Solid phase direct fluorination

[摘要] In 1970, solid phase direct fluorination, using modern flow control techniques, was pioneered in the laboratories of John Margrave. Modern direct fluorination is rooted in these developments.The direct fluorination of polycyclic aromatic hydrocarbons (pyrene, coronene, perylene, etc ...) and several commercially available polymeric materials (polyethylene, poly (vinyl fluoride), poly (vinyl chloride), and polystyrene) are here reexamined. The previously unreported direct fluorination of the new polymer, polycyclopentadiene, has been carried out. The direct fluorination of the natural materials; coal and gilsonite; along with man-made petroleum coke affords a rapid, direct synthesis of potentially useful perfluorocarbon compound mixtures. The tentatively successful exhaustive fluorination of these starting compounds have been carried out using longer reaction times, and heated reaction vessels.By using extensive mass spectral, FT-IR, and differential scanning calorimetry data, a more complete description of the course of polymer fluorination is made possible. The vacuum pyrolysis mass spectra of polymers of varying fluorine contents are now reported. Several characteristic stages of fluorination can be identified.The superior thermal stability of fluorinated polymers is demonstrated using differential scanning calorimetry. DSC curves were secured for polymers in all stages of fluorination and are compared with those of the respective starting materials.Chemical reactions of an active carbon derived ;;CFX;; are here reported. Slurries of the compound were contacted with a variety of nucleophilic reagents, most notably, alcoholic KOH and an assortment of amines. The products were examined using diffuse reflectance fourier transform infrared spectroscopy (DRIFTS), electron spectroscopy for chemical analysis (ESCA), and elemental analysis. The susceptibility of the substance to nucleophilic attack was confirmed. Defluorination and rearomatization were the most readily apparent results. Hydroxy groups were detected in the products of the KOH/ethanol reactions using ESCA.

[发布机构] Rice University

[效力级别] chemistry