The ¹⁹F NMR spectrum of cis‐1,2‐dichlorohexafluorocyclobutane

Structural Assignment of Fluorocyclobutenes by 19F NMR Spectroscopy – Comparison of Calculated 19F NMR Shielding Constants with Experimental 19F NMR Shifts

“…54–59 °C. The 19 F NMR spectrum of the product corresponded to the literature data . cis ‐1,2‐Dichloro‐1,2,3,3,4,4‐hexafluorocyclobutane: 19 F NMR (282.23 MHz, CDCl 3 ): δ = –117.9 (dm, 2 J F,F = 218 Hz, 2 F, F CF– F CF), –129.9 (dm, 2 J F,F = 218 Hz, 2 F, FC F– FC F ), –137.2 (m, 2 F, C F Cl–C F Cl) ppm.…”

“…The 19 F NMR spectrum of the product corresponded to the literature data. [39] cis-1,2- Dichloro-1,2,3,3,4,4-hexafluorocyclobutane: 19 F NMR (282.23 MHz, CDCl 3 ): δ = -117.9 (dm, 2 J F,F = 218 Hz, 2 F, FCF-FCF), -129.9 (dm, 2 J F,F = 218 Hz, 2 F, FCF-FCF), -137.2 (m, 2 F, CFCl-CFCl) ppm. trans-1,2-Dichloro-1,2,3,3,4,4-hexafluorocyclobutane: 19 F NMR (282.23 MHz, CDCl 3 ): δ = -121.8 (dm, 2 J F,F = 213 Hz, 2 F, FCF-FCF), -125.7 (dm, 2 J F,F = 213 Hz, 2 F, FCF-FCF), -127.7 (m, 2 F, CFCl-CFCl) ppm.…”

Bimolecular Kinetic Studies with High-Temperature Gas-Phase 19F NMR: Cycloaddition Reactions of Fluoroolefins

“…The three major resonances with partially resolved spin−spin coupling for the three vinylic fluorines agree well with published data in solution. In this case, rather exceptionally, the NMR spectrum was also studied in the gas phase to provide information on the 19 F nuclear magnetic shielding for the three different vinylic environments in CTFE. , Already quite visible are the narrower lines belonging to a 1:1 mixture of cis - and trans -1,2-dichlorohexafluorocyclobutane whose solution spectra have also been studied before. 11a, These lines grow at the expense of the CTFE resonances, as can be seen graphically by viewing the set of spectra obtained automatically according to a prearranged time schedule. A spectrum near the end of the reaction is shown in Figure (bottom).…”