Microwave-assisted aliphatic fluorine–chlorine exchange using triethylamine trihydrofluoride (TREAT-HF)

Aliphatic fluorine–chlorine exchange reactions can be performed under microwave conditions using TREAT-HF as a mild and selective fluorination reagent. The highly polar TREAT-HF couples efficiently with microwave irradiation and reaction temperatures of 250 °C can be reached within 30 s. Under these conditions dichloromethyl- and trichloromethyl substrates can be converted into the corresponding fluoro analogs within 5 min. In order to prevent corrosion of borosilicate reaction vessel at high temperatures the use of sintered silicon carbide microwave vials is introduced.