tert-Butyl 3a-chloro­perhydro-2,6a-epoxy­oxireno[e]isoindole-5-carboxyl­ate

In the title compound, C₁₃H₁₈ClNO₄, the mol­ecules are linked only by weak van der Waals inter­actions. The boat form of the six-membered ring is almost symmetric with respect to the ep­oxy bridge. The three five-membered rings adopt envelope conformations.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.004 Å
• R factor = 0.043
• wR factor = 0.112
• Data-to-parameter ratio = 16.3

checkCIF/PLATON results

No syntax errors found



Alert level B
PLAT242_ALERT_2_B Check Low       Ueq as Compared to Neighbors for        C10

Alert level C
PLAT220_ALERT_2_C Large Non-Solvent    C     Ueq(max)/Ueq(min) ...       3.14 Ratio
PLAT222_ALERT_3_C Large Non-Solvent    H     Ueq(max)/Ueq(min) ...       3.63 Ratio
PLAT790_ALERT_4_C Centre of Gravity not Within Unit Cell: Resd.  #          1
              C13 H18 Cl N O4

Alert level G
PLAT199_ALERT_1_G Check the Reported _cell_measurement_temperature        293 K
PLAT200_ALERT_1_G Check the Reported _diffrn_ambient_temperature .        293 K
PLAT793_ALERT_1_G Check the Absolute Configuration of C1     = ...          S
PLAT793_ALERT_1_G Check the Absolute Configuration of C3     = ...          R
PLAT793_ALERT_1_G Check the Absolute Configuration of C4     = ...          S
PLAT793_ALERT_1_G Check the Absolute Configuration of C5     = ...          R
PLAT793_ALERT_1_G Check the Absolute Configuration of C6     = ...          R

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

   7 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   2 ALERT type 2 Indicator that the structure model may be wrong or deficient
   1 ALERT type 3 Indicator that the structure quality may be low
   1 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

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S1. Comment

Intramolecular Diels-Alder (IMDA) cycloadducts derived from hetero-atoms in tether of furans have recently been of great interest since they involve a ring formation for natural product synthesis such as Azadirachtin (Prajapati et al., 1993) and Fraquinocin E (Christoffers et al., 2005). The utility of an IMDA cycloadduct is another part of research concept in which usually the fragmentation of an oxa bridge in the cyclohexene part is required (Brickwood et al., 1999).

Figure 1 shows the molecular structure of the title compound. The pyrrolidine (N1/C7/C6/C1/C8), tetrahydrofuran (O1/C6—C3) and chloro-attached tetrahydrofuran (O1/C6/C1/C2/C3) rings adopt envelope conformations, and the total puckering parameter Q_T values are 0.331 (3), 0.525 (3) and 0.569 (3) A°, respectively (Cremer & Pople, 1975).

For a closely related compound, tert-Butyl 3a-chloro-2-methylperhydro-2,6a- epoxyoxireno[e]isoindole-5-carboxylate, see Koşar et al. (2007).

Related literature

For related literature, see: Brickwood et al. (1999); Christoffers & Baro (2005); Cremer & Pople (1975); Koşar et al. (2007); Prajapati et al. (1993).

S2. Experimental

To a solution of meta-chloroperbenzoic acid (m-CPBA) (120 mg, 0.66 mmol), which had previously been purified and re-crystallized from dry diethyl ether, in dichloromethane (10 ml), cooled to 273 K, was added dropwise a solution of tert-butyl 7a-chloro-1,6,7,7a-tetrahydro-3a,6-epoxyisoindole- 2-carboxylate (0.66 mmol) in dichloromethane (10 ml) over a period of 3 min. The reaction mixture was stirred at room temperature for 4 h and then diluted with cold 4% sodium bicarbonate solution (4 ml). The organic layer was separated, washed with water (20 ml) and concentrated in vacuo. The residue was subjected to flash column chromatography and yielded colourless crystals (110 mg, 56%). m.p: 410–412 K, t.l.c., (Hexane: Ethyl acetate (7:3)): Rf: 0.26.

S3. Refinement

The methyl H atoms were positioned geometrically and refined using a riding model with C—H = 0.96 Å, and U_iso=1.5 U_eq(C). Other H atoms were located in a difference map and refined freely.

Computing details

Data collection: X-AREA (Stoe & Cie, 2002); cell refinement: X-AREA; data reduction: X-RED (Stoe & Cie, 2002); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures

Fig. 1. The molecular structure of (I), with atom labels and 30% probability displacement ellipsoids for non-H atoms.

tert-Butyl 3a-chloroperhydro-2,6a-epoxyoxireno[e]isoindole-5-carboxylate

Crystal data

C13H18ClNO4	F(000) = 608
Mr = 287.73	Dx = 1.323 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 1048 reflections
a = 18.7133 (15) Å	θ = 2.2–27.9°
b = 8.3800 (8) Å	µ = 0.27 mm^−1
c = 9.2123 (7) Å	T = 293 K
β = 90.134 (7)°	Plate, colourless
V = 1444.6 (2) Å^3	0.50 × 0.32 × 0.03 mm
Z = 4

Data collection

Stoe IPDSII diffractometer	3390 independent reflections
Radiation source: fine-focus sealed tube	1847 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.045
Detector resolution: 6.67 pixels mm^-1	θmax = 27.9°, θmin = 2.2°
ω scans	h = −24→24
Absorption correction: integration (X-RED; Stoe & Cie, 2002)	k = −10→10
Tmin = 0.911, Tmax = 0.992	l = −11→11
11238 measured reflections

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.043	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.112	H atoms treated by a mixture of independent and constrained refinement
S = 0.88	w = 1/[σ^2(Fo^2) + (0.1002P)^2] where P = (Fo^2 + 2Fc^2)/3
3390 reflections	(Δ/σ)max = 0.001
208 parameters	Δρmax = 0.16 e Å^−3
0 restraints	Δρmin = −0.17 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.

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 (Ų)

	x	y	z	Uiso*/Ueq
H7B	0.8797 (12)	−0.369 (3)	0.287 (2)	0.051 (6)*
H2B	0.8158 (14)	0.132 (3)	0.432 (3)	0.069 (8)*
H5	0.9326 (13)	−0.042 (3)	0.043 (3)	0.063 (7)*
H8B	0.7149 (14)	−0.099 (3)	0.293 (3)	0.057 (6)*
H7A	0.8627 (12)	−0.324 (3)	0.120 (3)	0.051 (6)*
H4	0.9735 (13)	0.188 (3)	0.195 (3)	0.061 (7)*
H8A	0.7649 (12)	−0.123 (3)	0.423 (3)	0.059 (7)*
H2A	0.8411 (12)	0.225 (3)	0.290 (3)	0.062 (7)*
H3	0.9437 (14)	0.108 (3)	0.459 (3)	0.071 (8)*
Cl1	0.78679 (4)	0.04055 (8)	0.07373 (8)	0.0707 (2)
O3	0.75689 (9)	−0.53162 (17)	0.1873 (2)	0.0633 (5)
O1	0.91221 (8)	−0.09924 (16)	0.38532 (16)	0.0494 (4)
N1	0.78055 (9)	−0.28137 (18)	0.2605 (2)	0.0446 (4)
O2	1.00890 (8)	−0.04342 (19)	0.2061 (2)	0.0653 (5)
C9	0.73723 (11)	−0.4063 (2)	0.2387 (2)	0.0462 (5)
C1	0.81622 (11)	−0.0154 (2)	0.2528 (2)	0.0438 (5)
O4	0.67030 (8)	−0.37214 (19)	0.28057 (19)	0.0612 (4)
C7	0.85606 (11)	−0.2919 (2)	0.2225 (3)	0.0443 (5)
C3	0.92012 (13)	0.0720 (3)	0.3739 (3)	0.0581 (6)
C5	0.93750 (12)	−0.0444 (3)	0.1468 (3)	0.0510 (5)
C6	0.88277 (10)	−0.1245 (2)	0.2436 (2)	0.0392 (4)
C8	0.76129 (13)	−0.1262 (3)	0.3189 (3)	0.0490 (5)
C10	0.61231 (13)	−0.4860 (3)	0.2554 (3)	0.0697 (7)
C2	0.84309 (14)	0.1263 (3)	0.3439 (3)	0.0589 (6)
C4	0.96174 (13)	0.0886 (3)	0.2346 (3)	0.0604 (7)
C13	0.54841 (16)	−0.3970 (5)	0.3134 (5)	0.1233 (15)
H13A	0.5409	−0.3020	0.2570	0.185*
H13B	0.5568	−0.3684	0.4129	0.185*
H13C	0.5068	−0.4637	0.3071	0.185*
C12	0.62559 (18)	−0.6360 (4)	0.3405 (5)	0.1143 (14)
H12A	0.6664	−0.6905	0.3015	0.171*
H12B	0.5844	−0.7040	0.3342	0.171*
H12C	0.6345	−0.6094	0.4403	0.171*
C11	0.60394 (19)	−0.5166 (5)	0.0956 (4)	0.1048 (12)
H11A	0.6448	−0.5742	0.0606	0.157*
H11B	0.6002	−0.4167	0.0451	0.157*
H11C	0.5615	−0.5784	0.0789	0.157*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Cl1	0.0830 (5)	0.0629 (4)	0.0661 (4)	0.0032 (3)	−0.0240 (3)	0.0150 (3)
O3	0.0566 (9)	0.0427 (8)	0.0907 (13)	−0.0066 (7)	0.0049 (9)	−0.0068 (8)
O1	0.0569 (9)	0.0499 (8)	0.0413 (9)	−0.0035 (7)	−0.0076 (7)	0.0012 (7)
N1	0.0385 (9)	0.0375 (9)	0.0577 (12)	−0.0029 (7)	0.0077 (8)	−0.0018 (8)
O2	0.0477 (9)	0.0570 (9)	0.0914 (14)	−0.0100 (7)	0.0072 (9)	0.0031 (9)
C9	0.0430 (12)	0.0449 (11)	0.0507 (14)	−0.0051 (9)	−0.0008 (9)	0.0059 (10)
C1	0.0473 (11)	0.0397 (10)	0.0444 (12)	0.0016 (8)	−0.0030 (9)	−0.0036 (9)
O4	0.0399 (8)	0.0628 (10)	0.0811 (13)	−0.0099 (7)	0.0080 (8)	−0.0060 (9)
C7	0.0409 (11)	0.0390 (10)	0.0531 (15)	−0.0017 (9)	0.0063 (10)	−0.0037 (10)
C3	0.0672 (16)	0.0457 (12)	0.0613 (17)	−0.0072 (10)	−0.0137 (12)	−0.0120 (11)
C5	0.0491 (13)	0.0518 (12)	0.0521 (15)	−0.0077 (10)	0.0061 (10)	0.0051 (11)
C6	0.0434 (11)	0.0384 (10)	0.0357 (12)	−0.0026 (8)	0.0008 (8)	0.0003 (8)
C8	0.0439 (13)	0.0470 (12)	0.0562 (17)	0.0017 (9)	0.0062 (11)	−0.0077 (11)
C10	0.0452 (13)	0.0734 (16)	0.090 (2)	−0.0162 (12)	−0.0038 (13)	0.0052 (14)
C2	0.0667 (16)	0.0422 (13)	0.0680 (19)	0.0003 (11)	0.0000 (13)	−0.0143 (12)
C4	0.0563 (14)	0.0439 (12)	0.0811 (19)	−0.0134 (11)	−0.0030 (13)	0.0080 (12)
C13	0.0484 (18)	0.130 (3)	0.192 (5)	−0.0154 (18)	0.020 (2)	−0.023 (3)
C12	0.081 (2)	0.110 (3)	0.152 (4)	−0.0485 (19)	−0.022 (2)	0.058 (2)
C11	0.085 (2)	0.131 (3)	0.098 (3)	−0.030 (2)	−0.0279 (19)	−0.002 (2)

Geometric parameters (Å, º)

Cl1—C1	1.800 (2)	C5—C4	1.450 (3)
O3—C9	1.210 (3)	C5—C6	1.516 (3)
O1—C6	1.432 (2)	C5—H5	0.96 (3)
O1—C3	1.446 (3)	C8—H8B	0.93 (2)
N1—C9	1.339 (3)	C8—H8A	0.96 (3)
N1—C8	1.453 (3)	C10—C12	1.502 (4)
N1—C7	1.459 (3)	C10—C11	1.502 (4)
O2—C4	1.440 (3)	C10—C13	1.508 (4)
O2—C5	1.442 (3)	C2—H2B	0.96 (3)
C9—O4	1.342 (3)	C2—H2A	0.96 (3)
C1—C8	1.514 (3)	C4—H4	0.93 (2)
C1—C2	1.538 (3)	C13—H13A	0.9600
C1—C6	1.548 (3)	C13—H13B	0.9600
O4—C10	1.463 (3)	C13—H13C	0.9600
C7—C6	1.501 (3)	C12—H12A	0.9600
C7—H7B	0.98 (2)	C12—H12B	0.9600
C7—H7A	0.99 (3)	C12—H12C	0.9600
C3—C4	1.509 (4)	C11—H11A	0.9600
C3—C2	1.536 (4)	C11—H11B	0.9600
C3—H3	0.95 (3)	C11—H11C	0.9600
C6—O1—C3	96.88 (15)	C1—C8—H8B	112.2 (15)
C9—N1—C8	127.19 (17)	N1—C8—H8A	112.0 (14)
C9—N1—C7	120.21 (17)	C1—C8—H8A	109.9 (14)
C8—N1—C7	112.59 (16)	H8B—C8—H8A	108 (2)
C4—O2—C5	60.40 (15)	O4—C10—C12	110.0 (2)
O3—C9—N1	123.6 (2)	O4—C10—C11	110.0 (2)
O3—C9—O4	125.62 (19)	C12—C10—C11	112.7 (3)
N1—C9—O4	110.82 (18)	O4—C10—C13	102.1 (2)
C8—C1—C2	118.4 (2)	C12—C10—C13	111.1 (3)
C8—C1—C6	101.95 (16)	C11—C10—C13	110.5 (3)
C2—C1—C6	102.96 (17)	C3—C2—C1	100.05 (18)
C8—C1—Cl1	108.77 (16)	C3—C2—H2B	111.4 (16)
C2—C1—Cl1	113.45 (17)	C1—C2—H2B	109.0 (16)
C6—C1—Cl1	110.36 (14)	C3—C2—H2A	112.4 (14)
C9—O4—C10	120.50 (18)	C1—C2—H2A	111.5 (15)
N1—C7—C6	103.57 (16)	H2B—C2—H2A	112 (2)
N1—C7—H7B	109.3 (13)	O2—C4—C5	59.88 (15)
C6—C7—H7B	112.7 (13)	O2—C4—C3	113.7 (2)
N1—C7—H7A	111.6 (13)	C5—C4—C3	104.00 (19)
C6—C7—H7A	109.4 (13)	O2—C4—H4	118.0 (15)
H7B—C7—H7A	110.1 (19)	C5—C4—H4	122.9 (15)
O1—C3—C4	101.94 (19)	C3—C4—H4	122.2 (15)
O1—C3—C2	102.19 (18)	C10—C13—H13A	109.5
C4—C3—C2	107.8 (2)	C10—C13—H13B	109.5
O1—C3—H3	107.8 (16)	H13A—C13—H13B	109.5
C4—C3—H3	115.5 (16)	C10—C13—H13C	109.5
C2—C3—H3	119.3 (16)	H13A—C13—H13C	109.5
O2—C5—C4	59.71 (15)	H13B—C13—H13C	109.5
O2—C5—C6	114.0 (2)	C10—C12—H12A	109.5
C4—C5—C6	102.9 (2)	C10—C12—H12B	109.5
O2—C5—H5	117.6 (15)	H12A—C12—H12B	109.5
C4—C5—H5	124.9 (15)	C10—C12—H12C	109.5
C6—C5—H5	122.0 (14)	H12A—C12—H12C	109.5
O1—C6—C7	112.54 (17)	H12B—C12—H12C	109.5
O1—C6—C5	102.24 (16)	C10—C11—H11A	109.5
C7—C6—C5	124.24 (19)	C10—C11—H11B	109.5
O1—C6—C1	99.80 (15)	H11A—C11—H11B	109.5
C7—C6—C1	106.95 (16)	C10—C11—H11C	109.5
C5—C6—C1	108.39 (16)	H11A—C11—H11C	109.5
N1—C8—C1	103.32 (17)	H11B—C11—H11C	109.5
N1—C8—H8B	111.1 (14)
C8—N1—C9—O3	178.8 (2)	C2—C1—C6—C7	153.6 (2)
C7—N1—C9—O3	−0.4 (3)	Cl1—C1—C6—C7	−85.05 (19)
C8—N1—C9—O4	−0.8 (3)	C8—C1—C6—C5	166.53 (18)
C7—N1—C9—O4	179.98 (19)	C2—C1—C6—C5	−70.3 (2)
O3—C9—O4—C10	−4.9 (4)	Cl1—C1—C6—C5	51.11 (19)
N1—C9—O4—C10	174.7 (2)	C9—N1—C8—C1	−153.1 (2)
C9—N1—C7—C6	172.53 (19)	C7—N1—C8—C1	26.1 (3)
C8—N1—C7—C6	−6.8 (3)	C2—C1—C8—N1	−145.2 (2)
C6—O1—C3—C4	−52.72 (19)	C6—C1—C8—N1	−33.1 (2)
C6—O1—C3—C2	58.7 (2)	Cl1—C1—C8—N1	83.45 (19)
C4—O2—C5—C6	−91.3 (2)	C9—O4—C10—C12	64.0 (3)
C3—O1—C6—C7	−170.96 (18)	C9—O4—C10—C11	−60.7 (3)
C3—O1—C6—C5	53.53 (19)	C9—O4—C10—C13	−178.0 (3)
C3—O1—C6—C1	−57.89 (17)	O1—C3—C2—C1	−34.1 (3)
N1—C7—C6—O1	93.4 (2)	C4—C3—C2—C1	72.8 (2)
N1—C7—C6—C5	−142.5 (2)	C8—C1—C2—C3	110.3 (2)
N1—C7—C6—C1	−15.2 (2)	C6—C1—C2—C3	−1.2 (2)
O2—C5—C6—O1	28.3 (2)	Cl1—C1—C2—C3	−120.42 (19)
C4—C5—C6—O1	−34.1 (2)	C5—O2—C4—C3	92.9 (2)
O2—C5—C6—C7	−100.2 (2)	C6—C5—C4—O2	110.41 (19)
C4—C5—C6—C7	−162.5 (2)	O2—C5—C4—C3	−109.5 (2)
O2—C5—C6—C1	133.09 (19)	C6—C5—C4—C3	0.9 (2)
C4—C5—C6—C1	70.8 (2)	O1—C3—C4—O2	−30.8 (2)
C8—C1—C6—O1	−86.96 (18)	C2—C3—C4—O2	−137.96 (19)
C2—C1—C6—O1	36.2 (2)	O1—C3—C4—C5	32.1 (2)
Cl1—C1—C6—O1	157.62 (12)	C2—C3—C4—C5	−75.0 (2)
C8—C1—C6—C7	30.4 (2)