Neutral iridium catalysts with chiral phosphine-carboxy ligands for asymmetric hydrogenation of unsaturated carboxylic acids.

نویسندگان

  • Shuang Yang
  • Wen Che
  • Hui-Ling Wu
  • Shou-Fei Zhu
  • Qi-Lin Zhou
چکیده

We developed neutral iridium catalysts with chiral spiro phosphine-carboxy ligands (SpiroCAP) for asymmetric hydrogenation of unsaturated carboxylic acids. Different from the cationic Crabtree-type catalysts, the iridium catalysts with chiral spiro phosphine-carboxy ligands are neutral and do not require the use of a tetrakis[3,5-bis(trifluoromethyl)phenyl]borate (BArF-) counterion, which is necessary for stabilizing cationic Crabtree-type catalysts. Another advantage of the neutral iridium catalysts is that they have high stability and have a long lifetime in air. The new iridium catalysts with chiral spiro phosphine-carboxy ligands exhibit unprecedented high enantioselectivity (up to 99.4% ee) in the asymmetric hydrogenations of various unsaturated carboxylic acids, particularly for 3-alkyl-3-methylenepropionic acids, which are challenging substrates for other chiral catalysts.

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منابع مشابه

Neutral iridium catalysts with chiral phosphine-carboxy ligands for asymmetric hydrogenation of unsaturated carboxylic acids† †Electronic supplementary information (ESI) available: For CIF data of (S)-2d, experimental procedures, and characterization data. CCDC 1498903. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c6sc03764j Click here for additional data file. Click here for additional data file.

Neutral Iridium Catalysts with Chiral Phosphine-Carboxy Ligands for Asymmetric Hydrogenation of Unsaturated Carboxylic Acids Shuang Yang, Wen Che, Hui-Ling Wu, Shou-Fei Zhu* and Qi-Lin Zhou* a State Key Laboratory and Institute of Elemento-Organic Chemistry, Nankai University, Tianjin 300071, China b Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin 300071, ...

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عنوان ژورنال:
  • Chemical science

دوره 8 3  شماره 

صفحات  -

تاریخ انتشار 2017