4-disubstituted tert-butyldimethylsilyl but-1-en-3-yn-1-yl ethers with Selectfluor gives 2-mono-fluorobut-3-yn-1-ones. Subsequent 5-endo-dig cyclization in the presence of chlorotriphenylphosphine gold(I)/silver trifluoromethanesulfonate (both 5 mol%, dichloromethane) under ambient conditions, provides a facile method for the generation of mainly 2,5-diaryl-substituted 3-fluorofurans in high yields
用Selectfluor
氟化1,4-二取代的叔丁基二甲基甲
硅烷基丁基-1-en-3-yn-1-基醚,得到2-单
氟丁基-3-yn-1- one 。在环境条件下,随后在
氯三苯基膦金(I)/
三氟甲磺酸银(均为5 mol%,
二氯甲烷)存在下进行的5-内挖-环化,提供了一种简便的方法来生成主要被2,5-二芳基取代的3-
氟呋喃高产(89-96%)。通过X射线晶体学确认2-(4-
溴苯基)-3-
氟-5-(4-甲基苯基)
呋喃的结构。