从N- ( 2-乙烯基苯基)酰胺和通过在 50 °C 下使用 K 2 S 2 O 8活性炭在乙腈水溶液中的混合物制备硫醇。报道了该反应的合理机制。这表明该反应遵循自由基途径,过硫酸盐一直是产物中形成砜基团的氧源。值得一提的是,该协议采用了易于访问的 K 2 S 2 O 8- 活性炭混合物和硫醇,首次分别作为氧化剂和磺酰化前体。
Electrochemical oxidative radical cascade cyclization of olefinic amides and thiophenols towards the synthesis of sulfurated benzoxazines, oxazolines and iminoisobenzofurans
containing N and O are important structures in pharmaceuticals, agrochemicals and functional molecules. The synthesis of these compounds usually requires complex substrates and harsh reaction conditions. Herein, we introduce a mild and efficient electrochemical oxidative strategy to construct benzoxazines, oxazolines and iminoisobenzofurans without the requirement of a transition-metal catalyst and an
含 N 和 O 的杂环是药物、农用化学品和功能分子中的重要结构。这些化合物的合成通常需要复杂的底物和苛刻的反应条件。在此,我们引入了一种温和有效的电化学氧化策略来构建苯并恶嗪、恶唑啉和亚氨基异苯并呋喃,而无需过渡金属催化剂和外部氧化剂。在一个简单的未分开的细胞中,各种烯酰胺和苯硫酚/二硒化物反应生成 69 个硫醇化和硒化杂环的例子,产率高达 83%。此外,这种自由基级联反应为一步构建 C-S/C-Se 和 C-O 键提供了一种简便的方法。
Copper-catalyzed trifluoromethylation of alkenes: synthesis of trifluoromethylated benzoxazines
base and ligand free copper catalyzed method for the construction of trifluoromethylated benzoxazines has been developed by using Umemoto's reagent. It involves the oxidative difunctionalization of alkenes through tandem C–O and C–CF3 bond formations. Furthermore, synthesized benzoxazines were selectively converted into trifluoromethylated allylic and (E)-vinylic benzamides by the treatment of KOtBu
通过使用梅本试剂开发了一种简单的无碱和无配体铜催化的三氟甲基化苯并恶嗪的构建方法。它涉及通过串联的C–O和C–CF 3键形成烯烃的氧化双官能团。此外,通过分别处理KO t Bu和CH 3 Li,将合成的苯并恶嗪选择性地转化为三氟甲基化的烯丙基和(E)-乙烯基苯甲酰胺。
Efficient synthesis of SCF<sub>3</sub>-substituted tryptanthrins by a radical tandem cyclization
作者:Jincheng Guo、Yanan Hao、Gang Li、Ziwen Wang、Yuxiu Liu、Yongqiang Li、Qingmin Wang
DOI:10.1039/d0ob00233j
日期:——
we report a new, efficient and atom-economical strategy for the synthesis of SCF3-substituted tryptanthrin derivatives. These previously unreported derivatives were obtained by means of a radical tandem cyclization. The reaction was triggered by addition of a SCF3 radical to a carbon-carbon double bond and involved the formation of a C(sp3)-SCF3 bond, a C(sp2)-C bond, and a C(sp2)-N bond. This method
Silver or cerium-promoted free radical cascade difunctionalization of <i>o</i>-vinylanilides with sodium aryl- or alkylsulfinates
作者:Jilai Wu、Yuanyuan Zong、Chunxia Zhao、Qinqin Yan、Lixian Sun、Yiming Li、Jincan Zhao、Yaxin Ge、Zejiang Li
DOI:10.1039/c8ob02964d
日期:——
oxysulfonylation of o-vinylanilides with sodium aryl- or alkylsulfinates by a free radical mechanism has been developed, which provides a mild, facile and convenient method for the synthesis of various benzoxazines. Control experiments, including gram-level reactions and mechanistic studies, are involved in the reaction system.
A copper-catalyzedC(sp3)–H bondfunctionalization of simple alkanes with olefinic amides was developed for the efficient synthesis of important benzoxazine derivatives. It involves new C-C and C-O bondformation in one step via radical cascade process.