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Radical fluorination is a type of fluorination reaction, complementary to nucleophilic and electrophilic approaches. [1] It involves the reaction of an independently generated carbon-centered radical with an atomic fluorine source and yields an organofluorine compound .
This isotope is particularly advantageous due to its short half-life of approximately 109.8 min, its decay being 97% positron emission, its ease of production, and its energy being low (0.64 MeV). [1] Therefore, the radiofluorination procedure is incorporates the radioactive isotope of choice in order to create the images.
The direct fluorination of hydrocarbons with F 2, often diluted with N 2, is useful for highly fluorinated compounds: R 3 CH + F 2 → R 3 CF + HF. Such reactions however are often unselective and require care because hydrocarbons can uncontrollably "burn" in F 2, analogous to the combustion of hydrocarbon in O 2. For this reason, alternative ...
Radical fluorination in radical decarboxylative fluorination reactions, [10] in Hunsdiecker-type reactions where xenon difluoride is used to generate the radical intermediate as well as the fluorine transfer source, [28] and in generating aryl radicals from aryl silanes: [29] XeF 2 is selective about which
Electrophilic fluorinating reagents could in principle operate by electron transfer pathways or an S N 2 attack at fluorine. This distinction has not been decided. [2] By using a charge-spin separated probe, [3] it was possible to show that the electrophilic fluorination of stilbenes with Selectfluor proceeds through an SET/fluorine atom transfer mechanism.
C 6 H 13 CO 2 H + 2 SF 4 → C 6 H 13 CF 3 + 2 SOF 2 + HF. The formation of the trifluoromethyl derivative sometimes competes with formation of tetrafluoroalkyl ethers, which arise from the reaction between difluoromethyl cation and acyl fluoride. [11] [12] Sulfur tetrafluoride can be used to fluorinate polymers efficiently.
The species KHF 2 is relatively low melting, a good electrolyte, and an effective source of fluorine. The technology is sometimes called “CAVE” for Carbon Anode Vapor Phase Electrochemical Fluorination and was widely used at manufacturing sites of the 3M Corporation. The organic compound is fed through a porous anode leading to exchange of ...
The fluorinase catalyses an S N 2-type nucleophilic substitution at the C-5' position of SAM, while L-methionine acts as a neutral leaving group. [ 5 ] [ 6 ] The fluorinase-catalysed reaction is estimated to be between 10 6 [ 6 ] and 10 15 [ 7 ] times faster than the uncatalysed reaction, a significant rate enhancement.