Synthesis and structure elucidation of bromination products from dibromohomobenzonorbornadienes: high temperature bromination—Part 17

✍ Scribed by Cavit Kazaz; Arif Daştan; Metin Balcı

• Publisher: John Wiley and Sons
• Year: 2004
• Tongue: English
• Weight: 177 KB
• Volume: 43
• Category: Article
• ISSN: 0749-1581
• DOI: 10.1002/mrc.1490

✦ Synopsis

Abstract

The electrophilic addition of bromine to dibromohomobenzonorbornadiene derivatives at −45 ± 5°C led to the formation of the rearranged and non‐rearranged tetrabromides in a ratio of 6:4. However, high‐temperature bromination of the same system in CCl~4~ at 77°C produced only non‐rearranged products. The formation mechanism of the isomers and the role of the substituent on the rearrangement is discussed. The structure elucidation of the isomeric tetrabromides was achieved from NMR spectral data. The agreement between the calculated dihedral angles and the measured coupling constants is especially excellent. The γ‐gauche effect is discussed. Copyright © 2004 John Wiley & Sons, Ltd.