699-39-8

Usage

Uses

Used in Organic Synthesis:
1,2,3,4,5,5-Hexafluoro-1,3-cyclopentadiene is used as a reactive intermediate for the synthesis of various fluorinated organic compounds. Its high reactivity allows for the formation of a wide range of products, making it a valuable building block in the field of organic chemistry.
Used in Fluoropolymer Production:
1,2,3,4,5,5-Hexafluoro-1,3-cyclopentadiene is used as a monomer in the production of fluoropolymers. These polymers are known for their exceptional chemical resistance, thermal stability, and low friction coefficients, making them suitable for applications in the chemical, automotive, and aerospace industries.
Used in Pharmaceutical Industry:
1,2,3,4,5,5-Hexafluoro-1,3-cyclopentadiene is used as a key intermediate in the synthesis of certain pharmaceutical compounds. Its unique fluorinated structure can impart specific properties to the final drug molecules, such as improved bioavailability or enhanced metabolic stability.
Used in Material Science:
1,2,3,4,5,5-Hexafluoro-1,3-cyclopentadiene is used as a precursor in the development of novel materials with tailored properties. Its incorporation into various structures can lead to materials with enhanced performance in areas such as electronics, energy storage, and sensors.

Upstream product

• 2344-14-1 3H-heptafluorocyclopentene 
• 598-73-2 1-bromo-1,2,2-trifluoroethene 
• 19721-29-0 1,2,3,3-tetrafluorocyclopropene 
• 13222-45-2 1,1,1,5,5,5-hexafluoro-2,4-bis-trifluoromethyl-penta-2,3-diene 
• 771-61-9 2,3,4,5,6-pentafluorophenol 
• 1453-38-9 2,3,4,5-Tetrachlor-1,1,2,3,4,5-hexafluorcyclopentan 
• 123438-12-0 hexafluorobicyclo<2.2.0>hex-5-ene-2,2-diol 
• 562-19-6 1,2,3,4-tetrachloro-5,5-difluoro-cyclopenta-1,3-diene 
• 77-47-4 hexachlorocyclopentadiene 
• 2344-15-2 1,2,3,3,4,5,5-heptafluorocyclopentene 

Downstream Products

• 1482-03-7 1,2,3,4,7,7,-hexafluorobicyclo[2.2.1]hept-2-ene 
• 25222-21-3 2,2,2-Trifluoro-N-(1,4,5,6,7,7-hexafluoro-bicyclo[2.2.1]hept-5-en-2-ylmethyl)-acetamide 
• 1482-09-3 9,10-<1,2,3,4,5,5-Hexafluor-cyclopenten-(3)-diyl-(1,2)>-9,10-dihydro-anthracen 
• 1501-62-8 3,4,5,6,12,12-Hexafluor-tetracyclo<6.2.1.1^3.6.0^2.7>dodecadien-4.9 
• 1482-04-8 1,2,3,4,7,7-Hexafluor-5-vinyl-bicyclo<2.2.1>hepten-(2) 
• 1660-07-7 5,5'-Bis-<1,2,3,4,7,7-hexafluor-bicyclo<2.2.1>hepten-2-yl> 
• 1482-05-9 1,2,3,4,7,7-Hexafluor-bicyclo<2.2.1>heptadien-(2,5)-dicarbonsaeure-(5,6)-dimethylester 
• 17065-31-5 1,2,3,4,7,7-hexafluorobicyclo<2,2,1>hepta-2,5-diene 
• 559-40-0 octaperfluorocyclopentene 
• 911225-21-3 1,4,5,6,7,7-hexafluoro-2,3-diazabicyclo[2.2.1]hept-5-ene-2,3-dicarboxylic acid dimethyl ester 
• 12212-29-2 (C₅F₆)2Co₂(CO)4 
• 1482-08-2 Perfluor-tricyclo<5,2,1,0^2,6>deca-3,8-dien 

Relevant academic research and scientific papers

Extremely facile ring inversion and rearrangement in fluorobicyclo[2.1.0]pentanes

cis-1,2,3,4,5,5-Hexafluorobicyclo[2.1.0]pentane and 1,2,4,5-tetrafluorobicyclo[2.1.0]pentane have been synthesized from hexafluorobenzene. The former hydrofluorocarbon, which exists entirely in the endo configuration, rearranges to cis-1,2,3,3,4,5-hexafluorocyclopentene below room temperature (Ea = 21.9 kcal/mol, log A = 13.4). The latter undergoes degenerate ring inversion with extraordinary ease (ΔG? = 6.8 ± 0.2 kcal/mol at -55 °C). Density functional calculations indicate that significant bonding between the bridgehead carbons is retained in the ring inversion transition state. Analogous calculations predict for hexafluorobicyclo[1.1.0]butane a considerably lower barrier for ring inversion and more 1,3-bonding in the transition state.

MASS SPECTRAL STUDY OF THE PYROLYSIS OF TETRAKIS(TRIFLUOROMETHYL)ALLENE

Low-energy mass spectrometry and chromato-mass spectrometry have been used to show that major final products of the pyrolysis of tetrakis(trifluoromethyl)allene (TTA) are perfluoro-1,3-cyclopentadiene and hexafluoroethane, formed as a result of the thermal loss of two trifluoromethyl radicals.This indicates the lack of an interaction of the trifluoromethyl substituents with the cumulene bond ?-electrons.

Synthesis and Chemistry of Highly Fluorinated Bicyclohexenone

A series of highly fluorinated bicyclo-5-hexen-2-ones (3) and their hydrates (4) have been prepared in two steps from hexafluoro Dewar benzene (1).Photolysis of exo-3H-pentafluorobicyclo-5-hexen-2-one (3d) at low pressure in the vapor phase gave 1H-pentafluorocyclopentadiene (8), but in solution the principal product was pentafluorophenol (9).Under Favorskii conditions, exo-3-bromo- and exo-3-chloropentafluorobicyclo-5-hexen-2-one (3a and 3b) ring opened stereospecifically to 2-cyclobutenecarboxylic acids 17 and 29, respectively.Treatment of these ketones with tert-butoxide under aprotic conditions effected stereospecific cleavage to tert-butyl methylenecyclobutenecarboxylates 25 and 30.The acid (27) corresponding to 25 was obtained both from bromohydrate 4a and the acid 17, again stereospecifically, by reaction with lithium diisopropylamide.Flash vacuum pyrolysis of the hydrate (4c) of of hexafluorobicyclo-5-hexen-2-one at 300 deg C gave hexafluoro-2,4-cyclohexadienone (12), which decarbonylated at higher temperatures to yield hexafluorocyclopentadiene (13).Similarly, flash vacuum pyrolysis of 3-chloropentafluorobicyclo-5-hexen-2-one (3b) at 650 deg C gave a mixture of 1- and 2-chloropentafluorocyclopentadienes.

Reactions of 1,2,3,4,5-Pentafluorocyclopentadiene

The synthesis of 1,2,3,4,5-pentafluorocyclopentadiene (2) from 1,2,3,4,5-pentachloro-1,2,3,4,5-pentafluorocyclopentane (1) is closely investigated.Side-products are 1,2,3,4-tetrafluorocyclopentadiene (4) and 5-chloro-1,2,3,4-tetrafluorocyclopentadiene (5).Under UV irradiation, 2 isomerizes to give 1,2,3,5,5-pentafluorocyclopentadiene (6). 2 dimerizes forming a mixture of Diels-Alder products.This dimerisation is irreversible until 700 deg C.The hydrogen in 2 can be replaced by bromine forming 7. 2 adds Cl2, Br2, I2, and carbonylmetal hydrides.Also with the most stable salt Tl(+)C5F5(-) (8) the synthesis of a η5-C5F5 complex was unsuccessful.A modified synthesis of hexafluorocyclopentadiene (12) from hexachlorocyclopentadiene (9) is presented. 12 adds AsF5 forming c-C5F7AsF4 (13).With SbF5 no cation c-C5F5(+) (14) could be detected so far.

New Routes to Hexafluorocyclopentadiene and Related Compounds

Hexafluorocyclopentadiene (1) has been synthesized in two steps from pentafluorophenol (2) by fluorination followed by flash vacuum pyrolysis of the resulting hexafluorocyclohexadienones 3 and 4.Similar pyrolysis of 6-chloropentafluorocyclohexadienone (13) gave an equilibrium mixture of 1- and 2-chloropentafluorocyclopentadiene (15 and 16), presumably via the 5-chloro isomer.Flash vacuum pyrolysis of tetrafluoro-o-benzoquinone 17 yielded tetrafluorocyclopentadienone (20).Hexafluorocyclopentadiene was also prepared via a ring-expansion route which entailed cycloaddition (accompanied by rearrangement) of bromotrifluoroethylene to tetrafluorocyclopropene followed by reductive debromofluorination.