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Journal logoCRYSTALLOGRAPHIC
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ISSN: 2056-9890

tert-Butyl 6-acetamido-3,4-di­hydro-2H-1,4-benzoxazine-4-carboxyl­ate

aKey Laboratory of Nuclear Medicine, Ministry of Health, Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi 214063, People's Republic of China
*Correspondence e-mail: gnal8002bxg@yahoo.com.cn

(Received 26 August 2010; accepted 15 September 2010; online 25 September 2010)

The title mol­ecule, C15H20N2O4, contains a benzene ring fused to an oxazine ring and one tert-but­oxy­carbonyl group bound to the N atom. An intra­molecular C—H⋯O inter­action occurs. In the crystal, mol­ecules are linked through inter­molecular N—H⋯O and C—H⋯O hydrogen bonds.

Related literature

For the pharmacological properties of phenyl­morpholine derivatives, see: Bourlot et al. (1998[Bourlot, A.-S., Sánchez, I., Dureng, G., Guillaumet, G., Massingham, R., Monteil, A., Winslow, E., Pujol, M. D. & Mérour, J.-Y. (1998). J. Med. Chem. 41, 3142-3158.]); Albanese et al. (2003[Albanese, D., Landini, D., Lupi, V. & Penso, M. (2003). Ind. Eng. Chem. Res. 42, 680-686.]); La et al. (2008[La, D. S., Belzile, J., Bready, J. V., Coxon, A., DeMelfi, T., Doerr, N., Estrada, J., Flynn, J. C., Flynn, S. R., Graceffa, R. F., Harriman, S. P., Larrow, J. F., Long, A. M., Martin, M. W., Morrison, M. J., Patel, V. F., Roveto, P. M., Wang, L., Weiss, M. N., Whittington, D. A., Teffera, Y., Zhao, Z., Polverino, A. J. & Harmange, J.-C. (2008). J. Med. Chem. 51, 1695-1705.]). For structures, see: Chen et al. (2003[Chen, Y., Zhang, L. & Chen, Z. (2003). Acta Cryst. E59, m429-m430.]); Olmstead et al. (2003[Olmstead, M. M., Troeltzsch, C. & Patten, T. E. (2003). Acta Cryst. E59, m502-m503.]); Vergeer et al. (1999[Vergeer, P., Kooijman, H., Schreurs, A. M. M., Kroon, J. & Grech, E. (1999). Acta Cryst. C55, 1822-1824.]).

[Scheme 1]

Experimental

Crystal data
  • C15H20N2O4

  • Mr = 292.33

  • Orthorhombic, P b c a

  • a = 9.675 (2) Å

  • b = 13.137 (3) Å

  • c = 23.128 (5) Å

  • V = 2939.7 (12) Å3

  • Z = 8

  • Mo Kα radiation

  • μ = 0.10 mm−1

  • T = 103 K

  • 0.43 × 0.40 × 0.18 mm

Data collection
  • Rigaku SPIDER diffractometer

  • 20907 measured reflections

  • 3367 independent reflections

  • 3005 reflections with I > 2σ(I)

  • Rint = 0.039

Refinement
  • R[F2 > 2σ(F2)] = 0.048

  • wR(F2) = 0.114

  • S = 1.00

  • 3367 reflections

  • 198 parameters

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

  • Δρmax = 0.29 e Å−3

  • Δρmin = −0.28 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N2—H2N⋯O4i 0.879 (19) 2.051 (19) 2.9251 (17) 173.1 (16)
C5—H5⋯O4 0.95 2.27 2.8771 (19) 121
C11—H11B⋯O3ii 0.98 2.49 3.456 (2) 168
Symmetry codes: (i) [x+{\script{1\over 2}}, y, -z+{\script{3\over 2}}]; (ii) [-x+{\script{3\over 2}}, y+{\script{1\over 2}}, z].

Data collection: RAPID-AUTO (Rigaku, 2004[Rigaku (2004). RAPID-AUTO. Rigaku Corporation, Tokyo, Japan.]); cell refinement: RAPID-AUTO; data reduction: RAPID-AUTO; 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: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: SHELXTL.

Supporting information


Comment top

The stucture of the title compound, (I), is an important phenylmorpholine product. Phenylmorpholine compounds are used as α2 C adrenergic receptor agonists. Numerous phenylmorpholine derivatives possess various pharmacological properties (Bourlot, et al., 1998; Albanese, et al., 2003; La et al., 2008).

We report here the crystal structure of the title compound. (Fig. 1). The title molecule of (I) contains a benzene ring fused to an oxazine ring and one tert-butoxycarbonyl bound to the N atom. The N1—C8 bond distance is 1.4208 (18) Å and agrees with literature values (Vergeer, et al., 1999; Chen, et al., 2003; Olmstead, et al., 2003). The conformation of the six-membered heterocyclic ring shows that C1 and C2 are out of the plane of the remaining four atoms by 0.5950 (16) and -0.0818 (16) Å, respectively.

The molecules are linked through hydrogen-bonding interactions of types N—H···O and C—H···O (Table 1).

Related literature top

For the pharmacological properties of phenylmorpholine derivatives, see: Bourlot et al. (1998); Albanese et al. (2003); La et al. (2008). For structures, see: Chen et al. (2003); Olmstead et al. (2003); Vergeer et al. (1999).

Experimental top

The title compound was crystallized from a mixed solvent composed of dichloromethane and hexane (1:1); colorlessblock-shaped crystals were obtained after several days.

Refinement top

Positional parameters of all the H atomsbonded to C atoms were calculated geometrically and were allowed to ride on the C atoms to which they were bonded, with C—H distances of 0.95Å (CH), 0.98Å (CH3) or 0.99Å (CH2), and with Uiso(H) =1.2Ueqof the parent atoms. The H-atoms bonded to N atoms was taken from a difference map and was allowed to refine freely.

Computing details top

Data collection: RAPID-AUTO (Rigaku, 2004); cell refinement: RAPID-AUTO (Rigaku, 2004); data reduction: RAPID-AUTO (Rigaku, 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. A view of the title compound with the atomic numbering scheme. Displacement ellipsoids were drawn at the 50% probability level.
tert-Butyl 6-acetamido-3,4-dihydro-2H-1,4-benzoxazine-4-carboxylate top
Crystal data top
C15H20N2O4F(000) = 1248
Mr = 292.33Dx = 1.321 Mg m3
Orthorhombic, PbcaMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ac 2abCell parameters from 8192 reflections
a = 9.675 (2) Åθ = 3.1–27.5°
b = 13.137 (3) ŵ = 0.10 mm1
c = 23.128 (5) ÅT = 103 K
V = 2939.7 (12) Å3Chunk, colorless
Z = 80.43 × 0.40 × 0.18 mm
Data collection top
Rigaku SPIDER
diffractometer
3005 reflections with I > 2σ(I)
Radiation source: Rotating AnodeRint = 0.039
Graphite monochromatorθmax = 27.5°, θmin = 3.1°
ω scansh = 1212
20907 measured reflectionsk = 1617
3367 independent reflectionsl = 2929
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)] = 0.048Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.114H atoms treated by a mixture of independent and constrained refinement
S = 1.00 w = 1/[σ2(Fo2) + (0.0536P)2 + 1.960P]
where P = (Fo2 + 2Fc2)/3
3367 reflections(Δ/σ)max < 0.001
198 parametersΔρmax = 0.29 e Å3
0 restraintsΔρmin = 0.28 e Å3
Crystal data top
C15H20N2O4V = 2939.7 (12) Å3
Mr = 292.33Z = 8
Orthorhombic, PbcaMo Kα radiation
a = 9.675 (2) ŵ = 0.10 mm1
b = 13.137 (3) ÅT = 103 K
c = 23.128 (5) Å0.43 × 0.40 × 0.18 mm
Data collection top
Rigaku SPIDER
diffractometer
3005 reflections with I > 2σ(I)
20907 measured reflectionsRint = 0.039
3367 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0480 restraints
wR(F2) = 0.114H atoms treated by a mixture of independent and constrained refinement
S = 1.00Δρmax = 0.29 e Å3
3367 reflectionsΔρmin = 0.28 e Å3
198 parameters
Special details top

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
O10.16030 (11)0.52261 (8)0.61658 (5)0.0221 (3)
O20.53747 (10)0.73649 (7)0.57927 (4)0.0173 (2)
O30.62739 (12)0.58152 (8)0.55786 (5)0.0239 (3)
O40.08299 (11)0.93078 (8)0.77211 (5)0.0222 (3)
N10.43426 (13)0.59636 (9)0.61318 (5)0.0164 (3)
N20.28810 (12)0.88225 (9)0.73211 (5)0.0146 (3)
C10.40682 (16)0.48702 (11)0.61007 (7)0.0201 (3)
H1A0.41100.45690.64930.024*
H1B0.47750.45340.58570.024*
C20.26528 (17)0.47066 (11)0.58444 (7)0.0212 (3)
H2A0.26470.49540.54400.025*
H2B0.24450.39690.58390.025*
C30.19649 (15)0.61199 (11)0.64273 (6)0.0162 (3)
C40.09200 (15)0.66258 (11)0.67188 (6)0.0178 (3)
H40.00140.63480.67180.021*
C50.11645 (15)0.75263 (11)0.70112 (6)0.0166 (3)
H50.04310.78720.72000.020*
C60.25037 (15)0.79196 (10)0.70245 (6)0.0140 (3)
C70.35627 (14)0.74149 (10)0.67329 (6)0.0145 (3)
H70.44750.76810.67450.017*
C80.33000 (15)0.65256 (11)0.64237 (6)0.0145 (3)
C90.54187 (15)0.63514 (11)0.58119 (6)0.0159 (3)
C100.65864 (16)0.79588 (12)0.56032 (7)0.0200 (3)
C110.60965 (17)0.90434 (11)0.56794 (7)0.0237 (3)
H11A0.53210.91740.54170.028*
H11B0.68550.95120.55910.028*
H11C0.57960.91460.60800.028*
C120.6938 (3)0.77433 (14)0.49806 (9)0.0433 (5)
H12A0.72740.70430.49440.052*
H12B0.76580.82160.48510.052*
H12C0.61110.78310.47410.052*
C130.7775 (2)0.77283 (15)0.60145 (11)0.0425 (5)
H13A0.74670.78250.64140.051*
H13B0.85480.81890.59330.051*
H13C0.80770.70220.59610.051*
C140.20747 (14)0.94428 (11)0.76449 (6)0.0155 (3)
C150.28116 (15)1.03281 (11)0.79194 (6)0.0188 (3)
H15A0.24061.09660.77800.023*
H15B0.37931.03060.78160.023*
H15C0.27151.02890.83410.023*
H2N0.375 (2)0.9008 (13)0.7287 (8)0.022 (5)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0204 (6)0.0195 (5)0.0263 (6)0.0049 (4)0.0015 (4)0.0083 (4)
O20.0147 (5)0.0148 (5)0.0224 (5)0.0012 (4)0.0056 (4)0.0001 (4)
O30.0232 (6)0.0193 (5)0.0292 (6)0.0037 (5)0.0103 (5)0.0013 (5)
O40.0124 (5)0.0268 (6)0.0275 (6)0.0001 (4)0.0030 (4)0.0073 (5)
N10.0167 (6)0.0136 (6)0.0189 (6)0.0006 (5)0.0039 (5)0.0008 (5)
N20.0107 (6)0.0153 (6)0.0179 (6)0.0017 (5)0.0012 (4)0.0010 (5)
C10.0240 (8)0.0134 (7)0.0230 (8)0.0007 (6)0.0048 (6)0.0001 (6)
C20.0268 (8)0.0163 (7)0.0205 (7)0.0020 (6)0.0038 (6)0.0035 (6)
C30.0188 (7)0.0153 (7)0.0145 (6)0.0021 (6)0.0023 (5)0.0000 (5)
C40.0128 (7)0.0205 (7)0.0202 (7)0.0035 (6)0.0006 (5)0.0001 (6)
C50.0120 (6)0.0187 (7)0.0191 (7)0.0006 (5)0.0022 (5)0.0001 (5)
C60.0151 (7)0.0150 (6)0.0119 (6)0.0003 (5)0.0001 (5)0.0016 (5)
C70.0125 (7)0.0164 (7)0.0146 (6)0.0016 (5)0.0004 (5)0.0020 (5)
C80.0144 (7)0.0159 (7)0.0130 (6)0.0019 (5)0.0016 (5)0.0020 (5)
C90.0156 (7)0.0167 (7)0.0153 (6)0.0014 (6)0.0011 (5)0.0005 (5)
C100.0166 (7)0.0195 (7)0.0237 (8)0.0036 (6)0.0076 (6)0.0011 (6)
C110.0250 (8)0.0182 (7)0.0280 (8)0.0039 (6)0.0068 (6)0.0011 (6)
C120.0707 (15)0.0260 (9)0.0330 (10)0.0041 (10)0.0303 (10)0.0012 (8)
C130.0241 (10)0.0336 (10)0.0697 (15)0.0061 (8)0.0121 (9)0.0070 (10)
C140.0146 (7)0.0170 (7)0.0148 (7)0.0012 (5)0.0007 (5)0.0020 (5)
C150.0169 (7)0.0198 (7)0.0197 (7)0.0007 (6)0.0016 (5)0.0034 (6)
Geometric parameters (Å, º) top
O1—C31.3664 (17)C5—C61.395 (2)
O1—C21.4317 (18)C5—H50.9500
O2—C91.3328 (18)C6—C71.394 (2)
O2—C101.4749 (17)C7—C81.393 (2)
O3—C91.2132 (18)C7—H70.9500
O4—C141.2301 (18)C10—C121.506 (2)
N1—C91.3752 (19)C10—C111.512 (2)
N1—C81.4208 (18)C10—C131.523 (2)
N1—C11.4624 (19)C11—H11A0.9800
N2—C141.3540 (18)C11—H11B0.9800
N2—C61.4180 (18)C11—H11C0.9800
N2—H2N0.88 (2)C12—H12A0.9800
C1—C21.508 (2)C12—H12B0.9800
C1—H1A0.9900C12—H12C0.9800
C1—H1B0.9900C13—H13A0.9800
C2—H2A0.9900C13—H13B0.9800
C2—H2B0.9900C13—H13C0.9800
C3—C41.385 (2)C14—C151.505 (2)
C3—C81.398 (2)C15—H15A0.9800
C4—C51.383 (2)C15—H15B0.9800
C4—H40.9500C15—H15C0.9800
C3—O1—C2117.24 (12)C3—C8—N1117.45 (13)
C9—O2—C10120.86 (11)O3—C9—O2125.95 (14)
C9—N1—C8126.92 (12)O3—C9—N1122.72 (13)
C9—N1—C1118.35 (12)O2—C9—N1111.33 (12)
C8—N1—C1113.88 (12)O2—C10—C12111.35 (14)
C14—N2—C6128.51 (12)O2—C10—C11102.40 (12)
C14—N2—H2N115.7 (12)C12—C10—C11111.06 (14)
C6—N2—H2N115.8 (12)O2—C10—C13108.04 (13)
N1—C1—C2108.92 (12)C12—C10—C13112.90 (17)
N1—C1—H1A109.9C11—C10—C13110.57 (14)
C2—C1—H1A109.9C10—C11—H11A109.5
N1—C1—H1B109.9C10—C11—H11B109.5
C2—C1—H1B109.9H11A—C11—H11B109.5
H1A—C1—H1B108.3C10—C11—H11C109.5
O1—C2—C1111.86 (12)H11A—C11—H11C109.5
O1—C2—H2A109.2H11B—C11—H11C109.5
C1—C2—H2A109.2C10—C12—H12A109.5
O1—C2—H2B109.2C10—C12—H12B109.5
C1—C2—H2B109.2H12A—C12—H12B109.5
H2A—C2—H2B107.9C10—C12—H12C109.5
O1—C3—C4116.16 (13)H12A—C12—H12C109.5
O1—C3—C8124.19 (13)H12B—C12—H12C109.5
C4—C3—C8119.64 (13)C10—C13—H13A109.5
C5—C4—C3121.58 (13)C10—C13—H13B109.5
C5—C4—H4119.2H13A—C13—H13B109.5
C3—C4—H4119.2C10—C13—H13C109.5
C4—C5—C6119.10 (13)H13A—C13—H13C109.5
C4—C5—H5120.4H13B—C13—H13C109.5
C6—C5—H5120.4O4—C14—N2123.82 (13)
C7—C6—C5119.71 (13)O4—C14—C15121.00 (13)
C7—C6—N2116.27 (13)N2—C14—C15115.18 (12)
C5—C6—N2124.02 (13)C14—C15—H15A109.5
C8—C7—C6120.86 (13)C14—C15—H15B109.5
C8—C7—H7119.6H15A—C15—H15B109.5
C6—C7—H7119.6C14—C15—H15C109.5
C7—C8—C3119.04 (13)H15A—C15—H15C109.5
C7—C8—N1123.38 (13)H15B—C15—H15C109.5
C9—N1—C1—C2116.78 (14)C4—C3—C8—C72.4 (2)
C8—N1—C1—C253.44 (16)O1—C3—C8—N10.5 (2)
C3—O1—C2—C132.01 (17)C4—C3—C8—N1178.35 (12)
N1—C1—C2—O156.42 (16)C9—N1—C8—C741.1 (2)
C2—O1—C3—C4177.85 (13)C1—N1—C8—C7149.70 (13)
C2—O1—C3—C83.3 (2)C9—N1—C8—C3143.12 (14)
O1—C3—C4—C5178.58 (13)C1—N1—C8—C326.10 (18)
C8—C3—C4—C50.3 (2)C10—O2—C9—O315.9 (2)
C3—C4—C5—C61.6 (2)C10—O2—C9—N1164.66 (12)
C4—C5—C6—C71.5 (2)C8—N1—C9—O3179.49 (14)
C4—C5—C6—N2178.52 (13)C1—N1—C9—O311.7 (2)
C14—N2—C6—C7178.52 (13)C8—N1—C9—O21.1 (2)
C14—N2—C6—C51.5 (2)C1—N1—C9—O2167.70 (12)
C5—C6—C7—C80.5 (2)C9—O2—C10—C1264.04 (18)
N2—C6—C7—C8179.43 (12)C9—O2—C10—C11177.21 (13)
C6—C7—C8—C32.5 (2)C9—O2—C10—C1360.47 (18)
C6—C7—C8—N1178.20 (12)C6—N2—C14—O41.4 (2)
O1—C3—C8—C7176.45 (13)C6—N2—C14—C15178.02 (13)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N2—H2N···O4i0.879 (19)2.051 (19)2.9251 (17)173.1 (16)
C1—H1B···O30.992.312.748 (2)105
C5—H5···O40.952.272.8771 (19)121
C7—H7···O20.952.402.7940 (18)104
C11—H11B···O3ii0.982.493.456 (2)168
C12—H12A···O30.982.392.957 (2)117
C13—H13C···O30.982.523.073 (2)116
Symmetry codes: (i) x+1/2, y, z+3/2; (ii) x+3/2, y+1/2, z.

Experimental details

Crystal data
Chemical formulaC15H20N2O4
Mr292.33
Crystal system, space groupOrthorhombic, Pbca
Temperature (K)103
a, b, c (Å)9.675 (2), 13.137 (3), 23.128 (5)
V3)2939.7 (12)
Z8
Radiation typeMo Kα
µ (mm1)0.10
Crystal size (mm)0.43 × 0.40 × 0.18
Data collection
DiffractometerRigaku SPIDER
diffractometer
Absorption correction
No. of measured, independent and
observed [I > 2σ(I)] reflections
20907, 3367, 3005
Rint0.039
(sin θ/λ)max1)0.649
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.048, 0.114, 1.00
No. of reflections3367
No. of parameters198
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.29, 0.28

Computer programs: RAPID-AUTO (Rigaku, 2004), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N2—H2N···O4i0.879 (19)2.051 (19)2.9251 (17)173.1 (16)
C5—H5···O40.952.272.8771 (19)121
C11—H11B···O3ii0.982.493.456 (2)168
Symmetry codes: (i) x+1/2, y, z+3/2; (ii) x+3/2, y+1/2, z.
 

Acknowledgements

This work was supported financially by Jiangsu Province 's Key Medical Talents Program (No. RC2007097).

References

First citationAlbanese, D., Landini, D., Lupi, V. & Penso, M. (2003). Ind. Eng. Chem. Res. 42, 680–686.  Web of Science CrossRef CAS Google Scholar
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