Asymmetric synthesis of chiral trifluoromethylated heliotridane via highly catalytic asymmetric Friedel–Crafts alkylation with β-trifluoromethylated acrylates and pyrroles
作者:Yiyong Huang、Satoru Suzuki、Guokai Liu、Etsuko Tokunaga、Motoo Shiro、Norio Shibata
DOI:10.1039/c1nj20550a
日期:——
Chiral Ph-dbfox (Ph-dbfox = (R,R)-4,6-dibenzofurandiyl-2,2â²-bis(4-phenyloxazoline))/Zn(NTf2)2 catalyzed enantioselective FriedelâCrafts reactions of β-CF3 acrylates with pyrroles and indoles have been investigated, which afforded the corresponding chiral trifluoromethyl pyrrole and indole derivatives in high yields (90â99%) with a range of 66â99% ee values. With the aid of the chiral adduct of the asymmetric FriedelâCrafts reaction, the chiral trifluoromethylated heliotridane has been successfully constructed in good total yield.
研究了由手性Ph-dbfox (Ph-dbfox = (R,R)-4,6-二苯并呋喃二基-2,2'-双(4-苯氧噁唑))/Zn(NTf2)2 催化的enantioselective Friedel–Crafts反应,其中β-CF3丙烯酸酯与吡咯和吲哚反应,得到了相应的手性三氟甲基吡咯和吲哚衍生物,产率高达90-99%,光学纯度(ee值)范围为66-99%。借助于不对称Friedel–Crafts反应的手性加成物,成功合成了手性三氟甲基化的海特立烷,且总产率良好。