3,3-Difluoro-1-iodocyclopropenes: A Simple Synthesis and Their Reactions
摘要:
The [1 + 2] cycloaddition reaction of 1-iodoalkynes with difluorocarbene, generated from the decomposition of FSO2CF2COOSiMe3 in diglyme in the presence of 10 mol % NaF at 120 degreesC, gives 3, 3-difluoro-1-iodocyclopropenes in good yields. These new iodides can be trifluoromethylated and functionalized via the Heck reaction. The unusual hydrolytic reactions of the iodides under acidic conditions was also investigated.
Difluorocarbene chemistry: synthesis of gem-difluorocyclopropenylalkynes and 3,3,3′,3′-tetrafluorobicyclopropyl-1,1′-dienes
作者:Zhan-Ling Cheng、Qing-Yun Chen
DOI:10.1016/j.jfluchem.2004.10.012
日期:2005.1
by the Sonogashira reaction of 3,3-difluoro-1-iodocyclopropenes with terminal alkynes. Onto these new alkynes addition of difluorocarbene, generated from the decomposition of FSO2CF2COOTMS in diglyme in the presence of 10 mol% anhydrous NaF at 120 °C, gives 3,3,3′,3′-tetrafluorobicyclopropyl-1,1′-dienes. Acid hydrolysis of gem-difluorocyclopropenylalkynes in refluxing CH3OH affords the corresponding
carried out in laboratory illumination to give the corresponding substituted product. The presence of p-dinitrobenzene (p-DNB) or hydroquinone (HQ) as well as darkness significantly suppressed the reaction. ESR trapping experiments also evidenced the existence of fluorinated radical. All these results demonstrate the reaction involved a vinylic saturated alkyl and aromatic halides (SRN1) mechanism.