(1S,2R,4S,5R)-tert-Butyl 7-oxo-3-oxa-6-aza­tri­cyclo­[3.2.1.0^2,4]­octane-6-carboxyl­ate

The tricyclic title compound, C₁₁H₁₅NO₄, is an intermediate in the synthesis of (1S,2R,4R)-4-amino-2-(hydroxy­methyl)­cyclo­pentanol, which is an important carbocyclic analogue of β-2-deoxy­ribosyl­amine. All bond lengths and angles in the `exo epoxide' are in normal ranges.

Key indicators

• Single-crystal X-ray study
• T = 193 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.031
• wR factor = 0.074
• Data-to-parameter ratio = 8.1

checkCIF/PLATON results

No syntax errors found



Alert level C
REFLT03_ALERT_1_C  Reflection count < 95% complete
           From the CIF: _diffrn_reflns_theta_max           25.73
           From the CIF: _diffrn_reflns_theta_full           0.00
           From the CIF: _reflns_number_total               1170
           TEST2: Reflns within _diffrn_reflns_theta_max
           Count of symmetry unique reflns         1252
           Completeness (_total/calc)             93.45%
PLAT022_ALERT_3_C Ratio Unique / Expected Reflections too Low ....       0.94
PLAT028_ALERT_3_C _diffrn_measured_fraction_theta_max  Low .......       0.93

Alert level G
REFLT03_ALERT_4_G Please check that the estimate of the number of Friedel pairs is
            correct. If it is not, please give the correct count in the
            _publ_section_exptl_refinement section of the submitted CIF.
           From the CIF: _diffrn_reflns_theta_max           25.73
           From the CIF: _reflns_number_total               1170
           Count of symmetry unique reflns         1252
           Completeness (_total/calc)             93.45%
           TEST3: Check Friedels for noncentro structure
           Estimate of Friedel pairs measured         0
           Fraction of Friedel pairs measured     0.000
           Are heavy atom types Z>Si present           no

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   3 ALERT level C = Check and explain
   1 ALERT level G = General alerts; check

   1 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   0 ALERT type 2 Indicator that the structure model may be wrong or deficient
   2 ALERT type 3 Indicator that the structure quality may be low
   1 ALERT type 4 Improvement, methodology, query or suggestion

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Computing details

Data collection: X-AREA (Stoe & Cie, 2003); cell refinement: X-AREA; data reduction: X-AREA; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: DIAMOND (Brandenburg, 2001); software used to prepare material for publication: WinGX (Farrugia, 1999).

(I)

Crystal data

C11H15NO4	F(000) = 480
Mr = 225.24	Dx = 1.362 Mg m^−3
Orthorhombic, P212121	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2ab	Cell parameters from 7535 reflections
a = 5.8200 (3) Å	θ = 2.5–25.7°
b = 8.0891 (5) Å	µ = 0.10 mm^−1
c = 23.3254 (18) Å	T = 193 K
V = 1098.13 (12) Å^3	Prism, colourless
Z = 4	0.3 × 0.26 × 0.2 mm

Data collection

Stoe IPDS-II diffractometer	992 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.064
Graphite monochromator	θmax = 25.7°, θmin = 2.7°
ω scans	h = −6→7
5125 measured reflections	k = −9→9
1170 independent reflections	l = −28→28

Refinement

Refinement on F^2	0 restraints
Least-squares matrix: full	Hydrogen site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.031	Riding
wR(F^2) = 0.074	w = 1/[σ^2(Fo^2) + (0.0462P)^2] where P = (Fo^2 + 2Fc^2)/3
S = 1.01	(Δ/σ)max < 0.001
1170 reflections	Δρmax = 0.13 e Å^−3
145 parameters	Δρmin = −0.15 e Å^−3

Special details

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
O1	0.3162 (2)	0.26513 (18)	0.15470 (5)	0.0302 (4)
C1	0.6002 (3)	−0.1489 (3)	0.06950 (8)	0.0287 (5)
H1	0.5601	−0.2629	0.0728	0.034*
O2	0.5339 (3)	0.4038 (2)	0.08969 (6)	0.0374 (4)
C2	0.8474 (3)	−0.1043 (3)	0.08741 (8)	0.0306 (5)
H2	0.9125	−0.1429	0.1215	0.037*
O3	1.0041 (2)	−0.0779 (2)	0.04031 (6)	0.0373 (4)
O4	0.3452 (2)	−0.07119 (19)	0.14996 (5)	0.0321 (4)
C4	0.8873 (3)	0.0604 (3)	0.06552 (8)	0.0284 (5)
H4	0.9724	0.1412	0.0828	0.034*
C5	0.6594 (3)	0.1063 (3)	0.03654 (7)	0.0277 (5)
H5	0.6566	0.2039	0.0124	0.033*
N6	0.4983 (3)	0.1243 (2)	0.08592 (6)	0.0243 (4)
C7	0.4589 (3)	−0.0354 (3)	0.10834 (8)	0.0240 (5)
C8	0.5789 (3)	−0.0581 (3)	0.01254 (8)	0.0318 (6)
H82	0.6908	−0.0959	−0.0164	0.038*
H81	0.4186	−0.0519	−0.0015	0.038*
C9	0.4554 (3)	0.2785 (3)	0.10960 (8)	0.0232 (4)
C10	0.2380 (3)	0.4133 (3)	0.18683 (8)	0.0272 (5)
C11	0.4430 (4)	0.5033 (4)	0.21226 (10)	0.0460 (7)
H113	0.5324	0.4193	0.2345	0.069*
H112	0.5333	0.5535	0.1818	0.069*
H111	0.397	0.5869	0.237	0.069*
C12	0.0968 (4)	0.5220 (3)	0.14804 (9)	0.0361 (6)
H123	0.1913	0.5667	0.1185	0.054*
H122	0.0237	0.6091	0.1718	0.054*
H121	−0.0235	0.4624	0.1285	0.054*
C13	0.0908 (4)	0.3347 (3)	0.23313 (10)	0.0478 (7)
H133	0.024	0.4304	0.2568	0.072*
H132	0.1835	0.2525	0.2576	0.072*
H131	−0.0379	0.2794	0.2154	0.072*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0318 (7)	0.0242 (10)	0.0346 (7)	0.0027 (6)	0.0115 (6)	−0.0015 (7)
C1	0.0300 (10)	0.0225 (13)	0.0337 (10)	−0.0030 (8)	0.0032 (8)	−0.0065 (10)
O2	0.0407 (8)	0.0269 (10)	0.0448 (8)	−0.0014 (7)	0.0130 (7)	0.0046 (8)
C2	0.0264 (9)	0.0356 (15)	0.0297 (9)	0.0059 (9)	0.0027 (8)	−0.0013 (11)
O3	0.0250 (7)	0.0445 (11)	0.0423 (8)	0.0087 (7)	0.0089 (6)	−0.0045 (8)
O4	0.0349 (7)	0.0313 (10)	0.0302 (6)	−0.0059 (6)	0.0085 (6)	0.0019 (7)
C4	0.0242 (9)	0.0277 (14)	0.0333 (9)	−0.0002 (8)	0.0025 (8)	−0.0074 (10)
C5	0.0246 (9)	0.0352 (14)	0.0233 (8)	0.0038 (10)	0.0065 (8)	0.0042 (10)
N6	0.0217 (8)	0.0253 (11)	0.0260 (7)	0.0027 (7)	0.0075 (6)	0.0013 (8)
C7	0.0214 (9)	0.0252 (13)	0.0253 (9)	−0.0015 (8)	−0.0024 (8)	−0.0022 (9)
C8	0.0248 (9)	0.0445 (17)	0.0261 (9)	0.0019 (9)	0.0004 (7)	−0.0077 (10)
C9	0.0179 (8)	0.0248 (13)	0.0268 (9)	0.0018 (8)	0.0006 (8)	0.0030 (9)
C10	0.0277 (9)	0.0240 (13)	0.0299 (9)	0.0053 (8)	0.0033 (7)	−0.0052 (10)
C11	0.0417 (13)	0.0521 (19)	0.0440 (12)	0.0031 (12)	−0.0057 (10)	−0.0136 (13)
C12	0.0359 (11)	0.0374 (15)	0.0350 (10)	0.0122 (10)	0.0014 (9)	−0.0004 (11)
C13	0.0544 (14)	0.0437 (18)	0.0452 (12)	0.0142 (12)	0.0215 (11)	0.0081 (12)

Geometric parameters (Å, º)

O1—C9	1.332 (2)	N6—C9	1.386 (3)
O1—C10	1.485 (3)	N6—C7	1.413 (3)
C1—C8	1.523 (3)	C8—H82	0.9865
C1—C7	1.530 (3)	C8—H81	0.9902
C1—C2	1.541 (3)	C10—C12	1.506 (3)
C1—H1	0.954	C10—C13	1.518 (3)
O2—C9	1.205 (2)	C10—C11	1.518 (3)
C2—O3	1.444 (2)	C11—H113	1.0007
C2—C4	1.446 (3)	C11—H112	0.973
C2—H2	0.9345	C11—H111	0.9287
O3—C4	1.435 (2)	C12—H123	0.9535
O4—C7	1.210 (2)	C12—H122	0.9929
C4—C5	1.534 (3)	C12—H121	0.9643
C4—H4	0.9134	C13—H133	1.0279
C5—N6	1.493 (2)	C13—H132	1.0287
C5—C8	1.517 (3)	C13—H131	0.9657
C5—H5	0.9708
C9—O1—C10	121.31 (16)	C5—C8—H82	108.7
C8—C1—C7	100.58 (16)	C1—C8—H82	113.2
C8—C1—C2	101.51 (15)	C5—C8—H81	111.6
C7—C1—C2	101.59 (16)	C1—C8—H81	113
C8—C1—H1	121.1	H82—C8—H81	114.3
C7—C1—H1	113.7	O2—C9—O1	127.08 (19)
C2—C1—H1	115.6	O2—C9—N6	122.34 (16)
O3—C2—C4	59.57 (13)	O1—C9—N6	110.56 (17)
O3—C2—C1	114.72 (15)	O1—C10—C12	109.58 (15)
C4—C2—C1	105.64 (17)	O1—C10—C13	101.19 (18)
O3—C2—H2	116.2	C12—C10—C13	111.35 (16)
C4—C2—H2	122.9	O1—C10—C11	110.09 (16)
C1—C2—H2	122.1	C12—C10—C11	112.57 (19)
C4—O3—C2	60.29 (13)	C13—C10—C11	111.48 (18)
O3—C4—C2	60.14 (13)	C10—C11—H113	106.6
O3—C4—C5	114.69 (16)	C10—C11—H112	109.8
C2—C4—C5	103.89 (17)	H113—C11—H112	112.4
O3—C4—H4	118.8	C10—C11—H111	111.5
C2—C4—H4	126.2	H113—C11—H111	108.8
C5—C4—H4	119.3	H112—C11—H111	107.8
N6—C5—C8	100.15 (15)	C10—C12—H123	110
N6—C5—C4	103.11 (13)	C10—C12—H122	108.2
C8—C5—C4	102.57 (18)	H123—C12—H122	112.4
N6—C5—H5	111	C10—C12—H121	112.9
C8—C5—H5	119.6	H123—C12—H121	105.4
C4—C5—H5	117.9	H122—C12—H121	107.9
C9—N6—C7	130.24 (14)	C10—C13—H133	106.3
C9—N6—C5	120.55 (16)	C10—C13—H132	111.7
C7—N6—C5	107.36 (15)	H133—C13—H132	112.8
O4—C7—N6	127.19 (18)	C10—C13—H131	109.1
O4—C7—C1	128.7 (2)	H133—C13—H131	106.6
N6—C7—C1	104.04 (15)	H132—C13—H131	110.2
C5—C8—C1	94.34 (14)
C8—C1—C2—O3	−30.5 (2)	C9—N6—C7—C1	−165.16 (18)
C7—C1—C2—O3	−133.92 (18)	C5—N6—C7—C1	−0.97 (17)
C8—C1—C2—C4	32.80 (19)	C8—C1—C7—O4	148.77 (18)
C7—C1—C2—C4	−70.68 (18)	C2—C1—C7—O4	−107.0 (2)
C1—C2—O3—C4	94.2 (2)	C8—C1—C7—N6	−33.49 (17)
C2—O3—C4—C5	−92.33 (18)	C2—C1—C7—N6	70.72 (17)
C1—C2—C4—O3	−109.83 (15)	N6—C5—C8—C1	−53.17 (15)
O3—C2—C4—C5	110.74 (15)	C4—C5—C8—C1	52.85 (15)
C1—C2—C4—C5	0.91 (19)	C7—C1—C8—C5	52.80 (16)
O3—C4—C5—N6	132.28 (17)	C2—C1—C8—C5	−51.47 (17)
C2—C4—C5—N6	69.07 (19)	C10—O1—C9—O2	0.3 (3)
O3—C4—C5—C8	28.6 (2)	C10—O1—C9—N6	−178.21 (14)
C2—C4—C5—C8	−34.65 (18)	C7—N6—C9—O2	166.88 (18)
C8—C5—N6—C9	−158.78 (16)	C5—N6—C9—O2	4.5 (3)
C4—C5—N6—C9	95.6 (2)	C7—N6—C9—O1	−14.5 (3)
C8—C5—N6—C7	35.19 (17)	C5—N6—C9—O1	−176.94 (14)
C4—C5—N6—C7	−70.39 (19)	C9—O1—C10—C12	63.1 (2)
C9—N6—C7—O4	12.6 (3)	C9—O1—C10—C13	−179.23 (16)
C5—N6—C7—O4	176.82 (16)	C9—O1—C10—C11	−61.2 (2)