1,10,10-Trimethyl-5-phenyl-3-oxa-4-aza­tri­cyclo­[5.2.1.02,6]dec-4-en-2-ol

Boualy, B.; Harrad, M.A.; Oudahmane, A.; Benharref, A.; Berraho, M.

doi:10.1107/S160053681302000X

organic compounds

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ISSN: 2056-9890

Volume 69| Part 8| August 2013| Page o1314

doi:10.1107/S160053681302000X

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1,10,10-Trimethyl-5-phenyl-3-oxa-4-azatricyclo[5.2.1.0^2,6]dec-4-en-2-ol

Brahim Boualy,^a ^* Mohamed Anouar Harrad,^a Abdelghani Oudahmane,^b Ahmed Benharref ^c and Moha Berraho ^c

^aLaboratoire de Chimie de Coordination, Faculté des Sciences-Semlalia, BP 2390, 40001 Marrakech, Morocco, ^bLaboratoire des Matériaux Inorganiques, UMR CNRS 6002, Université Blaise Pascal, 24 Avenue des Landais, 63177 Aubière, France, and ^cLaboratoire de Chimie des Substances Naturelles, Unité Associé au CNRST (URAC16), Faculté des Sciences-Semlalia, BP 2390, Boulevard My Abdellah, 40000 Marrakech, Morocco
^*Correspondence e-mail: berraho@uca.ma

(Received 10 July 2013; accepted 19 July 2013; online 24 July 2013)

The title compound, C₁₇H₂₁NO₂, was synthesized by the reaction of (1R)-(+)-3-benzylcamphor and hydroxylamine. The oxazole ring makes a dihedral angle of 23.42 (16)° with the phenyl ring. The six-membered ring of the norboryl group adopts a boat conformation, whereas each of the five-membered rings of the norboryl group displays a flattened envelope conformation, with the C atom carrying the methyl groups representing the flap for both rings. In the crystal, molecules are linked into zigzag chains propagating along the b axis by O—H⋯N hydrogen bonds.

Related literature

For the functionalization of camphor, see: Jennings & Herschbach (1965 ); Pastrán et al., (2011 ). For transition metal complexes of camphor, see: Spannenberg et al. (2002 ); Harrad et al. (2010 ); Ait Ali et al. (2006 ); Gaudo et al. (2011 ). For ring-puckering parameters, see: Cremer & Pople (1975 ).

Experimental

Crystal data

C₁₇H₂₁NO₂
M_r = 271.35
Monoclinic, C 2
a = 22.1681 (18) Å
b = 6.6134 (5) Å
c = 10.7358 (8) Å
β = 108.277 (3)°
V = 1494.5 (2) Å³
Z = 4
Mo Kα radiation
μ = 0.08 mm⁻¹
T = 296 K
0.58 × 0.34 × 0.14 mm

Data collection

Bruker APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 2008 ) T_min = 0.627, T_max = 0.745
4379 measured reflections
1350 independent reflections
1220 reflections with I > 2σ(I)
R_int = 0.025

Refinement

R[F² > 2σ(F²)] = 0.042
wR(F²) = 0.106
S = 1.08
1350 reflections
186 parameters
1 restraint
H-atom parameters constrained
Δρ_max = 0.29 e Å⁻³
Δρ_min = −0.24 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O2—H2⋯N2ⁱ	0.82	2.06	2.877 (3)	174
Symmetry code: (i) $[-x+{\script{3\over 2}}, y+{\script{1\over 2}}, -z]$ .

Data collection: APEX2 (Bruker, 2009 ); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT; 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 PLATON (Spek, 2009 ); software used to prepare material for publication: WinGX (Farrugia, 2012).

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S160053681302000X/bt6921sup1.cif

checkCIF report

Comment top

The versatility and importance of camphor as a chiral starting material in the synthesis of natural products is primarily due to the availability of methods for the introduction of functional groups (Jennings & Herschbach, 1965; Pastrán et al., 2011). We have developed a series of complexes based on camphor 1,3-diketonato ligands (Spannenberg et al., 2002; Harrad et al., 2010; Ait Ali et al., 2006), and their application in catalytic asymmetric reactions has been described (Gaudo et al., 2011). In this work, we present the structure of a new heterocyclic compound (1,10,10-trimethyl-5-phenyl-3-oxa-4-aza-tricyclo[5.2.1.02,6]dec-4- en-2-ol)) which we have synthesized by hetercyclization from benzylcamphor with hydroxylamine. In the molecule (Fig. 1), the six-membered ring of the norboryl system adopts a boat conformation, as indicated by Cremer & Pople (1975) puckering parameters Q = 0.966 (3) Å and spherical polar angle θ = 89.71 (17)° with ϕ = 121.07 (19)°. The two fused five-membered rings display an envelope conformation with Q = 0.602 (3) Å and ϕ = 287.7 (3)° for the first ring (C6, C7, C9, C10, C12) and Q = 0.590 (4) Å and ϕ = 37.7 (4)° for the other ring (C7, C10, C12, C14, C19). In the crystal structure, molecules are linked into zigzag chains (Fig. 2) running along the b axis by intermolecular O—H···N hydrogen bonds (Table 1).

Related literature top

For the functionalization of camphor, see: Jennings & Herschbach (1965); Pastrán et al., (2011). For transition metal complexes of camphor, see: Spannenberg et al. (2002); Harrad et al. (2010); Ait Ali et al. (2006); Gaudo et al. (2011). For ring-puckering parameters, see: Cremer & Pople (1975).

Experimental top

(1R)-(+)-3-benzyl-camphor (1 mmol), and hydroxylamine (2 mmol), in dichloromethane (10 ml) were vigorously stirred at reflux. The progress of the reaction was followed by TLC. The reaction went to completion after 24 h. After completion of the reaction, the mixture was diluted with H₂O (10 ml) and extracted with EtOAc (2 × 10 ml) and dried over Na₂SO₄. The title compound was isolated as a white powder by column chromatography on silica gel using ethyl acetate–n-hexane as eluant (yield 79%; m.p. = 145°C). Colourless single crystals suitable for X-ray analysis were obtained by slow evaporation of n-hexane solution.

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); 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 PLATON (Spek, 2009); software used to prepare material for publication: WinGX (Farrugia, 2012).

Figures top

	Fig. 1. Molecular structure of the title compound with the atom-labelling scheme. Displacement ellipsoids are drawn at the 30% probability. level. H atoms are represented as small spheres of arbitrary radii.
	Fig. 2. Partial packing view showing the O—H···N and N—H···N interactions (dashed lines) and the formation of a chain parallel to the b axis. H atoms not involved in hydrogen bonding have been omitted for clarity.

1,10,10-Trimethyl-5-phenyl-3-oxa-4-azatricyclo[5.2.1.0^2,6]dec-4-en-2-ol top

Crystal data top

C₁₇H₂₁NO₂	F(000) = 584
M_r = 271.35	D_x = 1.202 Mg m⁻³
Monoclinic, C2	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: C 2y	Cell parameters from 2921 reflections
a = 22.1681 (18) Å	θ = 3.2–24.5°
b = 6.6134 (5) Å	µ = 0.08 mm⁻¹
c = 10.7358 (8) Å	T = 296 K
β = 108.277 (3)°	Plaquet, colourless
V = 1494.5 (2) Å³	0.58 × 0.34 × 0.14 mm
Z = 4

Data collection top

Bruker APEXII CCD diffractometer	1350 independent reflections
Radiation source: fine-focus sealed tube	1220 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.025
Detector resolution: 8.3333 pixels mm^-1	θ_max = 24.5°, θ_min = 3.2°
ω and ϕ scans	h = −25→25
Absorption correction: multi-scan (SADABS; Sheldrick, 2008)	k = −6→7
T_min = 0.627, T_max = 0.745	l = −12→12
4379 measured reflections

Refinement top

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)] = 0.042	H-atom parameters constrained
wR(F²) = 0.106	w = 1/[σ²(F_o²) + (0.0701P)² + 0.2932P] where P = (F_o² + 2F_c²)/3
S = 1.08	(Δ/σ)_max < 0.001
1350 reflections	Δρ_max = 0.29 e Å⁻³
186 parameters	Δρ_min = −0.24 e Å⁻³
1 restraint	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.050 (5)

Crystal data top

C₁₇H₂₁NO₂	V = 1494.5 (2) Å³
M_r = 271.35	Z = 4
Monoclinic, C2	Mo Kα radiation
a = 22.1681 (18) Å	µ = 0.08 mm⁻¹
b = 6.6134 (5) Å	T = 296 K
c = 10.7358 (8) Å	0.58 × 0.34 × 0.14 mm
β = 108.277 (3)°

Data collection top

Bruker APEXII CCD diffractometer	1350 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 2008)	1220 reflections with I > 2σ(I)
T_min = 0.627, T_max = 0.745	R_int = 0.025
4379 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.042	1 restraint
wR(F²) = 0.106	H-atom parameters constrained
S = 1.08	Δρ_max = 0.29 e Å⁻³
1350 reflections	Δρ_min = −0.24 e Å⁻³
186 parameters

Special details top

Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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 > 2σ(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

	x	y	z	U_iso*/U_eq
C5	0.81485 (10)	0.9730 (4)	−0.0870 (2)	0.0383 (6)
C6	0.85865 (11)	1.0215 (4)	0.0464 (2)	0.0393 (6)
H6	0.8609	1.1673	0.0637	0.047*
C7	0.92540 (11)	0.9251 (5)	0.0815 (2)	0.0527 (8)
H7	0.9569	1.0084	0.0585	0.063*
C8	0.91859 (14)	0.7103 (6)	0.0251 (3)	0.0632 (9)
H8A	0.8924	0.7088	−0.0662	0.076*
H8B	0.9597	0.6520	0.0325	0.076*
C9	0.88635 (13)	0.5975 (5)	0.1116 (3)	0.0560 (7)
H9A	0.9122	0.4844	0.1557	0.067*
H9B	0.8450	0.5473	0.0598	0.067*
C1	0.87986 (11)	0.7567 (4)	0.2119 (2)	0.0445 (7)
C2	0.82786 (10)	0.9070 (4)	0.1358 (2)	0.0387 (6)
C10	0.94087 (11)	0.8860 (5)	0.2308 (2)	0.0520 (7)
C12	1.00340 (13)	0.7670 (7)	0.2908 (3)	0.0777 (11)
H12A	1.0381	0.8412	0.2775	0.116*
H12B	1.0001	0.6374	0.2490	0.116*
H12C	1.0107	0.7487	0.3831	0.116*
C11	0.94630 (15)	1.0792 (6)	0.3124 (3)	0.0690 (9)
H11A	0.9852	1.1475	0.3175	0.104*
H11B	0.9461	1.0448	0.3991	0.104*
H11C	0.9110	1.1664	0.2716	0.104*
C13	0.82295 (11)	1.0459 (5)	−0.2104 (2)	0.0443 (6)
C18	0.79751 (13)	0.9407 (6)	−0.3273 (2)	0.0586 (8)
H18	0.7746	0.8225	−0.3287	0.070*
C17	0.80638 (16)	1.0122 (7)	−0.4421 (3)	0.0738 (12)
H17	0.7889	0.9415	−0.5201	0.089*
C16	0.83984 (16)	1.1823 (8)	−0.4422 (3)	0.0794 (12)
H16	0.8461	1.2269	−0.5193	0.095*
C15	0.86471 (18)	1.2897 (8)	−0.3279 (4)	0.0852 (12)
H15	0.8870	1.4086	−0.3283	0.102*
C14	0.85657 (16)	1.2210 (6)	−0.2119 (3)	0.0671 (9)
H14	0.8739	1.2935	−0.1347	0.080*
C19	0.86922 (15)	0.6664 (6)	0.3337 (3)	0.0625 (9)
H19A	0.8294	0.5958	0.3092	0.094*
H19B	0.8686	0.7726	0.3942	0.094*
H19C	0.9030	0.5738	0.3745	0.094*
O1	0.77279 (7)	0.8072 (3)	0.04364 (16)	0.0467 (5)
N2	0.77018 (9)	0.8524 (4)	−0.08639 (18)	0.0438 (6)
O2	0.80582 (8)	1.0188 (3)	0.22155 (14)	0.0519 (6)
H2	0.7864	1.1178	0.1833	0.078*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C5	0.0383 (11)	0.0409 (14)	0.0357 (11)	−0.0014 (11)	0.0116 (9)	−0.0065 (11)
C6	0.0455 (12)	0.0374 (14)	0.0336 (11)	−0.0048 (11)	0.0103 (9)	−0.0014 (11)
C7	0.0380 (12)	0.070 (2)	0.0502 (14)	−0.0076 (14)	0.0144 (10)	0.0066 (15)
C8	0.0559 (15)	0.075 (2)	0.0647 (17)	0.0157 (17)	0.0276 (13)	−0.0043 (17)
C9	0.0555 (14)	0.0465 (17)	0.0643 (17)	0.0097 (14)	0.0165 (12)	−0.0061 (15)
C1	0.0451 (12)	0.0443 (17)	0.0422 (13)	0.0041 (12)	0.0109 (10)	0.0047 (12)
C2	0.0386 (11)	0.0430 (16)	0.0341 (11)	0.0009 (11)	0.0107 (9)	−0.0011 (11)
C10	0.0428 (12)	0.059 (2)	0.0478 (13)	0.0021 (14)	0.0047 (10)	0.0047 (15)
C12	0.0453 (14)	0.098 (3)	0.077 (2)	0.0091 (18)	0.0011 (13)	0.015 (2)
C11	0.0690 (17)	0.068 (2)	0.0520 (16)	−0.0134 (19)	−0.0069 (12)	0.0013 (17)
C13	0.0453 (12)	0.0521 (17)	0.0358 (12)	0.0018 (13)	0.0130 (9)	−0.0030 (12)
C18	0.0577 (14)	0.078 (2)	0.0395 (13)	−0.0028 (16)	0.0148 (11)	−0.0094 (15)
C17	0.0720 (18)	0.116 (4)	0.0356 (14)	0.009 (2)	0.0197 (13)	−0.0077 (18)
C16	0.0704 (19)	0.126 (4)	0.0463 (17)	0.013 (2)	0.0247 (14)	0.024 (2)
C15	0.090 (2)	0.097 (3)	0.075 (2)	−0.017 (2)	0.0348 (18)	0.024 (2)
C14	0.0841 (19)	0.070 (2)	0.0478 (15)	−0.019 (2)	0.0218 (13)	0.0020 (16)
C19	0.0637 (16)	0.066 (2)	0.0557 (16)	0.0106 (17)	0.0162 (13)	0.0225 (17)
O1	0.0397 (8)	0.0571 (13)	0.0423 (9)	−0.0071 (9)	0.0115 (6)	0.0039 (8)
N2	0.0418 (10)	0.0513 (15)	0.0371 (10)	−0.0040 (11)	0.0107 (8)	−0.0025 (10)
O2	0.0621 (11)	0.0616 (14)	0.0337 (9)	0.0215 (10)	0.0174 (7)	0.0054 (9)

Geometric parameters (Å, º) top

C5—N2	1.273 (3)	C12—H12A	0.9600
C5—C13	1.473 (3)	C12—H12B	0.9600
C5—C6	1.492 (3)	C12—H12C	0.9600
C6—C2	1.540 (3)	C11—H11A	0.9600
C6—C7	1.545 (4)	C11—H11B	0.9600
C6—H6	0.9800	C11—H11C	0.9600
C7—C8	1.534 (5)	C13—C14	1.380 (5)
C7—C10	1.552 (4)	C13—C18	1.390 (4)
C7—H7	0.9800	C18—C17	1.391 (4)
C8—C9	1.532 (4)	C18—H18	0.9300
C8—H8A	0.9700	C17—C16	1.348 (6)
C8—H8B	0.9700	C17—H17	0.9300
C9—C1	1.545 (4)	C16—C15	1.374 (6)
C9—H9A	0.9700	C16—H16	0.9300
C9—H9B	0.9700	C15—C14	1.390 (4)
C1—C19	1.522 (4)	C15—H15	0.9300
C1—C2	1.547 (3)	C14—H14	0.9300
C1—C10	1.558 (4)	C19—H19A	0.9600
C2—O2	1.384 (3)	C19—H19B	0.9600
C2—O1	1.465 (3)	C19—H19C	0.9600
C10—C11	1.532 (5)	O1—N2	1.411 (3)
C10—C12	1.548 (4)	O2—H2	0.8200

N2—C5—C13	121.6 (2)	C11—C10—C1	116.2 (2)
N2—C5—C6	113.7 (2)	C12—C10—C1	113.8 (3)
C13—C5—C6	124.6 (2)	C7—C10—C1	93.18 (19)
C5—C6—C2	102.15 (19)	C10—C12—H12A	109.5
C5—C6—C7	115.5 (2)	C10—C12—H12B	109.5
C2—C6—C7	102.88 (19)	H12A—C12—H12B	109.5
C5—C6—H6	111.8	C10—C12—H12C	109.5
C2—C6—H6	111.8	H12A—C12—H12C	109.5
C7—C6—H6	111.8	H12B—C12—H12C	109.5
C8—C7—C6	108.5 (2)	C10—C11—H11A	109.5
C8—C7—C10	102.5 (3)	C10—C11—H11B	109.5
C6—C7—C10	101.8 (2)	H11A—C11—H11B	109.5
C8—C7—H7	114.2	C10—C11—H11C	109.5
C6—C7—H7	114.2	H11A—C11—H11C	109.5
C10—C7—H7	114.2	H11B—C11—H11C	109.5
C9—C8—C7	102.6 (2)	C14—C13—C18	118.5 (3)
C9—C8—H8A	111.2	C14—C13—C5	120.2 (2)
C7—C8—H8A	111.2	C18—C13—C5	121.3 (3)
C9—C8—H8B	111.2	C17—C18—C13	120.0 (3)
C7—C8—H8B	111.2	C17—C18—H18	120.0
H8A—C8—H8B	109.2	C13—C18—H18	120.0
C8—C9—C1	104.7 (3)	C16—C17—C18	121.0 (3)
C8—C9—H9A	110.8	C16—C17—H17	119.5
C1—C9—H9A	110.8	C18—C17—H17	119.5
C8—C9—H9B	110.8	C17—C16—C15	119.9 (3)
C1—C9—H9B	110.8	C17—C16—H16	120.1
H9A—C9—H9B	108.9	C15—C16—H16	120.1
C19—C1—C9	113.9 (3)	C16—C15—C14	120.2 (4)
C19—C1—C2	114.5 (2)	C16—C15—H15	119.9
C9—C1—C2	106.7 (2)	C14—C15—H15	119.9
C19—C1—C10	117.8 (2)	C13—C14—C15	120.4 (3)
C9—C1—C10	101.4 (2)	C13—C14—H14	119.8
C2—C1—C10	100.9 (2)	C15—C14—H14	119.8
O2—C2—O1	107.27 (17)	C1—C19—H19A	109.5
O2—C2—C6	118.0 (2)	C1—C19—H19B	109.5
O1—C2—C6	103.82 (17)	H19A—C19—H19B	109.5
O2—C2—C1	110.61 (19)	C1—C19—H19C	109.5
O1—C2—C1	113.1 (2)	H19A—C19—H19C	109.5
C6—C2—C1	104.03 (18)	H19B—C19—H19C	109.5
C11—C10—C12	106.6 (3)	N2—O1—C2	109.86 (17)
C11—C10—C7	113.8 (3)	C5—N2—O1	110.33 (18)
C12—C10—C7	113.2 (2)	C2—O2—H2	109.5

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O2—H2···N2ⁱ	0.82	2.06	2.877 (3)	174

Symmetry code: (i) −x+3/2, y+1/2, −z.

Experimental details

Crystal data
Chemical formula	C₁₇H₂₁NO₂
M_r	271.35
Crystal system, space group	Monoclinic, C2
Temperature (K)	296
a, b, c (Å)	22.1681 (18), 6.6134 (5), 10.7358 (8)
β (°)	108.277 (3)
V (Å³)	1494.5 (2)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.08
Crystal size (mm)	0.58 × 0.34 × 0.14

Data collection
Diffractometer	Bruker APEXII CCD diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 2008)
T_min, T_max	0.627, 0.745
No. of measured, independent and observed [I > 2σ(I)] reflections	4379, 1350, 1220
R_int	0.025
(sin θ/λ)_max (Å⁻¹)	0.584

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.042, 0.106, 1.08
No. of reflections	1350
No. of parameters	186
No. of restraints	1
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.29, −0.24

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

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O2—H2···N2ⁱ	0.82	2.06	2.877 (3)	174

Symmetry code: (i) −x+3/2, y+1/2, −z.

Acknowledgements

The authors thank Professor Daniel Avignant for the X-ray measurements.

References

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