Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster , Corrensstraße 40, 48149 Münster, Germany.
Org Lett. 2018 Mar 2;20(5):1316-1319. doi: 10.1021/acs.orglett.8b00052. Epub 2018 Feb 15.
An operationally simple protocol is disclosed to facilitate entry to benzo-3,4-coumarins directly from biaryl carboxylic acids without the need for substrate prefunctionalization. Complementary to classic lactonization strategies, this disconnection relies on the oxidation competence of photoactivated (-)-riboflavin (vitamin B) to generate the heterocyclic core via photoinduced single electron transfer. Collectively, the inexpensive nature of the catalyst, ease of execution, and absence of external metal additives are a convincing endorsement for the incorporation of simple vitamins in contemporary catalysis.
现公开了一种操作简单的方案，可直接从联芳基羧酸中方便地进入苯并-3,4-香豆素，而无需对底物进行预官能化。与经典的内酯化策略互补，这种断开依赖于光激活（-）-核黄素（维生素 B）的氧化能力，通过光诱导单电子转移生成杂环核心。总的来说，催化剂成本低廉、易于实施且不存在外部金属添加剂，这充分证明了在当代催化中简单维生素的应用具有吸引力。
