Abstract: The aryl group of 3-aryltetral-1-ones was shifted to position-2 yielding 2-aryl-3-fluorotetral-1-ones when the enol silyl ethers derived from the 3-aryltetral^-1-ones were treated with iodosobenzene- borontrifluoride complex(PhIO·BF₃).As the aryl was Ph-,p-Cl-Ph-, p-Me-Ph-, and p-MeO-Ph-, the yields of the products was 80%, 61%, 10% and 5% respectively.The rearrangement mechanism was suggested to be a successive process.the end silyl ether 2 reacts with PhIO·BF₃ to form an intermediate 6.3-Aryl group has a backside migration to C-2which is deficient in electron as iodine atom departs from it, and the fluorine atom attakcts C-3while the heterolysis of fluorine-boron bond is completed.

Key words: Tetral-1-one, Enol silyl ether, Aryl rearrangement, Iodosobenzene-borontrifluoride