organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

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ISSN: 2056-9890

(1R*,3S*,8S*)-2,2-Di­fluoro-3,8-dihydr­­oxy-5,5-di­methyl­cyclo­oct-4(Z)-en-1-yl N,N-di­ethyl­carbamate

CROSSMARK_Color_square_no_text.svg

aDepartment of Chemistry, University of Leicester, Leicester LE1 7RH, England, bGlaxoSmithKline Pharmaceuticals, New Frontiers Science Park, Third Avenue, Harlow CM19 5AW, England, and cChroma Therapeutics Ltd, 93 Milton Park, Abingdon, Oxon OX14 4RY, England
*Correspondence e-mail: jmp29@leicester.ac.uk

(Received 11 July 2005; accepted 3 August 2005; online 21 September 2005)

The structure of the title compound, C15H25F2NO4, is presented. Comparison of this minor product with the isomeric major product of the synthesis is made in the previous paper.

Comment

The pseudorotational relationship between the ring conformations of the title compound, (2), and diol (1), which was presented in the previous paper (Fawcett et al., 2005[Fawcett, J., Percy, J. M., Pintat, S., Smith, C. A. & Uneyama, E. (2005). Acta Cryst. E61, o3319-o3321. ]), are discussed in the Comment of that paper.

[Scheme 1]

Hydrogen bonding (Table 1[link]) links mol­ecules of (2) into sheets perpendicular to the c axis.

[Figure 1]
Figure 1
The mol­ecular structure of (2), showing the atom-numbering scheme and 50% displacement ellipsoids. H atoms have been omitted.

Experimental

Compound (2) was obtained as the minor product during the preparation of diol (1), as described in the previous paper (Fawcett et al., 2005[Fawcett, J., Percy, J. M., Pintat, S., Smith, C. A. & Uneyama, E. (2005). Acta Cryst. E61, o3319-o3321. ]). A sample was recrystallized by vapour diffusion (ethyl acetate/light petroleum) to afford colourless crystals.

Crystal data
  • C15H25F2NO4

  • Mr = 321.36

  • Monoclinic, P 21 /c

  • a = 20.062 (14) Å

  • b = 6.433 (4) Å

  • c = 12.424 (9) Å

  • β = 97.346 (12)°

  • V = 1590.4 (19) Å3

  • Z = 4

  • Dx = 1.342 Mg m−3

  • Mo Kα radiation

  • Cell parameters from 3558 reflections

  • θ = 3.1–28.1°

  • μ = 0.11 mm−1

  • T = 150 (2) K

  • Block, colourless

  • 0.28 × 0.22 × 0.15 mm

Data collection
  • Bruker APEX CCD area-detector diffractometer

  • φ and ω scans

  • Absorption correction: none

  • 10968 measured reflections

  • 2805 independent reflections

  • 2413 reflections with I > 2σ(I)

  • Rint = 0.068

  • θmax = 25.0°

  • h = −23 → 23

  • k = −7 → 7

  • l = −14 → 14

Refinement
  • Refinement on F2

  • R[F2 > 2σ(F2)] = 0.039

  • wR(F2) = 0.095

  • S = 1.05

  • 2805 reflections

  • 205 parameters

  • H-atom parameters constrained

  • w = 1/[σ2(Fo2) + (0.045P)2 + 0.1172P] where P = (Fo2 + 2Fc2)/3

  • (Δ/σ)max = 0.003

  • Δρmax = 0.22 e Å−3

  • Δρmin = −0.21 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)[link]

D—H⋯A D—H H⋯A DA D—H⋯A
O1—H1⋯O4i 0.84 1.92 2.7598 (19) 173
O2—H2⋯O1ii 0.84 2.01 2.827 (2) 163
Symmetry codes: (i) [x, -y+{\script{3\over 2}}, z+{\script{1\over 2}}]; (ii) [x, -y+{\script{1\over 2}}, z-{\script{1\over 2}}].

H atoms were positioned geometrically, with C—H = 0.95–1.00 Å and O—H = 0.84 Å, and treated as riding, with Uiso(H) = 1.2 or 1.5 (methyl and OH) times Ueq of the parent atom.

Data collection: SMART (Bruker, 1997[Bruker (1997). SMART. Version 5.622. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 1999[Bruker (1999). SAINT. Version 6.02. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997[Sheldrick, G. M. (1997). SHELXS97 and SHELXL97. University of Göttingen, Germany.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997[Sheldrick, G. M. (1997). SHELXS97 and SHELXL97. University of Göttingen, Germany.]); molecular graphics: SHELXTL (Sheldrick, 2000[Sheldrick, G. M. (2000). SHELXTL. Version 6.10. Bruker AXS Inc., Madison, Wisconsin, USA.]); software used to prepare material for publication: SHELXTL.

Supporting information


Comment top

The pseudorotational relationship between the ring conformations of the title compound, (2), and diol (1), which was presented in the previous paper (Fawcett et al., 2005), are discussed in the Comment of that paper.

Hydrogen bonding (Table 1) links molecules of (2) into sheets perpendicular to the c axis.

Experimental top

Compound (2) was obtained as the minor product during the preparation of diol (1), as described in the previous paper (Fawcett et al., 2005). A sample was recrystallized by vapour diffusion (ethyl acetate/light petroleum) to afford colourless crystals.

Refinement top

H atoms were positioned geometrically, with C—H = 0.95–1.00 Å and O—H = 0.84 Å, and treated as riding, with Uiso(H) = 1.2 or 1.5 (methyl and OH) times Ueq of the parent atom.

Computing details top

Data collection: SMART (Bruker, 1997); cell refinement: SAINT (Bruker, 1999); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL (Sheldrick, 2000); software used to prepare material for publication: SHELXTL.

Figures top
[Figure 1] Fig. 1. The molecular structure of (2), showing the atom-numbering scheme and 50% displacement ellipsoids.
(1R*,3S*,8S*)-2,2-Difluoro-3,8-dihydroxy-5,5-dimethylcyclooct-4(Z)-en-1-yl N,N-diethylcarbamate top
Crystal data top
C15H25F2NO4F(000) = 688
Mr = 321.36Dx = 1.342 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 3558 reflections
a = 20.062 (14) Åθ = 3.1–28.1°
b = 6.433 (4) ŵ = 0.11 mm1
c = 12.424 (9) ÅT = 150 K
β = 97.346 (12)°Block, colourless
V = 1590.4 (19) Å30.28 × 0.22 × 0.15 mm
Z = 4
Data collection top
Bruker APEX CCD area-detector
diffractometer
2413 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.068
Graphite monochromatorθmax = 25.0°, θmin = 2.1°
ϕ and ω scansh = 2323
10968 measured reflectionsk = 77
2805 independent reflectionsl = 1414
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)] = 0.039Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.095H-atom parameters constrained
S = 1.05 w = 1/[σ2(Fo2) + (0.045P)2 + 0.1172P]
where P = (Fo2 + 2Fc2)/3
2805 reflections(Δ/σ)max = 0.003
205 parametersΔρmax = 0.22 e Å3
0 restraintsΔρmin = 0.21 e Å3
Crystal data top
C15H25F2NO4V = 1590.4 (19) Å3
Mr = 321.36Z = 4
Monoclinic, P21/cMo Kα radiation
a = 20.062 (14) ŵ = 0.11 mm1
b = 6.433 (4) ÅT = 150 K
c = 12.424 (9) Å0.28 × 0.22 × 0.15 mm
β = 97.346 (12)°
Data collection top
Bruker APEX CCD area-detector
diffractometer
2413 reflections with I > 2σ(I)
10968 measured reflectionsRint = 0.068
2805 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0390 restraints
wR(F2) = 0.095H-atom parameters constrained
S = 1.05Δρmax = 0.22 e Å3
2805 reflectionsΔρmin = 0.21 e Å3
205 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
F10.17709 (4)0.50429 (15)0.94617 (7)0.0317 (3)
F20.23221 (4)0.25700 (13)0.87715 (7)0.0289 (2)
N10.11443 (6)0.73451 (19)0.64634 (10)0.0253 (3)
O10.25363 (6)0.30397 (16)1.10013 (8)0.0279 (3)
H10.23290.37681.14100.042*
O20.30629 (6)0.58984 (17)0.66659 (8)0.0274 (3)
H20.28570.48690.63700.041*
O30.19811 (5)0.58723 (15)0.75457 (8)0.0234 (3)
O40.19503 (5)0.93651 (16)0.73795 (8)0.0269 (3)
C10.28505 (8)0.4356 (2)1.02965 (12)0.0228 (4)
H1A0.29080.57741.06250.027*
C20.23950 (7)0.4496 (2)0.92154 (12)0.0220 (3)
C30.25589 (7)0.6030 (2)0.83486 (11)0.0205 (3)
H30.25890.74680.86570.025*
C40.31992 (8)0.5554 (2)0.78015 (12)0.0226 (3)
H40.33150.40540.79230.027*
C50.38220 (7)0.6860 (2)0.82212 (12)0.0247 (4)
C60.39729 (8)0.6690 (3)0.94646 (12)0.0272 (4)
H6A0.44000.74200.97080.033*
H6B0.36120.73990.97970.033*
C70.40263 (8)0.4506 (3)0.98573 (13)0.0295 (4)
H70.44470.38230.98700.035*
C80.35268 (8)0.3461 (3)1.01882 (12)0.0269 (4)
H80.36010.20381.03710.032*
C90.17114 (8)0.7665 (2)0.71366 (12)0.0213 (3)
C100.09080 (8)0.5314 (2)0.60752 (13)0.0302 (4)
H10C0.04130.52590.60440.036*
H10D0.11010.42390.65940.036*
C110.10994 (10)0.4840 (3)0.49671 (15)0.0404 (5)
H11D0.09230.59280.44570.061*
H11E0.09100.34940.47180.061*
H11F0.15900.47890.50060.061*
C5"0.37228 (8)0.9155 (2)0.79324 (13)0.0313 (4)
H5"10.41090.99540.82740.047*
H5"20.33120.96610.81940.047*
H5"30.36840.93230.71430.047*
C5'0.44161 (8)0.6016 (3)0.77064 (14)0.0362 (4)
H5'10.43340.62130.69180.054*
H5'20.44710.45310.78700.054*
H5'30.48260.67600.80000.054*
C10'0.07636 (8)0.9164 (3)0.60459 (13)0.0293 (4)
H10A0.05140.88270.53280.035*
H10B0.10801.03080.59450.035*
C11'0.02753 (9)0.9882 (3)0.67924 (15)0.0388 (4)
H11A0.00450.87650.68830.058*
H11B0.00321.11050.64800.058*
H11C0.05211.02430.75010.058*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
F10.0218 (5)0.0425 (6)0.0322 (5)0.0031 (4)0.0085 (4)0.0033 (4)
F20.0379 (6)0.0228 (5)0.0260 (5)0.0057 (4)0.0036 (4)0.0032 (4)
N10.0254 (7)0.0247 (7)0.0240 (7)0.0031 (5)0.0035 (6)0.0010 (5)
O10.0360 (7)0.0256 (6)0.0239 (6)0.0017 (5)0.0103 (5)0.0029 (5)
O20.0351 (7)0.0288 (6)0.0183 (6)0.0051 (5)0.0033 (5)0.0025 (5)
O30.0223 (6)0.0212 (6)0.0245 (6)0.0004 (4)0.0047 (4)0.0001 (4)
O40.0336 (6)0.0208 (6)0.0256 (6)0.0015 (5)0.0014 (5)0.0010 (5)
C10.0275 (9)0.0207 (8)0.0206 (8)0.0006 (6)0.0048 (6)0.0007 (6)
C20.0207 (8)0.0200 (8)0.0261 (8)0.0004 (6)0.0059 (6)0.0043 (6)
C30.0194 (8)0.0209 (8)0.0198 (8)0.0015 (6)0.0026 (6)0.0022 (6)
C40.0272 (9)0.0217 (8)0.0187 (8)0.0001 (6)0.0030 (6)0.0000 (6)
C50.0229 (8)0.0267 (9)0.0246 (8)0.0010 (7)0.0029 (6)0.0002 (7)
C60.0201 (8)0.0337 (9)0.0267 (9)0.0033 (7)0.0011 (7)0.0005 (7)
C70.0231 (9)0.0373 (10)0.0268 (9)0.0054 (7)0.0010 (7)0.0035 (7)
C80.0301 (9)0.0272 (9)0.0224 (8)0.0062 (7)0.0000 (7)0.0036 (7)
C90.0249 (8)0.0229 (9)0.0170 (7)0.0022 (6)0.0058 (6)0.0006 (6)
C100.0259 (9)0.0295 (9)0.0329 (9)0.0039 (7)0.0049 (7)0.0017 (7)
C110.0435 (11)0.0362 (10)0.0392 (11)0.0071 (9)0.0028 (9)0.0101 (8)
C5"0.0304 (9)0.0305 (9)0.0316 (9)0.0067 (7)0.0004 (7)0.0028 (7)
C5'0.0285 (9)0.0458 (11)0.0357 (10)0.0012 (8)0.0098 (8)0.0024 (8)
C10'0.0305 (9)0.0324 (9)0.0242 (9)0.0080 (7)0.0008 (7)0.0038 (7)
C11'0.0407 (11)0.0425 (11)0.0342 (10)0.0126 (9)0.0087 (8)0.0031 (8)
Geometric parameters (Å, º) top
F1—C21.3722 (18)C6—H6A0.990
F2—C21.3564 (18)C6—H6B0.990
N1—C91.339 (2)C7—C81.316 (2)
N1—C101.451 (2)C7—H70.950
N1—C10'1.456 (2)C8—H80.950
O1—C11.4220 (18)C10—C111.507 (3)
O1—H10.840C10—H10C0.990
O2—C41.420 (2)C10—H10D0.990
O2—H20.840C11—H11D0.980
O3—C91.3458 (19)C11—H11E0.980
O3—C31.4329 (18)C11—H11F0.980
O4—C91.2167 (19)C5"—H5"10.980
C1—C81.496 (2)C5"—H5"20.980
C1—C21.528 (2)C5"—H5"30.980
C1—H1A1.000C5'—H5'10.980
C2—C31.527 (2)C5'—H5'20.980
C3—C41.559 (2)C5'—H5'30.980
C3—H31.000C10'—C11'1.505 (2)
C4—C51.540 (2)C10'—H10A0.990
C4—H41.000C10'—H10B0.990
C5—C5'1.523 (2)C11'—H11A0.980
C5—C5"1.526 (2)C11'—H11B0.980
C5—C61.540 (2)C11'—H11C0.980
C6—C71.487 (2)
C9—N1—C10124.15 (13)C6—C7—H7118.0
C9—N1—C10'117.66 (13)C7—C8—C1124.56 (15)
C10—N1—C10'118.09 (13)C7—C8—H8117.7
C1—O1—H1109.5C1—C8—H8117.7
C4—O2—H2109.5O4—C9—N1124.71 (14)
C9—O3—C3116.91 (12)O4—C9—O3123.38 (14)
O1—C1—C8107.74 (13)N1—C9—O3111.89 (13)
O1—C1—C2108.30 (13)N1—C10—C11112.04 (14)
C8—C1—C2113.03 (13)N1—C10—H10C109.2
O1—C1—H1A109.2C11—C10—H10C109.2
C8—C1—H1A109.2N1—C10—H10D109.2
C2—C1—H1A109.2C11—C10—H10D109.2
F2—C2—F1105.72 (12)H10C—C10—H10D107.9
F2—C2—C3108.99 (12)C10—C11—H11D109.5
F1—C2—C3106.05 (12)C10—C11—H11E109.5
F2—C2—C1108.96 (12)H11D—C11—H11E109.5
F1—C2—C1106.22 (12)C10—C11—H11F109.5
C3—C2—C1119.96 (13)H11D—C11—H11F109.5
O3—C3—C2102.53 (12)H11E—C11—H11F109.5
O3—C3—C4108.72 (12)C5—C5"—H5"1109.5
C2—C3—C4116.38 (12)C5—C5"—H5"2109.5
O3—C3—H3109.6H5"1—C5"—H5"2109.5
C2—C3—H3109.6C5—C5"—H5"3109.5
C4—C3—H3109.6H5"1—C5"—H5"3109.5
O2—C4—C5107.23 (12)H5"2—C5"—H5"3109.5
O2—C4—C3109.75 (12)C5—C5'—H5'1109.5
C5—C4—C3115.04 (12)C5—C5'—H5'2109.5
O2—C4—H4108.2H5'1—C5'—H5'2109.5
C5—C4—H4108.2C5—C5'—H5'3109.5
C3—C4—H4108.2H5'1—C5'—H5'3109.5
C5'—C5—C5"109.39 (13)H5'2—C5'—H5'3109.5
C5'—C5—C6109.39 (13)N1—C10'—C11'112.35 (14)
C5"—C5—C6107.91 (13)N1—C10'—H10A109.1
C5'—C5—C4107.92 (14)C11'—C10'—H10A109.1
C5"—C5—C4111.86 (13)N1—C10'—H10B109.1
C6—C5—C4110.35 (12)C11'—C10'—H10B109.1
C7—C6—C5113.14 (13)H10A—C10'—H10B107.9
C7—C6—H6A109.0C10'—C11'—H11A109.5
C5—C6—H6A109.0C10'—C11'—H11B109.5
C7—C6—H6B109.0H11A—C11'—H11B109.5
C5—C6—H6B109.0C10'—C11'—H11C109.5
H6A—C6—H6B107.8H11A—C11'—H11C109.5
C8—C7—C6124.04 (15)H11B—C11'—H11C109.5
C8—C7—H7118.0
O1—C1—C2—F261.47 (15)C3—C4—C5—C5"66.51 (17)
C8—C1—C2—F257.83 (16)O2—C4—C5—C6176.01 (12)
O1—C1—C2—F152.00 (15)C3—C4—C5—C653.64 (17)
C8—C1—C2—F1171.30 (12)C5'—C5—C6—C765.68 (17)
O1—C1—C2—C3172.00 (12)C5"—C5—C6—C7175.41 (13)
C8—C1—C2—C368.70 (18)C4—C5—C6—C752.91 (17)
C9—O3—C3—C2134.44 (12)C5—C6—C7—C895.27 (19)
C9—O3—C3—C4101.78 (14)C6—C7—C8—C14.8 (3)
F2—C2—C3—O360.55 (14)O1—C1—C8—C7160.47 (15)
F1—C2—C3—O352.85 (14)C2—C1—C8—C779.9 (2)
C1—C2—C3—O3172.94 (12)C10—N1—C9—O4172.08 (14)
F2—C2—C3—C457.97 (16)C10'—N1—C9—O44.1 (2)
F1—C2—C3—C4171.36 (11)C10—N1—C9—O39.8 (2)
C1—C2—C3—C468.55 (18)C10'—N1—C9—O3174.05 (12)
O3—C3—C4—O222.24 (16)C3—O3—C9—O43.3 (2)
C2—C3—C4—O2137.32 (13)C3—O3—C9—N1174.85 (12)
O3—C3—C4—C5143.24 (12)C9—N1—C10—C1197.16 (18)
C2—C3—C4—C5101.68 (16)C10'—N1—C10—C1178.99 (18)
O2—C4—C5—C5'64.51 (16)C9—N1—C10'—C11'87.16 (18)
C3—C4—C5—C5'173.12 (13)C10—N1—C10'—C11'96.43 (18)
O2—C4—C5—C5"55.86 (16)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1···O4i0.841.922.7598 (19)173
O2—H2···O1ii0.842.012.827 (2)163
Symmetry codes: (i) x, y+3/2, z+1/2; (ii) x, y+1/2, z1/2.

Experimental details

Crystal data
Chemical formulaC15H25F2NO4
Mr321.36
Crystal system, space groupMonoclinic, P21/c
Temperature (K)150
a, b, c (Å)20.062 (14), 6.433 (4), 12.424 (9)
β (°) 97.346 (12)
V3)1590.4 (19)
Z4
Radiation typeMo Kα
µ (mm1)0.11
Crystal size (mm)0.28 × 0.22 × 0.15
Data collection
DiffractometerBruker APEX CCD area-detector
diffractometer
Absorption correction
No. of measured, independent and
observed [I > 2σ(I)] reflections
10968, 2805, 2413
Rint0.068
(sin θ/λ)max1)0.595
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.039, 0.095, 1.05
No. of reflections2805
No. of parameters205
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.22, 0.21

Computer programs: SMART (Bruker, 1997), SAINT (Bruker, 1999), SAINT, SHELXS97 (Sheldrick, 1997), SHELXL97 (Sheldrick, 1997), SHELXTL (Sheldrick, 2000), SHELXTL.

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1···O4i0.841.922.7598 (19)173
O2—H2···O1ii0.842.012.827 (2)163
Symmetry codes: (i) x, y+3/2, z+1/2; (ii) x, y+1/2, z1/2.
 

Acknowledgements

The authors thank the Universities of Birmingham and Leicester, the EPSRC (project prant GR/K84882 for SP), GlaxoSmithKline (CASE studentship for SP) and Universities UK (ORS Award for EU).

References

First citationBruker (1997). SMART. Version 5.622. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
First citationBruker (1999). SAINT. Version 6.02. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
First citationFawcett, J., Percy, J. M., Pintat, S., Smith, C. A. & Uneyama, E. (2005). Acta Cryst. E61, o3319–o3321.  Web of Science CSD CrossRef IUCr Journals Google Scholar
First citationSheldrick, G. M. (1997). SHELXS97 and SHELXL97. University of Göttingen, Germany.  Google Scholar
First citationSheldrick, G. M. (2000). SHELXTL. Version 6.10. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar

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