DE1568841B - Process for the preparation of new aromatic compounds which contain perfluoroalkyl groups in the nucleus - Google Patents

Description

1 2

It is known that tetrafluoroethylene is analogous to some fluoropropene, the perfluoroolefin

aromatic compounds, e.g. B. Benzene and certain reactions, and perfluoropropyl groups are on

substituted benzenes, the aromatic nuclei are bound in the presence of nonionics, but is generally

Catalysts, such as cobalt carbonyl, mean the extent to which perfluoropropyl groups can add

to z. B. to give fluoroalkylbenzenes in which the 5 achieved substitution is less than that by Per-

Fluoroalkyl side chains terminal hydrogen atoms fiuoräthylgruppen reached.

have, but must as starting material The products of the process according to the invention

Aromatic compounds used at least range from liquids with boiling points below

1 hydrogen atom bound to the core, 150 ⁰ C to solids with melting points above

and furthermore one hydrogen atom for each molecule must be in the range of 200 ° C. Some of these are thermally stable liquid

Tetrafluoroethylene, which is added to the core, on items suitable for use as a lubricant,

be bound to the core. Coolants and heat transfer media are suitable. Other

It is according to the invention a process for are valuable intermediates for the preparation of

Production of new aromatic compounds, compounds whose molecules are highly fluorinated

which contain perfluoroalkyl groups in the nucleus, are present and contain reactive groups, and accordingly

beaten, which is characterized in that have valuable features such. B. surface-active

one hexafluorobenzene, pentafluorochlorobenzene, tetra properties.

fluorodichlorobenzene, octafluorotoluene, decafluorodiphe- The following examples illustrate the invention,
nyl, octafluoronaphthalene or decafluoroanthracene with.
Tetrafluoroethylene or hexafluoropropene as a counter example!
wart of alkali fluorides or tetraalkylammonium 70 g of tetrafluoroethylene were converted into a suspension of fluorides as ionic catalysts, depending on the starting materials used by 5 g of dry potassium fluoride in 50 g of hexafluorine at temperatures up to benzene and 150 ml of dry dimethylformamide, 250 ° C in a closed vessel. which were contained in an equipped with a stirrer auto-tetrafluoroethylene and hexafluoropropene add 25 klav, distilled. The autoclave was thus heated to 155 ° C on the aromatic compound mentioned and held at this temperature for 6 hours with no hydrogen atom bonded to the core, during which time the pressure from 33.7 to contained, and give derivatives in which full - 2.81 kg / cm ² fell. The autoclave was cooled and the permanently fluorinated side chains which had no terminal contents filtered to contain 6 g of a solid product bound to the core hydrogen atoms, which were in water, dimethylformamide and benzene. was insoluble, and contained only carbon and fluorine The reaction temperature is expediently 20 to and melted at 200 to 210 ° C and an empirical 250 ° C, preferably 50 to 150 ° C. Formula of about C ₆ F ₆ (C ₂ F ₄ ) ,, had. The recrystallization medium It is usually advisable to use a liquid reaction of this solid substance produced from hexafluorobenzene, but this is not a solid with a melting point of 204 ° C, the mass of which is required. Suitable reaction media are the dimethyl spectrum showed that it was C ₆ (C ₂ F ₅ ) ₆ , perfluorohexaethylformamide, dimethylacetamide, tetramethylene sulfone, benzene.

N-methylpyrrolidone, hexamethylphosphoramide and the concentration of the filtrate from the recrystallization diethylene glycol dimethyl ether. gave a solid with a lower melting point, the aromatic starting compound hexa- 40 point, which corresponded to _{C e} F (C ₂ F _s ) _5.

is fiuorbenzol, the products of the reaction possess the The liquid filtrate was poured into water,

general formula washed, separated and dried over anhydrous ma-

/ f, c _{Λ K} /-.-p / T ¹ T? ^ dried magnesium sulfate and then fractionally distilled

C ₆ F "-" (C ^) "or C ₆ ^ _e -" (. C ₃ t < ₇ ) ", which _{covers a range of} perfluoroethylbenzenes,

where η is an integer from 1 to 6. ⁴ S pc ^ c \ pü ^ i: ^ η r (^ c \ α η-c rr-τ: \

If the aromatic starting compound is ^c <^^ C ₂ F * >> M ^ 4I ₁ W ^ sh, W "3 (C ₂ J ^ ₃ and c ₆ t < ₂ (e ₂ t < ₅ ) _i;

Is fluorochlorobenzene, it is not possible to more than revealed. Your empirical formulas were made through

a limited number of perfluoroalkyl groups determined by elemental analysis, and their structure by

because the mass spectrographic analysis and NMR measurements bound to the benzene nucleus

Chlorine atoms activated by the perfluoroalkyl groups are activated. The measurements of the nuclear magnetic

become and tend to be removed by themselves. Resonance also showed that the main iso-

In pentafluorochlorobenzene z. B. it is not possible to meren of C ₆ F ₄ (C ₂ Fg) ₂ 1,4-perfluorodiethylbenzene, of

to introduce more than three perfluoroethyl groups without C ₆ F ₃ (C ₂ Fs) ₃ 1,3,4-perfluorotriethylbenzene and of

To remove chlorine and to deactivate the catalyst were C ₆ F ₂ (C ₂ Fg) ₄ 1,2,4,5-perfluorotetraethylbenzene,
four. In a corresponding way one can with Tetra- 55

fluorodichlorobenzene not more than two perfluoroethyl ^The following yields were obtained:

introduce groups without loss of chlorine. C ₆ F ₅ (C ₂ F ₅ ) about 10 g

When tetrafluoroethylene and octafluorotoluene as C ₆ F ₄ (C ₂ Fj) ₂ about 12 g

aromatic starting compound can be used, C ₆ F ₃ (C ₂ F ₅ ) ₃ about 12 g

the products have the general formula 60 C ₆ F ₂ (C ₂ F ₅ ) ₄ about 5 g

PF ipp ^ rp C ₆ F ₁ (C ₂ F ₅ ) ,, about 2 g

W, Γ β — rtlVa ^ 5) 11S- ^ Γ ₃ ,

where η is an integer from 1 to 5, and when the B is ρ ie 1 2

aromatic starting compound Decafluordipher.yl

they have the general formula 65 100 g tetrafluoroethylene, 50 g hexafluorobenzene, 3 g

_r λ- ρ \ dry cesium fluoride and 100 ml dry di-

^ ΐΐΤιο-ηΚ ^ ύη, methylformamide were mixed with each other at 100 ° C in

where /; is an integer from 1 to 10. When hexa- a stirred autoclave is heated for 4 hours, after which the

Claims (1)

3 4 Pressure had dropped by 10.5 kg / cm ^2. The autoclave The main component C ₆ (C ₂ F ₅ ) ₅ CF _{: J} was in was cooled and the products were obtained in an amount of 12 g. Example 1 treated way, what 15 g. . unchanged hexafluorobenzene and 30 g of mixed example ten perfluoroalkylbenzenes, from C ₆ F ₅ (C ₂ F ₅ ) to 5 60 g tetrafluoroethylene, 40 g pentafluorochlorobenzene, Reached C ₆ (C ₂ Fg) ₆ . 3 g dry cesium fluoride and 100 ml dry ■ jiijAi-'ui dimethylformamide were mixed together at 110 ° C in The following yields were obtained: _{heated in a stirred autoclave for 4 hours! while} C ₈ F ₅ (C ₂ F ₅ ) about 2 g which time the pressure from 28.1 kg / cm ² to 8.44 kg / C ₆ F ₄ (C ₂ Fj) _{2 fell} about 5 g 10 cm ² . The autoclave was cooled and the C ₆ F ₃ (C ₂ F ₅ ) ₃ about 5 g content poured into water. C ₆ F ₂ (C ₂ Fj) ₄ about 8 g. The lower layer was separated, with water C ₆ F (C ₂ F ₅ ) ₅ washed only a trace, dried and distilled, which gives 20 g un- C ₆ (C ₂ F ₅ ) _e about 10 g of modified pentafluorochlorobenzene and a fraction i5 of higher boiling point resulted. Fractionation Example 3 of the latter by means of gas phase chromatography gave 15.5 g of C ₆ F ₄ Cl (C ₂ F ₅ ), 8.2 g of C ₆ F _S C1 (C ₂ F _S ) ₂ and 20 g of tetrafluoroethylene, 30 g of hexafluorobenzene and 1.5 g of C _e F ₂ Cl (C ₂ F ₅ ) ₃ . These formulas and structures 2 g tetraethylammonium fluoride were massenspektrograbei 15O ⁰ C were mixed together by elemental analysis, heated for 6 hours in a stirred autoclave, 20 chromatographic analysis and NMR after which the pressure to 21 kg / cm ² had dropped by the measurements. The spectra confirmed. The reaction mixture was cooled, and attempts to make compounds with the products were distilled, which resulted in 15 g of unchanged hexafluoro- more than three pentafluoroethyl groups in benzene and 25 g of mixed perfluoroalkylbenzenes.
Hg to a crystalline solid from F.. . . = 205 ⁰ C were sufficient. These liquids and solids - Example 6 Substances were described in Example 1 as 30 g of hexafluoropropene, 30 g of hexafluorobenzene, 100ml Perfluoräthylbenzole identified by their heated retentate dry dimethylformamide and 2.5 g Caesiumtionszeiten in the gas-phase chromatography, their were 3 ° fluoride together in a stirring autoclave mass spectra and its NMR spectra compared for 4 hours at 110 ⁰ C. The reaction was. mixture was then cooled and poured into water The following yields were obtained: poured. The lower layer was separated and distilled, which gives 20 g of unchanged hexafluorobenzene, 9ξ V · · · · fj ™ \ ll 35 10.2 g perfluoropropylbenzene C ₆ F ₅ (C ₃ F ₇ ) and 5.5 g % ξ * C ₂ F ₅ ) about 10 g of perfluorodipropylbenzene C ₆ F ₄ (C ₃ F ₇ ) resulted. ^ e * 4 (Ls ₂ F5) 2 about JLd g C ₆ F ₃ (C ₂ Fs) ₃ about 8g Example 7 f s> 4 ^{about 12} S 20 g decafluorodiphenyl, 100 ml dry dimethyl y) _s ^about * ^s 40 formamide, 3.0 g cesium fluoride and 50 g tetrafluorine ₅ ),) 6 g of ethylene were mixed together in a stirred autoclave Fixed torrent heated at 120 ° C for 4 hours. The main product Example 4 of the reaction was a perfluoroethyldiphenyl, which in 150 ⁰ C melted, and through the elemental analysis 20 g of octafluorotoluene, 50 ml of dry diethylene- 45 and the mass spectrographic analysis and the glycol dimethyl ether and 2 g of dry cesium fluoride measurement of the NMD spectra proved to be C ₁₂ F ₄ (C ₂ F ₅ ) _e , were placed in a dry autoclave, and further If smaller amounts of C ₁₂ F ₂ (C ₂ Fj) _{3 were} then 60 g of tetrafluoroethylene were distilled in. Der and C ₁₂ (C ₂ F ₅ ) _{10 are} formed.
Autoclave was heated to 1O ⁰ C and _p of the content.
touched. Within 6 hours the pressure of 50 installment claims fell:
23.2 kg / cm ² to 3.52 kg / cm ² , and the reaction was then terminated in the process of producing new aromatics. The contents of the autoclave were identified and distilled in compounds that were poured into perfluoro-water with a stable core and the lower layer contained separated alkyl groups. The distillate was drawn in the gas phase by subjecting hexafluorobenzene, penta-chromatography to it in order to separate it into its fluorochlorobenzene, tetrafluorodichlorobenzene, octahedral components; Spectrographic analysis found that they contained all or hexafluoropropene in the presence of alkali five possible pentafluoroethyl perfluorotoluenes of fluorides or tetraalkylammonium fluorides as C ₈ F ₄ (C ₂ F ₅ ) CF ₃ to C _e (C ₂ F ₅ ) ₅ CF ₃ . Their 60 ionic catalysts, depending on the structures used, were confirmed by measuring the NMR starting materials at temperatures of up to 250 ^° C. spectra. implemented in a closed vessel.