Electroreductive Intramolecular Coupling of Aromatic β- and γ-Imino Esters: A New Synthetic Method for <i>N</i>-Alkoxycarbonyl-2-aryl-3-ones and <i>cis</i>-2-Aryl-3-ols of Pyrrolidines and Piperidines
作者:Naoki Kise、Kengo Ohya、Kie Arimoto、Yutaka Yamashita、Yuuki Hirano、Tadahiro Ono、Nasuo Ueda
DOI:10.1021/jo0488917
日期:2004.10.1
the resulting five- and six-membered cyclized amines gave mixed ketals of N-alkoxycarbonyl-2-arylpyrrolidin-3-ones and 2-arylpiperidin-3-ones, respectively. The best result of the electroreductive intramolecular coupling was achieved using Bu4NClO4 as a supporting electrolyte and a Pb cathode in THF. Acid hydrolysis of the mixed ketals afforded N-alkoxycarbonyl-2-arylpyrrolidin-3-ones and 2-arylpiperidin-3-ones
芳族β-和γ亚氨基酯的电解还原从β丙氨酸和γ-氨基丁酸制备甲基氯硅烷中和随后的存在Ñ所得的五元和六元环化胺的-alkoxycarbonylation得到的混合缩酮ñ -烷氧基羰基-2- arylpyrrolidin分别为-3-ones和2-芳基哌啶-3-ones。使用Bu 4 NClO 4作为支持电解质和THF中的Pb阴极可获得最佳的电还原分子内偶联结果。混合缩酮的酸水解以良好的产率得到了N-烷氧基羰基-2-芳基吡咯烷-3-酮和2-芳基哌啶-3-酮。在甲醇中用NaBH 4还原这些酮可得到相应的Ñ -alkoxycarbonyl-顺-2- arylpyrrolidin -3-醇类和顺-2- arylpiperidin -3-醇类diastereospecifically。