Lead tetraacetate (LTA) can smoothly induce the addition reaction of difluorodiiodomethane (1) with electron-rich alkenes at 60°C in diglyme to give monoadducts (RCHICH2CF2I) and diadducts (RCHICH2)2. The similar, clean reaction of fluoroolefins, such as tetrafluoroethene, hexafluoropropene, with 1 occurs only in acetic acid. However, non-fluorinated β-iodo-α,β-unsaturated carboxylic esters are obtained when 1 reacts with alkynes in alcohol. The iododifluoromethyl radical generated by possible pathways from 1 with LTA is discussed.
在 60°C 的
二甘醇中,四
乙酸铅(LTA)可以顺利地诱导二
氟二碘甲烷(1)与富电子烯烃发生加成反应,生成单加成物(RCHICH2
CF2I)和二加成物(RCHICH2)2。
氟烯烃(如
四氟乙烯、
六氟丙烯)与 1 的类似清洁反应只发生在
乙酸中。然而,当 1 与
炔烃在醇中反应时,会得到非
氟化的 δ-
碘-δ±,δ-不饱和
羧酸酯。本文讨论了 1 与 LTA 通过可能的途径生成的
碘氟甲基自由基。