Visible-Light-Enhanced Ring Opening of Cycloalkanols Enabled by Brønsted Base-Tethered Acyloxy Radical Induced Hydrogen Atom Transfer-Electron Transfer
作者:Rong Zhao、Yuan Yao、Dan Zhu、Denghu Chang、Yang Liu、Lei Shi
DOI:10.1021/acs.orglett.8b00161
日期:2018.2.16
A metal-free ring opening/halogenation of cycloalkanols, which combines both PPO/TBAX oxidant system and blue LEDs irradiation, is presented. This method produces diverse γ, δ, and even more remotely halogenated ketones in moderate to excellent yields under mild conditions. Interestingly, experimental and computational studies demonstrate the novel ring size-dependent concerted/stepwise (four-/five-
提出了结合了PPO / TBAX氧化剂系统和蓝色LED辐射的无金属环烷醇开环/卤化反应。该方法在温和条件下以中等至极佳的收率生产出多种γ,δ甚至更遥远的卤代酮。有趣的是,实验和计算研究表明,布朗斯台德碱式束缚的酰氧基基团诱导了新颖的环尺寸依赖性的一致/逐步(四元/五元至五元至八元环)氢原子转移-电子转移,这表明氢氧自由基带来了明显的优势。二酰基过氧化物的环状结构。