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Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 72| Part 1| January 2016| Pages 106-108
doi:10.1107/S2056989015024512

Crystal structure of 7,8,9,10-tetra­hydro­benzo[b]naphtho­[2,1-d]furan

CROSSMARK_Color_square_no_text.svg
Zhongyuan Wu,a,b Manfred T. Reetza,b* and Klaus Harmsa*

aFachbereich Chemie, Philipps-Universität, Hans-Meerwein-Strasse 4, 35032 Marburg, Germany, and bMax-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim, Germany
*Correspondence e-mail: reetz@mpi-muelheim.mpg.de, klaus.harms@chemie.uni-marburg.de

Edited by H. Stoeckli-Evans, University of Neuchâtel, Switzerland (Received 15 December 2015; accepted 21 December 2015; online 1 January 2016)

In the title compound, C16H14O, the cyclo­hexene ring has a half-chair conformation. The mean plane, calculated through all non-H atoms of the mol­ecule, except for the central CH2 atoms of the cyclo­hexene ring, which deviate by 0.340 (3) and −0.369 (3) Å from this mean plane, has an r.m.s. deviation of 0.012 Å. In the crystal, there are C—H⋯π contacts present, resulting in the formation of zigzag chains propagating along the [010] direction.

CCDC reference: 1429774

Similar articles

1. Chemical context

The inter­action of Lewis acids with 1-naphthol 1 can be expected to induce metal coordination at the hy­droxy function with concomitant increase in Brønsted-acidity (2) (Yamamoto & Futatsugi, 2005[Yamamoto, H. & Futatsugi, K. (2005). Angew. Chem. Int. Ed. 44, 1924-1942.]; Goering, 1995[Goering, B. K. (1995). PhD dissertation, Cornell University, Ithaca, USA.]). It is conceivable that the proton, once released from this inter­mediate 2, adds reversibly to the 4-position with formation of adduct 3, which is the Lewis acid coordinated form of the keto-tautomer of 1. Even if only minute amounts of 3 were to be formed, this inter­mediate should be a highly reactive dienophile in Diels–Alder reactions with such dienes as cyclo­hexa­diene 4 leading to adduct 5 (see Scheme). Such a transformation implies de-aromatization of 1-naphthol 1.

[Scheme 1]

Alternatively, protonation of diene 4 leading to carbocation 6 would set the stage for Friedel–Crafts reaction with formation of the alkyl­ation product 7, which could continue to react acid catalyzed, leading to adduct 8 and possibly to the aromatized furan product 9. In a previous study, Novák and coworkers reported the reaction of 1 with 4 in the presence of TsOH·H2O in boiling toluene (26 h) or at room temperature (7 d), furan derivative 9 being formed in 58% yield, presumably via the inter­mediacy of 7 and 8 (Orovecz et al., 2003[Orovecz, O., Kovács, P., Kolonits, P., Kaleta, Z., Párkányi, L., Szabó, É. & Novák, L. (2003). Synthesis, 7, 1043-1048.]; Novák et al., 2000[Novák, L., Kovács, P., Kolonits, P., Orovecz, O., Fekete, J. & Szántay, C. (2000). Synthesis, 6, 809-812.]).

In exploratory experiments, we tested Et2O·BF3, FeCl3, TiCl4 and ZrCl4 as Lewis acids in the reaction of 1 and 4 at room temperature in CH2Cl2. Essentially only products derived from formal Friedel–Crafts alkyl­ation were identified following column chromatographic separation. Small amounts of unidentified compounds which could not be separated were also formed. A general protocol is provided. If a 2.5-fold excess of cyclo­hexa­diene 4 is used in these reactions, only small amounts of Friedel–Crafts products are formed (3–4%). Rather, acid-mediated oligomerization of diene 4 occurs.

In contrast to the acidic conditions employed by Novák and coworkers, using the present protocol we isolated compound 8 and characterized it for the first time. We report herein on the crystal structure of the final product, furan 9.

2. Structural commentary

In the title compound 9, illustrated in Fig. 1[link], the cyclo­hexene ring (C1–C6) has a half-chair conformation. The mean plane, calculated through all non-hydrogen atoms of the mol­ecule (O1/C1/C2/C5–C16), except atoms C3 and C4 of the cyclo­hexene ring that deviate by 0.340 (3) and −0.369 (3) Å from this mean plane, has an r.m.s. deviation of 0.012 Å. The other C and O atoms lie in this mean plane with a maximum deviation of −0.051 (3) Å for atom C2.

[Figure 1]
Figure 1
The mol­ecular structure of compound 9, showing the atom labelling. Displacement ellipsoids are drawn at the 50% probability level.

3. Supra­molecular features

In the crystal of 9, there are C—H⋯π contacts present (Table 1[link] and Fig. 2[link]), but no classical hydrogen bonds and no π–π inter­actions present. Inter­molecular contacts thus appear to be limited to van der Waals inter­actions. The two rather short inter­molecular C—H⋯ring centroid distances are: H5B⋯centroid of ring (C10–C15) = 2.69 Å, H8⋯centroid of ring (C7–C10/C15/C16) = 2.93 Å. These inter­actions result in the formation of zigzag chains propagating along the b-axis direction.

Table 1
Hydrogen-bond geometry (Å, °)

Cg3 and Cg4 are the centroids of rings C7–C10/C15/C16 and C10–C15, respectively.
D—H⋯A D—H H⋯A D⋯A D—H⋯A
C5—H5B⋯Cg4i 0.99 2.69 3.664 (3) 167
C8—H8⋯Cg3i 0.95 2.93 3.650 (3) 134
Symmetry code: (i) [-x, -y+2, z-{\script{1\over 2}}].
[Figure 2]
Figure 2
A view of the nearest C—H⋯ring centroid distances, shown as dashed lines [see Table 1[link]; symmetry code: (i) −x, −y + 2, z − [{1\over 2}]].

4. Database survey

Only one structure of a tetra­hydro­benzo­naphtho­furan (Refcode PEBDAD; Scully & Porco, 2012[Scully, S. S. & Porco, J. A. Jr (2012). Org. Lett. 14, 2646-2649.]) is present in the current version 5.36 of the CSD (Groom & Allen, 2014[Groom, C. R. & Allen, F. H. (2014). Angew. Chem. Int. Ed. 53, 662-671.]), and the cyclo­hexene ring also has a half-chair conformation.

5. Synthesis and crystallization

General Procedure: To a mixture of 1-naphthol (6.48 g, 45 mmol), catalyst (2.25 mmol) in CH2Cl2 (10 ml), 1,3-cyclo­hexa­diene (0.7 ml, 22.5 mmol) in CH2Cl2 (30 ml) was added drop wise, and the resulting solution was stirred at 273 K for 5 h. After completion of the reaction (TLC) at room temperature, a cold aqueous solution of NaHCO3 (5%, 20 ml) was added and the mixture was extracted with CH2Cl2 (3 × 10 ml). The organic extracts were washed with water (2 ×10 mL) and dried over anhydrous Na2SO4, and concentrated in vacuum. The crude product was purified by silica column chromatography (petroleum ether) to give the desired product, which was identified by NMR spectroscopic comparison with authentic samples of 1, 2 and by X-ray diffraction analysis (Fig. 1[link]).

Compound 8: 1H NMR (300 MHz, CDCl3, p.p.m.): δ 1.19–1.27 (m, 1H), 1.34–1.48 (m, 4H), 1.69–1.84 (m, 2H), 1.92–2.02 (m, 1H), 3.17–3.24 (m, 1H), 4.71--4.77 (m, 1H), 7.16–7.18 (m, 1H), 7.24–7.32 (m, 3H), 7.66–7.69 (m, 1H), 7.87–7.90 (m, 1H); 13C NMR (300 MHz, CDCl3, p.p.m.): δ 20.50, 21.86, 27.64, 28.38, 41.41, 83.44, 120.16, 121.16, 121.60, 121.92, 125.13, 125.48, 126.55, 128.01, 134.11, 155.07.

High Resolution Mass Spectrum: (M + H+) calculated for C16H16O 225.1274; found (M + H+) 225.1275.

6. Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2[link]. H atoms were located in difference Fourier maps, but subsequently included in the refinement using a riding model: C–H = 0.95-0.99 Å with Uiso(H) = 1.2Ueq(C).

Table 2
Experimental details

Crystal data
Chemical formula C16H14O
Mr 222.27
Crystal system, space group Orthorhombic, Pna21
Temperature (K) 100
a, b, c (Å) 13.8369 (9), 12.2202 (8), 6.8468 (4)
V (Å3) 1157.72 (13)
Z 4
Radiation type Mo Kα
μ (mm−1) 0.08
Crystal size (mm) 0.16 × 0.05 × 0.04
 
Data collection
Diffractometer Bruker D8 QUEST area detector
Absorption correction Multi-scan (SADABS; Bruker, 2014[Bruker (2014). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.])
Tmin, Tmax 0.94, 1.00
No. of measured, independent and observed [I > 2σ(I)] reflections 5983, 2024, 1808
Rint 0.038
(sin θ/λ)max (Å−1) 0.601
 
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.038, 0.081, 1.09
No. of reflections 2024
No. of parameters 154
No. of restraints 1
H-atom treatment H-atom parameters constrained
Δρmax, Δρmin (e Å−3) 0.16, −0.24
Computer programs: APEX2 and SAINT (Bruker, 2014[Bruker (2014). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]), SHELXT (Sheldrick, 2015a[Sheldrick, G. M. (2015a). Acta Cryst. A71, 3-8.]), SHELXL (Sheldrick, 2015b[Sheldrick, G. M. (2015b). Acta Cryst. C71, 3-8.]), DIAMOND (Brandenburg, 2006[Brandenburg, K. (2006). DIAMOND. Crystal Impact GbR, Bonn, Germany.]), publCIF (Westrip, 2010[Westrip, S. P. (2010). J. Appl. Cryst. 43, 920-925.]) and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

Supporting information

CCDC reference: 1429774

Crystal structure: contains datablock I. DOI: 10.1107/S2056989015024512/su5264sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S2056989015024512/su5264Isup2.hkl

Supporting information file. DOI: 10.1107/S2056989015024512/su5264Isup3.cml

checkCIF report


Computing details top

Data collection: APEX2 (Bruker, 2014); cell refinement: SAINT (Bruker, 2014); data reduction: SAINT (Bruker, 2014); program(s) used to solve structure: SHELXT (Sheldrick, 2015a); program(s) used to refine structure: SHELXL (Sheldrick, 2015b); molecular graphics: DIAMOND (Brandenburg, 2006); software used to prepare material for publication: publCIF (Westrip, 2010) and PLATON (Spek, 2009).

7,8,9,10-Tetrahydrobenzo[b]naphtho[2,1-d]furan top
Crystal data top
C16H14ODx = 1.275 Mg m−3
Mr = 222.27Mo Kα radiation, λ = 0.71073 Å
Orthorhombic, Pna21Cell parameters from 2867 reflections
a = 13.8369 (9) Åθ = 2.2–25.2°
b = 12.2202 (8) ŵ = 0.08 mm−1
c = 6.8468 (4) ÅT = 100 K
V = 1157.72 (13) Å3Prism, colourless
Z = 40.16 × 0.05 × 0.04 mm
F(000) = 472
Data collection top
Bruker D8 QUEST area-detector
diffractometer		2024 independent reflections
Radiation source: microfocus sealed X-ray tube1808 reflections with I > 2σ(I)
Detector resolution: 7.9 pixels mm-1Rint = 0.038
ω and φ scansθmax = 25.3°, θmin = 2.2°
Absorption correction: multi-scan
(SADABS; Bruker, 2014)		h = −16→16
Tmin = 0.94, Tmax = 1.00k = −14→14
5983 measured reflectionsl = −8→8
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)] = 0.038Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.081H-atom parameters constrained
S = 1.09 w = 1/[σ2(Fo2) + (0.0435P)2 + 0.0066P]
where P = (Fo2 + 2Fc2)/3
2024 reflections(Δ/σ)max < 0.001
154 parametersΔρmax = 0.16 e Å−3
1 restraintΔρmin = −0.24 e Å−3
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
C10.03747 (16)0.7566 (2)0.3738 (4)0.0159 (5)
O10.09729 (11)0.83253 (13)0.4640 (2)0.0165 (4)
C20.00207 (19)0.6599 (2)0.4844 (4)0.0207 (6)
H2A−0.04920.68220.57700.025*
H2B0.05570.62670.55960.025*
C3−0.03802 (19)0.5773 (2)0.3369 (4)0.0237 (6)
H3A−0.07670.52150.40700.028*
H3B0.01640.53950.27160.028*
C4−0.10145 (19)0.6329 (2)0.1823 (4)0.0232 (6)
H4A−0.13000.57630.09640.028*
H4B−0.15510.67190.24800.028*
C5−0.04412 (18)0.7140 (2)0.0581 (4)0.0179 (6)
H5A−0.00360.6738−0.03690.021*
H5B−0.08910.7616−0.01560.021*
C60.01857 (16)0.78260 (19)0.1870 (4)0.0138 (5)
C70.06900 (16)0.8841 (2)0.1498 (3)0.0137 (5)
C80.07806 (17)0.9549 (2)−0.0120 (4)0.0165 (6)
H80.04750.9381−0.13260.020*
C90.13190 (18)1.0484 (2)0.0084 (4)0.0187 (6)
H90.13711.0973−0.09910.022*
C100.18051 (17)1.07448 (19)0.1866 (4)0.0171 (6)
C110.23745 (18)1.1700 (2)0.2054 (4)0.0215 (6)
H110.24411.21790.09690.026*
C120.28309 (18)1.1947 (2)0.3768 (4)0.0243 (7)
H120.32091.25930.38620.029*
C130.27444 (18)1.1254 (2)0.5383 (4)0.0234 (6)
H130.30601.14380.65710.028*
C140.22067 (17)1.0308 (2)0.5271 (4)0.0191 (6)
H140.21570.98370.63710.023*
C150.17295 (17)1.0040 (2)0.3507 (4)0.0151 (5)
C160.11541 (17)0.9100 (2)0.3225 (3)0.0141 (5)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0135 (11)0.0131 (13)0.0211 (13)−0.0013 (10)0.0009 (11)−0.0021 (11)
O10.0202 (8)0.0147 (9)0.0144 (8)−0.0019 (8)−0.0021 (7)0.0019 (7)
C20.0232 (13)0.0180 (14)0.0210 (14)−0.0019 (11)0.0019 (12)0.0042 (12)
C30.0263 (14)0.0171 (14)0.0277 (14)−0.0048 (12)0.0018 (13)0.0035 (12)
C40.0197 (13)0.0213 (15)0.0286 (15)−0.0056 (12)−0.0006 (12)−0.0007 (13)
C50.0164 (12)0.0169 (14)0.0203 (13)−0.0010 (11)−0.0023 (11)−0.0023 (12)
C60.0126 (11)0.0128 (13)0.0159 (12)0.0037 (10)0.0024 (10)−0.0007 (11)
C70.0119 (12)0.0132 (13)0.0158 (12)0.0041 (10)0.0022 (11)−0.0027 (11)
C80.0185 (12)0.0172 (14)0.0140 (12)0.0036 (11)−0.0010 (11)−0.0012 (11)
C90.0200 (12)0.0174 (13)0.0186 (13)0.0036 (11)0.0040 (11)0.0030 (12)
C100.0127 (11)0.0153 (13)0.0233 (14)0.0024 (10)0.0046 (11)−0.0019 (12)
C110.0168 (13)0.0174 (15)0.0303 (15)0.0005 (11)0.0056 (13)0.0015 (13)
C120.0140 (12)0.0199 (15)0.0391 (17)−0.0041 (11)0.0037 (13)−0.0069 (14)
C130.0167 (12)0.0257 (16)0.0278 (15)−0.0006 (12)−0.0023 (12)−0.0106 (14)
C140.0149 (12)0.0209 (14)0.0216 (13)0.0012 (11)0.0002 (11)−0.0020 (13)
C150.0115 (11)0.0159 (13)0.0180 (12)0.0020 (10)0.0021 (10)−0.0026 (11)
C160.0155 (12)0.0117 (13)0.0152 (13)0.0035 (10)0.0039 (11)0.0003 (11)
Geometric parameters (Å, º) top
C1—C61.343 (3)C7—C161.383 (3)
C1—O11.388 (3)C7—C81.411 (3)
C1—C21.486 (3)C8—C91.371 (3)
O1—C161.377 (3)C8—H80.9500
C2—C31.532 (4)C9—C101.429 (4)
C2—H2A0.9900C9—H90.9500
C2—H2B0.9900C10—C111.414 (4)
C3—C41.534 (4)C10—C151.419 (3)
C3—H3A0.9900C11—C121.366 (4)
C3—H3B0.9900C11—H110.9500
C4—C51.528 (4)C12—C131.398 (4)
C4—H4A0.9900C12—H120.9500
C4—H4B0.9900C13—C141.377 (3)
C5—C61.494 (3)C13—H130.9500
C5—H5A0.9900C14—C151.415 (4)
C5—H5B0.9900C14—H140.9500
C6—C71.446 (3)C15—C161.411 (3)
C6—C1—O1112.4 (2)C16—C7—C8119.4 (2)
C6—C1—C2127.5 (2)C16—C7—C6105.6 (2)
O1—C1—C2120.1 (2)C8—C7—C6135.0 (2)
C16—O1—C1104.80 (18)C9—C8—C7118.6 (2)
C1—C2—C3107.9 (2)C9—C8—H8120.7
C1—C2—H2A110.1C7—C8—H8120.7
C3—C2—H2A110.1C8—C9—C10121.9 (2)
C1—C2—H2B110.1C8—C9—H9119.1
C3—C2—H2B110.1C10—C9—H9119.1
H2A—C2—H2B108.4C11—C10—C15118.0 (2)
C2—C3—C4111.7 (2)C11—C10—C9121.6 (2)
C2—C3—H3A109.3C15—C10—C9120.4 (2)
C4—C3—H3A109.3C12—C11—C10121.2 (3)
C2—C3—H3B109.3C12—C11—H11119.4
C4—C3—H3B109.3C10—C11—H11119.4
H3A—C3—H3B107.9C11—C12—C13120.4 (2)
C5—C4—C3112.0 (2)C11—C12—H12119.8
C5—C4—H4A109.2C13—C12—H12119.8
C3—C4—H4A109.2C14—C13—C12120.7 (3)
C5—C4—H4B109.2C14—C13—H13119.6
C3—C4—H4B109.2C12—C13—H13119.6
H4A—C4—H4B107.9C13—C14—C15119.6 (2)
C6—C5—C4109.7 (2)C13—C14—H14120.2
C6—C5—H5A109.7C15—C14—H14120.2
C4—C5—H5A109.7C16—C15—C14124.6 (2)
C6—C5—H5B109.7C16—C15—C10115.3 (2)
C4—C5—H5B109.7C14—C15—C10120.1 (2)
H5A—C5—H5B108.2O1—C16—C7111.1 (2)
C1—C6—C7106.1 (2)O1—C16—C15124.5 (2)
C1—C6—C5122.8 (2)C7—C16—C15124.4 (2)
C7—C6—C5131.1 (2)
C6—C1—O1—C160.3 (2)C15—C10—C11—C12−0.7 (4)
C2—C1—O1—C16−179.7 (2)C9—C10—C11—C12179.5 (2)
C6—C1—C2—C315.0 (3)C10—C11—C12—C130.1 (4)
O1—C1—C2—C3−165.0 (2)C11—C12—C13—C140.6 (4)
C1—C2—C3—C4−44.6 (3)C12—C13—C14—C15−0.6 (4)
C2—C3—C4—C563.3 (3)C13—C14—C15—C16−179.5 (2)
C3—C4—C5—C6−45.0 (3)C13—C14—C15—C10−0.1 (4)
O1—C1—C6—C7−0.5 (3)C11—C10—C15—C16−179.8 (2)
C2—C1—C6—C7179.5 (2)C9—C10—C15—C160.0 (3)
O1—C1—C6—C5−179.9 (2)C11—C10—C15—C140.7 (3)
C2—C1—C6—C50.0 (4)C9—C10—C15—C14−179.5 (2)
C4—C5—C6—C114.8 (3)C1—O1—C16—C70.0 (2)
C4—C5—C6—C7−164.5 (2)C1—O1—C16—C15179.4 (2)
C1—C6—C7—C160.4 (2)C8—C7—C16—O1179.21 (19)
C5—C6—C7—C16179.8 (2)C6—C7—C16—O1−0.2 (3)
C1—C6—C7—C8−178.9 (3)C8—C7—C16—C15−0.2 (3)
C5—C6—C7—C80.5 (4)C6—C7—C16—C15−179.6 (2)
C16—C7—C8—C9−0.9 (3)C14—C15—C16—O10.8 (4)
C6—C7—C8—C9178.4 (2)C10—C15—C16—O1−178.7 (2)
C7—C8—C9—C101.4 (3)C14—C15—C16—C7−179.9 (2)
C8—C9—C10—C11178.8 (2)C10—C15—C16—C70.6 (3)
C8—C9—C10—C15−1.0 (4)
Hydrogen-bond geometry (Å, º) top
Cg3 and Cg4 are the centroids of rings C7–C10/C15/C16 and C10–C15, respectively.
D—H···AD—HH···AD···AD—H···A
C5—H5B···Cg4i0.992.693.664 (3)167
C8—H8···Cg3i0.952.933.650 (3)134
Symmetry code: (i) −x, −y+2, z−1/2.
 

Acknowledgements

This work was supported by the Max–Plank Society, Germany.

References

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Journal logoCRYSTALLOGRAPHIC
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ISSN: 2056-9890
Volume 72| Part 1| January 2016| Pages 106-108
doi:10.1107/S2056989015024512
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