Chiral lewis acid catalysed asymmetric nucleophilic ring opening of cyclohexene oxide

✍ Scribed by Hans Adolfsson; Christina Moberg

• Book ID: 103977232
• Publisher: Elsevier Science
• Year: 1995
• Tongue: English
• Weight: 662 KB
• Volume: 6
• Category: Article
• ISSN: 0957-4166
• DOI: 10.1016/0957-4166(95)00263-o

✦ Synopsis

Titanium and zirconium complexes of bispicolinic amides catalyze the ring opening of cyclohexene oxide with trimethylsilyl azide as nucleophile. The product, l-azido-2trimethylsilyloxycyclohexane, was obtained in up to 71% enantioselectivity when a catalyst prepared from (S,S)-N,N'-bis(2-pyridinecarboxamide)-l,2-diphenylethane and zirconium tetra-tbutoxide was employed under optimum conditions, which included the addition of a small amount of diethylamine in the catalyst preparation step. The nature of the catalyst is still unknown, but it seems probable that oligomeric metal species are involved.