CA1176657A - Production of carboxylic acids from acylium anions formed by carbonylation - Google Patents
Production of carboxylic acids from acylium anions formed by carbonylationInfo
- Publication number
- CA1176657A CA1176657A CA000404467A CA404467A CA1176657A CA 1176657 A CA1176657 A CA 1176657A CA 000404467 A CA000404467 A CA 000404467A CA 404467 A CA404467 A CA 404467A CA 1176657 A CA1176657 A CA 1176657A
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- Prior art keywords
- fluoride
- recited
- acid
- acyl
- ninety
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C51/00—Preparation of carboxylic acids or their salts, halides or anhydrides
- C07C51/10—Preparation of carboxylic acids or their salts, halides or anhydrides by reaction with carbon monoxide
- C07C51/14—Preparation of carboxylic acids or their salts, halides or anhydrides by reaction with carbon monoxide on a carbon-to-carbon unsaturated bond in organic compounds
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C51/00—Preparation of carboxylic acids or their salts, halides or anhydrides
- C07C51/04—Preparation of carboxylic acids or their salts, halides or anhydrides from carboxylic acid halides
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C51/00—Preparation of carboxylic acids or their salts, halides or anhydrides
- C07C51/10—Preparation of carboxylic acids or their salts, halides or anhydrides by reaction with carbon monoxide
- C07C51/12—Preparation of carboxylic acids or their salts, halides or anhydrides by reaction with carbon monoxide on an oxygen-containing group in organic compounds, e.g. alcohols
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- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Oil, Petroleum & Natural Gas (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
ABSTRACT OF THE DISCLOSURE
A carboxylic acid, e.g., isobutyric acid, is produced by reacting an acyl fluoride, e.g., isobutyryl fluoride, with less than the total amount of water required to hydrolyze all of the acyl fluoride to the carboxylic acid under con-ditions whereby the anhydrous acid, e.g., HF, forms.
A carboxylic acid, e.g., isobutyric acid, is produced by reacting an acyl fluoride, e.g., isobutyryl fluoride, with less than the total amount of water required to hydrolyze all of the acyl fluoride to the carboxylic acid under con-ditions whereby the anhydrous acid, e.g., HF, forms.
Description
65'7 PROD~CTION OF CARBOXYLIC ACIDS FROM ACYL FLUORIDES
PORMED BY CARBONYLATI~N
ACKGROUND O~ T~E IN~ENTI N
A. Field of the I~nventIon The invention relates to formation of carboxylic acids by hydrolysis of acyl fluorides formed from carbon monoxide, anhydrous acid, and organic compound with one or rnore double bonds and/or esters.
B. Description of the Prior Art The prior art such as GB 942,367 stresses the require-ment of aqueous acid catalyst systems for production of carboxy-lic acid by carbonylation of compounds having one or more double bonds, or esters followed by further hydrolysis of the reaction products with excess wa~er to produce carboxylic acids. In these processes, the aqueous acid medium is corrosive and ex-pensive equipment is required. The prior art problems are overcome by the process described hereln for forming carboxylic acids.
SUMMARY OF THE INVENTION
Carboxylic acids, e.g., isoDutyric acid, are formed by hydrolysis with less than the stoichiometric amount of water required to react ~ith all of the acyl fluoride, e.g., isobutyryl fluoride, to form the carboxylic acid and to re-generate the anhydrous acld, e.g., ~ydrogen fluoride. The acyl fluoride is formed by the reaction of carbon monoxide, anhydrous hydro~en fluoride acid, and an organic compound capable of ~eacting with carbon monoxide and the anhydrous acid, e.g., propylene, under conditions whereby an acyl fluoride, e.g., isobutyryl fluoride, forms. In other embodiments of the 3Q invention, part or all of the carboxylic acid, e.g., isobutyric acid, is separated from the hydrolyzed m~xture and the remainder of the hydrolyzed ~xture after part or all of the carboxylic .:,................................................... 11~
~t7665~7 ac2d is separa~ed t~ere~ro~ ~e.g.~ hyd~ogen fluoride, u~-reacted iso~u~yxyl fluoride, unsepa~ated iso~utyric acid) is recycled tQ reac~ with the organic compo~nd ~e.g. propylene2 to form more acyl fiuoxide Ce.g., isobutyryl fluoride~.
DESCR~P~ION ~F THE INVENTION
Th~ novel discove~ed process for producing a carboxylic acid from an acyl fluoride comprises the step of:
hydrolizing a mixture compris~d or an acyl fluoride formed by the reaction of carbon monoxide, anhydrous hydrogen fluoride acid and an organic compound described herein with less than the stoichiometric amount of water required for hydrolyzing all of the acyl fluoride in the mixture to the carboxylic acid. This reaction is carried out under conditions whereby the carboxylic acid forms and t~e acid is regenerated as described herein.
In other embodiments of t~e inyention, the process further comprises the step or steps of:
separating from (1~ to one hundred (100) percent of the anhydrous hydrogen fluoride acid from the hydrolyzed mixture and recycling fr~m one ~l) to one hundred ~100) percent of the separated anhydrous acid for reaction with carbon monoxide and the organic compo~nd descri~ed herein to form more of the mixture comprised of the acyl fluoride and the anhydrous acid.
In another embodiment of the invention, the process ; 25 can comprise the step of:
separating from one (1) to one hundred (100) percent of the carboxylic acid from the hydrolyzed mixture, and recycling from one (l) to one hundred (100) percent of the hydrolysis p~oduct mixture remaining after separation of the car~oxylic acid therefrom, for reaction with carbon monoxlde and ~he organic compound described herein to form more of the mixture comprised of the acyl fluoride product.
~6~i'7 _ 3 -REACTANTS
-The xeactants to for~ the acyl fluoride may be from any source, but must be free from deleterious materials which interfere with the process described hereinO ~he total amount of water in the reaction mixture to be hydrolyzed must be less than the stoichiometric a~ount of water re-quired to react with all of the acyl fluoride formed.
The carbon monoxide may be-from any source, but is preferably substantially free from water so as to maintain substantially anhydrous reaction conditions. The carbon monoxide may be diluted with other substances which do not interfere with the reaction. For example, dry synthesis gas or combustion gas may be used. It is preferred that dry carbon monoxide itself be used.
The organic compounds are those which are capable of reacting with carbon monoxide and the anhydrous hydrogen fluoride acid; that is, carbonylated to form an acyl fluoride, for exa~ple, organic esters described herein or organic compounds having at least one double bond capable of carbonyl-ating to an acyl fluoride described herein.
The organic esters are represented by the general Q
formula R - C - 0 - R', whereln R is an alkyl of up to twenty carbon atoms, such as methyl, ethyl, dodecyl, eicosanyl.
Preferably the alkyl is methyl, ethyl, propyl, or isopropyl, with ethyl and isopropyl being the most preferred. R' is an alkyl of from two to twenty carbon atoms, such as ethyl, propyl, t-~utyl, dodecyl, eicosanyl. Preferably R' is ethyl or isopropyl, with isopropyl being the most preferred.
When an organic ester is used in the process described herein, any one of the esters mentioned herein may be used. lt is preferable, however, to use isopropyl :
6" t~ .
, 1~76657 ~ 4 -iso~uty~ate (2-propanol 2-methylpropionatel, ethyl iso~utyrate (ethanol 2-metAylproprionate), lsopropyl propiona~e (2-propanol propionatel or ethyl propionate Cethanol propionate~, and it is espec'ally preferred to ~se isopropyl isobutyrate or ethyl propionate.
Examples of orsanic compounds having at least one dou~le bond capable of forming an acyl fluoride therewith (car~onylating to an acyl fluoridel which may be used in the process described herein are olefins of up to twenty carbon atoms, such as ethylene, propylene, butenes, 1,3-butadiene, and dodecene. The olefins may be su~stituted with alkyl, or aryl, or cycloalkyls, or other su~stituents which do not interfere in the process described herein. Furthermore, the olefins may have multiple double bonds within the molecule lS which does not interfere in the process described herein such as l,3~butadiene. Preferred olefins are ethylene, propylene, isobutene, l-butene, 2-butene, and 1,3-butadiene, and ethylene and propylene are highly preferred.
Although all of the organic compounds described herein may be used in the process described herein, propylene, however, is especially preferred.
The hydrogen fluoride acid used for the preferred process to make the acyl fluoride described herein should be substantially free from water; that is, anhydrous. The term "anhydrous" as used herein and in the claims refers to hydrogen ~luoride acid which is substantially free from water, e.g., less than 2000 parts per million or if water is present, it does not interfere with the reaction to form the acyl anion.
REACTION CONDITIONS
The reaction of car~on monoxide, with an organic compound described herein and the anhydrous hydrogen fluoride acid described herein, can occur at temperatures of from ~1~6657 zero degree Centigrade (:ODCl to one hundred degrees Cen~igrade tlOOC), the upper temperature being determined by side prod~ct formation, For the reaction between the preferred reactants described herein, the temperature can De from forty degrees Centigrade (4QCl to eighty degrees Centigrade ~80C), but preferably it is at a~out sixty degrees Centigrade (60C).
The carbon monoxide pressure can ~ary from one tl) bar ~14.7 psia) to about 40~ bars ~6,0QO psia), but generally it is from 34 bars (500 psia) to 340 bars (5,000 psia), and prefer-ably from 102 bars (1,500 psia) to 136 bars (2,000 psia~, the pressure ~eing increased as required for the solubility of carbon monoxide in the anhydrous acid and to increase the productivity of the reactor.
The mole ratio of anhydro~s acid to the organic compound described herein should be from 1:1 to 100:1, but generally it is from 10:1 to 20:1 and preferably about 15:1.
The mole ratio of carbon monoxide to the orsanic compound described herein is from 1:1 to 5:1 or ~igher, but prefer-ably it is from 1.5:1 to 1:1 and corresponds to the satura-tion limit of carbon monoxide in the reaction mixture during and at the end of the reaction.
All of the carbon monoxide and anhydrous acid, e.g., anhydrous hydrogen fluoride, which is to be reacted with the organic compound, should be thoroughly mixed prior to contacting with the organic compound described herein, e.g., propylene, then the organic compound is rapidly reacted while mixing with the premixed carbon monoxide and acid. Generally, the reaction, depending upon the pressure and the temperature, will occur within minutes to form an acyl fluoride, e.g., isobutyryl fluoride. The organic compound itself can be diluted with carbon monoxide or inert diluents, e.g., propane, prior to reaction with the anhydrous ~76657 acid.
The reaction ~an be condu~ted in a semi-batch reactor-,- plug flow reactor, back mix reactor (CSTR), or other reactor known to those skilled in the art, ~ut the preferred reactor is a plug flow Eeactor.
The hydrolysis reaction of the acyl fluoride, e.g., isobutyryl fluoride, with water can occur at temperatures from twenty degrees Centigrade ~20C) to one hundred fifty degrees Centigrade (150C) and at pressures from 1 bar (14.7 psia) to 340 bars (5,000 psial, but normally it occurs at temperatllres from forty degrees Centigrade (40Cl to seventy degrees Centigrade (70C~ and pressures at 6.8 bars (lQ0 psia) to 2Q4 bars (3,000 psia). The temperature and pressure being set to avoid the decomposition of the intended products, and to facilitate product separations.
~t is preferred that the reactants be stirred during ; hydrolysis. In many cases, when rapid mixing is used, the hydrolysis reaction with the concurrent regeneration of the anhydrous acid, e.g., HF, can be completed within seconds to minutes The critical feature of the hydrolysis reaction is maintaining the mole ratio of water to the acyl fluoride product below 1:1; that is, the total amount of water reacted with ; the mixture comprised of the acylium anion product must be less than the amount of water required for all of the acyl fluoride to form the carboxylic acid.
` The total amount of water ~ay be injected into the mixtu~e comprised of the acyl, but preferably the water is added in partial amounts into the mixture comprised of the acyl fluoride. The hydrolysis step is exothermic, and thus cooling may be required. The mixture may also contain carbon monoxide, unreacted organic compound, anhydrous hydrogen fluoride acid, and carboxylic acid. Preferably the mixture 7 ~76~S7 contains the anhydrous hydrogen fluoride acId, particularly when the acyl fluoEide is sobutyryl fluorlde. ~hen isobutyryl fluoride is hydrolyzed, the ratio of the amo~nt of anhydrous hydrogen ~luoride to iso~utyryl flu~ride is in the range from 0.01 to 95.5 parts by weight of anhy~ro~s hydrogen fluoride ~AHP) to ~9.Q~ ~o 4.5 parts ~y weight of isobutyryl fluoride (IBF), but prefera~ly from la.~ to ~0.0 parts ~y weight of AHF to 9Q to lQ parts by weight of IBF. The amount of an-hydrous hydrogen fluoride acid in the mixture is dependent upon the efficient operation of the process, and the ease of separating the anhydrous hydrogen fluoride acid from the product mixture comprised of the acyl fluoride, e.g., isobutyryl fluoride, hydrogen fluoride, and carbon monoxide.
After the hydrolysis reaction is complete, which depends upon the reaction conditions as known to those skilled in the art, from one (l) to one hundred (100) percent of the carboxylic acid formed is separated from the product mixture of the hydrolysis reaction. Preferably from eighty (80) to one hundred (lO0) percent of the carboxylic acid is separated, and the remaining hydrolysis product mixture is recycled for further reaction with the reactants to form more acyl fluoride product. This recycle stream may contain carbon monoxide and/or anhydrous acid and/or unreacted organic compound and/
or the unhydrolyzed acyl fluoride.
In another embodiment of the invention, from one (1) to one hundred (lO0) percent (preferably from eighty (80) to one hundred (lO0) percent) of the anhydrous hydrogen fluoride acid is separated from the hydrolysis product mixture and is recycled back for reaction to form more acyl fluoride.
Tne recycle stream may contain small amounts of unseparated unhydrolyzed acyl fluoride and/or carboxylic acid and/or unreac~ed organic compound.
~, ~
~76657 The separatlon can be by any of the known methods of separatlon, such as distillation ~r sol~ent extraction.
EXAMPLES
..
The f~llowing e~amples will ilLustrate t~e invention described ~erein.
The following procedure was ~sed to study the hydrolysis of isobutyryl fluoride based on 90 mole percent of the stoichiometric amount of water required to hydrolyze all of the isobutyryl fluoride to isobutyric acid, under semi-adiabatic conditions.
A two liter Hastelloy C Parr reacto~, equipped withwater delivery system (used nitrogen at 5Q0 psia), a thermo-couple connected to a continuous temperature recorder, and an air motor and stirrer adjusted to rotate at l,000 revolutions per minute, was charged with a weighed amount of anhydrous hydrogen fluoride and isobutyryl fluoride (maintained at dry ice-acetone temperature). After charging, the reactants and reactor are brsught to the preselected temperature, and the temperature recorder is started. The weighed amount of water (90 wt.~ of the stoichiometric amount required for reaction of all of the iso~utyryl fluoridel is then ejected. The initial temperature of the water was at room temperature.
After hydrolysis was complete, the mixture was analyzed by gas chromatography. From the temperature-time recording, the temperature rises were noted. Generally, the first was attri-buted to the heat of mixing, and the second was attri~uted to the hydrolysis reac~ion.
Example I
A mixture of 57.6 grams of anhydrous hydro~en 3Q fluoride (lO wt~ percent) and 464.~ grams of isobutyryl fluoride (~0 wt. percent) at 26.8C was hydrol~zed by injecting 83.0 grams of water (at 21C). The reaction mixture tempera-ture rose to 52.4C, then cooled over a 27-second period to 6~i7 _ 9 _ 44C, and then rose exponentially t~ 123C in 4~ seconds. Two phases were obser~ed at the beginnin~ but not at the end of the hydrolysis. The reaction was complete; the analysis showed only isobutyric acid for~ed.
Example II
A mixture of 25.5 grams of anhydro~s hydrogen fluoride ~5 wt. percent) and 488.9 grams of iso~utyryl fluoride ~`95 wt. percent) at 24.1C was hydxolyzed with 87.1 grams of water at 21C. A temperature rise of 13.5C was observedO After twenty minutes when no further temperature rise was noted, the reactor was then externally heated to 51C, and a second temperature rise wlth a temperature change of 78C was obserYed o~er a 99-second inter~al. ~he reaction was complete, the analysis showed only the formation of isobutyric acid.
Exam=ple III
A mixture of 51.6 grams (lQ wt. percent) anhydrous hydrogen fluoride and 464.5 grams (90 wt. percent) isobutyryl fluoride at 223 Centigrade was hydrolyzed by adding 83.2 grams of the water Cat 21C) over a 25-second period. Under these conditions no temperature rise due to mixing was obser~ed.
Instead, the temperature rose continuously from 22 Centigrade to 104 Centigrade, and it was obser~ed that the hydrolysis reaction was limited by the rate of water addition, thus indicating the preferred method of adding water at the ra~e at which hydrolysis occurs. The reaction was complete, the analysis showed only isobutyric acid formed. The experimental heat of hydrolysis calculated about 9.5 kcal per gram of isobutyric acid formed.
Exam~le IV
The following continuous process can be conducted to produce isobutyric acid by the process described herein.
~l~7~6S7 - 10 ~
A plug flow~reactor is used for the formation of iso~utyr~c acid f~om propene. It ~s f~rmed fro~ a forty (40) foot tube having a one-half (~/2) inc~ internal diameter, with a premix section of about five C5) feet and equipped w~th injection points at five-foot intervals ~nd ~ heater. The carbonylation reaction is conducted at 50C and 2,800 psig (192 bars) with propene, anhydrous hydrogen fluoride and carbon monoxide in a mole ratio of 1.0:14:1.3, at a flow rate of 3.2 lbs. per hour (1.52 kilograms per hour). The an-hydrous hydrogen fluoride and carbon monoxide is injectedinto the premix section where they are thoroughly mixed, and the propene is injected into the mixture of anhydrous hydrogen fluoride and carbon monoxide at five-foot intervals, with the final addition being 30 feet from the beginning of the reactor. After the reaction is complete, at the 35-foot injection point, water is injected into the reactor where the hydrolysis occurs preferably at the rate at which hydrolysis occurs and isobutyric acid is formed. The amount of the water injected is less than the amount of isobutyryl fluoride formed. This section of the reactor where the hydrolysis occurs is maintained at approximately 100C and at a pressure of 2,800 psig. The isobutyric acid and any heavy products, such as heavier oligomeric acids (which are less than 3 wt.
percent), are separated from the final product mix~ure by simple distillation, and the remaining isobutyryl fluoride, carbon monoxide and anhydrous hydrogen fluoride is recycled with the carbon monoxide and anhydrous hydrogen fluoride that are being injected lnto the premix section of the reactor.
In another embodiment of the continuous reaction, prior to hydrolysis, the product mixture containing the acyl fluoride (isobutyryl fluoride)is passed to a separation unit - where the excess caxbon monoxide and from ten to ninety percent ~:~7~65~
of the excess anhydxous hydrogen fluoride is remQye~, and recycled, while the re~aining prQduct ~xture preferably haying 10 parts by weight of anhydr~us hyd~Qgen fl~oride to ~0 paxts by weisht of isobutyryl fluoxide is hydxolyzed as described hexein followed by separation of isobutyric acid and recycling of the remaining product mixture of unreacted isobutyxyl fluoride and anhydrous hydrogen fluoride.
While the invention has been described with refer-ence to specific details of certain illustrative embodiments, it.is not intended that it shall be limited thereby except insofar as such details appear in the accompanying claims~
PORMED BY CARBONYLATI~N
ACKGROUND O~ T~E IN~ENTI N
A. Field of the I~nventIon The invention relates to formation of carboxylic acids by hydrolysis of acyl fluorides formed from carbon monoxide, anhydrous acid, and organic compound with one or rnore double bonds and/or esters.
B. Description of the Prior Art The prior art such as GB 942,367 stresses the require-ment of aqueous acid catalyst systems for production of carboxy-lic acid by carbonylation of compounds having one or more double bonds, or esters followed by further hydrolysis of the reaction products with excess wa~er to produce carboxylic acids. In these processes, the aqueous acid medium is corrosive and ex-pensive equipment is required. The prior art problems are overcome by the process described hereln for forming carboxylic acids.
SUMMARY OF THE INVENTION
Carboxylic acids, e.g., isoDutyric acid, are formed by hydrolysis with less than the stoichiometric amount of water required to react ~ith all of the acyl fluoride, e.g., isobutyryl fluoride, to form the carboxylic acid and to re-generate the anhydrous acld, e.g., ~ydrogen fluoride. The acyl fluoride is formed by the reaction of carbon monoxide, anhydrous hydro~en fluoride acid, and an organic compound capable of ~eacting with carbon monoxide and the anhydrous acid, e.g., propylene, under conditions whereby an acyl fluoride, e.g., isobutyryl fluoride, forms. In other embodiments of the 3Q invention, part or all of the carboxylic acid, e.g., isobutyric acid, is separated from the hydrolyzed m~xture and the remainder of the hydrolyzed ~xture after part or all of the carboxylic .:,................................................... 11~
~t7665~7 ac2d is separa~ed t~ere~ro~ ~e.g.~ hyd~ogen fluoride, u~-reacted iso~u~yxyl fluoride, unsepa~ated iso~utyric acid) is recycled tQ reac~ with the organic compo~nd ~e.g. propylene2 to form more acyl fiuoxide Ce.g., isobutyryl fluoride~.
DESCR~P~ION ~F THE INVENTION
Th~ novel discove~ed process for producing a carboxylic acid from an acyl fluoride comprises the step of:
hydrolizing a mixture compris~d or an acyl fluoride formed by the reaction of carbon monoxide, anhydrous hydrogen fluoride acid and an organic compound described herein with less than the stoichiometric amount of water required for hydrolyzing all of the acyl fluoride in the mixture to the carboxylic acid. This reaction is carried out under conditions whereby the carboxylic acid forms and t~e acid is regenerated as described herein.
In other embodiments of t~e inyention, the process further comprises the step or steps of:
separating from (1~ to one hundred (100) percent of the anhydrous hydrogen fluoride acid from the hydrolyzed mixture and recycling fr~m one ~l) to one hundred ~100) percent of the separated anhydrous acid for reaction with carbon monoxide and the organic compo~nd descri~ed herein to form more of the mixture comprised of the acyl fluoride and the anhydrous acid.
In another embodiment of the invention, the process ; 25 can comprise the step of:
separating from one (1) to one hundred (100) percent of the carboxylic acid from the hydrolyzed mixture, and recycling from one (l) to one hundred (100) percent of the hydrolysis p~oduct mixture remaining after separation of the car~oxylic acid therefrom, for reaction with carbon monoxlde and ~he organic compound described herein to form more of the mixture comprised of the acyl fluoride product.
~6~i'7 _ 3 -REACTANTS
-The xeactants to for~ the acyl fluoride may be from any source, but must be free from deleterious materials which interfere with the process described hereinO ~he total amount of water in the reaction mixture to be hydrolyzed must be less than the stoichiometric a~ount of water re-quired to react with all of the acyl fluoride formed.
The carbon monoxide may be-from any source, but is preferably substantially free from water so as to maintain substantially anhydrous reaction conditions. The carbon monoxide may be diluted with other substances which do not interfere with the reaction. For example, dry synthesis gas or combustion gas may be used. It is preferred that dry carbon monoxide itself be used.
The organic compounds are those which are capable of reacting with carbon monoxide and the anhydrous hydrogen fluoride acid; that is, carbonylated to form an acyl fluoride, for exa~ple, organic esters described herein or organic compounds having at least one double bond capable of carbonyl-ating to an acyl fluoride described herein.
The organic esters are represented by the general Q
formula R - C - 0 - R', whereln R is an alkyl of up to twenty carbon atoms, such as methyl, ethyl, dodecyl, eicosanyl.
Preferably the alkyl is methyl, ethyl, propyl, or isopropyl, with ethyl and isopropyl being the most preferred. R' is an alkyl of from two to twenty carbon atoms, such as ethyl, propyl, t-~utyl, dodecyl, eicosanyl. Preferably R' is ethyl or isopropyl, with isopropyl being the most preferred.
When an organic ester is used in the process described herein, any one of the esters mentioned herein may be used. lt is preferable, however, to use isopropyl :
6" t~ .
, 1~76657 ~ 4 -iso~uty~ate (2-propanol 2-methylpropionatel, ethyl iso~utyrate (ethanol 2-metAylproprionate), lsopropyl propiona~e (2-propanol propionatel or ethyl propionate Cethanol propionate~, and it is espec'ally preferred to ~se isopropyl isobutyrate or ethyl propionate.
Examples of orsanic compounds having at least one dou~le bond capable of forming an acyl fluoride therewith (car~onylating to an acyl fluoridel which may be used in the process described herein are olefins of up to twenty carbon atoms, such as ethylene, propylene, butenes, 1,3-butadiene, and dodecene. The olefins may be su~stituted with alkyl, or aryl, or cycloalkyls, or other su~stituents which do not interfere in the process described herein. Furthermore, the olefins may have multiple double bonds within the molecule lS which does not interfere in the process described herein such as l,3~butadiene. Preferred olefins are ethylene, propylene, isobutene, l-butene, 2-butene, and 1,3-butadiene, and ethylene and propylene are highly preferred.
Although all of the organic compounds described herein may be used in the process described herein, propylene, however, is especially preferred.
The hydrogen fluoride acid used for the preferred process to make the acyl fluoride described herein should be substantially free from water; that is, anhydrous. The term "anhydrous" as used herein and in the claims refers to hydrogen ~luoride acid which is substantially free from water, e.g., less than 2000 parts per million or if water is present, it does not interfere with the reaction to form the acyl anion.
REACTION CONDITIONS
The reaction of car~on monoxide, with an organic compound described herein and the anhydrous hydrogen fluoride acid described herein, can occur at temperatures of from ~1~6657 zero degree Centigrade (:ODCl to one hundred degrees Cen~igrade tlOOC), the upper temperature being determined by side prod~ct formation, For the reaction between the preferred reactants described herein, the temperature can De from forty degrees Centigrade (4QCl to eighty degrees Centigrade ~80C), but preferably it is at a~out sixty degrees Centigrade (60C).
The carbon monoxide pressure can ~ary from one tl) bar ~14.7 psia) to about 40~ bars ~6,0QO psia), but generally it is from 34 bars (500 psia) to 340 bars (5,000 psia), and prefer-ably from 102 bars (1,500 psia) to 136 bars (2,000 psia~, the pressure ~eing increased as required for the solubility of carbon monoxide in the anhydrous acid and to increase the productivity of the reactor.
The mole ratio of anhydro~s acid to the organic compound described herein should be from 1:1 to 100:1, but generally it is from 10:1 to 20:1 and preferably about 15:1.
The mole ratio of carbon monoxide to the orsanic compound described herein is from 1:1 to 5:1 or ~igher, but prefer-ably it is from 1.5:1 to 1:1 and corresponds to the satura-tion limit of carbon monoxide in the reaction mixture during and at the end of the reaction.
All of the carbon monoxide and anhydrous acid, e.g., anhydrous hydrogen fluoride, which is to be reacted with the organic compound, should be thoroughly mixed prior to contacting with the organic compound described herein, e.g., propylene, then the organic compound is rapidly reacted while mixing with the premixed carbon monoxide and acid. Generally, the reaction, depending upon the pressure and the temperature, will occur within minutes to form an acyl fluoride, e.g., isobutyryl fluoride. The organic compound itself can be diluted with carbon monoxide or inert diluents, e.g., propane, prior to reaction with the anhydrous ~76657 acid.
The reaction ~an be condu~ted in a semi-batch reactor-,- plug flow reactor, back mix reactor (CSTR), or other reactor known to those skilled in the art, ~ut the preferred reactor is a plug flow Eeactor.
The hydrolysis reaction of the acyl fluoride, e.g., isobutyryl fluoride, with water can occur at temperatures from twenty degrees Centigrade ~20C) to one hundred fifty degrees Centigrade (150C) and at pressures from 1 bar (14.7 psia) to 340 bars (5,000 psial, but normally it occurs at temperatllres from forty degrees Centigrade (40Cl to seventy degrees Centigrade (70C~ and pressures at 6.8 bars (lQ0 psia) to 2Q4 bars (3,000 psia). The temperature and pressure being set to avoid the decomposition of the intended products, and to facilitate product separations.
~t is preferred that the reactants be stirred during ; hydrolysis. In many cases, when rapid mixing is used, the hydrolysis reaction with the concurrent regeneration of the anhydrous acid, e.g., HF, can be completed within seconds to minutes The critical feature of the hydrolysis reaction is maintaining the mole ratio of water to the acyl fluoride product below 1:1; that is, the total amount of water reacted with ; the mixture comprised of the acylium anion product must be less than the amount of water required for all of the acyl fluoride to form the carboxylic acid.
` The total amount of water ~ay be injected into the mixtu~e comprised of the acyl, but preferably the water is added in partial amounts into the mixture comprised of the acyl fluoride. The hydrolysis step is exothermic, and thus cooling may be required. The mixture may also contain carbon monoxide, unreacted organic compound, anhydrous hydrogen fluoride acid, and carboxylic acid. Preferably the mixture 7 ~76~S7 contains the anhydrous hydrogen fluoride acId, particularly when the acyl fluoEide is sobutyryl fluorlde. ~hen isobutyryl fluoride is hydrolyzed, the ratio of the amo~nt of anhydrous hydrogen ~luoride to iso~utyryl flu~ride is in the range from 0.01 to 95.5 parts by weight of anhy~ro~s hydrogen fluoride ~AHP) to ~9.Q~ ~o 4.5 parts ~y weight of isobutyryl fluoride (IBF), but prefera~ly from la.~ to ~0.0 parts ~y weight of AHF to 9Q to lQ parts by weight of IBF. The amount of an-hydrous hydrogen fluoride acid in the mixture is dependent upon the efficient operation of the process, and the ease of separating the anhydrous hydrogen fluoride acid from the product mixture comprised of the acyl fluoride, e.g., isobutyryl fluoride, hydrogen fluoride, and carbon monoxide.
After the hydrolysis reaction is complete, which depends upon the reaction conditions as known to those skilled in the art, from one (l) to one hundred (100) percent of the carboxylic acid formed is separated from the product mixture of the hydrolysis reaction. Preferably from eighty (80) to one hundred (lO0) percent of the carboxylic acid is separated, and the remaining hydrolysis product mixture is recycled for further reaction with the reactants to form more acyl fluoride product. This recycle stream may contain carbon monoxide and/or anhydrous acid and/or unreacted organic compound and/
or the unhydrolyzed acyl fluoride.
In another embodiment of the invention, from one (1) to one hundred (lO0) percent (preferably from eighty (80) to one hundred (lO0) percent) of the anhydrous hydrogen fluoride acid is separated from the hydrolysis product mixture and is recycled back for reaction to form more acyl fluoride.
Tne recycle stream may contain small amounts of unseparated unhydrolyzed acyl fluoride and/or carboxylic acid and/or unreac~ed organic compound.
~, ~
~76657 The separatlon can be by any of the known methods of separatlon, such as distillation ~r sol~ent extraction.
EXAMPLES
..
The f~llowing e~amples will ilLustrate t~e invention described ~erein.
The following procedure was ~sed to study the hydrolysis of isobutyryl fluoride based on 90 mole percent of the stoichiometric amount of water required to hydrolyze all of the isobutyryl fluoride to isobutyric acid, under semi-adiabatic conditions.
A two liter Hastelloy C Parr reacto~, equipped withwater delivery system (used nitrogen at 5Q0 psia), a thermo-couple connected to a continuous temperature recorder, and an air motor and stirrer adjusted to rotate at l,000 revolutions per minute, was charged with a weighed amount of anhydrous hydrogen fluoride and isobutyryl fluoride (maintained at dry ice-acetone temperature). After charging, the reactants and reactor are brsught to the preselected temperature, and the temperature recorder is started. The weighed amount of water (90 wt.~ of the stoichiometric amount required for reaction of all of the iso~utyryl fluoridel is then ejected. The initial temperature of the water was at room temperature.
After hydrolysis was complete, the mixture was analyzed by gas chromatography. From the temperature-time recording, the temperature rises were noted. Generally, the first was attri-buted to the heat of mixing, and the second was attri~uted to the hydrolysis reac~ion.
Example I
A mixture of 57.6 grams of anhydrous hydro~en 3Q fluoride (lO wt~ percent) and 464.~ grams of isobutyryl fluoride (~0 wt. percent) at 26.8C was hydrol~zed by injecting 83.0 grams of water (at 21C). The reaction mixture tempera-ture rose to 52.4C, then cooled over a 27-second period to 6~i7 _ 9 _ 44C, and then rose exponentially t~ 123C in 4~ seconds. Two phases were obser~ed at the beginnin~ but not at the end of the hydrolysis. The reaction was complete; the analysis showed only isobutyric acid for~ed.
Example II
A mixture of 25.5 grams of anhydro~s hydrogen fluoride ~5 wt. percent) and 488.9 grams of iso~utyryl fluoride ~`95 wt. percent) at 24.1C was hydxolyzed with 87.1 grams of water at 21C. A temperature rise of 13.5C was observedO After twenty minutes when no further temperature rise was noted, the reactor was then externally heated to 51C, and a second temperature rise wlth a temperature change of 78C was obserYed o~er a 99-second inter~al. ~he reaction was complete, the analysis showed only the formation of isobutyric acid.
Exam=ple III
A mixture of 51.6 grams (lQ wt. percent) anhydrous hydrogen fluoride and 464.5 grams (90 wt. percent) isobutyryl fluoride at 223 Centigrade was hydrolyzed by adding 83.2 grams of the water Cat 21C) over a 25-second period. Under these conditions no temperature rise due to mixing was obser~ed.
Instead, the temperature rose continuously from 22 Centigrade to 104 Centigrade, and it was obser~ed that the hydrolysis reaction was limited by the rate of water addition, thus indicating the preferred method of adding water at the ra~e at which hydrolysis occurs. The reaction was complete, the analysis showed only isobutyric acid formed. The experimental heat of hydrolysis calculated about 9.5 kcal per gram of isobutyric acid formed.
Exam~le IV
The following continuous process can be conducted to produce isobutyric acid by the process described herein.
~l~7~6S7 - 10 ~
A plug flow~reactor is used for the formation of iso~utyr~c acid f~om propene. It ~s f~rmed fro~ a forty (40) foot tube having a one-half (~/2) inc~ internal diameter, with a premix section of about five C5) feet and equipped w~th injection points at five-foot intervals ~nd ~ heater. The carbonylation reaction is conducted at 50C and 2,800 psig (192 bars) with propene, anhydrous hydrogen fluoride and carbon monoxide in a mole ratio of 1.0:14:1.3, at a flow rate of 3.2 lbs. per hour (1.52 kilograms per hour). The an-hydrous hydrogen fluoride and carbon monoxide is injectedinto the premix section where they are thoroughly mixed, and the propene is injected into the mixture of anhydrous hydrogen fluoride and carbon monoxide at five-foot intervals, with the final addition being 30 feet from the beginning of the reactor. After the reaction is complete, at the 35-foot injection point, water is injected into the reactor where the hydrolysis occurs preferably at the rate at which hydrolysis occurs and isobutyric acid is formed. The amount of the water injected is less than the amount of isobutyryl fluoride formed. This section of the reactor where the hydrolysis occurs is maintained at approximately 100C and at a pressure of 2,800 psig. The isobutyric acid and any heavy products, such as heavier oligomeric acids (which are less than 3 wt.
percent), are separated from the final product mix~ure by simple distillation, and the remaining isobutyryl fluoride, carbon monoxide and anhydrous hydrogen fluoride is recycled with the carbon monoxide and anhydrous hydrogen fluoride that are being injected lnto the premix section of the reactor.
In another embodiment of the continuous reaction, prior to hydrolysis, the product mixture containing the acyl fluoride (isobutyryl fluoride)is passed to a separation unit - where the excess caxbon monoxide and from ten to ninety percent ~:~7~65~
of the excess anhydxous hydrogen fluoride is remQye~, and recycled, while the re~aining prQduct ~xture preferably haying 10 parts by weight of anhydr~us hyd~Qgen fl~oride to ~0 paxts by weisht of isobutyryl fluoxide is hydxolyzed as described hexein followed by separation of isobutyric acid and recycling of the remaining product mixture of unreacted isobutyxyl fluoride and anhydrous hydrogen fluoride.
While the invention has been described with refer-ence to specific details of certain illustrative embodiments, it.is not intended that it shall be limited thereby except insofar as such details appear in the accompanying claims~
Claims (16)
1. A process for producing a carboxylic acid from an acyl fluoride product which comprises:
hydrolyzing a mixture comprised of an acyl fluoride with less than the stoichiometric amount of water required for hydrolyzing all of the acyl fluoride in the mixture to the carboxylic acid under conditions whereby the carboxylic acid forms and the acid is re-generated from the anion;
said acyl fluoride being formed from the reaction of carbon monoxide, anhydrous hydrogen fluoride acid and an organic compound capable of reacting with the carbon monoxide and anhydrous fluoride acid, under conditions whereby an acyl fluoride forms;
the organic compound being selected from the group consisting of (1) an ester represented by the general formula , wherein R is an alkyl of up to twenty carbon atoms, and R' is an alkyl of from two to twenty carbon atoms, and (2) an olefin of up to twenty carbon atoms having at least one double bond capable of forming an acylium anion product therewith;
the temperature of hydrolysis being from twenty degrees Centigrade (20°C) to one hundred fifty degrees Centigrade (150°C) and at pressures from one (1) bar (14.7 psia) to three hundred forty (340) bars (5,000 psia);
the ratio of the anhydrous hydrogen fluoride to the acyl fluoride being within the range of from one hundredth (0.01) to ninety-five and five tenths (95.5) parts by weight of anhydrous hydrogen fluoride to ninety-nine and nine hundredths (99.09) to four and five tenths (4.5) parts by weight to the acyl fluoride.
hydrolyzing a mixture comprised of an acyl fluoride with less than the stoichiometric amount of water required for hydrolyzing all of the acyl fluoride in the mixture to the carboxylic acid under conditions whereby the carboxylic acid forms and the acid is re-generated from the anion;
said acyl fluoride being formed from the reaction of carbon monoxide, anhydrous hydrogen fluoride acid and an organic compound capable of reacting with the carbon monoxide and anhydrous fluoride acid, under conditions whereby an acyl fluoride forms;
the organic compound being selected from the group consisting of (1) an ester represented by the general formula , wherein R is an alkyl of up to twenty carbon atoms, and R' is an alkyl of from two to twenty carbon atoms, and (2) an olefin of up to twenty carbon atoms having at least one double bond capable of forming an acylium anion product therewith;
the temperature of hydrolysis being from twenty degrees Centigrade (20°C) to one hundred fifty degrees Centigrade (150°C) and at pressures from one (1) bar (14.7 psia) to three hundred forty (340) bars (5,000 psia);
the ratio of the anhydrous hydrogen fluoride to the acyl fluoride being within the range of from one hundredth (0.01) to ninety-five and five tenths (95.5) parts by weight of anhydrous hydrogen fluoride to ninety-nine and nine hundredths (99.09) to four and five tenths (4.5) parts by weight to the acyl fluoride.
2. The process as recited in Claim 1 wherein the organic compound is an ester selected from the group consisting of isopropyl isobutyrate, ethyl isobutyrate, isopropyl propionate, and ethyl propionate.
3. The process as recited in Claim 1 wherein the organic compound is an ester selected from the group consisting of isopropyl isobutyrate and ethyl propionate.
4. The process as recited in Claim 1 wherein the organic compound is an olefin of up to twenty carbon atoms having at least one double bond capable of forming an acyl fluoride therewith.
5. The process as recited in Claim 1 wherein the olefin is selected from the group consisting of ethylene, propylene, isobutene, 1-butene, 2-butene, and 1,3-butadiene.
6. The process as recited in Claim 1 wherein the olefin is ethylene.
7. The process as recited in Claim 1 wherein the olefin is propylene and the acyl fluoride is isobutyryl fluoride.
8. The process as recited in Claim 7 wherein the amount of water added is from seventy (70) to ninety-nine (99) percent of the amount of the isobutyryl fluoride.
9. The process as recited in Claim 8 wherein the initial amount of anhydrous hydrogen fluoride in the mixture being hydrolyzed is from ten to ninety parts by weight and the initial amount of isobutyryl fluoride in the mixture being hydrolyzed is from ten to ninety parts by weight.
10. The process as recited in claim 1 wherein from eighty (80) to one hundred (100) percent of the formed carboxylic acid is separated from the product mixture and the remaining product mixture comprised of anhydrous hydrogen fluoride is recycled for further reaction with carbon monoxide and the organic compound to form more acyl fluoride.
11. A process for producing isobutyric acid from isobutyryl fluoride which comprises:
reacting a liquid mixture comprised of anhydrous hydrogen fluoride and isobutyryl fluoride with less than the total amount of water required for hydrolyzing all of the isobutyrul fluoride to isobutyric acid, the starting amount of anhydrous hydrogen fluoride being from one hundredth (0.01) to ninety-five and five tenths (95.5) parts by eight of anhydrous hydrogen fluoride to ninety-nine and nine hundredths (99.09) to four and five tenths (4.5) parts by weight of isobutyl fluoride, the reaction being conducted at a temperature from twenty degrees Centigrade (20°C) to one hundred and fifty degrees Centigrade (150 C), and at a pressure whereby the reaction occurs in the liquid phase, said reaction being continued until all of the water substantially reacts to form isobutyric acid.
reacting a liquid mixture comprised of anhydrous hydrogen fluoride and isobutyryl fluoride with less than the total amount of water required for hydrolyzing all of the isobutyrul fluoride to isobutyric acid, the starting amount of anhydrous hydrogen fluoride being from one hundredth (0.01) to ninety-five and five tenths (95.5) parts by eight of anhydrous hydrogen fluoride to ninety-nine and nine hundredths (99.09) to four and five tenths (4.5) parts by weight of isobutyl fluoride, the reaction being conducted at a temperature from twenty degrees Centigrade (20°C) to one hundred and fifty degrees Centigrade (150 C), and at a pressure whereby the reaction occurs in the liquid phase, said reaction being continued until all of the water substantially reacts to form isobutyric acid.
12. The process as recited in Claim 11 wherein the amount of water reacted in from seventy (70) to ninety-nine (99) mole percent of the isobutyryl fluoride in the mixture.
13. The process as recited in Claim 12 wherein the amount of anhydrous hydrogen fluoride in the liquid mixture is from ten to ninety parts by weight and the starting amount of isobutyryl fluoride in the liquid mixture is from ten to ninety parts by weight.
14. The process as recited in any of Claims 11, 12 or 13 wherein the pressure is from six and eight tenths (6.8) bars (100 psia) to three hundred and forty (340) bars (5,000 psia).
15. The process as recited in claim 11 wherein the isobutyric acid is separated by distillation.
16. The process as recited in Claim 13 wherein the isobutyric acid is separated by distillation.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US27069881A | 1981-06-05 | 1981-06-05 | |
| US270,698 | 1981-06-05 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1176657A true CA1176657A (en) | 1984-10-23 |
Family
ID=23032417
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000404467A Expired CA1176657A (en) | 1981-06-05 | 1982-06-04 | Production of carboxylic acids from acylium anions formed by carbonylation |
Country Status (12)
| Country | Link |
|---|---|
| JP (1) | JPS6024086B2 (en) |
| KR (1) | KR850001913B1 (en) |
| AT (1) | AT389694B (en) |
| AU (1) | AU532972B2 (en) |
| BE (1) | BE893417A (en) |
| CA (1) | CA1176657A (en) |
| CH (1) | CH657122A5 (en) |
| DE (1) | DE3221174C2 (en) |
| FR (1) | FR2507179A1 (en) |
| GB (2) | GB2099821B (en) |
| IT (1) | IT1210894B (en) |
| NL (1) | NL186959C (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE3332436T1 (en) * | 1982-02-18 | 1984-12-13 | Ashland Oil Inc., Columbus, Ohio | Formation of isobutyric acid or methyl isobutyrate |
| DE3213395A1 (en) * | 1982-04-10 | 1983-10-13 | Röhm GmbH, 6100 Darmstadt | METHOD FOR PRODUCING ISOBUTTERIC ACID FLUORIDE OR ISOBUTTERIC ACID |
| JPH07327833A (en) * | 1994-06-07 | 1995-12-19 | Morii Kinzoku Kogyo Kk | Container for pan and water heater, etc. |
Family Cites Families (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| NL302250A (en) * | 1963-01-21 | |||
| GB1120714A (en) * | 1965-07-22 | 1968-07-24 | Distillers Co Yeast Ltd | Improvements in or relating to the production of carboxylic acids |
| NL6816940A (en) * | 1967-11-28 | 1969-05-30 | ||
| BE755997A (en) * | 1969-09-11 | 1971-03-10 | Bp Chem Int Ltd | PRODUCTION OF DICARBOXYLIC ACIDS |
| US3661951A (en) * | 1969-12-01 | 1972-05-09 | Armour Ind Chem Co | Carboxylation of olefins |
| DE2406223A1 (en) * | 1974-02-09 | 1975-08-21 | Basf Ag | Acid-catalysed carbonylation of olefins and alcohols to acids - with reaction mixt cycled through a cooled external circuit for temp control |
| EP0031886B1 (en) * | 1979-12-20 | 1984-04-11 | Röhm Gmbh | Process for the production of isobutyric acid or its lower alkyl esters |
-
1982
- 1982-06-04 CH CH3475/82A patent/CH657122A5/en not_active IP Right Cessation
- 1982-06-04 AU AU84606/82A patent/AU532972B2/en not_active Ceased
- 1982-06-04 DE DE3221174A patent/DE3221174C2/en not_active Expired
- 1982-06-04 NL NLAANVRAGE8202270,A patent/NL186959C/en not_active IP Right Cessation
- 1982-06-04 FR FR8209807A patent/FR2507179A1/en active Granted
- 1982-06-04 BE BE0/208269A patent/BE893417A/en not_active IP Right Cessation
- 1982-06-04 GB GB8216301A patent/GB2099821B/en not_active Expired
- 1982-06-04 KR KR8202509A patent/KR850001913B1/en active
- 1982-06-04 CA CA000404467A patent/CA1176657A/en not_active Expired
- 1982-06-04 IT IT8221708A patent/IT1210894B/en active
- 1982-06-04 JP JP57096067A patent/JPS6024086B2/en not_active Expired
- 1982-06-07 AT AT0220282A patent/AT389694B/en not_active IP Right Cessation
-
1984
- 1984-02-09 GB GB08403476A patent/GB2134113B/en not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| GB8403476D0 (en) | 1984-03-14 |
| GB2099821B (en) | 1985-10-23 |
| GB2134113A (en) | 1984-08-08 |
| FR2507179B1 (en) | 1985-05-17 |
| CH657122A5 (en) | 1986-08-15 |
| ATA220282A (en) | 1989-06-15 |
| GB2099821A (en) | 1982-12-15 |
| IT1210894B (en) | 1989-09-29 |
| KR850001913B1 (en) | 1985-12-31 |
| DE3221174C2 (en) | 1985-06-20 |
| GB2134113B (en) | 1985-11-20 |
| NL186959B (en) | 1990-11-16 |
| KR840000462A (en) | 1984-02-22 |
| JPS6024086B2 (en) | 1985-06-11 |
| AU532972B2 (en) | 1983-10-20 |
| JPS57212134A (en) | 1982-12-27 |
| BE893417A (en) | 1982-10-01 |
| IT8221708A0 (en) | 1982-06-04 |
| FR2507179A1 (en) | 1982-12-10 |
| NL186959C (en) | 1991-04-16 |
| NL8202270A (en) | 1983-01-03 |
| AU8460682A (en) | 1982-12-09 |
| DE3221174A1 (en) | 1982-12-23 |
| AT389694B (en) | 1990-01-10 |
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