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

Gu, X.-B.

doi:10.1107/S1600536810036937

organic compounds

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ISSN: 2056-9890

Volume 66| Part 10| October 2010| Page o2600

doi:10.1107/S1600536810036937

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

Xiao-Bo Gu ^a ^*

^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 ); Albanese et al. (2003 ); La et al. (2008 ). For structures, see: Chen et al. (2003 ); Olmstead et al. (2003 ); Vergeer et al. (1999 ).

Experimental

Crystal data

C₁₅H₂₀N₂O₄
M_r = 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)
R_int = 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
Δρ_max = 0.29 e Å⁻³
Δρ_min = −0.28 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	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 ); cell refinement: RAPID-AUTO; data reduction: RAPID-AUTO; 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.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536810036937/jh2200sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536810036937/jh2200Isup2.hkl

checkCIF report

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.

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

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

C₁₅H₂₀N₂O₄	F(000) = 1248
M_r = 292.33	D_x = 1.321 Mg m⁻³
Orthorhombic, Pbca	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ac 2ab	Cell parameters from 8192 reflections
a = 9.675 (2) Å	θ = 3.1–27.5°
b = 13.137 (3) Å	µ = 0.10 mm⁻¹
c = 23.128 (5) Å	T = 103 K
V = 2939.7 (12) Å³	Chunk, colorless
Z = 8	0.43 × 0.40 × 0.18 mm

Data collection top

Rigaku SPIDER diffractometer	3005 reflections with I > 2σ(I)
Radiation source: Rotating Anode	R_int = 0.039
Graphite monochromator	θ_max = 27.5°, θ_min = 3.1°
ω scans	h = −12→12
20907 measured reflections	k = −16→17
3367 independent reflections	l = −29→29

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.048	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.114	H atoms treated by a mixture of independent and constrained refinement
S = 1.00	w = 1/[σ²(F_o²) + (0.0536P)² + 1.960P] where P = (F_o² + 2F_c²)/3
3367 reflections	(Δ/σ)_max < 0.001
198 parameters	Δρ_max = 0.29 e Å⁻³
0 restraints	Δρ_min = −0.28 e Å⁻³

Crystal data top

C₁₅H₂₀N₂O₄	V = 2939.7 (12) Å³
M_r = 292.33	Z = 8
Orthorhombic, Pbca	Mo Kα radiation
a = 9.675 (2) Å	µ = 0.10 mm⁻¹
b = 13.137 (3) Å	T = 103 K
c = 23.128 (5) Å	0.43 × 0.40 × 0.18 mm

Data collection top

Rigaku SPIDER diffractometer	3005 reflections with I > 2σ(I)
20907 measured reflections	R_int = 0.039
3367 independent reflections

Refinement top

R[F² > 2σ(F²)] = 0.048	0 restraints
wR(F²) = 0.114	H atoms treated by a mixture of independent and constrained refinement
S = 1.00	Δρ_max = 0.29 e Å⁻³
3367 reflections	Δρ_min = −0.28 e Å⁻³
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

	x	y	z	U_iso*/U_eq
O1	0.16030 (11)	0.52261 (8)	0.61658 (5)	0.0221 (3)
O2	0.53747 (10)	0.73649 (7)	0.57927 (4)	0.0173 (2)
O3	0.62739 (12)	0.58152 (8)	0.55786 (5)	0.0239 (3)
O4	0.08299 (11)	0.93078 (8)	0.77211 (5)	0.0222 (3)
N1	0.43426 (13)	0.59636 (9)	0.61318 (5)	0.0164 (3)
N2	0.28810 (12)	0.88225 (9)	0.73211 (5)	0.0146 (3)
C1	0.40682 (16)	0.48702 (11)	0.61007 (7)	0.0201 (3)
H1A	0.4110	0.4569	0.6493	0.024*
H1B	0.4775	0.4534	0.5857	0.024*
C2	0.26528 (17)	0.47066 (11)	0.58444 (7)	0.0212 (3)
H2A	0.2647	0.4954	0.5440	0.025*
H2B	0.2445	0.3969	0.5839	0.025*
C3	0.19649 (15)	0.61199 (11)	0.64273 (6)	0.0162 (3)
C4	0.09200 (15)	0.66258 (11)	0.67188 (6)	0.0178 (3)
H4	0.0014	0.6348	0.6718	0.021*
C5	0.11645 (15)	0.75263 (11)	0.70112 (6)	0.0166 (3)
H5	0.0431	0.7872	0.7200	0.020*
C6	0.25037 (15)	0.79196 (10)	0.70245 (6)	0.0140 (3)
C7	0.35627 (14)	0.74149 (10)	0.67329 (6)	0.0145 (3)
H7	0.4475	0.7681	0.6745	0.017*
C8	0.33000 (15)	0.65256 (11)	0.64237 (6)	0.0145 (3)
C9	0.54187 (15)	0.63514 (11)	0.58119 (6)	0.0159 (3)
C10	0.65864 (16)	0.79588 (12)	0.56032 (7)	0.0200 (3)
C11	0.60965 (17)	0.90434 (11)	0.56794 (7)	0.0237 (3)
H11A	0.5321	0.9174	0.5417	0.028*
H11B	0.6855	0.9512	0.5591	0.028*
H11C	0.5796	0.9146	0.6080	0.028*
C12	0.6938 (3)	0.77433 (14)	0.49806 (9)	0.0433 (5)
H12A	0.7274	0.7043	0.4944	0.052*
H12B	0.7658	0.8216	0.4851	0.052*
H12C	0.6111	0.7831	0.4741	0.052*
C13	0.7775 (2)	0.77283 (15)	0.60145 (11)	0.0425 (5)
H13A	0.7467	0.7825	0.6414	0.051*
H13B	0.8548	0.8189	0.5933	0.051*
H13C	0.8077	0.7022	0.5961	0.051*
C14	0.20747 (14)	0.94428 (11)	0.76449 (6)	0.0155 (3)
C15	0.28116 (15)	1.03281 (11)	0.79194 (6)	0.0188 (3)
H15A	0.2406	1.0966	0.7780	0.023*
H15B	0.3793	1.0306	0.7816	0.023*
H15C	0.2715	1.0289	0.8341	0.023*
H2N	0.375 (2)	0.9008 (13)	0.7287 (8)	0.022 (5)*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.0204 (6)	0.0195 (5)	0.0263 (6)	−0.0049 (4)	0.0015 (4)	−0.0083 (4)
O2	0.0147 (5)	0.0148 (5)	0.0224 (5)	−0.0012 (4)	0.0056 (4)	0.0001 (4)
O3	0.0232 (6)	0.0193 (5)	0.0292 (6)	0.0037 (5)	0.0103 (5)	−0.0013 (5)
O4	0.0124 (5)	0.0268 (6)	0.0275 (6)	−0.0001 (4)	0.0030 (4)	−0.0073 (5)
N1	0.0167 (6)	0.0136 (6)	0.0189 (6)	0.0006 (5)	0.0039 (5)	−0.0008 (5)
N2	0.0107 (6)	0.0153 (6)	0.0179 (6)	−0.0017 (5)	0.0012 (4)	−0.0010 (5)
C1	0.0240 (8)	0.0134 (7)	0.0230 (8)	0.0007 (6)	0.0048 (6)	0.0001 (6)
C2	0.0268 (8)	0.0163 (7)	0.0205 (7)	−0.0020 (6)	0.0038 (6)	−0.0035 (6)
C3	0.0188 (7)	0.0153 (7)	0.0145 (6)	−0.0021 (6)	−0.0023 (5)	0.0000 (5)
C4	0.0128 (7)	0.0205 (7)	0.0202 (7)	−0.0035 (6)	−0.0006 (5)	0.0001 (6)
C5	0.0120 (6)	0.0187 (7)	0.0191 (7)	−0.0006 (5)	0.0022 (5)	−0.0001 (5)
C6	0.0151 (7)	0.0150 (6)	0.0119 (6)	−0.0003 (5)	−0.0001 (5)	0.0016 (5)
C7	0.0125 (7)	0.0164 (7)	0.0146 (6)	−0.0016 (5)	0.0004 (5)	0.0020 (5)
C8	0.0144 (7)	0.0159 (7)	0.0130 (6)	0.0019 (5)	0.0016 (5)	0.0020 (5)
C9	0.0156 (7)	0.0167 (7)	0.0153 (6)	0.0014 (6)	−0.0011 (5)	0.0005 (5)
C10	0.0166 (7)	0.0195 (7)	0.0237 (8)	−0.0036 (6)	0.0076 (6)	0.0011 (6)
C11	0.0250 (8)	0.0182 (7)	0.0280 (8)	−0.0039 (6)	0.0068 (6)	−0.0011 (6)
C12	0.0707 (15)	0.0260 (9)	0.0330 (10)	−0.0041 (10)	0.0303 (10)	−0.0012 (8)
C13	0.0241 (10)	0.0336 (10)	0.0697 (15)	−0.0061 (8)	−0.0121 (9)	0.0070 (10)
C14	0.0146 (7)	0.0170 (7)	0.0148 (7)	0.0012 (5)	−0.0007 (5)	0.0020 (5)
C15	0.0169 (7)	0.0198 (7)	0.0197 (7)	−0.0007 (6)	0.0016 (5)	−0.0034 (6)

Geometric parameters (Å, º) top

O1—C3	1.3664 (17)	C5—C6	1.395 (2)
O1—C2	1.4317 (18)	C5—H5	0.9500
O2—C9	1.3328 (18)	C6—C7	1.394 (2)
O2—C10	1.4749 (17)	C7—C8	1.393 (2)
O3—C9	1.2132 (18)	C7—H7	0.9500
O4—C14	1.2301 (18)	C10—C12	1.506 (2)
N1—C9	1.3752 (19)	C10—C11	1.512 (2)
N1—C8	1.4208 (18)	C10—C13	1.523 (2)
N1—C1	1.4624 (19)	C11—H11A	0.9800
N2—C14	1.3540 (18)	C11—H11B	0.9800
N2—C6	1.4180 (18)	C11—H11C	0.9800
N2—H2N	0.88 (2)	C12—H12A	0.9800
C1—C2	1.508 (2)	C12—H12B	0.9800
C1—H1A	0.9900	C12—H12C	0.9800
C1—H1B	0.9900	C13—H13A	0.9800
C2—H2A	0.9900	C13—H13B	0.9800
C2—H2B	0.9900	C13—H13C	0.9800
C3—C4	1.385 (2)	C14—C15	1.505 (2)
C3—C8	1.398 (2)	C15—H15A	0.9800
C4—C5	1.383 (2)	C15—H15B	0.9800
C4—H4	0.9500	C15—H15C	0.9800

C3—O1—C2	117.24 (12)	C3—C8—N1	117.45 (13)
C9—O2—C10	120.86 (11)	O3—C9—O2	125.95 (14)
C9—N1—C8	126.92 (12)	O3—C9—N1	122.72 (13)
C9—N1—C1	118.35 (12)	O2—C9—N1	111.33 (12)
C8—N1—C1	113.88 (12)	O2—C10—C12	111.35 (14)
C14—N2—C6	128.51 (12)	O2—C10—C11	102.40 (12)
C14—N2—H2N	115.7 (12)	C12—C10—C11	111.06 (14)
C6—N2—H2N	115.8 (12)	O2—C10—C13	108.04 (13)
N1—C1—C2	108.92 (12)	C12—C10—C13	112.90 (17)
N1—C1—H1A	109.9	C11—C10—C13	110.57 (14)
C2—C1—H1A	109.9	C10—C11—H11A	109.5
N1—C1—H1B	109.9	C10—C11—H11B	109.5
C2—C1—H1B	109.9	H11A—C11—H11B	109.5
H1A—C1—H1B	108.3	C10—C11—H11C	109.5
O1—C2—C1	111.86 (12)	H11A—C11—H11C	109.5
O1—C2—H2A	109.2	H11B—C11—H11C	109.5
C1—C2—H2A	109.2	C10—C12—H12A	109.5
O1—C2—H2B	109.2	C10—C12—H12B	109.5
C1—C2—H2B	109.2	H12A—C12—H12B	109.5
H2A—C2—H2B	107.9	C10—C12—H12C	109.5
O1—C3—C4	116.16 (13)	H12A—C12—H12C	109.5
O1—C3—C8	124.19 (13)	H12B—C12—H12C	109.5
C4—C3—C8	119.64 (13)	C10—C13—H13A	109.5
C5—C4—C3	121.58 (13)	C10—C13—H13B	109.5
C5—C4—H4	119.2	H13A—C13—H13B	109.5
C3—C4—H4	119.2	C10—C13—H13C	109.5
C4—C5—C6	119.10 (13)	H13A—C13—H13C	109.5
C4—C5—H5	120.4	H13B—C13—H13C	109.5
C6—C5—H5	120.4	O4—C14—N2	123.82 (13)
C7—C6—C5	119.71 (13)	O4—C14—C15	121.00 (13)
C7—C6—N2	116.27 (13)	N2—C14—C15	115.18 (12)
C5—C6—N2	124.02 (13)	C14—C15—H15A	109.5
C8—C7—C6	120.86 (13)	C14—C15—H15B	109.5
C8—C7—H7	119.6	H15A—C15—H15B	109.5
C6—C7—H7	119.6	C14—C15—H15C	109.5
C7—C8—C3	119.04 (13)	H15A—C15—H15C	109.5
C7—C8—N1	123.38 (13)	H15B—C15—H15C	109.5

C9—N1—C1—C2	−116.78 (14)	C4—C3—C8—C7	2.4 (2)
C8—N1—C1—C2	53.44 (16)	O1—C3—C8—N1	−0.5 (2)
C3—O1—C2—C1	32.01 (17)	C4—C3—C8—N1	178.35 (12)
N1—C1—C2—O1	−56.42 (16)	C9—N1—C8—C7	−41.1 (2)
C2—O1—C3—C4	177.85 (13)	C1—N1—C8—C7	149.70 (13)
C2—O1—C3—C8	−3.3 (2)	C9—N1—C8—C3	143.12 (14)
O1—C3—C4—C5	178.58 (13)	C1—N1—C8—C3	−26.10 (18)
C8—C3—C4—C5	−0.3 (2)	C10—O2—C9—O3	−15.9 (2)
C3—C4—C5—C6	−1.6 (2)	C10—O2—C9—N1	164.66 (12)
C4—C5—C6—C7	1.5 (2)	C8—N1—C9—O3	179.49 (14)
C4—C5—C6—N2	−178.52 (13)	C1—N1—C9—O3	−11.7 (2)
C14—N2—C6—C7	−178.52 (13)	C8—N1—C9—O2	−1.1 (2)
C14—N2—C6—C5	1.5 (2)	C1—N1—C9—O2	167.70 (12)
C5—C6—C7—C8	0.5 (2)	C9—O2—C10—C12	64.04 (18)
N2—C6—C7—C8	−179.43 (12)	C9—O2—C10—C11	−177.21 (13)
C6—C7—C8—C3	−2.5 (2)	C9—O2—C10—C13	−60.47 (18)
C6—C7—C8—N1	−178.20 (12)	C6—N2—C14—O4	−1.4 (2)
O1—C3—C8—C7	−176.45 (13)	C6—N2—C14—C15	178.02 (13)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N2—H2N···O4ⁱ	0.879 (19)	2.051 (19)	2.9251 (17)	173.1 (16)
C1—H1B···O3	0.99	2.31	2.748 (2)	105
C5—H5···O4	0.95	2.27	2.8771 (19)	121
C7—H7···O2	0.95	2.40	2.7940 (18)	104
C11—H11B···O3ⁱⁱ	0.98	2.49	3.456 (2)	168
C12—H12A···O3	0.98	2.39	2.957 (2)	117
C13—H13C···O3	0.98	2.52	3.073 (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 formula	C₁₅H₂₀N₂O₄
M_r	292.33
Crystal system, space group	Orthorhombic, Pbca
Temperature (K)	103
a, b, c (Å)	9.675 (2), 13.137 (3), 23.128 (5)
V (Å³)	2939.7 (12)
Z	8
Radiation type	Mo Kα
µ (mm⁻¹)	0.10
Crystal size (mm)	0.43 × 0.40 × 0.18

Data collection
Diffractometer	Rigaku SPIDER diffractometer
Absorption correction	–
No. of measured, independent and observed [I > 2σ(I)] reflections	20907, 3367, 3005
R_int	0.039
(sin θ/λ)_max (Å⁻¹)	0.649

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.048, 0.114, 1.00
No. of reflections	3367
No. of parameters	198
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	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···A	D—H	H···A	D···A	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+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).

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