“…On the other hand, many fluorinated 6-membered heteroaromatic derivatives find applications in a wide variety of drugs and plant protective materials and, consequently, there are several examples of the synthesis of fluorinated 6-membered heteroaromatic rings by selective fluorination strategies. [15][16][17][18][19][20][21][22][23][24][25][26][27] However, selective fluorination of 5membered heteroaromatic systems are rare and, in particular, there are only a few reports concerning the synthesis of fluorinated 5-membered heteroaromatic systems that have two heteroatoms, such as pyrazoles [28,29], isoxaoles [30] and thiazoles [31,32]. We recently reported selective fluorination of isoxazoles to give mono-fluorinated isoxazoles (3) or tri-fluorinated isoxazolines (4) in moderate to good yields (Scheme 1).…”