Simple synthesis of multi-halogenated alkenes from 2-bromo-2-chloro-1,1,1-trifluoroethane (halothane)

• Yukiko Karuo,
• Atsushi Tarui,
• Kazuyuki Sato,
• Kentaro Kawai and
• Masaaki Omote

Beilstein J. Org. Chem. 2022, 18, 1567–1574, doi:10.3762/bjoc.18.167

• fluorine atoms were prepared in moderate to good yields via the reactions of phenols and 2-bromo-2-chloro-1,1,1-trifluoroethane (halothane) in the presence of KOH. This simple reaction enabled the construction of highly halogenated compounds with the potential for further functionalization. The reaction

• involved a highly reactive difluoroethylene intermediate, which was produced by the reaction between halothane and KOH. Keywords: aryl 1-monofluorovinyl ether; electrophilic 1,1-difluoroethene; halothane; multi-halogenated alkene; phenol; Introduction 2-Bromo-2-chloro-1,1,1-trifluoroethane (halothane

• ) has been used as a fluorine-containing building block for the construction of trifluoromethyl and difluoromethylene motifs [1][2]. Such structures have been found in several multifunctional materials and biologically important molecules (Figure 1) [3][4][5][6][7]. The halothane structure contains two

Synthesis of aryl 2-bromo-2-chloro-1,1-difluoroethyl ethers through the base-mediated reaction between phenols and halothane

• Yukiko Karuo,
• Ayaka Kametani,
• Atsushi Tarui,
• Kazuyuki Sato,
• Kentaro Kawai and
• Masaaki Omote

Beilstein J. Org. Chem. 2021, 17, 89–96, doi:10.3762/bjoc.17.9

• utility of halothane for the synthesis of aryl gem-difluoroalkyl ethers containing the bromochloromethyl group. Keywords: aryl 1,1-difluoroethyl ether; 1,1-difluoroethene; fluorine compound; halothane; phenol; Introduction Molecules containing fluoroalkyl groups are of interest in pharmaceutical and

• focused on halothane, 2-bromo-2-chloro-1,1,1-trifluoroethane, because the treatment of this compound with several bases was found to provide the highly electrophilic 2-bromo-2-chloro-1,1-difluoroethene [42][43]. Additionally, another report discussed the carbocationic character of the gem-difluorovinyl

• carbon that was explained by an orbital interaction between the n orbital (fluorine) and the π orbital [44]. A literature survey revealed that Yagupol’skii et al. have achieved the first synthesis of aryl or alkyl 2-bromo-2-chloro-1,1-difluoroethyl ethers by the reaction of alcohols with halothane as

Synthesis of uniform cyclodextrin thioethers to transport hydrophobic drugs

• Lisa F. Becker,
• Dennis H. Schwarz and
• Gerhard Wenz

Beilstein J. Org. Chem. 2014, 10, 2920–2927, doi:10.3762/bjoc.10.310

• the β-cyclodextrin derivatives exhibit very high binding potentials towards the anaesthetic drugs sevoflurane and halothane. Since the resulting inclusion compounds are highly soluble in water at temperatures ≤37 °C they are good candidates for new aqueous dosage forms which would avoid inhalation

• for the delivery of sevoflurane. Potentially oral aqueous dosage forms can be developed for both anaesthesia and the treatment of pain. 3b1 is also able to complex other hydrofluoric anaesthetics, like halothane [54], where the binding constant K = 9090 L/mol (occupancy of the host 98%) was even

• higher than for sevoflurane. Conclusion The water-soluble β-CD thioether 3b1 with the smallest possible substituents at both the sides of the CD torus showed the highest binding affinities for the anaesthetic APIs sevoflurane and halothane, much higher than native CDs and known CD derivatives. Since the