• DOI:10.5012/BKCS.2003.24.1.015
• Corpus ID: 97122511

Lewis Acid-Promoted Radical Carbon-Carbon Bond Forming Reactions with N-Ethylpiperidine Hypophosphite

@article{Cho2003LewisAR,
  title={Lewis Acid-Promoted Radical Carbon-Carbon Bond Forming Reactions with N-Ethylpiperidine Hypophosphite},
  author={Dae Hyan Cho and Doo Ok Jang},
  journal={Bulletin of The Korean Chemical Society},
  year={2003},
  volume={24},
  pages={15-16}
}

• D. Cho, D. Jang
• Published 2003
• Chemistry
• Bulletin of The Korean Chemical Society

Construction of carbon-carbon bonds is one of the most important tasks in organic synthesis, and the well-developed radical reactions have become important synthetic tools for forming carbon-carbon bonds of biologically important molecules. 1 In the process, organotin hydrides have played a major role. Although organotin hydrides give high yields, they have several drawbacks. Their toxicity prevents them from being used on a practical scale, and it is difficult to eliminate toxic by-products from the desired products. Therefore, organotin hydrides are not acceptable in an industrial process of manufacturing drugs and medicines. Consequently, various alternatives to organotin hydrides have been reported. 2 Among them, hypophosphorous acid and its salts have shown to be suitable alternatives to organotin hydrides in radical reactions. 3 Hypophosphorous acid and its salts have advantages over organotin hydrides in cost-effectiveness, non-toxicity and easy work-up process. Electron-deficient alkenes are generally employed in radical carbon-carbon bond forming reactions because of the nucleophilic character of alkyl radicals which are the most frequently used radical donors in organic synthesis. 1d,4 However, it is not easy to accomplish the radical carbon-carbon bond forming reactions with β-substituted alkenes even though β-substituted alkenes have an electron-withdrawing group. Therefore, a general method for the radical carboncarbon bond forming reactions with β-substituted alkenes is highly appreciated. Our recent studies on the radical addition reactions with N-ethylpiperidine hypophosphite (EPHP) showed that βsubstituted alkenes are hardly radical acceptors. 3j Recently, Lewis acids are frequently employed in radical reactions, especially for stereoselective radical reactions. 6 We anticipated that use of Lewis acids in radical addition reactions