Liu Zhuqing, Huang Fei, Lou Jiang, Wang Quannan, Yu Zhengkun
Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian, Liaoning 116023, People's Republic of China.
Org Biomol Chem. 2017 Jul 5;15(26):5535-5540. doi: 10.1039/c7ob01234a.
Copper-promoted direct C-H alkoxylation of S,S-functionalized internal olefins, that is, α-oxo ketene dithioacetals, was efficiently achieved with alcohols as the alkoxylating agents, (diacetoxyiodo)benzene (PhI(OAc)) as the oxidant, and benzoquinone (BQ) as the co-oxidant. The alkoxylated olefins were thus constructed and applied for the synthesis of alkoxylated N-heterocycles. The polarization of the olefinic carbon-carbon double bond by the electron-donating dialkylthio and electron-withdrawing α-oxo functionalities plays a crucial role in making such C-H alkoxylation reactions to occur under mild conditions. Mechanistic studies implicate a single-electron-transfer (SET) reaction pathway involved in the overall catalytic cycle.
以醇为烷氧基化试剂、（二乙酰氧基碘）苯（PhI(OAc)）为氧化剂、苯醌（BQ）为共氧化剂，铜促进的S，S-官能化内烯烃（即α-氧代烯酮二硫代乙酸酯）的直接C-H烷氧基化反应得以高效实现。由此构建了烷氧基化烯烃，并将其应用于烷氧基化N-杂环的合成。供电子的二烷基硫基和吸电子的α-氧代官能团对烯烃碳-碳双键的极化作用，在使此类C-H烷氧基化反应在温和条件下发生过程中起着关键作用。机理研究表明，整个催化循环涉及单电子转移（SET）反应途径。
