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

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ISSN: 2414-3146

9-Fluoro-2,4,4a,6-tetra­hydro­spiro­[benzo[c]chromene-3,2′-[1,3]dioxolane]

CROSSMARK_Color_square_no_text.svg

aDepartment of Physics, Thiagarajar College, Madurai 625 009, India, and bDepartment of Physics, M.G.R. College, Hosur 635 109, India
*Correspondence e-mail: vasan692000@yahoo.co.in

Edited by P. C. Healy, Griffith University, Australia (Received 3 January 2017; accepted 10 January 2017; online 17 January 2017)

In the title compound, C15H15FO3, the dihedral angle between the mean plane through all the non-H atoms of the dioxolane ring with those of the rest of the atoms of the chromene ring system, including the substituent F atom, is 81.1 (1)°. The pyran ring has an envelope conformation with the O atom as the flap. The cyclo­hexene ring has a half-chair conformation, while the dioxolane ring has a twisted conformation on an –O—CH2– bond. In the crystal, mol­ecules are linked via C—H⋯O hydrogen bonds, forming chains along [100]. The chains are linked by C—H⋯π inter­actions, involving the fluoro­benzene ring, forming layers parallel to the ac plane.

3D view (loading...)
[Scheme 3D1]
Chemical scheme
[Scheme 1]

Structure description

The title compound belongs to a novel class of spiro heterocycles consisting of a chromene ring system with a fused 4-fluoro­benzene on one side and a spiro-fused 1,3-dioxolane ring on the other. Several dioxolane–indoline derivatives are known to be anti­convulsants (Rajopadhye & Popp, 1988[Rajopadhye, M. & Popp, F. D. (1988). J. Med. Chem. 31, 1001-1005.]) and the crystal structures of a few of them, closely related to the title compound, have been elucidated (De, 2008[De, A. (2008). Acta Cryst. E64, o562.]; Bjerrum et al., 2009[Bjerrum, J. V., Ulven, T. & Bond, A. D. (2009). Acta Cryst. E65, o579.]; Meng & Miao, 2010[Meng, Y. & Miao, Y. (2010). Acta Cryst. E66, o1305.]; Wang et al., 2010[Wang, K., Yang, W., Wang, L.-L., Zhu, J. & Hu, Y. (2010). Acta Cryst. E66, o2431.]). Chromene scaffolds are basic components of innumerable natural products which exhibit a variety of biological activities, in particular as anti-JH activity in the context of safe inspect-specific pesticides (Bowers et al., 1976[Bowers, W. S., Ohta, T., Cleere, J. S. & Marsella, P. A. (1976). Science, 193, 542-547.]) and anti­protozoal agents (Harel et al., 2013[Harel, D., Schepmann, D., Prinz, H., Brun, R., Schmidt, T. J. & Wünsch, B. (2013). J. Med. Chem. 56, 7442-7448.]). In a recent study, several chromene derivatives were evaluated and shown to possess anti­proliferative activity against cancer cells (Parthiban et al., 2016[Parthiban, A., Kumaravel, M., Muthukumaran, J., Rukkumani, R., Krishna, R. & Rao, H. S. P. (2016). Med. Chem. Res. 25, 1308-1315.]). The importance of chromene as a promising pharmacophore with numerous activities such as anti­cancer, anti­microbial, anti­viral, anti-inflammatory, anti­oxidant and anti­thrombotic was emphasized in a recent review on structurally diversified chromenes (Costa et al., 2016[Costa, M., Dias, T., Brito, A. & Proença, F. (2016). Eur. J. Med. Chem. 123, 487-507.]). 1,3-Dioxolane is regarded as a green solvent as it produces stable carbon nanotube dispersions, which leave no residue on electrodes when it evaporates (Moscoso et al., 2014[Moscoso, R., Carbajo, J. & Squella, J. A. (2014). Electrochem. Commun. 48, 69-72.]). A survey of the Cambridge Structural Database (Groom et al., 2016[Groom, C. R., Bruno, I. J., Lightfoot, M. P. & Ward, S. C. (2016). Acta Cryst. B72, 171-179.]) shows that crystal structures incorporating spiro-fused dioxolane-chromene ring systems are scarce and, to the best of our knowledge, the title structure is the first of its kind. Details of its mol­ecular and crystal structure are presented herein.

The mol­ecular structure of the title compound is shown in Fig. 1[link]. The dihedral angle between the mean plane through all non-H atoms of the dioxolane ring with those of the rest of the fused benzo[c]chromene unit, including atom F1, is 81.1 (1)°. The puckering parameters of the pyran ring (O3/C5–C7/C12/C13), viz. Q = 0.5012 (2) Å, θ = 129.8 (2)° and φ = 196.7 (3)°, describe a distorted envelope conformation. Those for the cyclo­hexene ring (C3/C4/C5/C13/C14/C15), viz. Q = 0.480 (2) Å, θ = 130.4 (2)° and φ = 212.8 (3)°, described a half-chair conformation. The dioxolane ring (C3/C2/C1/O1/O2) has a slightly twisted conformation about the C2—O2 bond, and is close to 3T4 with puckering parameters of Q = 0.295 (2) Å and φ = 98.2 (2)°.

[Figure 1]
Figure 1
The mol­ecular structure of the title compound, showing the atom-labelling scheme and 50% probability displacement ellipsoids.

In the crystal, mol­ecules are linked by C—H⋯O hydrogen bonds, involving the pyran O atom, O3, forming chains propagating along the a-axis direction (Table 1[link] and Fig. 2[link]). The chains are linked by C—H⋯π inter­actions, forming layers parallel to the ac plane (Table 1[link] and Fig. 3[link]).

Table 1
Hydrogen-bond geometry (Å, °)

Cg is the centroid of the C7–C12 benzene ring.

D—H⋯A D—H H⋯A DA D—H⋯A
C15—H15B⋯O3i 0.97 2.52 3.448 (2) 161
C4—H4ACgii 0.97 2.99 3.933 (3) 164
Symmetry codes: (i) x+1, y, z; (ii) [x, -y+{\script{1\over 2}}, z-{\script{1\over 2}}].
[Figure 2]
Figure 2
A partial view along the c axis of the crystal packing of the title compound, showing the hydrogen-bonded chains propagating along the a axis. Hydrogen bonds (see Table 1[link]) are shown as dashed lines, and only H atoms H15B and H4A have been included.
[Figure 3]
Figure 3
A view along the c axis of the crystal packing of the title compound. Hydrogen bonds (see Table 1[link]) are shown as dashed lines, and only H atoms H15B and H4A have been included. The C—H⋯π inter­actions involve the fluoro­benzene rings (see Table 1[link]).

Synthesis and crystallization

To a solution of 8-[5-fluoro-2-(hy­droxy­meth­yl)phen­yl]-1,4-dioxa­spiro­[4,5]dec-8-en-7-ol (100 mmol) in dry THF (10 vol), cooled to 273 K, was added tri­phenyl­phosphane (15 mmol) and diisopropyl azodi­carboxyl­ate (120 mmol) under N2. The reaction mixture was heated to 353 K for 6 h. The reaction mixture was quenched with ice and extracted with ethyl acetate, washed with saturated brine solution, dried over sodium sulfate and concentrated under vacuum. The crude product was purified by flash chromatography (silica gel, 50% EtOAc in hexa­nes), to give the title compound as colourless needle-like crystals on evaporation of the solvent.

Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2[link].

Table 2
Experimental details

Crystal data
Chemical formula C15H15FO3
Mr 262.28
Crystal system, space group Monoclinic, P21/c
Temperature (K) 295
a, b, c (Å) 7.0373 (4), 20.7068 (14), 8.4725 (6)
β (°) 92.088 (3)
V3) 1233.79 (14)
Z 4
Radiation type Mo Kα
μ (mm−1) 0.11
Crystal size (mm) 0.30 × 0.23 × 0.18
 
Data collection
Diffractometer Bruker SMART APEXII CCD
Absorption correction Multi-scan (SADABS; Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.])
Tmin, Tmax 0.978, 0.986
No. of measured, independent and observed [I > 2σ(I)] reflections 23436, 2802, 1702
Rint 0.045
(sin θ/λ)max−1) 0.650
 
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.045, 0.121, 1.01
No. of reflections 2802
No. of parameters 173
H-atom treatment H-atom parameters constrained
Δρmax, Δρmin (e Å−3) 0.23, −0.20
Computer programs: APEX2 and SAINT (Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]), SHELXS2013/1 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]), SHELXL2013/1 (Sheldrick, 2015[Sheldrick, G. M. (2015). Acta Cryst. C71, 3-8.]), PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]) and publCIF (Westrip, 2010[Westrip, S. P. (2010). J. Appl. Cryst. 43, 920-925.]).

Structural data


Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXS2013/1 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2013/1 (Sheldrick, 2015); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: publCIF (Westrip, 2010).

9-Fluoro-2,4,4a,6-tetrahydrospiro[benzo[c]chromene-3,2'-[1,3]dioxolane] top
Crystal data top
C15H15FO3F(000) = 552
Mr = 262.28Dx = 1.412 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
a = 7.0373 (4) ÅCell parameters from 2803 reflections
b = 20.7068 (14) Åθ = 1.0–27.8°
c = 8.4725 (6) ŵ = 0.11 mm1
β = 92.088 (3)°T = 295 K
V = 1233.79 (14) Å3Needle, colourless
Z = 40.30 × 0.23 × 0.18 mm
Data collection top
Bruker Smart APEXII CCD
diffractometer
1702 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.045
φ and ω scansθmax = 27.5°, θmin = 2.6°
Absorption correction: multi-scan
(SADABS; Bruker, 2009)
h = 98
Tmin = 0.978, Tmax = 0.986k = 2626
23436 measured reflectionsl = 1111
2802 independent reflections
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.045H-atom parameters constrained
wR(F2) = 0.121 w = 1/[σ2(Fo2) + (0.0413P)2 + 0.5912P]
where P = (Fo2 + 2Fc2)/3
S = 1.01(Δ/σ)max < 0.001
2802 reflectionsΔρmax = 0.23 e Å3
173 parametersΔρmin = 0.20 e Å3
0 restraintsExtinction correction: SHELXL-2013/1 (Sheldrick, 2015), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.0044 (11)
Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
F10.63642 (19)0.01685 (6)0.13314 (18)0.0690 (4)
O10.89547 (19)0.36864 (7)0.30809 (15)0.0458 (4)
O20.86401 (19)0.43734 (7)0.10063 (17)0.0507 (4)
O30.34019 (17)0.30048 (6)0.20342 (15)0.0381 (3)
C11.0345 (3)0.41731 (11)0.3309 (3)0.0524 (6)
H1A1.15680.39850.36090.063*
H1B0.99820.44720.41280.063*
C21.0432 (3)0.45101 (12)0.1753 (3)0.0562 (6)
H2A1.06080.49710.18950.067*
H2B1.14610.43420.11410.067*
C30.8108 (3)0.37529 (9)0.1533 (2)0.0376 (5)
C40.5986 (3)0.37102 (9)0.1610 (3)0.0418 (5)
H4A0.54130.37580.05580.050*
H4B0.55250.40580.22620.050*
C50.5414 (2)0.30716 (9)0.2291 (2)0.0314 (4)
H50.57070.30750.34300.038*
C60.2724 (3)0.24662 (9)0.2886 (2)0.0388 (5)
H6A0.13670.24210.26750.047*
H6B0.29300.25430.40090.047*
C70.3699 (3)0.18527 (9)0.2448 (2)0.0338 (4)
C80.2831 (3)0.12635 (10)0.2685 (3)0.0472 (5)
H80.16250.12530.30980.057*
C90.3712 (3)0.06928 (11)0.2324 (3)0.0523 (6)
H90.31290.02970.24960.063*
C100.5467 (3)0.07270 (10)0.1707 (3)0.0463 (5)
C110.6385 (3)0.12945 (10)0.1444 (2)0.0400 (5)
H110.75850.12950.10190.048*
C120.5501 (2)0.18748 (9)0.1821 (2)0.0318 (4)
C130.6407 (2)0.25062 (9)0.1568 (2)0.0307 (4)
C140.7963 (3)0.25918 (10)0.0756 (2)0.0376 (5)
H140.85340.22290.03340.045*
C150.8856 (3)0.32319 (10)0.0475 (2)0.0406 (5)
H15A0.86170.33550.06190.049*
H15B1.02210.31960.06540.049*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
F10.0713 (9)0.0369 (8)0.0983 (11)0.0132 (7)0.0042 (8)0.0096 (7)
O10.0481 (8)0.0513 (9)0.0376 (8)0.0185 (7)0.0033 (6)0.0042 (6)
O20.0455 (8)0.0425 (9)0.0635 (10)0.0123 (7)0.0051 (7)0.0165 (7)
O30.0275 (7)0.0374 (8)0.0496 (8)0.0016 (6)0.0034 (6)0.0049 (6)
C10.0508 (13)0.0471 (14)0.0588 (14)0.0138 (11)0.0034 (11)0.0039 (11)
C20.0477 (13)0.0528 (15)0.0681 (15)0.0177 (11)0.0005 (11)0.0059 (12)
C30.0361 (10)0.0362 (11)0.0402 (10)0.0058 (9)0.0024 (8)0.0085 (8)
C40.0351 (11)0.0343 (11)0.0557 (12)0.0009 (9)0.0008 (9)0.0034 (9)
C50.0245 (9)0.0331 (11)0.0366 (9)0.0003 (8)0.0000 (7)0.0007 (8)
C60.0304 (10)0.0408 (12)0.0458 (11)0.0021 (9)0.0083 (8)0.0034 (9)
C70.0343 (10)0.0346 (11)0.0324 (9)0.0012 (8)0.0006 (8)0.0007 (8)
C80.0425 (12)0.0452 (13)0.0543 (13)0.0058 (10)0.0085 (10)0.0022 (10)
C90.0568 (14)0.0353 (13)0.0647 (15)0.0093 (11)0.0015 (11)0.0033 (11)
C100.0524 (13)0.0312 (12)0.0546 (13)0.0082 (10)0.0070 (10)0.0052 (10)
C110.0369 (11)0.0401 (12)0.0430 (11)0.0041 (9)0.0007 (9)0.0016 (9)
C120.0322 (10)0.0341 (11)0.0289 (9)0.0023 (8)0.0020 (7)0.0003 (8)
C130.0271 (9)0.0350 (10)0.0298 (9)0.0012 (8)0.0022 (7)0.0005 (7)
C140.0323 (10)0.0401 (12)0.0405 (11)0.0009 (8)0.0028 (8)0.0050 (9)
C150.0325 (10)0.0526 (13)0.0370 (10)0.0059 (9)0.0039 (8)0.0031 (9)
Geometric parameters (Å, º) top
F1—C101.361 (2)C6—C71.497 (3)
O1—C11.413 (2)C6—H6A0.9700
O1—C31.427 (2)C6—H6B0.9700
O2—C31.415 (2)C7—C81.382 (3)
O2—C21.419 (2)C7—C121.393 (2)
O3—C61.420 (2)C8—C91.374 (3)
O3—C51.431 (2)C8—H80.9300
C1—C21.495 (3)C9—C101.361 (3)
C1—H1A0.9700C9—H90.9300
C1—H1B0.9700C10—C111.363 (3)
C2—H2A0.9700C11—C121.395 (3)
C2—H2B0.9700C11—H110.9300
C3—C41.500 (3)C12—C131.474 (3)
C3—C151.510 (3)C13—C141.326 (2)
C4—C51.503 (3)C14—C151.490 (3)
C4—H4A0.9700C14—H140.9300
C4—H4B0.9700C15—H15A0.9700
C5—C131.505 (2)C15—H15B0.9700
C5—H50.9800
C1—O1—C3108.71 (15)C7—C6—H6A109.2
C3—O2—C2106.36 (15)O3—C6—H6B109.2
C6—O3—C5110.31 (14)C7—C6—H6B109.2
O1—C1—C2105.23 (17)H6A—C6—H6B107.9
O1—C1—H1A110.7C8—C7—C12119.84 (18)
C2—C1—H1A110.7C8—C7—C6120.27 (17)
O1—C1—H1B110.7C12—C7—C6119.88 (17)
C2—C1—H1B110.7C9—C8—C7121.4 (2)
H1A—C1—H1B108.8C9—C8—H8119.3
O2—C2—C1103.62 (17)C7—C8—H8119.3
O2—C2—H2A111.0C10—C9—C8117.7 (2)
C1—C2—H2A111.0C10—C9—H9121.2
O2—C2—H2B111.0C8—C9—H9121.2
C1—C2—H2B111.0C9—C10—F1118.76 (19)
H2A—C2—H2B109.0C9—C10—C11123.34 (19)
O2—C3—O1105.74 (15)F1—C10—C11117.90 (19)
O2—C3—C4110.03 (16)C10—C11—C12119.15 (19)
O1—C3—C4109.72 (16)C10—C11—H11120.4
O2—C3—C15111.08 (16)C12—C11—H11120.4
O1—C3—C15109.50 (16)C7—C12—C11118.59 (17)
C4—C3—C15110.65 (16)C7—C12—C13119.29 (16)
C3—C4—C5110.45 (15)C11—C12—C13122.12 (16)
C3—C4—H4A109.6C14—C13—C12124.32 (17)
C5—C4—H4A109.6C14—C13—C5120.78 (17)
C3—C4—H4B109.6C12—C13—C5114.90 (15)
C5—C4—H4B109.6C13—C14—C15124.24 (18)
H4A—C4—H4B108.1C13—C14—H14117.9
O3—C5—C4107.68 (14)C15—C14—H14117.9
O3—C5—C13109.54 (14)C14—C15—C3112.52 (16)
C4—C5—C13113.16 (15)C14—C15—H15A109.1
O3—C5—H5108.8C3—C15—H15A109.1
C4—C5—H5108.8C14—C15—H15B109.1
C13—C5—H5108.8C3—C15—H15B109.1
O3—C6—C7112.04 (15)H15A—C15—H15B107.8
O3—C6—H6A109.2
C3—O1—C1—C24.9 (2)C8—C9—C10—C110.5 (3)
C3—O2—C2—C132.3 (2)C9—C10—C11—C120.0 (3)
O1—C1—C2—O222.7 (2)F1—C10—C11—C12179.87 (17)
C2—O2—C3—O129.8 (2)C8—C7—C12—C110.1 (3)
C2—O2—C3—C4148.23 (18)C6—C7—C12—C11179.13 (16)
C2—O2—C3—C1588.89 (19)C8—C7—C12—C13179.76 (17)
C1—O1—C3—O214.9 (2)C6—C7—C12—C131.2 (3)
C1—O1—C3—C4133.47 (17)C10—C11—C12—C70.3 (3)
C1—O1—C3—C15104.90 (18)C10—C11—C12—C13179.96 (18)
O2—C3—C4—C5175.51 (16)C7—C12—C13—C14168.76 (18)
O1—C3—C4—C559.6 (2)C11—C12—C13—C1410.9 (3)
C15—C3—C4—C561.4 (2)C7—C12—C13—C510.4 (2)
C6—O3—C5—C4169.93 (15)C11—C12—C13—C5169.99 (16)
C6—O3—C5—C1366.62 (18)O3—C5—C13—C14137.18 (17)
C3—C4—C5—O3168.26 (15)C4—C5—C13—C1417.0 (2)
C3—C4—C5—C1347.0 (2)O3—C5—C13—C1242.0 (2)
C5—O3—C6—C757.3 (2)C4—C5—C13—C12162.16 (15)
O3—C6—C7—C8156.86 (17)C12—C13—C14—C15178.77 (17)
O3—C6—C7—C1224.1 (2)C5—C13—C14—C150.3 (3)
C12—C7—C8—C90.4 (3)C13—C14—C15—C314.2 (3)
C6—C7—C8—C9178.6 (2)O2—C3—C15—C14166.59 (15)
C7—C8—C9—C100.7 (3)O1—C3—C15—C1476.99 (19)
C8—C9—C10—F1179.63 (19)C4—C3—C15—C1444.1 (2)
Hydrogen-bond geometry (Å, º) top
Cg is the centroid of the C7–C12 benzene ring.
D—H···AD—HH···AD···AD—H···A
C15—H15B···O3i0.972.523.448 (2)161
C4—H4A···Cgii0.972.993.933 (3)164
Symmetry codes: (i) x+1, y, z; (ii) x, y+1/2, z1/2.
 

Acknowledgements

The authors thank the Sophisticated Analytical Instrumentation Centre (SAIF), Indian Institute of Technology (IIT), Chennai, for the X-ray intensity data collection and the School of Physics, Madurai Kamaraj University, Madurai, for access to the Cambridge Structural Database.

References

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