Fluorination with xenon difluoride. Part 15. Stereochemistry of fluorine addition to acenaphthylene and dihydronaphthalenes

Abstract

Acid-catalysed liquid-phase addition of fluorine by xenon difluoride to acenaphthylene and 1,2-dihydronaphthalene gives vicinal difluorides in high yield. The addition proceeds predominantly via trans-attack. The reaction with 1,4-dihydronaphthalene affords a complex mixture of naphthalene, 1-fluoronaphthalene, 2-fluoronaphthalene, and 2-fluoro-1,2,3,4-tetrahydronaphthalene.