Two-step conversion of carboxylic esters into distally fluorinated ketones via ring cleavage of cyclopropanol intermediates: application of sulfinate salts as fluoroalkylating reagents
作者:Yulia A. Konik、Marina Kudrjashova、Nele Konrad、Sandra Kaabel、Ivar Järving、Margus Lopp、Dzmitry G. Kananovich
DOI:10.1039/c7ob00680b
日期:——
used in the synthesis of distally fluorinated ketones. Cyclopropane ring cleavage reactions in methanol with aqueous tert-butyl hydroperoxide in the presence of a copper(II) acetate catalyst and sodium triflinate (Langlois reagent) afford β-trifluoromethyl ketones in 16–74% isolated yields. Sodium triflinate serves as a precursor of reactive trifluoromethyl copper species, enabling ring-opening trifluoromethylation
易于从羧酸酯中获得的叔环丙醇已用于合成远端氟化的酮。铜存在下甲醇与叔丁基过氧化氢在甲醇中的环丙烷环裂解反应(II)乙酸盐催化剂和三氟甲磺酸钠(Langlois试剂)可提供16-74%的分离产率的β-三氟甲基酮。三氟甲磺酸钠用作反应性三氟甲基铜物质的前体,使开环三氟甲基化成为可能,这已通过机理研究证明。在此我们还证明了其他亚磺酸盐,例如1,1-二氟乙烷亚磺酸钠,2-(4-溴苯基)-1,1-二氟乙烷亚磺酸钠和1-(三氟甲基)环丙烷亚磺酸钠也可用作氟代烷基化试剂,相应的氟化酮。