For reference on bond lengths, see: Allen et al. (1987). For structural features associated with hydroxylamine, see: Chung-Phillips & Jebber (1995). For details of vanadium(V)- and molybdenum(VI)-catalysed oxidations, see: Hartung & Greb (2002);Reinhardt (2006) . For a related structure, see: Kliegel et al. (2002). For the synthesis of 1-hydroxy piperidine-2-carboxylate, see: Murahashi & Shiota (1987). .

Experimental top

To a suspension of crude N-hydroxypiperidine-2-carboxylic acid (1.15 g, 8 mmol) (Murahashi & Shiota, 1987) in tert-butyl acetate (20 ml) was added at 298 K HClO4 [0.2 ml, 70% (w/w)]. The mixture was stirred for 10 min at 298 K and treated with a second batch of HClO4 [2 ml, 70% (w/w)]. Stirring was continued for 20 h at 298 K. pH of the reaction mixture was adjusted to 8–9 by addition of satd. aq. NaHCO3 [150 ml, 10% (w/w)] and NaOH pellets (0.8 g, 20 mmol). The resulting mixture was extracted with EtOAc (4 x 40 ml). Combined organic washings were dried (MgSO4) and concentrated under reduced pressure to furnish a brown oily residue that was purified by chromatography [SiO2, pentane/EtOAc = 2:1 (v/v)]. Yield: 412 mg (25%); mp 356 K; 1H NMR (600 MHz, CDCl3, δH p.p.m.): 1.20–1.30 (m, 1H), 1.47 (s, 9H), 1.52–1.78 (m, 4H), 1.97 (d, J = 11.1 Hz, 1H), 2.52 (t, J = 9.1 Hz, 1H), 3.02 (d, J = 10.6 Hz, 1H), 3.37 (d, J = 10.2 Hz, 1H), 6.56 (br s, 1H, OH). 13C NMR (151 MHz, CDCl3, δC p.p.m.): 23.1, 25.1, 28.0, 29.3, 57.4, 71.2, 81.2, 171.9. Anal. calcd. for C15H23NO2: C, 59.68; H, 9.52; N, 6.96%; Found C, 59.96; H, 9.49; N 6.94%. Crystalls suitable for X-ray diffraction were obtained by slow sublimation of (I) at 340 K and 0.1 mbar.

Refinement top

All H atoms were positioned geometrically and treated as riding atoms, with C—H distances in the range 0.98–1.00Å and with Uiso(H) set at 1.2Ueq (CH2, CH) or 1.5Ueq (CH3 and OH) of the parent atom. A free rotating group refinement was used for CH3 and OH H atoms.

Computing details top

Data collection: CrysAlis CCD (Oxford Diffraction, 2008); cell refinement: CrysAlis RED (Oxford Diffraction, 2008); data reduction: CrysAlis RED (Oxford Diffraction, 2008); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. Molecular structure of title compound in the solid state. Displacement ellipsoids are drawn at the 50% probability level.
[Figure 2] Fig. 2. H-bridged dimers of title compound in the solid state [hydrogen bonds shown as dashed lines symmetry code: (i) -x, -y + 2, -z].
tert-Butyl 1-hydroxypiperidine-2-carboxylate top
Crystal data top
C10H19NO3F(000) = 440
Mr = 201.26Dx = 1.133 Mg m3
Monoclinic, P21/nMelting point: 356 K
Hall symbol: -P 2ynCu Kα radiation, λ = 1.54184 Å
a = 10.1685 (3) ÅCell parameters from 2751 reflections
b = 12.1271 (2) Åθ = 3.6–62.6°
c = 10.2083 (3) ŵ = 0.68 mm1
β = 110.377 (3)°T = 150 K
V = 1180.06 (5) Å3Indifferent fragment, colourless
Z = 40.24 × 0.21 × 0.19 mm
Data collection top
Oxford Diffraction Gemini S Ultra
diffractometer
1851 independent reflections
Radiation source: fine-focus sealed tube1440 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.026
Detector resolution: 16.1399 pixels mm-1θmax = 62.7°, θmin = 6.4°
ω–scansh = 1111
Absorption correction: multi-scan
(CrysAlis RED; Oxford Diffraction, 2008)
k = 1312
Tmin = 0.854, Tmax = 0.882l = 1111
5815 measured reflections
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)] = 0.049Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.146H-atom parameters constrained
S = 1.09 w = 1/[σ2(Fo2) + (0.1003P)2]
where P = (Fo2 + 2Fc2)/3
1851 reflections(Δ/σ)max = 0.001
131 parametersΔρmax = 0.39 e Å3
0 restraintsΔρmin = 0.23 e Å3
Crystal data top
C10H19NO3V = 1180.06 (5) Å3
Mr = 201.26Z = 4
Monoclinic, P21/nCu Kα radiation
a = 10.1685 (3) ŵ = 0.68 mm1
b = 12.1271 (2) ÅT = 150 K
c = 10.2083 (3) Å0.24 × 0.21 × 0.19 mm
β = 110.377 (3)°
Data collection top
Oxford Diffraction Gemini S Ultra
diffractometer
1851 independent reflections
Absorption correction: multi-scan
(CrysAlis RED; Oxford Diffraction, 2008)
1440 reflections with I > 2σ(I)
Tmin = 0.854, Tmax = 0.882Rint = 0.026
5815 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0490 restraints
wR(F2) = 0.146H-atom parameters constrained
S = 1.09Δρmax = 0.39 e Å3
1851 reflectionsΔρmin = 0.23 e Å3
131 parameters
Special details top

Experimental. CrysAlis RED, Oxford Diffraction Ltd., (Version 1.171.31.8) Empirical absorption correction using spherical harmonics,implemented in SCALE3 ABSPACK scaling algorithm.

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) top
xyzUiso*/Ueq
C10.22238 (18)0.85238 (14)0.04530 (19)0.0323 (4)
O10.11112 (15)0.80571 (12)0.08516 (16)0.0512 (5)
O20.32151 (13)0.84628 (10)0.10296 (13)0.0368 (4)
C20.27379 (18)0.92188 (14)0.08639 (18)0.0330 (4)
H20.35320.96990.08500.040*
N10.15807 (15)0.98997 (12)0.09477 (14)0.0313 (4)
O30.12723 (13)1.06522 (10)0.02218 (14)0.0401 (4)
H30.04251.08390.04810.060*
C30.3223 (2)0.84527 (16)0.2126 (2)0.0439 (5)
H3A0.24490.79460.20930.053*
H3B0.40190.80020.20850.053*
C40.3675 (2)0.9091 (2)0.3492 (2)0.0541 (6)
H4A0.45260.95280.35900.065*
H4B0.39010.85720.42890.065*
C50.2493 (2)0.9855 (2)0.3503 (2)0.0529 (6)
H5A0.16860.94110.35320.063*
H5B0.28141.03230.43510.063*
C60.2036 (2)1.05791 (16)0.2217 (2)0.0427 (5)
H6A0.12541.10600.22300.051*
H6B0.28261.10560.22170.051*
C70.3043 (2)0.77301 (16)0.22421 (19)0.0386 (5)
C80.1799 (2)0.8114 (2)0.3490 (2)0.0554 (6)
H8A0.19100.88970.36640.083*
H8B0.09310.80080.32920.083*
H8C0.17550.76830.43170.083*
C90.2929 (3)0.65452 (17)0.1852 (2)0.0519 (6)
H9A0.20540.64400.16680.078*
H9B0.37280.63600.10120.078*
H9C0.29320.60650.26230.078*
C100.4397 (2)0.79292 (19)0.2509 (2)0.0509 (6)
H10A0.51930.77040.16880.076*
H10B0.44810.87150.26910.076*
H10C0.43950.74980.33220.076*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0292 (9)0.0312 (9)0.0348 (10)0.0023 (7)0.0091 (8)0.0018 (8)
O10.0362 (8)0.0574 (9)0.0610 (10)0.0095 (7)0.0185 (7)0.0249 (7)
O20.0354 (7)0.0415 (7)0.0341 (7)0.0039 (5)0.0131 (6)0.0072 (5)
C20.0282 (9)0.0354 (9)0.0346 (10)0.0003 (7)0.0099 (7)0.0031 (8)
N10.0323 (8)0.0312 (8)0.0297 (8)0.0030 (6)0.0100 (6)0.0012 (6)
O30.0359 (7)0.0372 (7)0.0476 (8)0.0030 (5)0.0151 (6)0.0163 (6)
C30.0411 (11)0.0414 (10)0.0452 (12)0.0090 (8)0.0097 (9)0.0070 (9)
C40.0517 (12)0.0692 (13)0.0336 (11)0.0100 (11)0.0052 (9)0.0044 (10)
C50.0500 (12)0.0755 (14)0.0312 (11)0.0035 (11)0.0117 (9)0.0094 (10)
C60.0361 (10)0.0424 (11)0.0490 (12)0.0018 (8)0.0144 (9)0.0150 (9)
C70.0433 (11)0.0444 (10)0.0280 (9)0.0017 (8)0.0120 (8)0.0086 (8)
C80.0564 (14)0.0666 (14)0.0355 (11)0.0055 (11)0.0063 (10)0.0027 (10)
C90.0704 (15)0.0476 (12)0.0461 (12)0.0023 (10)0.0307 (11)0.0073 (10)
C100.0546 (13)0.0609 (13)0.0411 (11)0.0055 (10)0.0217 (10)0.0095 (10)
Geometric parameters (Å, º) top
C1—O11.202 (2)C5—H5A0.9900
C1—O21.335 (2)C5—H5B0.9900
C1—C21.517 (2)C6—H6A0.9900
O2—C71.484 (2)C6—H6B0.9900
C2—N11.464 (2)C7—C91.506 (3)
C2—C31.524 (3)C7—C101.514 (3)
C2—H21.0000C7—C81.522 (3)
N1—O31.4477 (18)C8—H8A0.9800
N1—C61.468 (2)C8—H8B0.9800
O3—H30.8400C8—H8C0.9800
C3—C41.520 (3)C9—H9A0.9800
C3—H3A0.9900C9—H9B0.9800
C3—H3B0.9900C9—H9C0.9800
C4—C51.521 (3)C10—H10A0.9800
C4—H4A0.9900C10—H10B0.9800
C4—H4B0.9900C10—H10C0.9800
C5—C61.512 (3)
O1—C1—O2126.22 (16)H5A—C5—H5B108.1
O1—C1—C2123.69 (16)N1—C6—C5110.36 (16)
O2—C1—C2109.97 (14)N1—C6—H6A109.6
C1—O2—C7120.89 (13)C5—C6—H6A109.6
N1—C2—C1109.21 (13)N1—C6—H6B109.6
N1—C2—C3108.94 (15)C5—C6—H6B109.6
C1—C2—C3108.69 (15)H6A—C6—H6B108.1
N1—C2—H2110.0O2—C7—C9110.40 (15)
C1—C2—H2110.0O2—C7—C10101.79 (14)
C3—C2—H2110.0C9—C7—C10110.98 (17)
O3—N1—C2104.77 (12)O2—C7—C8109.72 (16)
O3—N1—C6106.58 (13)C9—C7—C8113.25 (18)
C2—N1—C6110.82 (13)C10—C7—C8110.10 (17)
N1—O3—H3109.5C7—C8—H8A109.5
C4—C3—C2111.74 (16)C7—C8—H8B109.5
C4—C3—H3A109.3H8A—C8—H8B109.5
C2—C3—H3A109.3C7—C8—H8C109.5
C4—C3—H3B109.3H8A—C8—H8C109.5
C2—C3—H3B109.3H8B—C8—H8C109.5
H3A—C3—H3B107.9C7—C9—H9A109.5
C3—C4—C5109.27 (17)C7—C9—H9B109.5
C3—C4—H4A109.8H9A—C9—H9B109.5
C5—C4—H4A109.8C7—C9—H9C109.5
C3—C4—H4B109.8H9A—C9—H9C109.5
C5—C4—H4B109.8H9B—C9—H9C109.5
H4A—C4—H4B108.3C7—C10—H10A109.5
C6—C5—C4110.60 (17)C7—C10—H10B109.5
C6—C5—H5A109.5H10A—C10—H10B109.5
C4—C5—H5A109.5C7—C10—H10C109.5
C6—C5—H5B109.5H10A—C10—H10C109.5
C4—C5—H5B109.5H10B—C10—H10C109.5
O1—C1—O2—C73.0 (3)C1—C2—C3—C4176.65 (16)
C2—C1—O2—C7173.14 (14)C2—C3—C4—C554.3 (2)
O1—C1—C2—N142.6 (2)C3—C4—C5—C653.9 (3)
O2—C1—C2—N1141.07 (14)O3—N1—C6—C5175.52 (14)
O1—C1—C2—C376.1 (2)C2—N1—C6—C562.1 (2)
O2—C1—C2—C3100.19 (17)C4—C5—C6—N158.1 (2)
C1—C2—N1—O365.86 (16)C1—O2—C7—C961.7 (2)
C3—C2—N1—O3175.55 (13)C1—O2—C7—C10179.57 (16)
C1—C2—N1—C6179.56 (14)C1—O2—C7—C863.8 (2)
C3—C2—N1—C660.98 (19)C2—N1—O3—H3152.19
N1—C2—C3—C457.7 (2)C6—N1—O3—H390.30
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O3—H3···N1i0.842.122.8136 (19)139
Symmetry code: (i) x, y+2, z.

Experimental details

Crystal data
Chemical formulaC10H19NO3
Mr201.26
Crystal system, space groupMonoclinic, P21/n
Temperature (K)150
a, b, c (Å)10.1685 (3), 12.1271 (2), 10.2083 (3)
β (°) 110.377 (3)
V3)1180.06 (5)
Z4
Radiation typeCu Kα
µ (mm1)0.68
Crystal size (mm)0.24 × 0.21 × 0.19
Data collection
DiffractometerOxford Diffraction Gemini S Ultra
diffractometer
Absorption correctionMulti-scan
(CrysAlis RED; Oxford Diffraction, 2008)
Tmin, Tmax0.854, 0.882
No. of measured, independent and
observed [I > 2σ(I)] reflections
5815, 1851, 1440
Rint0.026
(sin θ/λ)max1)0.576
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.049, 0.146, 1.09
No. of reflections1851
No. of parameters131
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.39, 0.23

Computer programs: CrysAlis CCD (Oxford Diffraction, 2008), CrysAlis RED (Oxford Diffraction, 2008), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O3—H3···N1i0.842.122.8136 (19)139
Symmetry code: (i) x, y+2, z.
 

Acknowledgements

This work was supported by the Deutsche Bundesstiftung Umwelt (grant No. 20007/885; scholarship for OB).

References

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