REACTIONS INVOLVING HEXAFLUOROPROPYLENE OXIDE - NOVEL RING-OPENING REACTIONS AND RESOLUTION OF A RACEMIC-MIXTURE OF A BROMOFLUORO ESTER, ULTRASOUND MEDIATED REFORMATSKY REACTIONS AND STEREOSELECTIVITY

A novel ring opening reaction of hexafluoropropylene oxide (HFPO) 1 wi th lithium bromide/zinc bromide and subsequent reaction of the resulti ng acyl fluoride with primary and secondary alcohols gave bromofluoro esters 2, 3, 4 and 7. Reaction of the corresponding acyl fluoride with wafer leads to acid 9 which on treatment with dehydroabietylamine 10 gave the diastereomeric salt 11. Resolution of 11 and subsequent hydro lysis and esterification reactions led to enantiomerically pure ester 12. Reformatsky. reactions with 2 were studied which gave the alcohols 6 and 9. A Reformatsky-reaction of 12 with formaldehyde afforded an a lcohol 13 which is indicated by NMR spectroscopy in the presence of a chemical shift reagent to have proceeded stereoselectively.