Nitroxyl Radical Reactions with 4-Pentenyl- and Cyclopropylketenes: New Routes to 5-Hexenyl- and Cyclopropylmethyl Radicals
作者:Annette D. Allen、Michael F. Fenwick、Huda Henry-Riyad、Thomas T. Tidwell
DOI:10.1021/jo0102922
日期:2001.8.1
in hydrocarbon solvents. The reactions of these ketenes with the nitroxylradicals tetramethylpiperidinyloxyl (TEMPO, TO*) and tetramethylisoindoline-2-oxyl (TMIO, IO*) form carboxy substituted 5-hexenyl and cyclopropylmethyl radicals which are either trapped by a second nitroxylradical or undergo rearrangements followed by trapping. The rate constant of the reaction of 4a with TEMPO was similar to
4-戊烯基酮4a和9以及环丙基烯酮3a,13、14(RCH = C = O)是通过光化学Wolff重排生成的,并且在室温下在烃类溶剂中被IR观察为相对长寿的物种。这些烯酮与硝基氧基四甲基哌啶基氧基(TEMPO,TO *)和四甲基异吲哚啉-2-氧基(TMIO,IO *)的反应形成羧基取代的5-己烯基和环丙基甲基,它们被第二个硝基氧基所俘获或进行重排通过诱捕。4a与TEMPO的反应速率常数与n-BuCH = C = O(1b)相似,而3a的反应速率高4.3倍,表明初始自由基的环丙基稳定性。
Intramolecular [2+2] cycloadditions of ketenes and keteniminium salts to olefins
作者:Istvan Marko、Bruno Ronsmans、Anne Marie Hesbain-Frisque、Stephane Dumas、Leon Ghosez、Beat Ernst、Hans Greuter
DOI:10.1021/ja00293a073
日期:1985.4
On prepare une serie de cetones bicycliques par cycloaddition de cetenes et de sels de ceteneiminium derives d'acides aliphatiques insatures
制备 une serie de cetones bicycliques par cycloaddition de cetenes et de sels de ceteneiminium 衍生 d'acides aliphatiques insatures