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

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12,15-Di­methyl-8-oxa­tetra­cyclo­[8.8.0.02,7.011,16]octa­deca-1(18),2,4,6,11(16),12,14-heptaen-10-ol

CROSSMARK_Color_square_no_text.svg

aDepartment of Chemistry, University of Toronto, Toronto, Ontario, M5S 3H6, Canada, and bDepartment of Chemistry, University of Guelph, Guelph, Ontario, N1G 2W1, Canada
*Correspondence e-mail: alan.lough@utoronto.ca

Edited by W. T. A. Harrison, University of Aberdeen, Scotland (Received 2 March 2020; accepted 6 March 2020; online 10 March 2020)

In the title compound, C19H18O2, the pyran ring is in a half-chair conformation. The fused ring system comprising the benzene and cyclo­hexene rings is essentially planar (r.m.s. deviation = 0.053 Å) and forms a dihedral angle of 27.95 (6)° with the other benzene ring. In the crystal, O—H⋯O hydrogen bonds connect the mol­ecules into chains propagating along [001].

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

Structure description

The ring-opening reaction of oxabenzonorbornadiene (OBD) has been well studied by many groups including our own (Lautens et al., 2003[Lautens, M., Fagnou, K. & Hiebert, S. (2003). Acc. Chem. Res. 36, 48-58.]; Rayabarapu & Cheng, 2007[Rayabarapu, D. K. & Cheng, C.-H. (2007). Acc. Chem. Res. 40, 971-983.]; Boutin et al., 2019[Boutin, R., Koh, S. & Tam, W. (2019). Curr. Org. Synth. 16, 460-484.]; Hill et al., 2019[Hill, J., Wicks, C., Pounder, A. & Tam, W. (2019). Tetrahedron Lett. 60, 150990.]; Hill & Tam, 2019[Hill, J. & Tam, W. (2019). J. Org. Chem. 84, 8309-8314.]). Building on the work of Cheng (Duan & Cheng, 1995[Duan, J. & Cheng, C. H. (1995). Organometallics, 14, 1608-1618.]), our group has also demonstrated the palladium-catalysed regioselective ring-opening of C1-substituted OBDs using aryl iodides (Raheem et al., 2014[Raheem, M. A., Edmunds, M. & Tam, W. (2014). Can. J. Chem. 92, 888-895.]). However, to the best of our knowledge, intra­molecular modes of this reactivity have been left unexplored. Currently, the only known intra­molecular transformation of OBD was reported by the Lautens group (Loh et al., 2016[Loh, C. C. J., Schmid, M., Webster, R., Yen, A., Yazdi, S. K., Franke, P. T. & Lautens, M. (2016). Angew. Chem. Int. Ed. 55, 10074-10078.]) with a similar transformation recently reported by our group on cyclo­propanated OBD (Wicks et al., 2019[Wicks, C., Koh, S., Pounder, A., Carlson, E. & Tam, W. (2019). Tetrahedron Lett. 60, 151228.]). Based on this, we set out to investigate palladium-catalysed intra­molecular ring-openings of OBD with C1-tethered aryl halides. The reaction of C1-substituted OBD I (see Fig. 1[link]) in the presence of PdCl2(PPh3)2, Zn, Et3N, and MeCN afforded an expected dehydrated product II in 82% yield, as well as an unexpected and yet unreported hydrated product III in 14% yield. The structure of the alcohol-containing fused tetra­cycle III was confirmed by single-crystal X-ray analysis.

[Figure 1]
Figure 1
The reaction scheme

The mol­ecular structure of the title compound is shown in Fig. 2[link]. The pyran ring (O1/C1/C2/C11/C12/C17) is in a half-chair conformation with atoms C1 and C2 deviating from the mean-plane of the other four atoms by −0.197 (2) and 0.556 (1) Å, respectively. The fused ring system comprising the benzene (C3–C8) and cyclo­hexene (C2/C3/C8–C11) rings is essentially planar (r.m.s. deviation = 0.053 Å) and forms a dihedral angle of 27.95 (6)° with the other benzene ring (C12–C17). In the arbitrarily chosen asymmetric unit, atom C2 has an S configuration but crystal symmetry generates a racemic mixture. In the crystal, O—H⋯O hydrogen bonds (Table 1[link]) connect the mol­ecules into chains propagating along [001] (Fig. 3[link]).

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O2—H2O⋯O1i 0.86 (2) 2.03 (2) 2.8805 (14) 171.0 (19)
Symmetry code: (i) [x, -y+{\script{3\over 2}}, z-{\script{1\over 2}}].
[Figure 2]
Figure 2
The mol­ecular structure of the title compound with displacement ellipsoids drawn at the 30% probability level.
[Figure 3]
Figure 3
Part of the crystal structure with O—H⋯O hydrogen bonds shown as dashed lines.

Synthesis and crystallization

To a 2 dram vial was added oxabenzonorbornadiene I (Fig. 1[link]) (67.8 mg, 0.168 mmol), then purged with argon before importing into a glove box under an inert argon atmosphere. The vial was loaded sequentially with Zn (123.3 mg, 1.89 mmol, 11.2 eq.), MeCN (1.5 ml), Et3N (0.09 ml, 0.669 mmol, 0.25 eq.) and PdCl2(PPh3)2 (12.5 mg, 0.0178 mmol, 10.6 mol%), then exported and stirred at 333 K for 1 day. The mixture was cooled to room temperature and stirred in air for 10 minutes before removing the solvent under reduced pressure. The crude mixture was then purified by flash column chromatography using gradient elution (EtOAc:hexa­nes 1:9 to EtOAc:hexa­nes 1:4) to obtain the ring-opened product II (35.8 mg, 82%) as a white solid and III (6.6 mg, 14%) as a white solid. The product III was subsequently crystallized from methyl­ene chloride solution by slow evaporation to give product III as colourless crystals with orange specks.

Refinement

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

Table 2
Experimental details

Crystal data
Chemical formula C19H18O2
Mr 278.33
Crystal system, space group Monoclinic, P21/c
Temperature (K) 150
a, b, c (Å) 12.2712 (7), 11.2934 (6), 10.8984 (7)
β (°) 112.565 (2)
V3) 1394.71 (14)
Z 4
Radiation type Mo Kα
μ (mm−1) 0.09
Crystal size (mm) 0.25 × 0.19 × 0.11
 
Data collection
Diffractometer Bruker Kappa APEX DUO CCD
Absorption correction Multi-scan (SADABS; Krause et al., 2015[Krause, L., Herbst-Irmer, R., Sheldrick, G. M. & Stalke, D. (2015). J. Appl. Cryst. 48, 3-10.])
Tmin, Tmax 0.703, 0.746
No. of measured, independent and observed [I > 2σ(I)] reflections 22859, 3212, 2404
Rint 0.040
(sin θ/λ)max−1) 0.650
 
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.040, 0.110, 1.04
No. of reflections 3212
No. of parameters 196
H-atom treatment H atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å−3) 0.31, −0.22
Computer programs: APEX3 (Bruker, 2018[Bruker (2018). APEX3 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]), SAINT (Bruker, 2018[Bruker (2018). APEX3 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]), SHELXT2014 (Sheldrick, 2015a[Sheldrick, G. M. (2015a). Acta Cryst. A71, 3-8.]), SHELXL2018 (Sheldrick, 2015b[Sheldrick, G. M. (2015b). Acta Cryst. C71, 3-8.]), PLATON (Spek, 2020[Spek, A. L. (2020). Acta Cryst. E76, 1-11.]), publCIF (Westrip, 2010[Westrip, S. P. (2010). J. Appl. Cryst. 43, 920-925.]).

Structural data


Computing details top

Data collection: APEX3 (Bruker, 2018); cell refinement: APEX3 (Bruker, 2018); data reduction: SAINT (Bruker, 2018); program(s) used to solve structure: SHELXT2014 (Sheldrick, 2015a); program(s) used to refine structure: SHELXL2018 (Sheldrick, 2015b); molecular graphics: PLATON (Spek, 2020); software used to prepare material for publication: publCIF (Westrip, 2010).

12,15-Dimethyl-8-oxatetracyclo[8.8.0.02,7.011,16]octadeca-1(18),2,4,6,11(16),12,14-heptaen-10-ol top
Crystal data top
C19H18O2F(000) = 592
Mr = 278.33Dx = 1.326 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
a = 12.2712 (7) ÅCell parameters from 6674 reflections
b = 11.2934 (6) Åθ = 2.6–27.5°
c = 10.8984 (7) ŵ = 0.09 mm1
β = 112.565 (2)°T = 150 K
V = 1394.71 (14) Å3Shard, colourless
Z = 40.25 × 0.19 × 0.11 mm
Data collection top
Bruker Kappa APEX DUO CCD
diffractometer
2404 reflections with I > 2σ(I)
Radiation source: sealed tube with Bruker Triumph monochromatorRint = 0.040
φ and ω scansθmax = 27.5°, θmin = 1.8°
Absorption correction: multi-scan
(SADABS; Krause et al., 2015)
h = 1515
Tmin = 0.703, Tmax = 0.746k = 1412
22859 measured reflectionsl = 1414
3212 independent reflections
Refinement top
Refinement on F2Primary atom site location: dual
Least-squares matrix: fullHydrogen site location: mixed
R[F2 > 2σ(F2)] = 0.040H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.110 w = 1/[σ2(Fo2) + (0.0478P)2 + 0.6316P]
where P = (Fo2 + 2Fc2)/3
S = 1.03(Δ/σ)max < 0.001
3212 reflectionsΔρmax = 0.31 e Å3
196 parametersΔρmin = 0.21 e Å3
0 restraints
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
O10.38362 (9)0.71483 (9)0.94095 (10)0.0227 (2)
O20.35317 (9)0.79851 (9)0.68983 (10)0.0195 (2)
H2O0.3639 (17)0.8028 (17)0.616 (2)0.041 (6)*
C10.28530 (12)0.67697 (13)0.82436 (13)0.0194 (3)
H1A0.2168560.7290790.8112910.023*
H1B0.2630280.5953360.8383780.023*
C20.31342 (12)0.67990 (12)0.69883 (13)0.0165 (3)
C30.20305 (12)0.64875 (12)0.57662 (13)0.0168 (3)
C40.10115 (12)0.72098 (12)0.54010 (14)0.0183 (3)
C50.00046 (13)0.68454 (13)0.43491 (14)0.0207 (3)
H5A0.0701860.7308040.4114310.025*
C60.00220 (13)0.58267 (13)0.36392 (14)0.0217 (3)
H6A0.0736190.5585600.2948640.026*
C70.09851 (13)0.51547 (13)0.39205 (14)0.0204 (3)
C80.20197 (12)0.54850 (12)0.49950 (14)0.0185 (3)
C90.31027 (13)0.47357 (14)0.52591 (15)0.0266 (3)
H9A0.2893570.3898430.5327010.032*
H9B0.3333080.4799370.4484910.032*
C100.41426 (13)0.50446 (14)0.64767 (15)0.0230 (3)
H10A0.4829180.4566040.6707660.028*
C110.41632 (12)0.59543 (12)0.72595 (13)0.0182 (3)
C120.51602 (12)0.61900 (12)0.85341 (14)0.0188 (3)
C130.63234 (13)0.58519 (13)0.87853 (15)0.0235 (3)
H13A0.6497730.5471250.8104680.028*
C140.72254 (13)0.60601 (14)1.00035 (16)0.0266 (3)
H14A0.8009380.5823021.0155310.032*
C150.69775 (13)0.66181 (14)1.10041 (16)0.0258 (3)
H15A0.7593370.6753891.1844650.031*
C160.58418 (13)0.69762 (13)1.07837 (15)0.0231 (3)
H16A0.5675550.7365841.1464790.028*
C170.49430 (12)0.67609 (13)0.95542 (14)0.0192 (3)
C180.09345 (14)0.83818 (14)0.60380 (16)0.0255 (3)
H18A0.1724680.8727900.6449210.038*
H18B0.0607720.8253420.6718710.038*
H18C0.0421110.8922640.5358370.038*
C190.09555 (14)0.40895 (14)0.30771 (15)0.0271 (3)
H19A0.1545200.4183300.2681380.041*
H19B0.0169480.4016180.2370100.041*
H19C0.1132420.3375810.3630800.041*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0194 (5)0.0335 (6)0.0143 (5)0.0017 (4)0.0056 (4)0.0035 (4)
O20.0245 (5)0.0175 (5)0.0182 (5)0.0023 (4)0.0100 (4)0.0002 (4)
C10.0176 (7)0.0263 (8)0.0140 (7)0.0015 (6)0.0059 (5)0.0003 (5)
C20.0197 (7)0.0162 (7)0.0141 (6)0.0010 (5)0.0071 (5)0.0006 (5)
C30.0191 (7)0.0186 (7)0.0136 (6)0.0012 (5)0.0073 (5)0.0013 (5)
C40.0223 (7)0.0181 (7)0.0162 (7)0.0000 (6)0.0091 (6)0.0019 (5)
C50.0203 (7)0.0231 (8)0.0182 (7)0.0023 (6)0.0068 (6)0.0035 (6)
C60.0220 (7)0.0255 (8)0.0146 (7)0.0036 (6)0.0036 (6)0.0013 (6)
C70.0264 (7)0.0195 (7)0.0155 (7)0.0032 (6)0.0083 (6)0.0001 (5)
C80.0223 (7)0.0183 (7)0.0160 (7)0.0010 (5)0.0085 (6)0.0000 (5)
C90.0279 (8)0.0252 (8)0.0239 (8)0.0039 (6)0.0068 (6)0.0078 (6)
C100.0225 (7)0.0247 (8)0.0214 (7)0.0041 (6)0.0079 (6)0.0007 (6)
C110.0192 (7)0.0202 (7)0.0159 (7)0.0005 (5)0.0076 (5)0.0024 (5)
C120.0206 (7)0.0179 (7)0.0176 (7)0.0003 (6)0.0071 (6)0.0021 (5)
C130.0231 (7)0.0234 (8)0.0243 (8)0.0018 (6)0.0094 (6)0.0022 (6)
C140.0194 (7)0.0278 (8)0.0298 (8)0.0025 (6)0.0065 (6)0.0041 (7)
C150.0229 (8)0.0256 (8)0.0221 (8)0.0028 (6)0.0010 (6)0.0033 (6)
C160.0263 (8)0.0242 (8)0.0177 (7)0.0018 (6)0.0073 (6)0.0003 (6)
C170.0189 (7)0.0203 (7)0.0180 (7)0.0001 (5)0.0064 (6)0.0032 (6)
C180.0250 (8)0.0242 (8)0.0245 (8)0.0053 (6)0.0063 (6)0.0030 (6)
C190.0320 (9)0.0247 (8)0.0215 (8)0.0029 (6)0.0070 (6)0.0061 (6)
Geometric parameters (Å, º) top
O1—C171.3771 (17)C9—H9A0.9900
O1—C11.4410 (17)C9—H9B0.9900
O2—C21.4417 (17)C10—C111.329 (2)
O2—H2O0.86 (2)C10—H10A0.9500
C1—C21.5343 (18)C11—C121.4809 (19)
C1—H1A0.9900C12—C171.397 (2)
C1—H1B0.9900C12—C131.399 (2)
C2—C111.5184 (19)C13—C141.384 (2)
C2—C31.5322 (19)C13—H13A0.9500
C3—C81.4071 (19)C14—C151.390 (2)
C3—C41.4162 (19)C14—H14A0.9500
C4—C51.393 (2)C15—C161.381 (2)
C4—C181.514 (2)C15—H15A0.9500
C5—C61.382 (2)C16—C171.392 (2)
C5—H5A0.9500C16—H16A0.9500
C6—C71.381 (2)C18—H18A0.9800
C6—H6A0.9500C18—H18B0.9800
C7—C81.408 (2)C18—H18C0.9800
C7—C191.506 (2)C19—H19A0.9800
C8—C91.507 (2)C19—H19B0.9800
C9—C101.487 (2)C19—H19C0.9800
C17—O1—C1117.52 (11)H9A—C9—H9B107.5
C2—O2—H2O107.0 (13)C11—C10—C9123.53 (14)
O1—C1—C2112.41 (11)C11—C10—H10A118.2
O1—C1—H1A109.1C9—C10—H10A118.2
C2—C1—H1A109.1C10—C11—C12123.11 (13)
O1—C1—H1B109.1C10—C11—C2123.44 (13)
C2—C1—H1B109.1C12—C11—C2113.31 (12)
H1A—C1—H1B107.9C17—C12—C13117.53 (13)
O2—C2—C11108.61 (11)C17—C12—C11119.23 (12)
O2—C2—C3111.32 (11)C13—C12—C11123.23 (13)
C11—C2—C3114.62 (11)C14—C13—C12121.44 (14)
O2—C2—C1106.17 (11)C14—C13—H13A119.3
C11—C2—C1105.53 (11)C12—C13—H13A119.3
C3—C2—C1110.11 (11)C13—C14—C15119.62 (14)
C8—C3—C4119.39 (13)C13—C14—H14A120.2
C8—C3—C2120.44 (12)C15—C14—H14A120.2
C4—C3—C2120.18 (12)C16—C15—C14120.41 (14)
C5—C4—C3118.42 (13)C16—C15—H15A119.8
C5—C4—C18116.22 (13)C14—C15—H15A119.8
C3—C4—C18125.34 (13)C15—C16—C17119.37 (14)
C6—C5—C4121.55 (13)C15—C16—H16A120.3
C6—C5—H5A119.2C17—C16—H16A120.3
C4—C5—H5A119.2O1—C17—C16115.93 (13)
C7—C6—C5120.87 (13)O1—C17—C12122.45 (12)
C7—C6—H6A119.6C16—C17—C12121.62 (13)
C5—C6—H6A119.6C4—C18—H18A109.5
C6—C7—C8118.93 (13)C4—C18—H18B109.5
C6—C7—C19119.58 (13)H18A—C18—H18B109.5
C8—C7—C19121.49 (13)C4—C18—H18C109.5
C3—C8—C7120.59 (13)H18A—C18—H18C109.5
C3—C8—C9122.15 (13)H18B—C18—H18C109.5
C7—C8—C9117.25 (13)C7—C19—H19A109.5
C10—C9—C8115.51 (12)C7—C19—H19B109.5
C10—C9—H9A108.4H19A—C19—H19B109.5
C8—C9—H9A108.4C7—C19—H19C109.5
C10—C9—H9B108.4H19A—C19—H19C109.5
C8—C9—H9B108.4H19B—C19—H19C109.5
C17—O1—C1—C241.25 (17)C7—C8—C9—C10174.41 (13)
O1—C1—C2—O254.75 (14)C8—C9—C10—C113.5 (2)
O1—C1—C2—C1160.43 (14)C9—C10—C11—C12174.19 (14)
O1—C1—C2—C3175.37 (11)C9—C10—C11—C21.2 (2)
O2—C2—C3—C8123.95 (13)O2—C2—C11—C10122.26 (14)
C11—C2—C3—C80.19 (18)C3—C2—C11—C102.93 (19)
C1—C2—C3—C8118.58 (14)C1—C2—C11—C10124.26 (15)
O2—C2—C3—C455.88 (16)O2—C2—C11—C1261.99 (14)
C11—C2—C3—C4179.64 (11)C3—C2—C11—C12172.82 (11)
C1—C2—C3—C461.59 (16)C1—C2—C11—C1251.50 (14)
C8—C3—C4—C55.28 (19)C10—C11—C12—C17150.86 (15)
C2—C3—C4—C5174.89 (12)C2—C11—C12—C1724.91 (18)
C8—C3—C4—C18172.91 (13)C10—C11—C12—C1328.1 (2)
C2—C3—C4—C186.9 (2)C2—C11—C12—C13156.10 (13)
C3—C4—C5—C62.2 (2)C17—C12—C13—C140.8 (2)
C18—C4—C5—C6176.20 (13)C11—C12—C13—C14178.20 (14)
C4—C5—C6—C72.3 (2)C12—C13—C14—C150.1 (2)
C5—C6—C7—C83.6 (2)C13—C14—C15—C160.7 (2)
C5—C6—C7—C19176.41 (13)C14—C15—C16—C170.8 (2)
C4—C3—C8—C74.1 (2)C1—O1—C17—C16169.75 (12)
C2—C3—C8—C7176.07 (12)C1—O1—C17—C1210.5 (2)
C4—C3—C8—C9174.87 (13)C15—C16—C17—O1179.75 (13)
C2—C3—C8—C95.0 (2)C15—C16—C17—C120.0 (2)
C6—C7—C8—C30.3 (2)C13—C12—C17—O1178.97 (13)
C19—C7—C8—C3179.64 (13)C11—C12—C17—O12.0 (2)
C6—C7—C8—C9179.36 (13)C13—C12—C17—C160.8 (2)
C19—C7—C8—C90.6 (2)C11—C12—C17—C16178.27 (13)
C3—C8—C9—C106.6 (2)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O2—H2O···O1i0.86 (2)2.03 (2)2.8805 (14)171.0 (19)
Symmetry code: (i) x, y+3/2, z1/2.
 

Acknowledgements

The University of Toronto thanks NSERC Canada for funding.

References

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