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Acta Crystallogr Sect E Struct Rep Online. 2008 June 1; 64(Pt 6): o1149.
Published online 2008 May 24. doi:  10.1107/S1600536808014876
PMCID: PMC2961559

Di-tert-butyl N,N′-(octa­hydro­penta­lene-2,5-di­yl)dicarbamate

Abstract

In the molecule of the title compound, C18H32N2O4, the central bicyclo­[3.3.0]octane (octa­hydro­penta­lene) has a rigid ring junction. Both rings of the bicyclo­[3.3.0]octane unit adopt an envelope conformation, and the flexible tert-butyl­carbamoyl side chains each have an extended conformation. Such a constrained bicyclo­[3.3.0]octane aliphatic template is of inter­est with respect to the design of novel self-assembling motifs. Mol­ecules related by c-glide symmetry are linked via inter­molecular N—H(...)O hydrogen bonds, forming a two-dimensional layer structure. Neighboring layers are weakly associated along the a axis due to the close approach of the tert-butyl­carbamoyl groups (2.55 Å).

Related literature

For related literature, see: Bertz et al. (1982 [triangle]); Kendhale et al. (2008 [triangle]); Yates et al. (1960 [triangle]); Yeo et al. (2006 [triangle]).

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Object name is e-64-o1149-scheme1.jpg

Experimental

Crystal data

  • C18H32N2O4
  • M r = 340.46
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-64-o1149-efi1.jpg
  • a = 33.161 (17) Å
  • b = 6.060 (3) Å
  • c = 9.926 (5) Å
  • β = 95.594 (9)°
  • V = 1985.2 (18) Å3
  • Z = 4
  • Mo Kα radiation
  • μ = 0.08 mm−1
  • T = 297 (2) K
  • 0.64 × 0.13 × 0.08 mm

Data collection

  • Bruker SMART APEX diffractometer
  • Absorption correction: multi-scan (SADABS; Bruker, 2003 [triangle]) T min = 0.951, T max = 0.994
  • 9395 measured reflections
  • 3479 independent reflections
  • 2863 reflections with I > 2σ(I)
  • R int = 0.026

Refinement

  • R[F 2 > 2σ(F 2)] = 0.056
  • wR(F 2) = 0.133
  • S = 1.08
  • 3479 reflections
  • 271 parameters
  • H atoms treated by a mixture of independent and constrained refinement
  • Δρmax = 0.17 e Å−3
  • Δρmin = −0.14 e Å−3

Data collection: SMART (Bruker, 2003 [triangle]); cell refinement: SAINT (Bruker, 2003 [triangle]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: ORTEP-3 (Farrugia, 1997 [triangle]); software used to prepare material for publication: SHELXTL (Sheldrick, 2008 [triangle]).

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536808014876/wk2086sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536808014876/wk2086Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Acknowledgments

AMK is the recipient of a Senior Research Fellowship from the Council of Scientific and Industrial Research (CSIR), New Delhi, India.

supplementary crystallographic information

Comment

The skeleton of bicyclo[3.3.0]octane is interesting because it has a rigid ring junction as well as conformationally flexible side groups (Bertz et al., 1982; Yates et al., 1960). Depending on the substituents, it can adopt one of three different conformations in a given circumstance (Yeo et al., 2006). In the context of our interest in extending the applicability of bicyclo[3.3.0]octane as a self-assembling motif (Kendhale et al., 2008), the title compound (I) has been synthesized and here we report its crystal structure.

The two five-membered rings of the bicyclo[3.3.0]octane subunit adopt an exo/endo envelope conformation, while the flexible tert-Butylcarbamoyl group takes an extended conformation (Fig. 1).

In the crystal, molecules related by c-glide symmetry are linked via intermolecular N—H···O hydrogen bonds (Table 1) forming a layered arrangement (Fig.2). These layers are weakly associated along the a axis due to the close approach of the bulkier tert-butylcarbamoy group (2.55 Å).

Experimental

Tetramethylbicyclo[3.3.0]octane-3,7-dione-2,4,6,8-tetracarboxylate, bicyclo[3.3.0]octane-3,7-dione and 2, 5-dihydroxy-bicyclo[3.3.0]octane were prepared according to the literature procedure (Bertz et al., 1982; Yeo et al., 2006). The 2, 5-dihydroxy-bicyclo[3.3.0]octane (3.86 g, 27.183 mmol) was treated with methanesulfonyl chloride (6.31 ml, 9.34 g, 81.549 mmol) and triethyl amine (11.36 ml, 8.25 g, 81.549 mmol) in DCM (50 ml) at room temperature for 12 h to obtain 2,5-dimethanesulfonyloxy bicyclo[3.3.0]octane. Nucleophilic displacement of 2,5-dimethanesulfonyloxy bicyclo[3.3.0]octane (6 g, 20.134 mmol) by sodium azide (13.08 g, 201.34 mmol) in DMF (40 ml) at 343 K for 24 h, delivered 2,5-diazido-bicyclo[3.3.0]octane. The 2,5-diazido-bicyclo[3.3.0]octane (0.5 g, 2.6041 mmol) was hydrogenated in the presence of Pd/c-methanol (20 ml) system, and in situ protection with tert-Butyl Dicarbonate (Boc)2O, (1.7 g, 7.812 mmol), afforded the required 5-tert-Butoxycarbonylamino-octahydro-pentalen-2-yl)-carbamic acid tert-butyl ester (0.61 g, 69%). Colourless needles suitable for X-ray diffraction were obtained by slow evaporation of a solution in methanol-ethyl acetate (1:4) mixture at room temperature.

Refinement

The H atoms bonded to bicyclo[3.3.0]octane unit were located in a difference Fourier map and refined isotropically. Other H atoms bonded to N atoms and tert-butyl group were placed in geometrically idealized positions with N—H = 0.86 Å (for NH) and C—H = 0.96 Å (for methyl H) and constrained to ride on their parent atoms with Uiso(H) = xUeq(C,N), where x = 1.2 for NH amd x = 1.5 for methyl H.

Figures

Fig. 1.
Molecular structure of (I), with atom labels and 50% probability displacement ellipsoids for non-H atoms.
Fig. 2.
Molecular packing viewed down the b axis, showing the layered arrangement of the molecules linked via N—H···O hydrogen bonds.

Crystal data

C18H32N2O4F000 = 744
Mr = 340.46Dx = 1.139 Mg m3
Monoclinic, P2/cMo Kα radiation λ = 0.71073 Å
Hall symbol: -P 2ycCell parameters from 3113 reflections
a = 33.161 (17) Åθ = 2.5–25.4º
b = 6.060 (3) ŵ = 0.08 mm1
c = 9.926 (5) ÅT = 297 (2) K
β = 95.594 (9)ºNeedle, colourless
V = 1985.2 (18) Å30.64 × 0.13 × 0.08 mm
Z = 4

Data collection

Bruker SMART APEX diffractometer3479 independent reflections
Radiation source: fine-focus sealed tube2863 reflections with I > 2σ(I)
Monochromator: graphiteRint = 0.026
T = 297(2) Kθmax = 25.0º
[var phi] and ω scansθmin = 1.2º
Absorption correction: multi-scan(SADABS; Bruker, 2003)h = −39→29
Tmin = 0.951, Tmax = 0.994k = −7→7
9395 measured reflectionsl = −10→11

Refinement

Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: geom, difmap for bicyclo unit
R[F2 > 2σ(F2)] = 0.056H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.133  w = 1/[σ2(Fo2) + (0.0452P)2 + 0.984P] where P = (Fo2 + 2Fc2)/3
S = 1.08(Δ/σ)max < 0.001
3479 reflectionsΔρmax = 0.17 e Å3
271 parametersΔρmin = −0.14 e Å3
Primary atom site location: structure-invariant direct methodsExtinction correction: none

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 (Å2)

xyzUiso*/Ueq
O10.14804 (5)1.1114 (3)0.46136 (15)0.0640 (5)
O20.10387 (4)1.1306 (3)0.62262 (15)0.0567 (4)
O30.35645 (5)0.4521 (3)0.36953 (14)0.0614 (5)
O40.39622 (4)0.3724 (3)0.56279 (14)0.0559 (4)
N10.16176 (5)0.9541 (3)0.66747 (17)0.0496 (5)
H10.15250.92740.74380.060*
N20.34243 (5)0.5850 (3)0.57189 (16)0.0460 (5)
H20.34960.58920.65750.055*
C10.20180 (6)0.8722 (4)0.6444 (2)0.0421 (5)
C20.23645 (7)0.9724 (4)0.7371 (3)0.0526 (6)
C30.27303 (6)0.8282 (3)0.7141 (2)0.0395 (5)
C40.25453 (6)0.6036 (3)0.6631 (2)0.0396 (5)
C50.20867 (7)0.6266 (4)0.6674 (3)0.0485 (5)
C60.29869 (7)0.9084 (4)0.6030 (2)0.0471 (5)
C70.30653 (6)0.7070 (4)0.5165 (2)0.0439 (5)
C80.26760 (7)0.5747 (4)0.5201 (2)0.0437 (5)
C90.13895 (6)1.0694 (4)0.5737 (2)0.0450 (5)
C100.07445 (7)1.2714 (4)0.5428 (2)0.0522 (6)
C110.05791 (8)1.1566 (5)0.4146 (3)0.0763 (8)
H11A0.07881.14490.35450.114*
H11B0.03561.23990.37160.114*
H11C0.04871.01160.43600.114*
C120.04103 (8)1.2937 (6)0.6378 (3)0.0875 (10)
H12A0.03021.15050.65470.131*
H12B0.01981.38640.59650.131*
H12C0.05211.35820.72180.131*
C130.09321 (10)1.4901 (5)0.5166 (4)0.0927 (10)
H13A0.10681.54630.59940.139*
H13B0.07251.59170.48250.139*
H13C0.11241.47240.45110.139*
C140.36414 (6)0.4672 (4)0.4910 (2)0.0415 (5)
C150.42463 (7)0.2332 (4)0.4955 (2)0.0554 (6)
C160.45595 (10)0.1763 (7)0.6134 (3)0.1111 (14)
H16A0.46670.30980.65470.167*
H16B0.47750.09250.58060.167*
H16C0.44330.09080.67910.167*
C170.40278 (10)0.0335 (5)0.4356 (4)0.0995 (12)
H17A0.3882−0.03600.50300.149*
H17B0.4221−0.06860.40510.149*
H17C0.38410.07750.36040.149*
C180.44483 (8)0.3633 (5)0.3914 (3)0.0732 (8)
H18A0.42550.39420.31530.110*
H18B0.46680.27900.36180.110*
H18C0.45500.49940.43060.110*
H30.2897 (6)0.808 (3)0.798 (2)0.043 (6)*
H40.2652 (6)0.486 (4)0.720 (2)0.050 (6)*
H70.3117 (6)0.747 (3)0.422 (2)0.047 (6)*
H1A0.2045 (6)0.908 (3)0.555 (2)0.045 (6)*
H2A0.2412 (8)1.128 (5)0.717 (3)0.074 (8)*
H5A0.1936 (8)0.540 (5)0.598 (3)0.080 (9)*
H6A0.3249 (8)0.982 (4)0.643 (3)0.070 (7)*
H8A0.2709 (6)0.416 (4)0.495 (2)0.044 (6)*
H2B0.2287 (8)0.959 (4)0.836 (3)0.073 (8)*
H5B0.2002 (7)0.592 (4)0.758 (2)0.052 (6)*
H6B0.2824 (7)1.009 (4)0.544 (2)0.058 (7)*
H8B0.2473 (6)0.636 (3)0.456 (2)0.038 (5)*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
O10.0590 (10)0.0951 (14)0.0394 (9)0.0194 (9)0.0125 (7)0.0133 (9)
O20.0453 (9)0.0790 (12)0.0467 (9)0.0222 (8)0.0095 (7)0.0101 (8)
O30.0549 (10)0.0956 (13)0.0333 (9)0.0147 (9)0.0019 (7)−0.0137 (8)
O40.0495 (9)0.0773 (11)0.0413 (8)0.0235 (8)0.0055 (7)−0.0050 (8)
N10.0437 (10)0.0693 (13)0.0377 (9)0.0157 (9)0.0131 (8)0.0096 (9)
N20.0442 (10)0.0644 (12)0.0296 (8)0.0127 (9)0.0051 (7)−0.0014 (8)
C10.0410 (11)0.0513 (13)0.0353 (11)0.0063 (10)0.0095 (9)0.0038 (10)
C20.0498 (13)0.0465 (14)0.0628 (15)−0.0001 (11)0.0122 (11)−0.0151 (12)
C30.0394 (11)0.0432 (12)0.0356 (11)−0.0004 (9)0.0022 (9)−0.0018 (9)
C40.0439 (12)0.0335 (11)0.0415 (11)0.0030 (9)0.0049 (9)0.0040 (9)
C50.0428 (12)0.0478 (13)0.0559 (14)−0.0051 (10)0.0092 (11)−0.0022 (11)
C60.0429 (12)0.0424 (12)0.0569 (14)0.0003 (10)0.0093 (10)0.0061 (11)
C70.0412 (11)0.0570 (14)0.0341 (11)0.0087 (10)0.0072 (9)0.0072 (10)
C80.0448 (12)0.0450 (13)0.0406 (12)0.0084 (10)0.0001 (9)−0.0078 (10)
C90.0416 (12)0.0544 (13)0.0395 (12)0.0069 (10)0.0058 (9)−0.0011 (10)
C100.0436 (12)0.0594 (14)0.0523 (13)0.0136 (11)−0.0024 (10)0.0019 (11)
C110.0626 (16)0.089 (2)0.0735 (18)0.0099 (15)−0.0139 (14)−0.0117 (16)
C120.0612 (17)0.122 (3)0.0797 (19)0.0425 (18)0.0100 (14)0.0030 (19)
C130.079 (2)0.0664 (19)0.128 (3)0.0028 (16)−0.0131 (19)0.0090 (19)
C140.0361 (11)0.0540 (13)0.0348 (11)0.0010 (10)0.0044 (8)−0.0033 (9)
C150.0534 (14)0.0604 (15)0.0551 (13)0.0157 (12)0.0195 (11)0.0013 (12)
C160.096 (2)0.159 (4)0.081 (2)0.084 (2)0.0219 (18)0.025 (2)
C170.104 (2)0.0595 (18)0.145 (3)−0.0050 (17)0.063 (2)−0.018 (2)
C180.0549 (15)0.0820 (19)0.0867 (19)0.0037 (14)0.0270 (14)0.0087 (16)

Geometric parameters (Å, °)

O1—C91.210 (3)C7—C81.523 (3)
O2—C91.355 (2)C7—H71.00 (2)
O2—C101.469 (3)C8—H8A1.00 (2)
O3—C141.211 (2)C8—H8B0.95 (2)
O4—C141.350 (2)C10—C131.497 (4)
O4—C151.472 (3)C10—C111.506 (3)
N1—C91.337 (3)C10—C121.530 (3)
N1—C11.456 (3)C11—H11A0.9600
N1—H10.8600C11—H11B0.9600
N2—C141.336 (3)C11—H11C0.9600
N2—C71.462 (3)C12—H12A0.9600
N2—H20.8600C12—H12B0.9600
C1—C51.520 (3)C12—H12C0.9600
C1—C21.526 (3)C13—H13A0.9600
C1—H1A0.92 (2)C13—H13B0.9600
C2—C31.530 (3)C13—H13C0.9600
C2—H2A0.98 (3)C15—C171.503 (4)
C2—H2B1.04 (3)C15—C181.508 (3)
C3—C61.536 (3)C15—C161.527 (4)
C3—C41.557 (3)C16—H16A0.9600
C3—H30.96 (2)C16—H16B0.9600
C4—C51.532 (3)C16—H16C0.9600
C4—C81.534 (3)C17—H17A0.9600
C4—H40.96 (2)C17—H17B0.9600
C5—H5A0.96 (3)C17—H17C0.9600
C5—H5B0.99 (2)C18—H18A0.9600
C6—C71.529 (3)C18—H18B0.9600
C6—H6A1.02 (3)C18—H18C0.9600
C6—H6B0.97 (2)
C9—O2—C10120.93 (17)H8A—C8—H8B107.1 (17)
C14—O4—C15120.70 (16)O1—C9—N1125.17 (19)
C9—N1—C1122.09 (17)O1—C9—O2124.89 (19)
C9—N1—H1119.0N1—C9—O2109.93 (18)
C1—N1—H1119.0O2—C10—C13110.0 (2)
C14—N2—C7120.73 (17)O2—C10—C11110.8 (2)
C14—N2—H2119.6C13—C10—C11112.7 (2)
C7—N2—H2119.6O2—C10—C12101.63 (18)
N1—C1—C5115.83 (18)C13—C10—C12111.5 (2)
N1—C1—C2114.47 (18)C11—C10—C12109.6 (2)
C5—C1—C2101.90 (19)C10—C11—H11A109.5
N1—C1—H1A104.2 (13)C10—C11—H11B109.5
C5—C1—H1A110.1 (13)H11A—C11—H11B109.5
C2—C1—H1A110.4 (13)C10—C11—H11C109.5
C1—C2—C3104.11 (18)H11A—C11—H11C109.5
C1—C2—H2A112.7 (16)H11B—C11—H11C109.5
C3—C2—H2A111.8 (16)C10—C12—H12A109.5
C1—C2—H2B107.3 (14)C10—C12—H12B109.5
C3—C2—H2B111.8 (14)H12A—C12—H12B109.5
H2A—C2—H2B109 (2)C10—C12—H12C109.5
C2—C3—C6115.44 (19)H12A—C12—H12C109.5
C2—C3—C4104.78 (17)H12B—C12—H12C109.5
C6—C3—C4105.77 (17)C10—C13—H13A109.5
C2—C3—H3110.0 (12)C10—C13—H13B109.5
C6—C3—H3110.2 (12)H13A—C13—H13B109.5
C4—C3—H3110.3 (13)C10—C13—H13C109.5
C5—C4—C8113.99 (19)H13A—C13—H13C109.5
C5—C4—C3105.79 (17)H13B—C13—H13C109.5
C8—C4—C3105.21 (17)O3—C14—N2124.39 (19)
C5—C4—H4111.3 (13)O3—C14—O4124.89 (19)
C8—C4—H4109.9 (13)N2—C14—O4110.70 (17)
C3—C4—H4110.4 (13)O4—C15—C17109.6 (2)
C1—C5—C4102.69 (17)O4—C15—C18111.0 (2)
C1—C5—H5A111.6 (17)C17—C15—C18112.3 (2)
C4—C5—H5A112.2 (16)O4—C15—C16101.48 (19)
C1—C5—H5B106.9 (13)C17—C15—C16112.8 (3)
C4—C5—H5B112.0 (13)C18—C15—C16109.2 (2)
H5A—C5—H5B111 (2)C15—C16—H16A109.5
C7—C6—C3106.68 (18)C15—C16—H16B109.5
C7—C6—H6A112.4 (14)H16A—C16—H16B109.5
C3—C6—H6A111.9 (14)C15—C16—H16C109.5
C7—C6—H6B105.8 (14)H16A—C16—H16C109.5
C3—C6—H6B108.6 (14)H16B—C16—H16C109.5
H6A—C6—H6B111 (2)C15—C17—H17A109.5
N2—C7—C8112.69 (19)C15—C17—H17B109.5
N2—C7—C6111.67 (18)H17A—C17—H17B109.5
C8—C7—C6102.47 (17)C15—C17—H17C109.5
N2—C7—H7105.5 (12)H17A—C17—H17C109.5
C8—C7—H7111.8 (12)H17B—C17—H17C109.5
C6—C7—H7112.9 (12)C15—C18—H18A109.5
C7—C8—C4106.16 (17)C15—C18—H18B109.5
C7—C8—H8A112.7 (12)H18A—C18—H18B109.5
C4—C8—H8A112.7 (12)C15—C18—H18C109.5
C7—C8—H8B109.0 (12)H18A—C18—H18C109.5
C4—C8—H8B109.2 (12)H18B—C18—H18C109.5
C9—N1—C1—C5−126.3 (2)C3—C6—C7—C834.0 (2)
C9—N1—C1—C2115.6 (2)N2—C7—C8—C483.2 (2)
N1—C1—C2—C3168.58 (18)C6—C7—C8—C4−36.9 (2)
C5—C1—C2—C342.8 (2)C5—C4—C8—C7141.38 (19)
C1—C2—C3—C691.7 (2)C3—C4—C8—C725.9 (2)
C1—C2—C3—C4−24.2 (2)C1—N1—C9—O12.5 (4)
C2—C3—C4—C5−3.1 (2)C1—N1—C9—O2−178.18 (19)
C6—C3—C4—C5−125.53 (19)C10—O2—C9—O1−4.6 (4)
C2—C3—C4—C8117.87 (19)C10—O2—C9—N1176.08 (19)
C6—C3—C4—C8−4.6 (2)C9—O2—C10—C13−61.7 (3)
N1—C1—C5—C4−169.18 (18)C9—O2—C10—C1163.6 (3)
C2—C1—C5—C4−44.3 (2)C9—O2—C10—C12180.0 (2)
C8—C4—C5—C1−85.8 (2)C7—N2—C14—O30.3 (3)
C3—C4—C5—C129.3 (2)C7—N2—C14—O4178.76 (18)
C2—C3—C6—C7−133.66 (19)C15—O4—C14—O3−1.7 (3)
C4—C3—C6—C7−18.3 (2)C15—O4—C14—N2179.80 (19)
C14—N2—C7—C893.1 (2)C14—O4—C15—C17−63.5 (3)
C14—N2—C7—C6−152.15 (19)C14—O4—C15—C1861.1 (3)
C3—C6—C7—N2−86.9 (2)C14—O4—C15—C16177.1 (2)

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
N2—H2···O3i0.862.112.954 (3)167
N1—H1···O1ii0.862.193.022 (3)162

Symmetry codes: (i) x, −y+1, z+1/2; (ii) x, −y+2, z+1/2.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: WK2086).

References

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