Selective bromination of 1-bromonaphthalene: efficient synthesis of bromonaphthalene derivatives


Cakmak O., Demirtas I., Balaydin H.

TETRAHEDRON, cilt.58, ss.5603-5609, 2002 (SCI İndekslerine Giren Dergi) identifier identifier

  • Cilt numarası: 58 Konu: 28
  • Basım Tarihi: 2002
  • Doi Numarası: 10.1016/s0040-4020(02)00549-5
  • Dergi Adı: TETRAHEDRON
  • Sayfa Sayıları: ss.5603-5609

Özet

Selective and specific preparation methods are described for 1,4-dibromonaphthalene, 1,5-dibromonaphthalene and 1,3,5-tribromonaphthalene. The reaction of 1-bromonaphthalene and naphthalene with stoichometric quantities of bromine by using a minimum amount of solvent (methylene chloride) at -30 and -50degreesC smoothly affords 1,4-dibromonaphthalene in 90% yield. Photobromination of 1-bromonaphthalene in CCl4 at -30degreesC gives 1,2,3,4,5-pentabromo-1,2,3,4-tetrahydronaphthalenes, whereas 1,5-dibromonaphthalene is obtained at reflux (77degreesC) in 80% yield under the same conditions. Dehydrobromination of the pentabromide by t-BuOK affords 1,3,5-tribromonaphthalene as a sole product (91%). 1,5-Dibromo- and 1,3,5-tribromonaphthalenes were efficiently converted to the corresponding methoxy naphthalene derivatives. (C) 2002 Elsevier Science Ltd. All rights reserved.