US3449389A - Primary fluorocarbon alkoxides - Google Patents

Primary fluorocarbon alkoxides Download PDF

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US3449389A
US3449389A US439973A US3449389DA US3449389A US 3449389 A US3449389 A US 3449389A US 439973 A US439973 A US 439973A US 3449389D A US3449389D A US 3449389DA US 3449389 A US3449389 A US 3449389A
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fluoride
fluorocarbon
alkoxides
cesium
fluorides
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Joseph Leo Warnell
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EIDP Inc
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EI Du Pont de Nemours and Co
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J31/00—Catalysts comprising hydrides, coordination complexes or organic compounds
    • B01J31/02—Catalysts comprising hydrides, coordination complexes or organic compounds containing organic compounds or metal hydrides
    • B01J31/0234—Nitrogen-, phosphorus-, arsenic- or antimony-containing compounds
    • B01J31/0235—Nitrogen containing compounds
    • B01J31/0239—Quaternary ammonium compounds
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J31/00—Catalysts comprising hydrides, coordination complexes or organic compounds
    • B01J31/02—Catalysts comprising hydrides, coordination complexes or organic compounds containing organic compounds or metal hydrides
    • B01J31/0201—Oxygen-containing compounds
    • B01J31/0211—Oxygen-containing compounds with a metal-oxygen link
    • B01J31/0212—Alkoxylates
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C29/00—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring
    • C07C29/68—Preparation of metal alcoholates
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C31/00—Saturated compounds having hydroxy or O-metal groups bound to acyclic carbon atoms
    • C07C31/34—Halogenated alcohols
    • C07C31/40—Halogenated alcohols perhalogenated
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C31/00—Saturated compounds having hydroxy or O-metal groups bound to acyclic carbon atoms
    • C07C31/34—Halogenated alcohols
    • C07C31/42—Polyhydroxylic acyclic alcohols
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C41/00—Preparation of ethers; Preparation of compounds having groups, groups or groups
    • C07C41/01—Preparation of ethers
    • C07C41/18—Preparation of ethers by reactions not forming ether-oxygen bonds
    • C07C41/26—Preparation of ethers by reactions not forming ether-oxygen bonds by introduction of hydroxy or O-metal groups
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G65/00—Macromolecular compounds obtained by reactions forming an ether link in the main chain of the macromolecule
    • C08G65/02—Macromolecular compounds obtained by reactions forming an ether link in the main chain of the macromolecule from cyclic ethers by opening of the heterocyclic ring
    • C08G65/04—Macromolecular compounds obtained by reactions forming an ether link in the main chain of the macromolecule from cyclic ethers by opening of the heterocyclic ring from cyclic ethers only
    • C08G65/22—Cyclic ethers having at least one atom other than carbon and hydrogen outside the ring
    • C08G65/223—Cyclic ethers having at least one atom other than carbon and hydrogen outside the ring containing halogens
    • C08G65/226—Cyclic ethers having at least one atom other than carbon and hydrogen outside the ring containing halogens containing fluorine
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J2231/00—Catalytic reactions performed with catalysts classified in B01J31/00
    • B01J2231/40—Substitution reactions at carbon centres, e.g. C-C or C-X, i.e. carbon-hetero atom, cross-coupling, C-H activation or ring-opening reactions
    • B01J2231/48—Ring-opening reactions
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J2540/00—Compositional aspects of coordination complexes or ligands in catalyst systems
    • B01J2540/20—Non-coordinating groups comprising halogens
    • B01J2540/22—Non-coordinating groups comprising halogens comprising fluorine, e.g. trifluoroacetate
    • B01J2540/225—Non-coordinating groups comprising halogens comprising fluorine, e.g. trifluoroacetate comprising perfluoroalkyl groups or moieties

Definitions

  • This invention relates to new and useful fluorocarbon compounds, and to a method of making the same. These new compounds can be described as fluorocarbon alkoxides.
  • a method for the preparation of salts of primary fluorocarbon alcohols i.e., alkoxides, has now been discovered.
  • the method is to react a fluorocarbon acid fluoride with certain metal fluorides or a quaternary ammonium fluoride at a temperature between -80 C. and 150 C., and preferably between 0 C. and 100 C. and obtaining as a result thereof the primary fluorocarbon alkoxide of the metal.
  • the classical route to alkoxides which route is not possible in fluorocarbon chemistry because of the unavailability of primary fluorocarbon alcohols, is avoided.
  • the reaction can be conducted in a liquid free system, i.e., the reaction between a gas and a solid, or in the presence of an inert organic liquid which is a solvent for at least a portion of one of the reactants.
  • a liquid free system i.e., the reaction between a gas and a solid
  • an inert organic liquid which is a solvent for at least a portion of one of the reactants.
  • which system that is used will depend generally on the state of the reactants underthe reaction conditions, temperature and pressure, employed.
  • the pressure in the reaction system is not critical and can be either subatmospheric or superatmospheric.
  • Suitable solvents are the aprotic polar solvents such as aliphatic ethers and polyethers or aliphatic nitriles.
  • the metal fluorides which can be used in the process of this invention can be defined as (l) MF wherein M is one of the following cations: Cs+, Rb+,
  • M can also be the quaternary ammonium 3,449,389 Patented June 10, 1969
  • the quaternary ammonium fluorides are normally difficult to prepare but can be made from other quaternary ammonium halides by double decomposition with silver fluoride.
  • An alternate route for preparing the ammonium fluoride is to react a fluorocarbon epoxide with quaternary ammonium chloride or cyanide.
  • quaternary ammonium fluorides are the fluorides of tetramethyl ammonium, which is generally considered stable, benzyl trimethyl ammonium, tetraethyl ammonium, tetrabutyl ammonium, and trimethyl octyl ammonium.
  • Ionic fluorides have been used in small amounts to catalyze reactions involving fluorocarbon acid fluorides, but reaction of the ionic fluorides with the acid fluorides or the formation of alkoxides resulting from such reaction has not been detected.
  • An example of the catalytic use of ionic fluorides is to catalyze the reaction between fluorinated acid fluorides and fluorocarbon epoxides, such as hexafluoropropylene epoxide as disclosed in US. Pat. No. 3,114,778.
  • Another example isomerization of and polymerization of fluorocarbon epoxides to acid fluorides.
  • the fluorocarbon acid fluoride reactant in the process of the present invention consists of at least one acid fluoride group, --COF, as the ionic fluoride reactive portion and an unreactive, saturated fluorocarbon radical, including a direct bond between --COF groups in the case of oxalyl fluoride.
  • the fluorocarbon radical has the carbon atom which is a to the acid fluoride group substituted with at least one fluorine atom and preferably with two fluorine atoms. In the latter case and 'When at least two carbon atoms are present in the fluorocarbon radical, it can also be mono-omega-hydrogen substituted.
  • Representative acid fluorides include the alkanoic acid fluorides of the formula R COF wherein R, is the unreactive saturated fluorocarbon radical just described and having a functionality of 1.
  • the alkanoic acid fluorides having this formula include perfluoroacetyl fluoride, perfluoropropionyl fluoride, perfluorobutyryl fluoride, and perfluorodecanoyl fluoride; for each of these acid fluorides, R is the residue, i.e., the compound with the COP group removed.
  • R can also be P, in which case the acid fluoride is carbonyl fluoride.
  • carbonyl fluoride Will be considered an alkanoic acid fluoride.
  • alkandioic acid fluorides include the alkandioic acid fluorides of the formula wherein R, is the unreactive fluorocarbon radical described first above and is difunctional and has no omega carbon atom for mono-hydrogen substitution.
  • the alkandioic acid fluorides include oxalyl fluoride, perfluoromalonyl fluoride, perfluoroadipyl fluoride, and perfluromalonyl fluoride, with R, being the residue of each of these acid fluorides.
  • the preferred alkanoic and alkandioic acid fluorides are the lower alkanoic and alkandioic acid fluorides.
  • fluorocarbon acid fluorides which can be used in the process of this invention are the fluorocarbon epoxides and polymers thereof. While the epoxides are not, strictly speaking, acid fluorides, they do act as such by rearranging to provide a reactive -COF group, viz R" CF COF, in the reaction system with ionic fluorides to obtain an alkoxide.
  • the epoxides may be characterized by the formula wherein the epoxide is terminal as shown and wherein R": is fluorine or an alkyl radical containing from 1 to 8 carbon atoms.
  • Representative epoxides include the perfluorinated epoxides such as hexafluoropropylene epoxide, tetrafluoroethylene epoxide, and perfluorobutylene-l epoxide, and omega-hydrofluorocarbon epoxides such as omega hydroperfluorooctylene-l epoxide.
  • Polymers of fluorocarbon epoxides are prepared by polymerizing the monomer in an aprotic polar solvent at 50 to +50 C. and in the presence of cesium fluoride as a catalyst according to the formula R"; has the same meaning as before and n is a cardinal number of from 0 to about 10.
  • the carbon atom which is a to the carbonyl group will be substituted with an R"; alkyl radical instead of fluorine.
  • the epoxide derived diacid fluoride polymers are prepared by reacting a diacid fluoride hereinbefore described with a fluorocarbon epoxide in an inert organic solvent at -80 to +50 C. in the presence of a tetraethyl ammonium fluoride.
  • novel primary fluorocarbon alkoxides of the present invention which are prepared by reacting the fluorocarbon alkanoic acid fluorides or epoxides or mono-acid fluoride polymers derived from said epoxides, with the ionic fluorides can be represented by the formula wherein x and M have the same meanings as before and R, is a monofunctional fluorocarbon radical which is derived from the reactants recited and is, for example, fluorine or perfluoroalkyl, such as trifluoromethyl and pentafluoroethyl, with lower alkyl (C -C being preferred; omega-hydroperfluoroalkyl, such as omega-hydroperfluoroheptyl, omega-hydroperfluorooctyl, and omegahydroperfluoroethyl, with lower alkyl being preferred and with at least two carbon atoms being present in the radical; and perfluoroalkoxyalkyl, such as per
  • novel primary fluorocarbon alkoxides which are prepared by reacting the fluorocarbon alkandioic acid fluorides or the diacid fluoride derived epoxide polymers with ionic fluorides are either depending on the relative concentration of the reactants and reaction conditions. For example, when an excess of diacid fluoride is used at a temperature less than about C., the monoalkoxide (Formula 7) is formed. Upon heating of the monoalkoxide to moderate temperatures, generally about 5070 C., in vacuum, the dialkoxide is formed by the loss of diacid fluoride. This reaction is reversible, so that by treatment of the dialkoxide with diacid fluoride at a low temperature, i.e, below 30 C., the monoalkoxide is formed.
  • a low temperature i.e, below 30 C.
  • M and x have the same meaning as before and R is a difunctional fluorocarbon radical which is derived from the recited reactants and is, for example, a direct bond in the case of when oxalyl fluoride is the acid fluoride reactant; perfluoropolymethylene such as perfluorodimethylene, perfluorotrimethylene, perfluorotetramethylene, and perfluorooctamethylene, with lower alkene being preferred; or perfiuoroetheralkylene, such as perfluorooxydimethylene.
  • the primary fluorocarbon alkoxides of the present invention are useful as catalysts for the polymerization of fluorocarbon epoxides, and as chemical intermediates for the production of fluorinated chemical compounds and ethers as will be illustrated in the examples which follow.
  • the alkoxides of the present invention Insomuch as a principal utility of the alkoxides of the present invention is to prepare other compounds, the alkoxides generally need not be isolated from the reaction solution if solvent is employed. All parts and percents are by weight unless otherwise indicated.
  • EXAMPLE I 50 gm. of anhydrous cesium fluoride was weighed into a dry flask and stirred under 0.02 mm. Hg pressure at about 200 C. for 18 hours. The flask was then cooled, flushed with dry nitrogen, and 200 ml. of diethylene glycol dimethyl ether, which had been dried by distillation over lithium aluminum hydride was added. The slurry of cesium fluoride in the solvent was then cooled to C. in a solid carbon dioxide bath, with constant stirring, and 23 gm. of carbonyl fluoride was slowly added. The mixture was held at 80 C. for half an hour, then at 30 C. for 3 hours, then warmed to room temperature. A small amount of excess carbonyl fluoride was vented off leaving a solution containing cesium perfluoromethoxide.
  • the cesium perfluoropropoxide was added to a 1 00 cc. flask together with 30 cc. of (CH SO and stirred at room temperature for 18 hrs. in order to methylate the alkoxide.
  • the product was recovered by vacuum distillation. At 25 C. under a pressure drop of 760 mm. to 1 mm. there was recovered 8.0 g. of product; and upon warming from 25 to 40 at 1 mm. pressure, there was recovered an additional 1.5 g. of product.
  • Table I.Vapor pressure of cesium perfluoropropoxide Vapor pressure of A small portion of cesium perfluoropropoxide hydrolyzed in water to give perfluoropropionic acid, cesium fluoride, and hydrogen fluoride.
  • EXAMPLE III Into a dry, stainless steel cylinder containing 20 gms. (0.13 mole) of anhydrous CsF was added 34 gm. (0.2 mole) of perfluoropropionyl fluoride. The cylinder was heated at 110 C. for 72 hrs. and 70 C. for 48 hrs. then cooled to room temperature and degassed. The take-up of perfluoropropionyl fluoride was 120.3 g. (0.123 mole) which corresponded to 95% conversion of CsF to cesium perfluoropropoxide.
  • the F Nuclear Magnetic Resonance spectrum was practically identical to the NMR spectrum of the alkoxide obtained in Example II measured in diethylene glycol dimethyl ether and showed no detectable band due to COF at 25 C.
  • the trifluoromethyl group was measured at a shift of 80.0 p.p.m. and the difluoromethylene groups at 123.4 p.p.m.
  • Methyl perfluoropropyl ether was prepared from cesium perfluoropropoxide by the following procedure:
  • the NMR spectrum of the bisalkoxide showed no carbony] fluoride band, 'but showed an NMR peak at 24.4 p.p.m. shift from CCl F due to -CF O and peaks at 130.2 p.p.m. and 121.2 p.p.m. shift due to the central CF group and the two CF groups adjacent to the central group respectively.
  • the bisalkoxide was converted to the monoalkoxide by placing the salt, at 25 C. under 100 mm. pressure of perfluoroglutaryl fluoride. Slow absorption of the gas to the extent of /2 molar equivalent occurred.
  • EXAMPLE VI 16.7 gms. of stainless steel balls were placed in a 200 ml. stainless steel cylinder together with 25.2 gms. of rubidium fluoride and 51.6 gms. of perfluoropropionyl fluoride. The cylinder was placed on rollers under an infrared lamp (equilibrium temperature about 70 C.) for four days. The volatiles were then vented, a further quantity of 27.5 gms. of perfiuoropropionyl fluoride was added and the treatment was continued for a further four days. The cylinder was then vented. There was recovered 62.6 gms. of a white powder. The weight increase corresponded to a 92.6% conversion of RbF to rubidium perfluoropropoxide.

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Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2107865A1 (enrdf_load_html_response) * 1970-09-22 1972-05-12 Du Pont
US4169960A (en) * 1977-12-01 1979-10-02 Phillips Petroleum Company Removing water from fluorinated alcohols employing a tetrahydrocarbylammonium hydroxide
FR2421861A1 (fr) * 1978-04-06 1979-11-02 Poudres & Explosifs Ste Nale Procede de preparation d'ethers fluores
WO2014110329A1 (en) * 2013-01-11 2014-07-17 E. I. Du Pont De Nemours And Company Quarternary ammonium perfluoroalkoxy salts for preparation of perfluoropolyethers
WO2020137357A1 (ja) * 2018-12-26 2020-07-02 ダイキン工業株式会社 フルオロアルコキシドの製造方法

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114478189A (zh) * 2021-12-31 2022-05-13 西安近代化学研究所 一种全氟烷氧基金属盐及其制备方法和应用

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3250808A (en) * 1963-10-31 1966-05-10 Du Pont Fluorocarbon ethers derived from hexafluoropropylene epoxide

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3250808A (en) * 1963-10-31 1966-05-10 Du Pont Fluorocarbon ethers derived from hexafluoropropylene epoxide

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2107865A1 (enrdf_load_html_response) * 1970-09-22 1972-05-12 Du Pont
US4169960A (en) * 1977-12-01 1979-10-02 Phillips Petroleum Company Removing water from fluorinated alcohols employing a tetrahydrocarbylammonium hydroxide
FR2421861A1 (fr) * 1978-04-06 1979-11-02 Poudres & Explosifs Ste Nale Procede de preparation d'ethers fluores
WO2014110329A1 (en) * 2013-01-11 2014-07-17 E. I. Du Pont De Nemours And Company Quarternary ammonium perfluoroalkoxy salts for preparation of perfluoropolyethers
CN104918907A (zh) * 2013-01-11 2015-09-16 纳幕尔杜邦公司 用于制备全氟聚醚的全氟烷氧基季铵盐
JP2016509597A (ja) * 2013-01-11 2016-03-31 イー・アイ・デュポン・ドウ・ヌムール・アンド・カンパニーＥ．Ｉ．Ｄｕ Ｐｏｎｔ Ｄｅ Ｎｅｍｏｕｒｓ Ａｎｄ Ｃｏｍｐａｎｙ ペルフルオロポリエーテルの調製における第四級アンモニウムペルフルオロアルコキシ塩
US9725456B2 (en) 2013-01-11 2017-08-08 The Chemours Company Fc, Llc Quarternary ammonium perfluoroalkoxy salts for preparation of perfluoropolyethers
WO2020137357A1 (ja) * 2018-12-26 2020-07-02 ダイキン工業株式会社 フルオロアルコキシドの製造方法
JP2020105163A (ja) * 2018-12-26 2020-07-09 ダイキン工業株式会社 フルオロアルコキシドの製造方法
CN113260602A (zh) * 2018-12-26 2021-08-13 大金工业株式会社 氟代醇盐的制造方法
US12338213B2 (en) 2018-12-26 2025-06-24 Daikin Industries, Ltd. Method for producing fluoroalkoxide

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