Collect. Czech. Chem. Commun. 1980, 45, 104-114

Aluminium chloride induced isomerisation of 1,1,2-trichlorotrifluoroethane and 1,2-difluorotetrachloroethane

Oldřich Paleta, František Liška, Antonín Pošta and Václav Dědek

Department of Organic Chemistry, Prague Institute of Chemical Technology, 166 28 Prague 6


Under comparable conditions, the isomerisation of 1,1,2-trichlorotrifluoroethane (I) to 1,1,1-trichlorotrifluoroethane (II) is more difficult than the isomerisation of 1,2-difluorotetrachloroethane (III) to 1,1-difluorotetrachloroethane (IV). Advantageously, III was isomerised to IV in the presence of I or II. The degree of isomerisation of the starting compounds I and III was 95-99%, the preparative yield of IV being 65-74%. The C-F bond energies in I-IVwere derived from correlation diagram and the physico-chemical aspects of the isomerisation are discussed.