Description
Octafluorocyclopentene (C5F8), a "heavy" etching gas used in advanced semiconductor chip manufacturing processes, possesses the highest carbon count and the largest molecular weight among known fluorocarbon etching gases; its unique properties and molecular structure set it apart in the field of etching.
Chemical Properties
Octafluorocyclopentene (OFCP) is a versatile tetrafunctional fluorinated monomer capable of forming microporous polymers with 2 equivalents of dihydroxy aryl comonomer or with tetrafunctional A4 type comonomer at certain ratios thus enabling to tune the surface area of polymers.[1]
Physical properties
Clear colorless liquid
Uses
Octafluorocyclopentene, or perfluorocyclopentene, is mainly used for etching and cleaning semiconductors, and can participate in the preparation of organic photochromic materials. Octafluorocyclopentene is considered to be a competitive advantage as one of the next generation etching gases and the most attractive raw material for electronic devices. It may also be used in the synthesis of high-end dyes.
Reactions
Reactivity of the double bond: As an unsaturated alkene, the double bond can undergo addition reactions.
Electrophilicity: Octafluorocyclopentene can act as a poly-electrophilic reagent, participating in cascade substitution reactions to form complex macrocyclic compounds.
Reaction with phenols: Under mild conditions, it can undergo nucleophilic substitution reactions with phenols to yield fluorinated aryl ethers.
Hazard
Octafluorocyclopentene has an irritating odor; inhalation or skin contact can cause irritation to the respiratory tract, eyes, and skin; it releases toxic fluorides when exposed to high temperatures or combustion.
Synthesis
Synthesis route of octafluorocyclopentene:
Under the action of gas phase fluorination catalyst, octachlorocyclopentene and anhydrous HF are first halogen exchange reacted to produce 1, 2-dichloro-3, 3,4,4,5, 5-hexafluorocyclopentene, chloroheptafluorocyclopentene, etc. and then reacted with alkali metal fluoride in amide and sulfoxide solvent to produce octafluorocyclopentene.
References
[1] Parthiban, A., & Krishnan, R. (2016). Octafluorocyclopentene – A versatile tetrafunctional monomer for making tunable, high surface area, microporous ladder polymers. Journal of Fluorine Chemistry, 191, Pages 70-76.
https://doi.org/10.1016/j.jfluchem.2016.09.013
