Highly selective allylborations of aldehydes using α,α-disubstituted allylic pinacol boronic esters.

نویسندگان

  • Matthew J Hesse
  • Stéphanie Essafi
  • Charlotte G Watson
  • Jeremy N Harvey
  • David Hirst
  • Christine L Willis
  • Varinder K Aggarwal
چکیده

α,α-Disubstituted allylic pinacol boronic esters undergo highly selective allylborations of aldehydes to give tetrasubstituted homoallylic alcohols with exceptional levels of anti-Z-selectivity (>20:1). The scope of the reaction includes both acyclic and cyclic allylic boronic esters which lead to acyclic and exocyclic tetrasubstituted homoallylic alcohols. The use of β-borylated allylic boronic esters gave fully substituted alkenes bearing a boronic ester which underwent further cross-coupling enabling a highly modular and stereoselective approach to the synthesis of diaryl tetrasubstituted alkenes. Computational analysis revealed the origin of the remarkable selectivity observed.

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عنوان ژورنال:
  • Angewandte Chemie

دوره 53 24  شماره 

صفحات  -

تاریخ انتشار 2014