REACTION OF PERFLUORO-2-METHYL-2-PENTENE WITH CYCLOALKANONE OXIMES - NEW EXAMPLES OF THE BECKMAN-CHAPMAN REARRANGEMENT

The base-catalyzed reaction of cycloalkanone oximes (1a,b) with perfluoro-2-methyl-2-pentene (PFMP) initially affords the addition products, i.e., fluoroalkyl ethers (2a,b). In the presence of KOH, the latter undergoes dehydrofluorination to give perfluoroalkenyl ether; (3a,b). Thermolysis of ethers 3a,b results in compounds of two types - pyrrolines (4a,b) and N-perfluoroalkenyl lactams (5a,b). The latter are also prepared from PFMP and the corresponding lactams. The structure of N-[perfluoro-(2-methyl-2-penten-3-yl)]-2-pyrrolidone (5c) was established by X-ray diffraction study.