Patented Nov. 19, 1946 , 2,411,158 UNITED STATES PATENT orncs 2,411,158 SATURATED POLYFLUORO CARBONYL COM POUNDS AND THEIR PREPARATION William Edward Hanford, Easton, Pa., assignor to E. I. du Pont de Nemours 8: Company, Wilming ton‘, DeL, a corporation oi Delaware No Drawing. Application April 23, 1943, 1 Serial No. 484,298 8 Claims. (Cl. 260—-‘586) 2 This invention relates to the preparation of . A preferred form of the invention may be car ?uorinated organic compounds and to new or ‘ ganic ?uorine compounds. More particularly, the invention comprises a new process for the prep ried out by reacting tetra?uoroethylene with a saturated organic carbonyl compound containing at least two carbon atoms and containing only aration of poly?uoro carbonyl compounds and in cludes new chemical products consisting of sat~ carbon, hydrogen and oxygen atoms, preferably urated organic carbonyl compounds containing . one or more polyfluoroethylene groups per mole- - in a closed system and in the presence of a cata lyst. Saturated organic poly?uoro carbonyl com pounds are obtained containing one or more . tetra?uoroethylene units per molecule of car Heretofore the only practical method for pre 10 bonyl compound. These resulting products may , paring ?uorine-containing organic compounds be represented by the general formula cule. has been to replace chlorine with ?uorine by means of various inorganic reagents, such as hydrogen ?uoride, silver ?uoride, antimony ?uo-‘ where n is a positive integer in'the range 1 to rides, mercuric fluoride-and other metallic ?uo 15 about 25, and Z is the complementary portion of rides. Such processes yield mixtures of inert prod - the carbonyl reactant, being a monovalent sat ucts, are very restricted in application and in volve considerable expense. It‘ has also previously been proposed to pro urated organic radical consisting solely of car bon, hydrogen and oxygen atoms and containing duce organic ?uorine compounds by the reaction 20 of ?uorine with various organic materials. Prior investigations have shown that this reaction of at least two carbon atoms and at least one car bonyl group. I The polyfluoroethylenes suitable for use in this invention may be represented by the general for mula CX2=CX2 where one X is selected from ?uorine is extremely energetic and generally causes pyrolysis of the organic material, result the group consisting of hydrogen and halogen ing in the formation of carbon, tar or other un 25 and the other three X’s are halogen of which at desirable carbonaceous decomposition products. least two are ?uorine. It is an object of this invention to provide a new process for the preparation of saturated or ganic polyfluoro carbonyl compounds. Another object of this invention is to obtain new compo sitions of matter consisting of ?uorinated or Saturated organic carbonyl compounds suit able for use in this invention are free of ethylenic and acetylenic linkages, contain at least two car 30 bon atoms and at least one 0 ganic compounds containing the carbonyl func tional group. Still another object is to prepare ?uoro carbonyl compounds which have outstand group and consist of only carbon, hydrogen and ing thermal and chemical stability. A further ob ' oxygen atoms. These saturated organic carbonyl ject is to provide a relatively simple and inex compounds may be acyclic or cyclic, including pensive process for readily preparing saturated aliphatic, alicyclic,‘ aromatic and heterocyclic sat organic carbonyl compounds containing one or urated organic carbonyl compounds consisting more poly?uoroethylene groups per molecule. _ A ' solely of carbon, hydrogen and oxygen atoms‘. still further object is to obtain saturated organic 40 The general formula ZH may be used-to repre ?uorinated carbonyl compounds possessing many sent these organic carbonyl compounds where Z novel and useful properties. Other objects will is the complementary portion of the carbonyl re appear hereinafter. actant, being a monovalent saturated organic These objects are accomplished by reacting a radical consisting solely of carbon, hydrogen and poly?uoroethylene containing at least three halo 45 oxygen atoms and containing at least one gen atoms of which at least two are ?uorine with a saturated organic carbonyl compound contain- T 0 % .__c_ ing at least two carbon atoms and containing only carbon, hydrogen and oXygen atoms.’ This re group and at least two carbon atoms. action produces saturated organic polyfluoro car 50 The saturated organic ?uorinated carbonyl bonyl products containing at least one poly?uoro compounds prepared in accordance with this in ethylene unit per molecule of carbonyl reactant. vention may be represented by the general for The pre?x “poly” as used herein refers to the mula H(CX2CX2)nZ where n is a positive integer number of ‘?uorine atoms in the fluoroethylene in the range 1 to about 25, one X is selected from molecule and not to polymeric materials. the group qqnsisting of hydrogen and halogen, the I 2,411,158 4 number of (C&CX2) groups in the compound and is a positive integer in the range 1 to about other three X's are halogen of which at least two are ?uorine, and Z is the complementary por tion of the carbonyl reactant being a monovalent saturated organic radical consisting solely of car bon. hydrogen and oxygen atoms and containing 25, m is the number of (CXzCXr) groups con tained in V and is an integral number in the range 0 to about 25 but is not greater than n, and V is a monovalent saturated organic radical at least one containing m(CXzCX2) groups and at least 1' ~ 10 0 carbon atoms exclusive. of those present in the (0&CX2) portion of the radical and at least one % group and at least two carbon atoms. In the preferred products n is a positive integer in the 10 0 % __C.... range 1 to 15. group but otherwise consisting solely of carbon, It is also possible to obtain products in which all of the ?uoroethylene units are not necessarily 15 hydrogen and oxygen atoms. The method for carrying out the reactions var connected together and which may be represent ies to some extent with different types of car ed by the general formula bonyl compounds, but the usual procedure com prises placing a given amount of a saturated or where n'is a positive integer in the range 1 to about 25, m is not greater than n and is an in tegral number in the range from 0 to about 25, one X in each parenthesis is selected from the group consisting of hydrogen and halogen, the other three X’s in each parenthesis are halogen of which at least two are ?uorine and Y is the 25 ganic carbonyl compound and of a poly?uoro ethylene, such as tetra?uoroethylene, with or without a catalyst in a high-pressure reaction vessel and then closing and heating to the de sired reaction temperature while mechanically agitating the reaction vesse1 for several hours. In order to prepare the low molecular weight complementary portion of the carbonyl reactant, products which are characteristic of this inven tion, it is usually desirable to carry out the reac tions under pressure at elevated temperatures. sisting solely of carbon, hydrogen and oxygen The temperature at which thereaction is ef atoms and containing at least one 30 fected may be varied over a wide range, depend 0 ing largely upon the nature of the reactants’, the % being a divalent saturated organic radical con _.C_.. group and at least two carbon atoms. It is to be understood that the units in parentheses cor respond to the particular ?uoroethylene which is employed in the reaction, although tetra?uoro ethylene is the preferred reactant. The sum to catalyst, the resultsdesired, and other conditions of the reaction. However, the temperature should be below that at which decomposition or pyrolysis 35 of either the reactants or products occurs. No appreciable reaction is obtained below 50° C. and it is usually necessary to heat the reaction mix ture to 75° C. or higher in order to obtain a tal of the atoms other than the ?uoroethylene substantial reaction in a reasonable time. The units is equivalent to only one molecule of the 40 preferred temperature range is ‘IS-250° C., but original organic carbonyl compound. Thus the higher temperatures up to approximately 350° C. saturated organic carbonyl compounds in this in are sometimes desirable. ' vention react with a ?uorocarbon, such as tetra A series of products are usually obtained which ?uoroethylene, to yield a series of monomeric sat vary from liquids to solids depending upon the. urated organic poly?uoro carbonyl compounds. carbonyl compound and the number of poly?uoro The following speci?c example is given to fur ethylene units per molecule of product. In gen ther illustrate the invention: eral, the liquid products are compatible with the common organic solvents, whereas the low mo 0 50 lecular weight solid products have limited solu bility or are insoluble in most solvents. The invention is further illustrated by the fol lowing examples in which the parts are by weight ' 55 unless otherwise speci?ed. This product may react with additional tetra ?oroethylene as illustrated below: Further reaction with tetra?uoroethylene may also occur. Thus the most general formula rep resenting the new saturated poly?uoro carbonyl products is H(CX2CX2)n—1n—V where one X is selected from the group consisting of hydrogen and halogen and the other three X’s are halogen of which at least two are ?uorine, n is the total Edcample' I A silver-lined autoclave was flushed with nitro-v gen and charged with 146 parts of freshly dis tilled methyl formate and 1.5 parts of benzoyl per oxide. ‘Aftér pressuring with tetra?uoroethylene to_350 lbs/in.2 at 110° 0., the autoclave was closed and heated with agitation for 8.5 hours at 110° C. The reaction mixture was steam distilled to yield (35 .4 part of steam-volatile solid melting at about 100° C. and 7.2 partsvof non-steam-volatlle solid melting at about 250°-260° C. . F . v . . Analysis of nonsteam-volatile solid melting at about 250°-260° 0.. Calculated for CILHIFMOI ..................... __'_' ..... -. ...... _. Per cent 69. 38 _ 69. 1 \ Average ratio O H (mm/Hoooom Per cent Per cent 25. 81 0. 86 ____________________ __ 25. 45 0.61 6/1 2,411,158 5 . Example II volatile products and 6 parts of waxy nonsteam A mixture of 150 parts of ethyl propionate and 1.5 parts of benzoyl peroxide was‘ reacted with volatile solid melting at about 210° C. were ob tamed tetra?uoroethylene under 350 lbs./in.=.I pressure at Emmgle VII 110° C. for 9 hours as described in Example I. b A mixture of 150 parts of ethylene glycol di Steam distillation and removal of the unreacted ethyl propionate gave about 6 parts of steam-vol- acetate, 1.5 parts of benzoyl peroxide and 50 parts of tetra?uoroethylene was reacted in an auto atile liquid products and '7 parts of greasy non- . clave at 110° C‘. for 8 hours. steam-volatile solid products. There was obtained 1.3 parts of steam-volatile solid melting at about Analysis 01' greasy nonsteam-volatile solid products ...... ._ Calculated I01‘ CoHmFsO: ------------------------------- -_ F C Per cent 45. 58 50._3 Per cent 40. 08 ' 35. 6 ' The Solid Products exhibited good lubricating A E i (omoygfli-igforstooolm Per cent 3. 72 __________________________ __ 3. 29 2/1 99° C. and 5 parts of nonsteam-volatile solid melt properties. 20 ing at about 250°-255° C. Example III E m 1 VI" A mixture of 150 parts of glacial acetic acid and x?‘ p e 1.5 parts of benzoyl peroxide was reacted with A mixture of 150 parts of cyclohexanone and tetra?uoroethylene under 350 lbs./in.2 pressure at 1.5 parts of lauroyl peroxide was reacted with tet 110“ C. for 9 hours. Steam distillation of the 25 ra?uoroethylene under 350 lbs/in.2 pressure at reaction mixture yielded?parts of nonsteam-vol110° C. for 8.5 hours. There was obtained 10 atile solid melting at about 260°-285° 0. parts of steam-volatile liquid products which were A ti F l 0 I H . was tea]. Per cent 65.03 Analysis of nonsteam-volatile solid melting at about 260°—285° C. Calculated for CwHrFmoz ..................................... ._ Per cent 27. 32 66. 1 Example IV . 26.1 Per cent 0. 61 ____________________ __ 0. 87 4/1 ‘heavier than water and could be separated by on repeatingExamme In using 150 parts of fractional distillation into various fractions cor propionic acid instead of glacial acetic acid, 2.4 40 respondmg to the 1/1 and hlghel‘ tetra?uoroeth parts of steam-volatile water-insoluble solid . melting at about 45°-50° C. and 8 parts of non steam-volatile solid melting at about 225° C. were obtained. ylene/cyclohexanone reactlon Products Emmple IX The products were readily soluble in dilute sodium hydroxide and alcohol. ’ 45 A mixture of 140 parts of methyl ethyl ketone. . F ‘ ' Analysis oisteam-volatile solid_.___' ___________________________ __ H Per cent 56.22 Per cent 27. 74 55.4 30. 65 2.19 66.13 26. 83 1.56 66. 2 27- 2 1. 05 Calculated for C7H5F5oz ________________________ ___-Analysis of nonsteam-volatile solid. _______________ __ 0 _-_ 0810111812611 for 01311915300: _____________________________________ __ Example V A t.’ m?‘it‘f?iéé‘tn Per cent 1.78 ~ ____________________ __ 2/1 ____________________ _ 5/1 1.5 parts of benzoyl peroxide and 50 parts of . On repeating Example II usmg 1000 lbs./in.2 tetra?uoroethylene was ‘ reacted 8.5 hours at o tetra?uoroethylene pressure instead of 350 no _Th_ere was obtamed 4 parts of Steam‘ 1bs_/in.2, parts of Steam_volatile products Volatile products heavier than Water and and 35 parts of nonsteam-volatile granular 501141 60 7.1 parts of non-volatile solid products melting at 'were obtained. about 230° C. . F Average ratio (C1FOIG2H5COOC2H5 Per cent Analysis of nonsteam-volatile granular solid. Calculated f0!‘ C?HmF?Qz ................ __ 65. 03 64- 9 __________________________ __ (ill Example VI ' Example X A mixture of 150 parts'of diethyl malonate and 1.5 parts of benzoyl peroxide was reacted with A mixture of ‘155 parts of acetic anhydride, 1.5 parts of benzoyl peroxide and 50 parts of tetra tetra?uoroethylene under 350 lbs/in.2 pressure - ?uoroethylene was reacted 9.5 hours at 110° C. at 110° C. for 9hours. About 1.5 parts of steam- 75 There was obtained .5 part of steam-volatile 2,411,158 7 8 liquid product and 15.4 parts of nonsteam volatile solid products. pentaacetate, sucrose octaacetate and cellulose acetate; and polyvinyl acetate. F - Analysis of steam-volatile liquid products..Calculated for C'HQFIO‘ .................. -_ Ratio (O,F4)/(OH;CO),0 Per cent 45-02 50- 3 .......................... __ 2/1 Example XI 10 It is often desirable to use a catalyst, although a catalyst is not always necessary. A wide variety A mixture of 150 parts of methoxyethyl of catalysts are operable including organic and methoxyethoxy-acetate, 50 parts of tetra; inorganic peroxygen compounds, alkaline cata ?uoroethylene and 1.5 parts of benzoyl peroxide lysts, and various acid type catalysts. The per was reacted 10 hours at 110° C. There was ob tained 1.5 parts of steam-volatile liquid products 15 oxygen type catalysts are preferred for use in this invention and examples of them are diacyl heavier than water and 15.2 parts of steam volatlle oil heavier than water which on frac peroxide, benzoyl peroxide, lauroyl peroxide, 111325‘ °-=1.3741, had the following composition: catalysts for use in this invention are borax, ethyl peroxide, sodium peroxide, hydrogen tional distillation yielded products with increas peroxide, barium peroxide, oxygen, ozone, air ing percentage of ?uorine with increase in boiling point. Fraction distilling at 125°-139° C./1 mm., 20 and ammonium persulfate. Examples of alkaline Ratio F O H ' (cam/08111.05. Analysis of fraction distilling Per cent Per cent Per cent at USP-139° C./l mm ______ __ Calculated for CHHNFHQL--. 44. 66 33. 14 3. 85 __________________ __ 46.3 34.15 3.25 3/1 Among the poly?uoroethylenes which are ap plicable in this invention are tri?uorochloro ethylene, di?uorodichloroethylene, bromoethylene and tri?uoroethylene. ' 30 disodium phosphate, sodium alcoholate, hy tri?uoro drazine, hydrazine salts, trimethylamine oxide, hexachloroethane-trimethylamine oxide, hexa However, chloroethane, hexachloroethane - borax and peroxide-,borax. Among the acid type catalysts poly?uoroethylenes containing three ?uorine atoms react more readily than the di?uoroethy 35 which may be used in this invention are Friedel Crafts type catalysts, zinc chloride and phos ‘ Tetra?uoroethylene is particularly pre lenes. ferred as it reacts the most readily. The preferred saturated organic carbonyl compounds are those containing a single ' phoric acid. The proportion of catalyst may vary within‘ relatively wide limits depending largely upon the ' 40 nature of the reactants and the products desired. Although ef?cient reaction may be effected with _._C_.. out the use of catalysts, it is generally preferred group per molecule. Ketones are a particular to employ a catalyst in this invention. Further preferred class of compounds foruse in this in more, the use of small amounts of catalyst're vention. However, the invention is applicable to 45 duces the temperature, time and cost'of opera- ' other saturated organic carbonyl compounds tion. Highly desirable results may be obtained 0 H ‘ containing at least two carbon atoms and con with the use of an amount of catalyst corre taining only carbon, hydrogen and oxygen atoms, such as aldehydes, including for example, sponding to about .001 to 10.0% by weight of the reactants employed. Advantageous results are acetaldehyde, propionaldehyde, n-butyraldehyde, 50 also sometimes obtained by using a combination isobutyraldehyde, heptaldehyde and lauralde of catalysts. hyde; ketones, including for example, acetone, Although a mixture of saturated organic car methyl ethyl ketone, methyl propyl ketone, bonyl compounds may be employed in this inven diethyl ketone, methyl isobutyl ketone, methyl tion, it is preferable to use a single saturated or tert.-butyl ketone, diisopropyl ketone, methyl 55 ganic carbonyl compound.‘ It is also preferable that the carbonyl compounds not be contami nonyl ketone, laurone, stearone, cyclohexanone and acetophenone; carboxylic acids, including for nated with other type organic compounds. Gen example, acetic, propionic, isobutyric, pivalic, erally a relatively large molar excess of the car bonyl reactant is used as compared to the more caprylic, lauric, stearic, adipic and sebacic acids; carboxylic acid anhydrides, such as acetic, 60 expensive poly?uoroethylene in order to prepare propionic, succinic and glutaric anhydrides; and esters of carboxylic acids, including for example, methyl formate, ethyl acetate, methyl propionate, methyl isobutyrate, ethyl butyrate, lauryl acetate, phenyl acetate,‘ diethyl oxalate, diethyl malonate; diethyl .succinate, diethyl adipate, dimethyl sebacate, methylene diacetate,. ethylene glycol low molecular weight products. However,_the de sired products may often be obtained by using a relatively small amount of the organic carbonyl compounds since the ratio of- poly?uoroethylene 65 units per unit of ‘carbonyl compound in the prod ucts varies' from 1 to about 25 depending upon the conditions. Usually the molar ratio of carbonyl compound to poly?uoroethylene in the reaction diacetate, ethyl benzoate and ethyl furoate. Of the aromatic compounds, those containing an mixture may vary from .04 to 20 but it is prefer aliphatic radical such as acetophenone, phenyl 70 able to work in the range .1 to 10 in order to ob acetate and ethyl benzoate are preferred as they tain the low molecular weight products which react more readily. Carbonyl compounds of are characteristic of this invention. higher molecular weight which are operable in It will be understood that the operating condi tions may vary widely depending upon the na the process of this invention include the esters of mono-, di- and polysaccharides such as glucose 76 ture of the compounds being reacted and also. 9,411,158. upon the results desired. The time required for carrying out the reactions may vary from a few minutes to several days depending upon the na ture of the reactants and the other operating con ditions such as temperature, pressure and cata lyst. ' The process may be operated continuously or intermittently. The reaction may be carried out in a closed system or the reaction may be car 10 bonyl products of this invention are useful as . lubricants since they have outstanding thermal and chemical stability. This invention is particularly advantageous in ' that it affords a safe, ?exible, practical and eco nomical process for producing highly ?uorinated saturated organic carbonylcompounds. One of the advantages of this invention is that the proc ess may be operated with none or a relatively ried out in the vapor phase by mixing the vapors 10 small amount of catalyst and the reaction pro of the organic carbonyl compound and poly ceeds smoothly and easily without undesirable ?uoroethylene and passing the mixture of vapors side reactions. ‘ through a hot reaction tube which if desired may As many apparently widely different embodi contain a catalyst. The reaction may be carried out under subatmospheric, atmospheric, or su 15 ments of this invention may be made without departing from the spirit and scope thereof, it is peratmospheric pressure in the range of .1 to to be understood that I do not limit myself to the 1000 atmospheres. The preferred pressure range specific embodiments thereof except as de?ned is 1 to 200 atmospheres. in the appended claims. Although there is no objection to the presence I claim: , of small amounts of water in carrying out the 20 1. The process for obtaining a mixture of tet process of this invention, it is preferable that the ra?uoroethyl carbonylic compounds which com reaction be conducted under substantially anhy prises heating tetrafluoroethylene with a satu drous conditions. However in certain instances, rated organic compound of at least two carbon the presence of water may be advantageous to atoms containing only carbon, hydrogen and oxy help dissipate the heat of the reaction. 25 gen selected from the class consisting of aliphatic The reactions may be carried out in any suita and cycloaliphatic acids, esters and ketones, the ble reaction vessel, such as stainless steel, iron, mole ratio of said saturated carbonylic compound silver, aluminum and other metals and alloys to said tetrafluoroethylene being from .1 to 10, which are capable of withstanding heat and pres said heating being effected in the presence of a sure. The reaction is preferably carried out with agitation, although agitation is not always. nec 30 peroxygen catalyst at a temperature within the essary. range of from 50° C. to 350° C. . The present invention is useful for the produc tion of a wide variety of organic ?uoro-substi tuted carbonyl compounds. Although it is under stood that usually a mixture of compounds with varying ratios of ?uoroethylene units per car bonyl molecule is obtained, the mixture can gen; erally be separated into various de?nite fractions by various methods such as steam distillation, 40 fractional distillation, extraction and fractional ' 2. The process for obtaining a mixture of tet ra?uoroethyl carbonylic compounds which com prises heating tetra?uoroethylene with a satu rated aliphatic ketone containing only carbon, hydrogen and oxygen, the mole ratio of said ke tone to said tetra?uoroethylene being from .1 to 10, said heating being effected under pressure in the presence of a peroxygen catalyst at a temper- ' ature within the range of from 75° C. to 250° C. 3. ‘The process for obtaining a mixture of tet crystallization. Products with a given ratio of ra?uoroethyl carbonylic compounds, which com, poly?uoroethylene units per molecule of car »prises heating tetra?uoroethylene with a satu bonyl compound can often be prepared by the rated cycloaliphatic ketone containing only car proper choice of conditions and catalyst. In 45 bon, hydrogen and oxygen, the mole ratio of said crease in pressure favors an increase in molecular ketone to said tetrafluoroethylene being from .1 weight and thus a higher ratio of ?uoroethylene to 10, said heating being effected under‘ pressure units per molecule of product. in the presence of a peroxygen catalyst at a tem- The products can readily be distinguished from perature within the range of from 75° C. to 250° C. the reactants by analysis and by their physical 50 4. The process for obtaining a mixture of tet— properties. In general, the specific gravity and ra?uoroethylcarbonylic compounds, which com stability of the products increase while the re prises heating tetra?uoroethylene with cyclohex fractive index decreases with increase in per anone, the mole ratio of said cyclohexanone to I centage of ?uorine in the products. The products said tetra?uoroethylene being from .1 to 10, said of this invention vary from liquids to relatively 55 heating being effected under pressure in the pres low molecular weight solids which usually soften _ ence of lauroyl peroxide at a temperature within or melt below 300° C. when heated in air on a cop the range of from 75° C. to 250° C. per block. The liquid products are generally 5. A mixture of saturated organic tetrafluorow compatible with the common organic solvents but. ethyl compounds having the'following general the solid products have a rather limited solubility 60 formula: ’ in most solvents.v The reaction and the separation or isolation of wherein ZH is a saturated organic compound of the products may be carried out simultaneously at least two carbon atoms containing only car or in separate steps. The products may be sepa bon, hydrogen and oxygen selected from the class rated by ?ltration, extraction, distillation or crys consisting of aliphatic and cycloaliphatic acids, tallization depending upon the nature of the products. esters and ketones, and n is an integer between 1 and 25. . , The products of this invention are useful for 6. A mixture of saturated organic tetra?uoro various commercial purposes. Since all of the ethyl compounds having the following general products of this invention are extremely stable, 70 formula: they are generally applicable for use as solvents and reaction media. Many of the products have been found to be very desirable in that they are wherein ZH is a. saturated aliphatic ketone con substantially non-?ammable, non-corrosive and taining only carbon, hydrogen and oxygen, and n non-toxic. The saturated organic ?uoro car 75 is an integer between 1 and 25. v 2,411,158 11 '7. A mixture of saturated organic tetra?uoro- v 12 8. A mixture of saturated organic tetra?uoro ethyl compounds having the following general ethyl compounds having the following general formula: formula: H(CFaCFz)nZ H(CF2CF2)1:Z wherein ZH is a saturated cycloaliphatic ketone 5 wherein ZH is cyclohexanone and n is an integer containing‘v only carbon, hydrogen and oxygen, between 1 and 25. and n is an integer between 1 and 25. - WILLIAM EDWARD HANF‘ORD.