High temperature bromination. Part 12: Bromination of 7-oxabenzonorbornadiene: Synthesis of 2,3-dibromo-7-oxabenzonorbornadiene

Altundas A., DAŞTAN A., McKee M., Balci M.

TETRAHEDRON, cilt.56, sa.33, ss.6115-6120, 2000 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 56 Sayı: 33
  • Basım Tarihi: 2000
  • Doi Numarası: 10.1016/s0040-4020(00)00561-5
  • Dergi Adı: TETRAHEDRON
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.6115-6120
  • Gazi Üniversitesi Adresli: Hayır

Özet

The electrophilic addition of bromine to 7-oxabenzonorbornadiene (8) at 0 degrees C led in high yield to the formation of dibromoaldehyde 10. However, high-temperature bromination of 8 in carbontetrachloride at 77 degrees C gave non-rearranged products 17 and 18. From the elimination of non-rearranged products, 2-bromo-7-oxabenzonorbornadiene (12) was obtained. Similarly, bromination of monobromide 12 at 77 degrees C yielded the non-rearranged tribromides 19 and 20 while bromination of 12 at 0 degrees C gave the rearranged product 11. The dehydrobromination of tribromides (19, 20) provided the 2,3-dibromo-7-oxabenzonorbornadiene (21), which is a synthon for the trimerization, in high yield (C) 2000 Elsevier Science Ltd. All rights reserved.