Phosphazene-catalyzed intramolecular cyclization of nitrogen-tethered alkynyl esters.

نویسندگان

  • Azusa Kondoh
  • Kenichi Ando
  • Masahiro Terada
چکیده

Intramolecular cyclization of nitrogen-tethered alkynyl esters catalyzed by phosphazene organosuperbases P2-tBu and P4-tBu was investigated. Both acyclic and cyclic substrates underwent 5-exo-dig and 5-endo-dig cyclization. This reaction is a rare example of the intramolecular addition of enolates of simple esters to alkynes.

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عنوان ژورنال:
  • Chemical communications

دوره 49 87  شماره 

صفحات  -

تاریخ انتشار 2013