Novel fluorocarbon peroxygen compound derived from difluorodioxirane, bis(fluoroformyl) peroxide and related compounds

Fluorinated peroxides are a potentially large and interesting class of compounds. They are high-energy oxidizers with remarkable stability compared to hydrocarbon analogous. Research in the preparation of fluorinated peroxides was initially driven by their potential application in rocket propellant technology. Today their use as initiators in the production of fluorinated polymers has made research on their synthesis and reactivity of interest. In this dissertation, the study on the chemistry of difluorodioxirane (the simplest perfluorinated peroxide) and Bis(fluoroformyl) peroxide (the simplest fluorinated diacyl peroxide) will be described.; Dioxiranes are powerful oxygen transfer reagents which have been studied extensively over the last twenty years. Difluorodioxirane is one of the most stable dioxiranes known. The first successful synthesis of difluorodioxirane was based on the reaction of its isomer fluorocarbonyl hypofluorite—FC(O)OF with OF in the presence of CsF. We have improved this method by using Cl ₂ and the new catalyst KHF₂. A novel reaction associated with difluorodioxirane is the reaction of difluorodioxirane with COF ₂ in the presence of CsF which forms CF₃OOC(O)F and the new compounds CF₃ O(OCF₂O)_nOC(O)F (n = 1∼3); 13C labeling shows that the difluorodioxirane undergoes ring opening at the O-O bond. This is very surprising result because of the attack of CF ₃O− on difluorodioxirane at oxygen and not at the more electropositive carbon. The reaction has been extended to prepare other fluoroformyl peroxy esters FC(O)OOR_f which are precursors to functionalized fluoroxy compounds. Fluoroxy compounds are very useful in the production of fuorovinyl ethers, a family of monomers suitable for the preparation of both crystalline and amorphous polymers.; Difluorodioxirane is also involved as an intermediate in other reactions. For example, the reaction of CF₂(OF)₂ with COF ₂ in the presence of CsF formed CF₃OOC(O)F in excellent to moderate yields. Our 13C labeling study indicates difluorodioxirane is probably an intermediate in the reaction.; Bis(fluoroformyl) peroxide FC(O)OOC(O)F is a highly reactive but easily prepared peroxide. Much of the chemistry of FC(O)OOC(O)F has been devoted to the elucidation of its reaction chemistry as a radical source. One of the more interesting early reactions of FC(O)OOC(O)F was the formation of fluoroformyl trifluoromethyl peroxide CF₃OOC(O)F and bis(trifluoromethyl) bis(peroxy)carbonate (CF₃OO)₂C=O in the presence of CsF. In our study of the chemistry of difluorodioxirane we reinvestigated this reaction and found two new compounds FC(O)OOCF₂OOC(O)F and 4,4-difluoro2,3,5,6-tetraoxacylohexanone. We proposed a new mechanism to explain the generation of the products. In order to synthesize new functionalized fluoroxy compounds, the reactions of FC(O)OOC(O)F with F₂ in the presence of several metal florides were also studied. We found FOCF₂OOC(O)F can be prepared by using KHF2 or CSHF₂ as a catalyst. FOCF₂OOC(O)F is an interesting example of a functionalized fluoroxy compound carrying the peroxide, fluorooxy and carbonyl function groups. Its reaction chemistry to other noval fluoroxy compounds such like FOCF₂OOH and (FOCF₂OO)₂C=O is discussed.