Gold(I)-catalyzed enantioselective [3+2] and [3+3] cycloaddition reactions of propargyl acetals/ketals.

نویسندگان

  • Cristina Navarro
  • Nathan D Shapiro
  • Maurizio Bernasconi
  • Takahiro Horibe
  • F Dean Toste
چکیده

An asymmetric gold(I)-catalyzed [3+2] cycloaddition of propargyl acetals/ketals and aldehydes is reported, which proceeds via stepwise migration-fragmentation of acetals/ketals and cycloaddition of the in situ generated gold-carbenoid intermediate. Various functionalized 2, 5-dihydrofurans were obtained in good yields and high enantioselectivities. Furthermore, an example of the first gold(I) catalyzed [3+3] cycloaddition of secondary propargyl ketals and nitrones is presented.

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عنوان ژورنال:
  • Tetrahedron

دوره 71 35  شماره 

صفحات  -

تاریخ انتشار 2015