DE2253534A1 - PERFLUORISOPROPYL NORMAL HEXYL ETHER AND THE USE OF IT - Google Patents

Description

Priority: November 5th, 1971 in USA Serial No .; 196 224

It is known to use organic compounds as inert solvents or diluents for chemical reactions in to use the liquid phase, for example for the reaction of compounds with gases, such as molecular oxygen, Air, molecular nitrogen and carbon dioxide, and gases that are mixtures thereof. Relatively few organic ones However, liquids that are chemically inert will dissolve substantial quantities of such gases. Perfluorinated organic compounds are relatively inert, yet relatively few such fluorinated organic compounds, large amounts of all Dissolve of the above gases are liquid at ambient conditions such as about 20 to 30 ° C.

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Because perfluorinated organic compounds are generally biologically inert and available with viscosities close to that of water, saturated solutions of the above gases in perfluorinated organic liquids have been suggested as gas transport media in liquid ventilation studies of warm-blooded mammals. With liquid ventilation, the lungs, bronchi and trachea of the animal are flooded, ie ventilated, with a saturated solution of an oxygen-containing gas, such as molecular oxygen, air or air enriched with molecular oxygen. The animal inhales the oxygen-containing gas dissolved in the liquid gas transport medium and exhales carbon dioxide as a saturated solution in the gas transport medium, thereby sustaining its life / see LCClark et al, Science, 152, page 1755 (1966) J. Such respiratory system ventilation of warm-blooded Mammals were used not only in studying the respiratory effects of gases containing oxygen other than air, such as mixtures of oxygen and nitrogen with a greater or lesser concentration of oxygen than in air, but also in washing out undesirable substances from the respiratory organs of mammals, such as washing out of mucus secretions from the lungs, bronchi and trachea of animals suffering from asthma and emphysema (see Symposium "Inert Organic Liquids for Biological Oxygen Transport", Fed.Proc. Fed.Amer. Soc.Exp.Biol. 29 (5)) , Page 1698 and following (1970), especially F. GoIlan et al., Loc. Cit. Page 1725 (1970) and d JHModell et el., loc. cit., page 1731).

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Another feature that is required for organic liquids which are used as a means of gas transport in the ventilation of the respiratory system of mammals, is a satisfactory vapor pressure, i.e. a vapor pressure that is equal to the body temperature of warm-blooded mammals (approx

37 ° C) is not excessively high. Some highly fluorinated organic Liquids previously used or suggested for liquid ventilation or flushing of the respiratory system were, such as perfluoro-2-buty! tetrahydrofuran, have undesirably high vapor pressures at around 37 C, such as vapor pressures significantly above around 50 mm Mercury at around 37 ° C. as by J.H. Modell et al., loc. cit., Page 1735, shown, rapid evaporation of such highly volatile liquids from mammalian lungs stretches the alveolar pouches irreparably or tears them and thus leads to pulmonary bleeding or pulmonary blood.tufcz.

It is an object of the present invention to provide a new highly fluorinated to get organic compound that contains large amounts of air, molecular oxygen, molecular nitrogen, Carbon dioxide and gases which are mixtures of the above gases. ,

Another object of the invention is to provide saturated solutions of the above gases in said new highly fluorinated organic To obtain compound that acts as a gas transport medium in liquid ventilation and in flushing the respiratory system from warm-blooded mammals and as inert solvents

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or diluents in chemical reactions in the liquid phase, which cause the reaction of compounds with the Include the above gases can be used.

These and other objects and advantages will become apparent from the following description of the invention.

The above objects and advantages are achieved and at the same time the disadvantages of known highly fluorinated compounds described above of organic compounds overcome when, according to the present invention, the new compound Perfluorisoyccpany-n-hexylather of formula (I) is used.

<r ^F 3

FCO (CH ₂ I ₅ CF ₃ (I)

CF ₃

The present new perfluorinated acyclic aliphatic Ether is chemically and biologically inert and in the liquid phase dissolves large amounts of gas from the group of air, molecular oxygen, molecular nitrogen, carbon dioxide, and gases that are mixtures of these gases. Also closes the inventive idea saturated solutions of these gases in the above new perfluorinated ether, the saturated Solutions are in equilibrium with a vapor phase which contains the gas which is dissolved in the ether. It was particularly surprising to find that the present new ether is not only an exceptionally good solvent for is all of the above gases but also has a range of vapor pressures

be - 5 -

changed according to Eino ^ be

tlnflcgangen on .. &'£ ·.?. $ .. 309819/1 177

of about 40 to 50 mm of mercury at about 37 ° C. Accordingly, the present novel ether can be used as a gas vehicle in ventilating the respiratory system of warm-blooded mammals without any appreciable lung damage can be used, as can be seen from the fact that in the experiment of Example 6 below, practically none Pulmonary bleeding occurs. In contrast is from the above article by Modell et al., op. cit., page 1735, and the last paragraph of Example 6 below, that known perfluorinated ethers, such as perfluoro-2-buty! tetrahydrofuran and Perfluorisopropyläthyläther, with vapor pressures much greater than that of the present new ether, such as shown in the table below, the 'lung tissue is irreparably stretched and destroyed and in this way pulmonary hemorrhage and bring about death yourself.

Tabel

Perfluorinated ether vapor pressure in the body temperature oxygenated atiner of _warm -blooded mammals

(about 37 ° C), (mm Hg)

Perfluoroisop-n-

hexyl ether (I) about 45.6

Perfluoro-2-buty! Tetrahydro- about 72 (calculated from the steam furan, (made by 3M's printing equation for FC-75 in the Co. as FX-80 and FC-75) technical bulletin of 3 M Co.

entitled "Physical Properties Of FC-75" dated January 3, 1962).

Perfluoroisopropylethyl-> 760 (this compound is in ether,

described by JHSimmons Fluid in U.S. Patent
2,500 388

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Provides the new perfluorinated ether according to the invention conveniently by reacting perfluoroisopropyl-6-iododecafluorohexyl ether (II)

FCO (CF ₂ ) ₅ CF ₂ -I (II) CF ₃

with a fluorinating agent such as antimony pentafluoride about 20 to 270 C to replace the terminal iodine substituent with fluorine. The iodine starting material mentioned is a known compound described in Example I (c) of U.S. Patent 3,514,487, which is also more specifically describes the above-mentioned fluorination process.

The new saturated gas solutions that are within the scope of the invention are easily obtained by known methods, such as by bubbling the gas through them through the liquid ether, while the gaseous ether is in equilibrium with a vapor phase, which is the Contains gas, lets come. Although the invention saturated solutions of the above-mentioned gases in the present ether Considered over the entire liquid range of the latter new compound, these solutions are used for liquid ventilation, for flushing the respiratory system, especially solutions according to the invention that are at temperatures between around room temperature, i.e. around 25 C, and around the mean body temperature of warm-blooded mammals, i.e. around 37 ° C, are saturated. The present saturated gas solutions are in equilibrium with a vapor phase, which the

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Contains gas which can be at any partial pressure, but is particularly at a partial pressure in the pressure range which essentially obeys Henry's Law, such as relatively low ones Pressures, such as 0.0001 atm or less, down to about 4 atm. In general, in the present application for Liquid ventilation and purging purposes with the new ether according to the invention uses a saturated gas solution which is in equilibrium with unit gas and the vapor phase containing ether at about atmospheric pressure, i.e. the The vapor phase is at a total pressure of about 1 atm. Typical examples of saturated gas solutions in the new liquid ether (I) that is within the scope of the invention are about the following saturated solutions:

O ₂ dissolved in the liquid (I) at -105 ⁰ C in equilibrium with a compound (I) and containing atm at a total pressure of about 1 that are available vapor phase.

N ₂ dissolved in compound (I) at -100 ⁰ C in equilibrium with a vapor phase containing N ₂ and the compound (I) at a nitrogen partial pressure of 4 contains atm.

A mixture of O ₂ and N ₂ dissolved in the compound (I) at 23 ° C in equilibrium with a vapor phase containing the compound (I) and a mixture of about 99 percent by volume O ₀ and about 1 percent by volume N, wherein the vapor phase is at a total pressure of about 1 atm.

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A mixture of O ₂ and N ₂ »dissolved in the compound (I) at 41 ° C. in equilibrium with a vapor phase which contains the compound (I) and a mixture of 50 percent by volume of 0 and 50 percent by volume of N ₂ , the vapor phase is at a total pressure of about 1 atm.

Air, i.e. components of air dissolved in the compound (I) at 39 ° C, in equilibrium with a vapor phase of Compound (I) and of air with a partial pressure of about 1 atm of air.

O ₂ , CO ₂ and N ₂ dissolved in the compound (I) at 25 ° C in equilibrium with a vapor phase containing the compound (I) and a mixture of about 40 percent by volume of O ₂ , about 0.02 percent by volume of CO ₂ and contains about 60 percent by volume N ₂ , the vapor phase being at a total pressure of about 1 atm.

CO ₂ dissolved in compound (I) at -42 ° C in a balanced weight with a vapor phase (I) and CO ₂ at a total pressure of about 1 atm.

Air, ie the components of air, enriched with CO ₂ , dissolved in the compound (I) at 37 ° C in equilibrium with a vapor phase consisting of the compound (I) and up to 90 percent by volume of C0 ₂ ~ concentration of enriched air , the vapor phase having a total pressure of about 1 atm.

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O ₂ dissolved in the compound (I) at 20 ° C. in equilibrium with a vapor phase of the compound (I) and of O- with an oxygen partial _{pressure of O 1} 000l atm.

Air, ie the components of air, enriched with O ₂ and dissolved in the compound (I) at 37 ° C in equilibrium with a vapor phase, which consists of the compound (I) and with O ₂ up to a volume concentration of 90% O ₂ enriched air, with the vapor phase having a total pressure of about 1 atm.

A Geraisch of N ₂ and O ₂ , dissolved in the compound (I) at 10O ⁰ C in equilibrium with a vapor phase, which the compound (I) and a mixture of 99 volume percent N, ^{un (} ^ ^ volume percent O ₂ contains, where the mixture is present at a CO ₂ * partial pressure of 3 atm, dissolved in the compound (I) at -75 ° C in equilibrium with a vapor phase which contains the compound (I) and CO ₂ qtit a total pressure of 1 atm.

O ₂ dissolved in the compound (I) at 120 ^° C. in equilibrium with a vapor phase which contains the compound (I) and O ₂ at a total pressure of 4 atm.

Mixtures of the above saturated gas solutions in equilibrium with the appropriate vapor phase at a certain temperature are also within the scope of the invention.

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The present new ether and the present saturated gas solutions in this ether can be used for liquid ventilation and the flushing of the respiratory system in warm-blooded mammals such as cats, rats, mice, dogs, hamsters, rabbits and the like, without adverse effects such as destruction of the lung tissue with pulmonary hemorrhage. The ether present is used as a gas transport medium in the above-mentioned aeration according to known methods, as described, for example, in the above-mentioned symposium, the essential technical teaching of which is referred to here. The present ether is particularly suitable for use in irrigation of the respiratory system to remove foreign bodies or undesirable substances, such as mucus secretions resulting from asthma, emphysema or similar diseases. In general, made use of in such an application ethers amount varies depending on the size of the Affected mammal ^u treated, particularly after the volume capacity of the lungs and trachea of the relevant mammals. "

The present new Kther and the saturated solutions, which contain oxygen-containing gases in this ether also useful in the protective ventilation of exhausted mammalian lungs according to the method of E. Lowenstein et al., Fed.Proc.Fed.Aroer. Soc.Exp.Biol. 29 (5), p. 1775 (1970).

The present ether (I), which is chemically and biologically highly inert, is also valuable as a gas-dissolving reaction

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solvent or diluent for reactions in the liquid phase between compounds and air, molecular Oxygen, molecular nitrogen, carbon dioxide and mixtures thereof. In this regard are saturated Oxygen-containing gas solutions according to the invention can be used as solvents or diluents in liquid phase oxidation organic compounds with oxygen-containing Gases such as air, molecular oxygen, or mixtures of molecular oxygen and molecular nitrogen. Saturated Solutions according to the invention, which contain dissolved molecular nitrogen, are in liquid phase reactions of molecular nitrogen with organometallic phosphorus compounds of M.E. Vol'pin et al., Izv.Akad.Nauck. SSSR Ser. Khim. 1966 (6), p. 1083; Chem. Abstracts 65, column 1374 h, 1966, and in exchange reactions of molecular nitrogen in the liquid phase of the A.K.Shilova et al., Kinat.Katal 10 (2), p. 267 (1966), Chem. Abstracts 71, column 25095 ρ (1969) useful. Solutions of the present ether saturated with carbon dioxide are particularly useful as reaction solvents in the known carboxylation of organomagnesium halide compounds, like Grignard compounds, especially for the carboxylation of a polyfluoroisoalkoxyalkylmagnesium iodide, as described, for example, in Example 6 of U.S. Patent 3,453,333. As will be apparent to those skilled in the art , reactions of the above type can be carried out using the present ether as a gas-dissolving solvent or diluent at a temperature above normal

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Boiling point of the ether, provided that the reaction according to conventional reaction methods takes place at a sufficiently high pressure to keep the ether in the liquid phase at the reaction temperature.

The following examples serve to further illustrate the invention, percentages and quantitative ratios being percentages and weight ratios by weight and the temperatures being given in C, unless expressly stated otherwise. The gas solubilities listed in the following examples are measured with an accuracy of -2 cm.

example 1

During a time of about 30 minutes, 50.0 g (0.082 mol) perfluoroisopropyl 6-iodo-dodecafluorohexyl ether (II) with stirring to 127 grams (0.59 moles) of antimony pentafluoride added, which is kept at 70 to 80 ° C. The resulting mixture is allowed to cool to 25 ° C. and poured then in about 500 jml ice water. The lower organic layer is separated, washed twice with water and over anhydrous Calcium chloride dried. Fractional distillation of the resulting dried crude product at atmospheric pressure provides 28.5 g (yield 69% of theory, based on the iodide starting material) of distilled product, namely Perfluoroisopropyl-n-hexyl ether, boiling point 121 C at atmospheric pressure having the structural formula (I) above.

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The structural formula given is obtained by nuclear magnetic resonance spectral analysis of the product for the groups

> CP-, -CF ₂ , -CF _{3 and -OCF 3} - and confirmed by infrared spectral analysis of the product.

The frozen product of the product, as determined by a conventional freezing method, located at -105 ⁰ C, The heat of vaporization and the vapor pressure equation, which characterize the product are 8130 calories / gram moles and

log ρ = 1.J8911 - 1777.25

where ρ is the vapor pressure in mm of mercury and T is the temperature in Kelvin degrees (determined from the normal Boiling point of the product according to the method of R.C. Reid et al., "The Properties of Gases and Liquids", McGraw Hill Publishing Co., Second Edition, 1966, pages 152-153).

The critical pressure, the critical temperature and the critical volume of the product, determined by Lyderson methods according to RCReid et al., Loc. Cit., Pages 3 to 10, 22, 24 and 28, are 234 ° C., 20.3 atm and 457 cm ³ / g / mol.

The densities of the product in g / cm, measured at various temperatures in the range from 20 to 45 ° C using conventional methods, are as follows: 20 °, 1.732? 25 °, 1.721? 30 °, 1.709; 35 °, 1.696? 40 °, 1.683? 45 °, 1.661.

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Example 2

(a) Following the procedure of J.Rellly and W.N.Rae, Physicochemical Methods, D. Van Nostrand Co., Volume III (Supplement) 1948, pages 145 to 148, is a sample of the ether product of Example 1 degassed, saturated with dissolved molecular oxygen and with respect to dissolved molecular oxygen analyzed after looking at the solution at about 25 C with a vapor phase of molecular oxygen and the ether equilibrated with a total pressure of about 1 atm. The at about 25 C under the above conditions The amount of molecular oxygen dissolved in the ether product of Example 1 is after a correction to standard temperature and ~ pressure conditions and on an oxygen

3 3 partial pressure of 1 atm approx. 47.4 cm per 100 cm of ether.

(b) The procedure of part (a) above is repeated essentially as described to measure the solubility of molecular oxygen in the ether product of Example 1 at 37 ° C with the ether solution saturated with molecular oxygen in equilibrium with a vapor phase of molecular Oxygen and ether have a total pressure of about X atm. The amount of molecular oxygen dissolved in the ether is about 45.6 cm per 100 cm of the ether after correction to standard temperature and pressure conditions and to 1 atm oxygen partial pressure.

The above values show that, according to Henry's Law, the in saturated solutions of molecular oxygen in the

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Aether product of Example 1 at temperatures in the range of

about 25 to about 37 ° C dissolved amount of molecular acid

fabric about 47.4 to about 45.6 cm (corrected for temperature and Pressure standard conditions) per 100 cm of ether per unit of atmospheric pressure of molecular oxygen in the vapor phase is in equilibrium with the solution.

Example 3

The procedure of Example 2 is essentially as described repeated to measure the amount of molecular nitrogen present in saturated solutions of molecular nitrogen is dissolved in the ether product of Example 1 at about 25 ° C and about 37 ° C, the saturated solution in the Equilibrium with a vapor phase of molecular nitrogen and ether at a total pressure of about 1 atm. The measured solubility of molecular nitrogen at around 25 ° C is after correction for temperature and Standard pressure conditions and to 1 atm nitrogen equilibrium pressure

3 3

about 31.1 cm per 100 cm of the ether, and the measured solubility of molecular nitrogen at about 37 ° C is

after a correction to standard temperature and pressure

conditions and to 1 atm nitrogen partial pressure about 31.0 cm 100 cm each of the ether.

The above values show that, according to Henry's Law, the amount of molecular nitrogen dissolved in saturated solutions of molecular nitrogen in the ether product of Example 1 at a temperature in the range of about 25 to about 37 ° C is about 31, 1 to about 31.0 cm ³ (corrected to

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225353A

Temperature and pressure standard conditions) per 100 cm des Ether per unit of atmospheric pressure of molecular nitrogen in the vapor phase in equilibrium with the solutions.

Example 4

The procedure of Example 2 is repeated essentially as described to measure the amount of carbon dioxide those in saturated solutions of carbon dioxide in the ether product of Example 1 at about 25 and at about 37 ° C is dissolved, each saturated solution being in equilibrium with a vapor phase of carbon dioxide and ether at one Total pressure of about 1 atm. The measured carbon dioxide solubility at around 25 ° C is after the correction Standard temperature and pressure conditions and on 1 atm of carbon

3 3 dioxide partial pressure about 137.4 cm per 100 cm of the ether, and the measured carbon dioxide solubility is about 37 C. after correction to standard temperature and pressure conditions and to 1 atm of carbon dioxide partial pressure about 151.1 cm each 100 cm of the ether.

The above values show that according to Henry's Law the amount of carbon dioxide present in saturated solutions of carbon dioxide in the ether product of Example 1 at temperatures is dissolved in the range of about 25 to about 37 ° C, about 173.4 to about 151.1 cm (corrected for temperature and standard pressure conditions) per 100 cm of ether per unit of atmospheric pressure of carbon dioxide in the vapor phase in equilibrium with such solutions.

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Example 5

The procedure of Example 2 is essentially as described repeatedly to measure the amount of air, i.e. the Total amount of the constituents of air in saturated solutions of air in the ether product of Example 1 is about 25 and dissolved at about 37 ° C, with any saturated solution in equilibrium with a vapor phase of air and Ether is under a pressure of about 1 atm. The measured air solubility at around 25 ° C is after correction to standard temperature and pressure conditions and to 1 atm

3 3

Air partial pressure about 34.5 cm per 100 cm of the ether, and the measured air solubility at about 37 ° C is according to the same correction about 34.1 cm per 100 cm of aether.

The above values show that according to de "Henry" see law the amount of air, i.e. the total amount of the constituents of air, dissolved in saturated solutions of air in the ether product of Example 1, at temperatures ranging from about 25 to about 37 ° C, from about 34.5 to about 34.1 cm (corrected for standard temperature and pressure conditions) in 100 cm of the ether per unit of atmospheric pressure of the air in the vapor phase in equilibrium with such solutions,

The following example explains the use of the ether product of Example 1 as a gastric exercise agent for flushing the respiratory system of a warm-blooded mammal.

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Example 6

A normal dog weighing 13.4 kg and with a body temperature of about 37 C is used with sodium pentabarbital anesthetized. The dog's windpipe is opened. A few grams of viscous mucus from the lungs of the dead Dogs with emphysema are inserted into the windpipe so that they are against the lower walls of the windpipe be liable. The mucus implantation simulates the presence of pathological mucus secretions that affect the airways block and impair breathing in emphysema and asthma.

The trachea is then intubated above the saliva transmission. A polyethylene catheter is threaded into the abdominal aorta through the left femoral artery to allow blood samples to be drawn and pressure to be recorded. Arterial blood oxygen vapor pressure (in millimeters of mercury) and arterial blood pH are recorded using direct reading electrodes while the dog is breathing air and then for 20 minutes while the dog is breathing pure oxygen. The dog's breathing is made difficult by the partial blockage of the windpipe. The oxygen vapor pressure of the arterial blood and the pH of the arterial blood are reduced and the carbon dioxide vapor pressure of the arterial blood i, t is somewhat increased, compared with the normal reading, owing to the reduced ventilation.

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The dog is then administered intravenously Succinylcholine hydrochloride paralyzes, and the endotracheal Tube is ventilated with the atmosphere with the lower part of a Connected glass container, which contains about 1000 ml of the ether product according to Example 1. The ether is at about 25 ° C saturated with dissolved molecular oxygen and in equilibrium with an overlying steam atmosphere of ether and oxygen at a total pressure of about 1 atm with the help of a stream of molecular oxygen, which continuously through the ether via a gas distribution tube at a rate of about 3 to 5 liters is pearled every minute. The dog's lungs and windpipe become tidal with parts of volume (each about 400 ml) of the ether is ventilated by lifting and lowering the container 3 to 4 times per minute to the respiratory system alternating between flooding and emptying the dog, whereby the exact speed of raising and lowering is controlled according to the time it takes to reach the consumed Ether, which is substantially saturated with exhaled carbon dioxide, is returned to the container.

During aeration, the transferred mucus is in small clumps from the trachea along with the outflowing mucus Ether is flushed out and remains floating on the surface of the ether in the container. During ventilation the temperature of the gas transport ether remains between about room temperature (about 25 ° C) and the body temperature of the Dog (about 37 ° Ci and the ether in the container is in

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essentially blood free, indicating that the ventilation has practically no pulmonary bleeding or pulmonary tissue destruction takes place.

Continuous aeration of the animal is stopped after about 1 hour and the fluorinated ether is released from the

under

The dog's respiratory system by flowing out of its own Weight drained. The endotracheal tube is then fitted with a gas containment bag and a non-breathing valve and the dog is allowed to breathe 100% molecular oxygen for about 3 hours. Then the dog will extubated and placed in an oxygen tent. After one him molecular oxygen with a volume concentration of oxygen of about 30 to 40% air enriched allowed to inhale for about 24 hours, the dog is returned to a standard observation kennel under observation. After five days, the lung functions return, the oxygen vapor pressure of the arterial blood, the carbon dioxide vapor pressure of the arterial blood and the pH of the dog's arterial blood return to normal conditions, and the Dog seems normal in all respects.

The one flushed out of the dog with the ventilation experiment above Slime is extracted from the ether container and weighed. It became an essentially quantitative recovery of the transferred mucus achieved, which shows the effectiveness of the ether according to Example 1 as a detergent.

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In an attempt to carry out the above experiment using perfluoroisopropyl ethyl ether with a boiling point of 28 ° C at 1 atm as a gas transport medium (this ether was essentially following the procedure of the example 1 using perfluoroisopropyl-2-iodotetrafluoroethyl ether obtained as iodide starting material), the dog's lung tissue is stretched and destroyed and yields heavy bleeding from the lungs, so that the dog dies.

The invention thus also relates to a method for ventilation of the respiratory system, which is characterized in that the the solvent used was a saturated perfluorinated ether with a vapor pressure in the range of 40 to 50 rom mercury at 37 ° C.

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Claims (3)

225 3 5 Claims 1J) Perfluoroisopropyl-n-hexyl ether of the formula FCO- (CF ₂ J ₅ CF ₃ 2.) Use of the perfluoroisopropyl-n-hexyl ether after Claim 1 as a solvent for air, molecular oxygen, molecular nitrogen, carbon dioxide and a mixture of this in equilibrium with a vapor phase containing these gases and the ether. 3.) Means for liquid ventilation or irrigation of the respiratory system, consisting of a solution of air, molecular oxygen, molecular nitrogen, carbon dioxide and / or mixtures here-from a solvent, characterized in that the solvent is perfluoroisopropyl-n-hexyXether contains. 3 0 9 8 19/1177