Bromination of an N-carbethoxy-7-aza-2,3-benzonorbornadiene and synthesis of N-carbethoxy-7-aza-2,3-dibromo-5,6-benzonorbornadiene: High temperature bromination. Part 14

Tutar A., Balci M.

TETRAHEDRON, vol.58, no.44, pp.8979-8984, 2002 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 58 Issue: 44
  • Publication Date: 2002
  • Doi Number: 10.1016/s0040-4020(02)01150-x
  • Journal Name: TETRAHEDRON
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.8979-8984
  • Middle East Technical University Affiliated: No

Abstract

The electrophilic addition of bromine to an N-carbethoxy-7-aza-2,3-benzonorbomadiene at 0degreesC led in high yield to the formation of rearranged dibromides. However, high-temperature bromination of N-carbethoxy-7-aza-2,3-benzonorbomadiene in carbon tetrachloride at 77degreesC while irradiating, gave exclusively non-rearranged products. From the elimination of these non-rearranged products, N-carbethoxy4-bromo-7-aza-2,3-benzonorbomadiene was obtained as the sole product. Similarly, bromination of monobromide N-carbethoxy-4-bromo7-aza-2,3-benzonorbomadiene at 77degreesC yielded non-rearranged tribromides. The dehydrobromination of these tribromides provided the N-carbethoxy-5,6-dibromo-7-aza-2,3-benzonorbomadiene in high yield, which is a synthon for trimerization reaction. (C) 2002 Elsevier Science Ltd. All rights reserved.