Efficient Access to Extended Yagupolskii-Umemoto-Type Reagents: Triflic Acid Catalyzed Intramolecular Cyclization of ortho-Ethynylaryltrifluoromethylsulfanes
作者:Andrej Matsnev、Shun Noritake、Yoshinori Nomura、Etsuko Tokunaga、Shuichi Nakamura、Norio Shibata
DOI:10.1002/anie.200905225
日期:2010.1.12
King of the ring: S‐(trifluoromethyl)benzo[b]thiophenium salts 1, as analogues of Yagupolskii–Umemoto type reagents, were synthesized by novel triflic acid catalyzed intramolecular cyclization of ortho‐ethynylaryltrifluoromethylsulfanes 2. 1 j is especially useful for the electrophilic trifluoromethylation of β‐ketoesters and dicyanoalkylidenes.
环中之王:S-(三氟甲基)苯并[b]噻吩盐1作为Yagupolskii–Umemoto型试剂的类似物,是通过新颖的三氟甲磺酸催化的邻乙炔基芳基三氟甲基硫烷2的分子内环化反应合成的。1 j对于亲电性特别有用β-酮酸酯和二氰基亚烷基的三氟甲基化。