Sodium dithionite initiated addition of CF2Br2, CF3I and (CF3)2CFI to allylaromatics
作者:Jolanta Ignatowska、Wojciech Dmowski
DOI:10.1016/j.jfluchem.2007.04.028
日期:2007.9
difluoromethylene group in the ring. The reactions of CF3I and (CF3)2CFI with allylbenzenes gave the respective adducts, (4,4,4-trifluoro-2-iodobutyl)benzenes and 1-(4,5,5,5-tetrafluoro-4-(trifluoromethyl)-2-iodopentyl)benzenes as the main products. Dehydrohalogenation of these adducts resulted, respectively, in (4,4,4-trifluoro-but-1-enyl)benzenes and 4-aryl-1,1-bis(trifluoromethyl)butadienes in high yields
研究了在MeCN / H 2 O系统中,连二亚硫酸钠引发的CF 2 Br 2,CF 3 I和(CF 3)2 CFI加至烯丙基苯的末端双键和(CF 3)2 CFI加至烯丙基吡啶的末端双键。CF 2 Br 2的反应与烯丙基苯的加合物,1-(2,4-二溴-4,4-二氟丁基)苯,脱溴产物,1-(4-溴-4,4-二氟丁基)苯和二聚体化合物的总收率相近40 –66%。用DBU处理加合物导致两次脱卤化氢,得到4-芳基-1,1-二氟丁二烯,与二亲氮的氮进行Diels-Alder缩合反应,得到环中带有二氟亚甲基的N-杂环。CF 3 I和(CF 3)2的反应与烯丙基苯的CFI得到相应的加合物,(4,4,4-三氟-2-碘丁基)苯和1-(4,5,5,5-四氟-4-(三氟甲基)-2-碘戊基)苯产品。这些加合物的脱卤化氢分别以高收率产生了(4,4,4-三氟丁-1-烯基)苯和4-芳基-1,1-双(三氟甲基)丁二烯。(CF