Transition-Metal-Free Dehydrogenative Cyclization via α-Csp3–H Activation of Ethers and Thioethers
作者:Ranjan Jana、Kartic Manna、Hasina Mamataj Begam
DOI:10.1055/a-2017-6065
日期:——
S-alkylated salicylic or thiosalicylic acid derivatives to access 4H-benzo[d][1,3]dioxin-4-ones or 4H-benzo[d][1,3]oxathiin-4-ones, respectively. The oxidative cyclization of salicylic acid derivatives proceeds through a radical pathway at 110 °C. In contrast, the cyclization of the thiosalicylic acids proceeds smoothly at room temperature via an ionic pathway. Notably, the overall reactions are fast, completed
我们在此报道了四乙基溴化铵催化 O- 或 S- 烷基化水杨酸或硫代水杨酸衍生物的分子内氧化环化以获得 4 H -苯并[ d ] [1,3] 二恶英-4-酮或 4 H -苯并[ d ] [ 1,3]oxathiin-4-ones,分别。水杨酸衍生物的氧化环化在 110 °C 通过自由基途径进行。相反,硫代水杨酸的环化在室温下通过离子途径顺利进行。值得注意的是,整体反应速度快,反应时间短,产品收率高,季碳中心形成顺利。