Department of Applied Chemistry, National Chiao Tung University , Hsinchu 30010, Taiwan.
Department of Chemistry, National Tsing Hua University , Hsinchu 30013, Taiwan.
Org Lett. 2017 Aug 4;19(15):4134-4137. doi: 10.1021/acs.orglett.7b01956. Epub 2017 Jul 18.
A palladium-catalyzed C-H bond activation reaction, via a redox-neutral pathway, for the preparation of dihydrophenanthridine, phenanthridine, and carbazole derivatives from biaryl 2-iminoquinones is developed. The preinstalled iminoquinone was designed to act as a directing group for ortho C-H activation and an internal oxidant or a co-oxidant. This catalysis proceeded through the following sequence: C-H bond activation, coordination and insertion of activated olefins, β-hydride elimination, H-shift, insertion, and protonation or β-hydride elimination. In addition, carbazoles can be prepared efficiently by using this method without the addition of external oxidants.
发展了一种钯催化的 C-H 键活化反应，通过氧化还原中性途径，从联芳基 2-亚氨基喹酮制备二氢菲啶、菲啶和咔唑衍生物。预安装的亚氨基喹酮被设计为邻位 C-H 活化的导向基团和内部氧化剂或共氧化剂。该催化反应经过以下顺序进行：C-H 键活化、活化烯烃的配位和插入、β-氢消除、H-迁移、插入和质子化或β-氢消除。此外，通过这种方法可以有效地制备咔唑，而无需添加外部氧化剂。
