Alvino EL, et al. Journal of Fluorine Chemistry, 2020, 232, 109454.
Chemoselective nucleophilic addition reactions using perfluorocyclopentene (PFCP) have led to the synthesis of a number of novel fluorinated molecules. These compounds are prepared under relatively mild conditions, require little further purification and are produced in high yields.
PFCP can be used to obtain fluorinated molecules and materials by simultaneous nucleophilic addition of fluoroolefins at the 1-position and 5-position. Symmetric fluorinated compounds can be obtained by employing strong reaction conditions, e.g. using heat or strong bases. The addition is controlled chemoselectively to achieve substitution at the 1-position only, using less forced reaction conditions.
Fluorinated compounds in which the nucleophilic reagent is added to the fluoroolefin only once to produce a monosubstituted compound can be obtained under mild reaction conditions using route 2. (Compounds 1-8).
Their general synthesis is as follows:
Dimethylformamide (DMF), trimethylamine (TEA), and an excess of PFCP were charged into a 50 mL round bottom flask. The reaction was stirred at room temperature for 2-3 min and finally, the corresponding nucleophilic reagents were added. For compounds 1-6, GC-MS was performed after 30 minutes to verify complete conversion to the desired product. For compounds 7 and 8, the reaction was monitored by 19F NMR and was completed after 16 hours. The solution was washed with brine and the organics were extracted with ether. The ether was dried with magnesium sulfate and filtered under a vacuum. All volatiles were removed from the filtrate using a rotary evaporator. No further purification is required unless otherwise stated.
