一种新型的芳基重排反应（Ⅱ）──苯并环己酮中β－芳基的重排

A Novel Aryl Rearrangement Reaction(Ⅱ) ──β-Aryl Rearrangement in the Tetral-1-ones

报道了３－芳基四氢合萘－１－酮的烯醇硅醚在氧化碘苯－三氟化硼的协同作用下３－位芳基迁移到２－位，生成２－芳基－３－氟四氢合萘－１－酮的反应。当芳基是Ｐｈ－ｐ－Ｃｌ－Ｐｈ、ｐ－Ｍｅ－Ｐｈ和ｐ－ＭｅＯ－Ｐｈ时，收率分别为８０％、６１％、１０％和５％，并讨论了这一反应的机理。

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·BF_3). 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.