Acta Chim. Sinica ›› 2016, Vol. 74 ›› Issue (10): 811-818.DOI: 10.6023/A16070351 Previous Articles     Next Articles

Article

醋酸锰引发的吲哚膦酰化反应

张令, 张沛之, 薛剑飞, 孙网彬, 邹建平   

  1. 江苏省有机合成重点实验室 苏州大学材料与化学化工学部 苏州 215123
  • 收稿日期:2016-07-19 出版日期:2016-10-15 发布日期:2016-09-18
  • 通讯作者: 邹建平,E-mail:jpzou@suda.edu.cn;Tel.:0512-65880336;Fax:0512-65880335 E-mail:jpzou@suda.edu.cn
  • 基金资助:

    项目受国家自然科学基金(No.21472133),江苏高校优势学科建设工程资助项目基金和新型功能高分子材料国家地方联合工程实验室项目基金的资助.

Manganese Acetate-Mediated Phosphorylation of Indoles

Zhang Ling, Zhang Peizhi, Xue Jianfei, Sun Wangbin, Zou Jianping   

  1. Key Laboratory of Organic Synthesis of Jiangsu Province, College of Chemistry and Chemical Engineering, Soochow University, Suzhou, Jiangsu 215123
  • Received:2016-07-19 Online:2016-10-15 Published:2016-09-18
  • Supported by:

    Project supported by the National Natural Science Foundation of China (No. 21472133), the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD) and National and Local Joint Engineering Laboratory of New Functional polymer Materials.

Mn(OAc)3-mediated selective radical phosphorylation of indoles with dialkylphosphites or diphenylphosphine oxide in moderate to good yields is described. The reaction proceeds under mild conditions in air, no need to add extra additives, through a radical process involving phosphorus-centered radical generated from dialkylphosphites or diphenylphosphine oxide mediated by Mn(OAc)3, selectively added to 3-position of 2-substituted indoles or 2-position of 3-substituted indoles to form carbon radical intermediate, followed by oxidation with Mn(OAc)3 and deprotonation to afford products 2- or 3-phosphonyl indoles. This protocol provides an efficient and general method for the preparation of 2- and 3-phosphoryl indoles. The detailed investigation revealed that 1) the yields of N-methyl indoles were higher than NH unprotected analogues; 2) 2-Phenyl or 2-methyl indoles were unsuitable for the reaction with dialkylphosphites, but were suitable for the reaction with diphenyl phosphine oxide; 3) Indoles bearing electron-withdrawing groups such as F, Cl, Br on the phenyl ring were favored to the reaction. A representative procedure for this reaction is as follows: To a solution of substituted indoles 1 or 4 (1 mmol) and dialkylphosphites 2 (2 mmol) in HOAc (3 mL) heated with oil bath (50℃), Mn(OAc)3 (3 mmol) was added in portions within 0.5 h, then, the mixture was allowed to stir further for 0.5 h. After removal of the most solvent under reduced pressure, 50 mL water was added to the residue and the mixture was extracted with EtOAc (20 mL×3). The combined organic layers were dried over anhydrous Na2SO4, filtered, concentrated under reduced pressure, and the residue was purified by flash silica-gel column chromatography (using mixture of petroleum ether/ethyl acetate as eluent from ratio of 20/1 to 1/2) to afford the desired 2- or 3-phosphonyl indoles 3 or 5.

Key words: Mn(OAc)3, radical reaction, indole, phosphorylation