Interrupting the Nazarov Cyclization with Bromine.

J Org Chem

Department of Chemistry, University of Alberta , E3-43 Gunning-Lemieux Chemistry Centre, Edmonton, AB, Canada.

Published: December 2016

AI Article Synopsis

  • The study presents a method to create dibrominated cyclopentenones using an interrupted Nazarov cyclization process.
  • The reaction involves adding bromine to specific positions (α and α') on the cyclopentenyl structure through a series of nucleophilic and electrophilic substitutions.
  • The method notably yields a symmetrical product with good diastereoselectivity, meaning the reaction tends to produce one stereoisomer over others.

Article Abstract

The generation of dibrominated cyclopentenones via an interrupted Nazarov cyclization is reported. The installation of two bromine atoms occurs at the α and α' positions of the cyclopentenyl scaffold via successive nucleophilic and electrophilic bromination of the 2-oxidocyclopentenyl cation and its resulting enolate. Notably, the reaction proceeds with good diastereoselectivity, favoring the symmetrical product.

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http://dx.doi.org/10.1021/acs.joc.6b02350DOI Listing

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