Polymer chemistry. Part V. γ-Ray induced telomerisation reactions involving 1,1-difluoroethene and hexafluoropropene

The catalytic olefination reaction of aldehydes and ketones with CBr3CF3

“…Also it was applied in the synthesis of trifluoromethylpyrazoles [23] and in the telomerisation reaction with some fluorinated alkenes [24]. CBr 3 CF 3 was prepared by AlBr 3 promoted isomerisation of the commercially available CF 2 BrCF 2 Br [24]. We found that Halon TM CBr 3 CF 3 under catalysis of CuCl reacts with hydrazones of aldehydes and ketones 2 to form 2-bromo-3,3,3-trifluoroprop-1-enes 3 (Scheme 2).…”

“…Then freshly purified CuCl [29] (20 mg, 0.2 mmol) and aqueous ammonia (0.7 mL) were added. After 10 min a solution of CBr 3 CF 3 (was prepared by AlBr 3 promoted isomerisation of the commercially available CF 2 BrCF 2 Br [24]) (1.93 g, 6 mmol) in DMSO (2 mL) was added dropwise, maintaining the temperature at 20 8C (water bath). The reaction mixture was stirred for 24 h and quenched with hydrochloric acid (5%) (100 mL).…”

Polyfluorinated Ethanes as Versatile Fluorinated C2-Building Blocks for Organic Synthesis

“…Using this approach, both CF 3 CBr 3 and CF 3 CFBr 2 were obtained efficiently via the isomerization of BrCF 2 CF 2 Br under the corresponding reaction conditions. AlCl 3 as well as AlBr 3 were used as catalysts for the isomerization. It should be noted that AlBr 3 was shown to be more effective, providing higher yields by a lesser amount of the catalyst (Scheme ).…”