Torquoselective Ring Opening of Fused Cyclobutenamides: Evidence for a Cis,Trans-Cyclooctadienone Intermediate

نویسندگان

  • Xiao-Na Wang
  • Elizabeth H. Krenske
  • Ryne C. Johnston
  • K. N. Houk
  • Richard P. Hsung
چکیده

Electrocyclic ring opening of 4,6-fused cyclobutenamides 1 under thermal conditions leads to cis,trans-cyclooctadienones 2-E,E as transient intermediates, en route to 5,5-bicyclic products 3. Theoretical calculations predict that 4,5-fused cyclobutenamides should likewise undergo thermal ring opening, giving cis,trans-cycloheptadienones, but in this case conversion to 5,4-bicyclic products is thermodynamically disfavored, and these cyclobutenamides instead rearrange to vinyl cyclopentenones.

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عنوان ژورنال:

دوره 136  شماره 

صفحات  -

تاریخ انتشار 2014