Saito Hayate, Nogi Keisuke, Yorimitsu Hideki
Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto, 606-8502, Japan.
Angew Chem Int Ed Engl. 2018 Aug 20;57(34):11030-11034. doi: 10.1002/anie.201806237. Epub 2018 Jul 23.
The catalytic ring-opening silylation of benzofurans has been achieved by employing a copper catalyst and 1,2-di-tert-butoxy-1,1,2,2-tetramethyldisilane, which could be easily prepared and handled without special care. The reaction afforded (E)-o-(β-silylvinyl)phenols with complete stereoselectivity. The scope of benzofurans was well explored, and functional groups such as chloro, fluoro, and acetal were compatible with the reaction conditions. DFT calculations were used to determine the energy profile of the silylation and the origin of the stereoselectivity. The silylated product was proven to be useful as a synthetic intermediate and subsequently underwent transformations such as Pd-catalyzed cross-coupling with iodoarenes.
通过使用铜催化剂和1,2-二叔丁氧基-1,1,2,2-四甲基二硅烷，实现了苯并呋喃的催化开环硅基化反应，该二硅烷易于制备且无需特别小心即可处理。该反应以完全的立体选择性得到(E)-邻-(β-硅基乙烯基)苯酚。对苯并呋喃的范围进行了充分探索，氯、氟和缩醛等官能团与反应条件兼容。使用密度泛函理论(DFT)计算来确定硅基化反应的能量分布以及立体选择性的来源。经证明，硅基化产物作为合成中间体很有用，随后可进行诸如与碘代芳烃的钯催化交叉偶联等转化反应。
