Avance 3 400 nmr spectrometer

Semifluoroalkoxy-substituted fluorinated tolanes, 1 and 2, were synthesized according to the scheme shown in Figure 3. The reaction progress was confirmed using thin-layer chromatography (TLC), which was performed on silica gel TLC plates (silica gel 60254, Merck, Rahway, NJ, USA). The tolanes were purified by column chromatography using Wakogel^® 60N (38–100 mm). Melting and clearing temperatures of the molecules 1 and 2 were determined using DSC. ¹H and ¹³C-NMR spectra for 1 and 2 were recorded using a Bruker AVANCE III 400 NMR spectrometer (¹H: 400 MHz and ¹³C: 100 MHz) in chloroform-d (CDCl₃), and the chemical shifts were reported in parts per million (ppm) using the residual proton in the NMR solvent. ¹⁹F-NMR (376 MHz) spectra were obtained using a Bruker AVANCE III 400 NMR spectrometer in CDCl₃, and trichlorofluoromethane (CFCl₃, d_F = 0 ppm) or hexafluorobenzene (C₆F₆, d_F = −163 ppm) was used as an internal standard. Infrared (IR) spectra were recorded using the KBr method with a JASCO FT/IR-4100 type A spectrometer, and all spectra were reported in wavenumber (cm⁻¹). High-resolution mass spectrometry (HRMS) was performed on a JEOL JMS-700MS spectrometer using the fast atom bombardment (FAB) method.

The ¹H-NMR (400 MHz) and ¹³C-NMR (100 MHz) spectra were obtained using an AVANCE III 400 NMR spectrometer (Bruker, Rheinstetten, Germany) in chloroform-d (CDCl₃) solution, and the chemical shifts are reported in parts per million (ppm) using the residual protons in the NMR solvent. The ¹⁹F-NMR (376 MHz) spectra were obtained using an AVANCE III 400 NMR spectrometer (Bruker, Rheinstetten, Germany) in CDCl₃ solution with CFCl₃ (δ_F = 0 ppm) as an internal standard. Infrared (IR) spectra were recorded using the KBr method with an FTIR-4100 type A spectrometer (JASCO, Tokyo, Japan). All the spectra are reported in terms of wavenumber (cm^–1). High-resolution mass spectra (HRMS) were recorded on a JMS700MS spectrometer (JEOL, Tokyo, Japan) using the fast atom bombardment (FAB) method. All the chemicals, including solvents, were of reagent grade and were purified in the usual manner prior to use. Column chromatography was carried out on silica gel (FUJIFILM Wako Pure Chemical Corporation, Wakogel^® 60 N, 38–100 μm) and thin-layer chromatography (TLC) was performed on silica gel TLC plates (Merck, Silica gel 60F₂₅₄; Kenilworth, NJ, USA).

Maleic anhydride-β-cyclodextrin (MA-β-CD; Scheme 1) was synthesized following a previously described method [36 (link),37 (link)]. Briefly, β-CD (5.71 g) and MA (4.90 g) were dissolved in 30 mL of dry DMF and stirred for 12 h at 80 °C in a round bottom flask, under a N₂ atmosphere. The reaction was cooled to room temperature, and the product was precipitated with chloroform. The resulting beige solid (MA-β-CD) was obtained in 73% yield.
The proton nuclear magnetic resonance (¹H NMR) spectrum of MA-β-CD was recorded on Bruker Avance III 400 NMR spectrometer (Billerica, MA, USA) by the dissolution of the samples in deuterium oxide (D₂O, isotope substitution > 99.9% from Eurisotop, Cambridge, UK) and using ((3-(trimethylsilyl)-2,2′,3,3′-tetradeuteriopropionic acid), EurisoTop, as an internal reference.

¹H NMR (nuclear magnetic resonance) data were acquired on a Bruker Avance III 400 NMR spectrometer operating at 400.15 MHz. The relaxation delay was 90° pulse, a spectral width of 8012 Hz, and 65 K data points. ¹H NMR spectra of the samples were recorded at room temperature (25 ± 3 °C) in 5-mm outer diameter tubes. The samples were prepared in deuterated water. TMSP-d4 (3-(trimethylsilyl) propionic-2,2,3,3-d4 acid sodium salt) was used as the internal reference.