Enantioselective protonation of α-hetero carboxylic acid-derived ketene disilyl acetals under chiral ionic Brønsted acid catalysis.

نویسندگان

  • Daisuke Uraguchi
  • Tomohito Kizu
  • Yuki Ohira
  • Takashi Ooi
چکیده

Highly enantioselective protonation of α-halo and alkoxy carboxylic acid-derived ketene disilyl acetals is achieved by using P-spiro chiral diaminodioxaphosphonium barfate as a Brønsted acid catalyst, where the enantiofacial discrimination by the catalyst mainly stems from the recognition of the electronic difference between two substituents on the ketene disilyl acetal.

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عنوان ژورنال:
  • Chemical communications

دوره 50 88  شماره 

صفحات  -

تاریخ انتشار 2014