CA1183868A - Process for the production of 3,3-dimethylglutaric acid - Google Patents
Process for the production of 3,3-dimethylglutaric acidInfo
- Publication number
- CA1183868A CA1183868A CA000402662A CA402662A CA1183868A CA 1183868 A CA1183868 A CA 1183868A CA 000402662 A CA000402662 A CA 000402662A CA 402662 A CA402662 A CA 402662A CA 1183868 A CA1183868 A CA 1183868A
- Authority
- CA
- Canada
- Prior art keywords
- acid
- isophorone
- hydrogen peroxide
- strong
- strong acid
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C51/00—Preparation of carboxylic acids or their salts, halides or anhydrides
- C07C51/16—Preparation of carboxylic acids or their salts, halides or anhydrides by oxidation
- C07C51/285—Preparation of carboxylic acids or their salts, halides or anhydrides by oxidation with peroxy-compounds
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Oil, Petroleum & Natural Gas (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
- Acyclic And Carbocyclic Compounds In Medicinal Compositions (AREA)
- Detergent Compositions (AREA)
- Low-Molecular Organic Synthesis Reactions Using Catalysts (AREA)
Abstract
ABSTRACT OF THE DISCLOSURE
Process for the production of 3,3-dimethylglutaric acid from isophorone. The isophorone is treated with hydrogen peroxide in the presence of a strong acid at a temperature of 10° to 80°C. The preferred acid is sulfuric acid, and the reaction is preferably conducted at a temperature of 20° to 50°C. Preferably the molar ratio of isophorone to hydrogen peroxide to strong acid is 1:4 to 8:4 to 8.
Process for the production of 3,3-dimethylglutaric acid from isophorone. The isophorone is treated with hydrogen peroxide in the presence of a strong acid at a temperature of 10° to 80°C. The preferred acid is sulfuric acid, and the reaction is preferably conducted at a temperature of 20° to 50°C. Preferably the molar ratio of isophorone to hydrogen peroxide to strong acid is 1:4 to 8:4 to 8.
Description
:~ACKGROIJND O~ T~E I~VE~;iTION
1. Field of the I~ventlon .
The in~en-tion rel~tes to a prQ~ess far the production of 3,3-dlmet'hylglut~ric acid from isophorone.
1. Field of the I~ventlon .
The in~en-tion rel~tes to a prQ~ess far the production of 3,3-dlmet'hylglut~ric acid from isophorone.
2. prior Art It is known to the art to treat isophorone with H2O2 in an alkaline medium (R. D. Temple, J. Org. Chem., 35, 1275). In that case a yield of 92 percent of 3,3-dimethyl-5-oxo-hexanoic acid is obtained. On the other hand, various methods are known from the lite~a~ure for ~e productlon of 3,3-dimethylglutaric acid. Thus, accordlng to W. T. Smith and G. L. McLeo_, Org.
Synthesis 31, 40 (1951), 3,3-dimethylglutaric acid is obtained by oxidation of dimedone (5,5-dimethyl-1,3-cyclohexanedione) with sodium hypochlorite. F.~ B. Thole and J. F. Thorpe, J.
Chem. Soc. 99, 422 (1911), shows obtaining 3,3-dimethylglutaric acid ~rom acetone and cyanoacetamide. - W ~ _ , and J. F. Thorpe, J. Chem. Soc. _, 48 (I899), shows the production of 3,3-dimethylglutaric acid from dimethylacrylic ester and cyanoacetic ester.
All of such known processes have disadvantages, for example, they start out with expensive educts or pass over several steps of synthesis or produce low yields, have large amounts of waste salt a~ a byproduct or deliver a greatly contaminated end product.
B~OA:D DESCRIPTION OF T~IE; INyENT:~O~
It is an objec~ of ~he invention to provide a process for producing 3,3-dime-~hyl~lutaric acidr starting out with isophorone, in a simple manner. Other objects and advantages of the invention are set out herein or are obvious herefrom to one ordinar~ly skilled in the art.
The objects and advantages of the invention are achieved by the process and composition of the invention.
The invention involves a process for the production of
Synthesis 31, 40 (1951), 3,3-dimethylglutaric acid is obtained by oxidation of dimedone (5,5-dimethyl-1,3-cyclohexanedione) with sodium hypochlorite. F.~ B. Thole and J. F. Thorpe, J.
Chem. Soc. 99, 422 (1911), shows obtaining 3,3-dimethylglutaric acid ~rom acetone and cyanoacetamide. - W ~ _ , and J. F. Thorpe, J. Chem. Soc. _, 48 (I899), shows the production of 3,3-dimethylglutaric acid from dimethylacrylic ester and cyanoacetic ester.
All of such known processes have disadvantages, for example, they start out with expensive educts or pass over several steps of synthesis or produce low yields, have large amounts of waste salt a~ a byproduct or deliver a greatly contaminated end product.
B~OA:D DESCRIPTION OF T~IE; INyENT:~O~
It is an objec~ of ~he invention to provide a process for producing 3,3-dime-~hyl~lutaric acidr starting out with isophorone, in a simple manner. Other objects and advantages of the invention are set out herein or are obvious herefrom to one ordinar~ly skilled in the art.
The objects and advantages of the invention are achieved by the process and composition of the invention.
The invention involves a process for the production of
3,3-dimethylglutaric acid from isophorone. In the process the isophoron~ is treated with hydrogen peroxide in the presence of a strong acid at a temperature of 10 to 80C. The preferred strong acid is sulfuric acid. The molar ratio of isophorone to hydrogen peroxide to strong acid is preferably 1:4 to 8:4 to 8.
Preferably the reaction is conducted at a temperature of 20 to 50C.
The invention also includes a composition composed of isophorone, hydrogen peroxide, a strong acid and water.
3,3-dimethyl~lutaric acid and its esters are intermediate 20 products in the production of pesticides (see German OS 2813341).
Furthermore, they are useful as additives for lubricating oil (see U. S. Patent No. 2,971,915).
DETAILED D~S'ÇR:~PTXON OF TEIE INVE~TION
~ he inv~ntion invol~es -the Production of 3,3-dimethyl-glutaric acid ~ro~ i~ophorone, which has the ~ormula:
CH
f ~C
( , ~ CH3 o~(~\ / \ CH3 Isophorone is also ter~ed isoacetophorone and 3,5,5,-trimethyl-2-cyclohexen-1-one.
The isophorone is treated with hydrogen peroxide in the presence of a strong acid at a temperature from 10 to 80C.
The reaction temperature is preferably between 20 and 50C~
Protonic acids (Broensted acids) are examples of useful strong acids. Such protonic acids have a pKa-value of 2.5 or less and are stable against hydrogen peroxide. Examples of such protonic acids are sulphuric acid, phosphoric acid, nitric acid, and organic sulfonic acids, such as benzene sulfonic acid, txichloroacetic acid and trifluroacetic acid. Sulfuric acid is pre~erred~ The strong acid can be used in its pure form or as an aqueous solution. When sulfuric acid is used as the strong acidl industrial concentrated sulfuric acid is preferably used.
To carry out the reaction, a mixture of water, hydrogen peroxide and a s~rong acid is preferred in a first step, b~
co~bining a solu-tion of hydrogen peroxide, a strong acid or an aqueous solution of a strong acid and possibly water. Hydrogen peroxide is used in the for~ of an aqueous solution, wherein the concentration can ~ary within a wide range of about 20 to about 85 percent Industrially obtainable concentrations of 30 to 70 percent o~ H2O~in water are preferred.
The quan~lties and the concentrations of hydrogen peroxide solution, strong acids and possibly water are selected such that fQr 1 mole of isophorone there are 4 to 8 moles of hydrogen peroxide, 4 to 8 moles o~ strong acid and 20 to 40 moles of water. The preferred ratio lies at 5 to 6 moles of hydrogen peroxide, 5 to 6 moles of sulfuric acid and 30 moles of water for 1 mole of isophorone.
According to the process of the invention, 3,3-dimethyl-glutaric acid is obtained in a purity of over 80 percent and a-t a yield of up to over 75 percent.
By way of summary, in the process of the invention 3,3-dimethylglutaxic acid is produced by treatment of isophorone with H2O2 in the presence of ~ strong acid or acids.
As used herein, all parts, percentages, ratios and proportions are on a weight basis unless otherwise stated herein or otherwise obviou~ herefrom to one ordinarily skilled in the art.
EX~MP~E_l In a three-necked ;Elask, 166.3 g of 95 percent H2SO4 was inserted. 2ao g of 30 percent hydro~en peroxide was added drop by drop while copling to ~' 10C. During one hour 40 g of isophorone (99 percent pure) Was added in doses such that the temperature remained cons-tant at 25C. After the addition, the tempexatuxe was increa~ed pr~gressively to 58C. At that temperature the reaction mixture was stirred for another 16 hours. The mixture wa~ cooled to -10~C. and the crystal-paste was filtered o~f b~ suction. The crystals contained 23.32 g of 3,3-dimethylglutaric acid. The purity of the product was 82 percent.
~he ~other lye (a~ter destruction of peroxide by blowing throu~h of SO2) was extracted after the addition of concen-trated NaOH, three times up to 1.5 pH, with 120 ml of ether.
The extract, a~ter eyaporating of ether, still contained 7.4 g of 3,3-dimethylglutaric acid, considered as 100 percent pure.
The total yield, reIated to the quantity of isophorone used, amounted to 57.8 percent.
In a three-necked $1ask, 280 g of 56 percent H2SO~ was inserted. 85 ~ o 70 peXcent hydrogen peroxide was added drop by drop while cooling ~Q ^'10C. During one hour 40 g of isophorone was added in doses such that the temperature remained between 25 and 30~C. Aftex the addition, the temperature was inCxeased pro~ressively to 58C. At tha-t temperature the reaction mixture was stirred for another 5 hours.
The mixture was cooled slowly to -10C. and the crystal paste was iltered o~ ~y suction. The crystals contained 29.7 g o 3,3-dimethyl~lutaric acid with a content o~ 82.3 percent of GC, with an intexnal standard, which corresponds to 24.44 of 3,~-dimethylglutclric acid ~ormed.
The mother lye (after destruction o~ peroxide by blowing S2 through it), aftex addition of concentrated ~aOH up to a pH 1~5, was extracted thxee times with 120 ml of ether.
After eVaporatiQn a~othe~ 7.S0 g of 3,3-dimethylglutaric acid was found with GC in the extract. All together, 31.94 g of 3,3-dimethylglutaric acid was formed, which corresponds to a yield of 68.9 percent, related to the isophorone used.
~AMPLE 3 83 g of 85 percent phosphoric acid was inserted into a flask. 100 g of 30 perce~t hydrogen peroxide was added drop by drop. During one hour, 20 g of isophorone was added in doses such that the temperature remained between 25 to 35C.
After completion of the addition, the reaction mixture was continued to be stirred at ambient temperature. The temperature in the flask at first rose to 50 to 55C., then it dropped slowly during a 3 to 5 hour period.
The colorless ~o light yello~ solution was freed of peroxides by ~reatment with SO2 and the pH value was adjusted to 1.5 with concentrated NaOH. The 3,3-dimethylglutaric acid formed Was isolated by extraction with ether. According to the gas-chromatographic analysis, the residue after evaporation contained 8.87 g o~ 3,3-dimethylglutaric acid, which corresponds to a yield of 38.3 percent, related to the isophorone used.
Preferably the reaction is conducted at a temperature of 20 to 50C.
The invention also includes a composition composed of isophorone, hydrogen peroxide, a strong acid and water.
3,3-dimethyl~lutaric acid and its esters are intermediate 20 products in the production of pesticides (see German OS 2813341).
Furthermore, they are useful as additives for lubricating oil (see U. S. Patent No. 2,971,915).
DETAILED D~S'ÇR:~PTXON OF TEIE INVE~TION
~ he inv~ntion invol~es -the Production of 3,3-dimethyl-glutaric acid ~ro~ i~ophorone, which has the ~ormula:
CH
f ~C
( , ~ CH3 o~(~\ / \ CH3 Isophorone is also ter~ed isoacetophorone and 3,5,5,-trimethyl-2-cyclohexen-1-one.
The isophorone is treated with hydrogen peroxide in the presence of a strong acid at a temperature from 10 to 80C.
The reaction temperature is preferably between 20 and 50C~
Protonic acids (Broensted acids) are examples of useful strong acids. Such protonic acids have a pKa-value of 2.5 or less and are stable against hydrogen peroxide. Examples of such protonic acids are sulphuric acid, phosphoric acid, nitric acid, and organic sulfonic acids, such as benzene sulfonic acid, txichloroacetic acid and trifluroacetic acid. Sulfuric acid is pre~erred~ The strong acid can be used in its pure form or as an aqueous solution. When sulfuric acid is used as the strong acidl industrial concentrated sulfuric acid is preferably used.
To carry out the reaction, a mixture of water, hydrogen peroxide and a s~rong acid is preferred in a first step, b~
co~bining a solu-tion of hydrogen peroxide, a strong acid or an aqueous solution of a strong acid and possibly water. Hydrogen peroxide is used in the for~ of an aqueous solution, wherein the concentration can ~ary within a wide range of about 20 to about 85 percent Industrially obtainable concentrations of 30 to 70 percent o~ H2O~in water are preferred.
The quan~lties and the concentrations of hydrogen peroxide solution, strong acids and possibly water are selected such that fQr 1 mole of isophorone there are 4 to 8 moles of hydrogen peroxide, 4 to 8 moles o~ strong acid and 20 to 40 moles of water. The preferred ratio lies at 5 to 6 moles of hydrogen peroxide, 5 to 6 moles of sulfuric acid and 30 moles of water for 1 mole of isophorone.
According to the process of the invention, 3,3-dimethyl-glutaric acid is obtained in a purity of over 80 percent and a-t a yield of up to over 75 percent.
By way of summary, in the process of the invention 3,3-dimethylglutaxic acid is produced by treatment of isophorone with H2O2 in the presence of ~ strong acid or acids.
As used herein, all parts, percentages, ratios and proportions are on a weight basis unless otherwise stated herein or otherwise obviou~ herefrom to one ordinarily skilled in the art.
EX~MP~E_l In a three-necked ;Elask, 166.3 g of 95 percent H2SO4 was inserted. 2ao g of 30 percent hydro~en peroxide was added drop by drop while copling to ~' 10C. During one hour 40 g of isophorone (99 percent pure) Was added in doses such that the temperature remained cons-tant at 25C. After the addition, the tempexatuxe was increa~ed pr~gressively to 58C. At that temperature the reaction mixture was stirred for another 16 hours. The mixture wa~ cooled to -10~C. and the crystal-paste was filtered o~f b~ suction. The crystals contained 23.32 g of 3,3-dimethylglutaric acid. The purity of the product was 82 percent.
~he ~other lye (a~ter destruction of peroxide by blowing throu~h of SO2) was extracted after the addition of concen-trated NaOH, three times up to 1.5 pH, with 120 ml of ether.
The extract, a~ter eyaporating of ether, still contained 7.4 g of 3,3-dimethylglutaric acid, considered as 100 percent pure.
The total yield, reIated to the quantity of isophorone used, amounted to 57.8 percent.
In a three-necked $1ask, 280 g of 56 percent H2SO~ was inserted. 85 ~ o 70 peXcent hydrogen peroxide was added drop by drop while cooling ~Q ^'10C. During one hour 40 g of isophorone was added in doses such that the temperature remained between 25 and 30~C. Aftex the addition, the temperature was inCxeased pro~ressively to 58C. At tha-t temperature the reaction mixture was stirred for another 5 hours.
The mixture was cooled slowly to -10C. and the crystal paste was iltered o~ ~y suction. The crystals contained 29.7 g o 3,3-dimethyl~lutaric acid with a content o~ 82.3 percent of GC, with an intexnal standard, which corresponds to 24.44 of 3,~-dimethylglutclric acid ~ormed.
The mother lye (after destruction o~ peroxide by blowing S2 through it), aftex addition of concentrated ~aOH up to a pH 1~5, was extracted thxee times with 120 ml of ether.
After eVaporatiQn a~othe~ 7.S0 g of 3,3-dimethylglutaric acid was found with GC in the extract. All together, 31.94 g of 3,3-dimethylglutaric acid was formed, which corresponds to a yield of 68.9 percent, related to the isophorone used.
~AMPLE 3 83 g of 85 percent phosphoric acid was inserted into a flask. 100 g of 30 perce~t hydrogen peroxide was added drop by drop. During one hour, 20 g of isophorone was added in doses such that the temperature remained between 25 to 35C.
After completion of the addition, the reaction mixture was continued to be stirred at ambient temperature. The temperature in the flask at first rose to 50 to 55C., then it dropped slowly during a 3 to 5 hour period.
The colorless ~o light yello~ solution was freed of peroxides by ~reatment with SO2 and the pH value was adjusted to 1.5 with concentrated NaOH. The 3,3-dimethylglutaric acid formed Was isolated by extraction with ether. According to the gas-chromatographic analysis, the residue after evaporation contained 8.87 g o~ 3,3-dimethylglutaric acid, which corresponds to a yield of 38.3 percent, related to the isophorone used.
Claims (15)
- WHAT IS CLAIMED IS:
l. Process for the production of 3,3-dimethylglutaric acid from isophorone which comprises treating isophorone with hydrogen peroxide in the presence of a strong acid at a temperature of 10° to 80°C. - 2. Process as claimed in Claim l wherein the reaction is conducted at a temperature of 20° to 50°C.
- 3. Process as claimed in Claim 2 wherein the strong acid is a protonic acid.
- 4. Process as claimed in Claim 2 wherein the strong acid is sulfuric acid, nitric acid, phosphoric acid or an organic sulfonic acid.
- 5. Process as claimed in Claim 2 wherein the strong acid is sulfuric acid.
- 6. Process as claimed in Claim 2 wherein the molar ratio of isophorone to hydrogen peroxide is 1:4 to 8:4 to 8.
- 7. Process as claimed in Claim l wherein the strong acid is sulfuric acid.
- 8. Process as claimed in Claim l wherein the molar ratio of isophorone to hydrogen peroxide to strong acid is 1:4 to 8:4 to 8.
- 9. Process as claimed in Claim 8 wherein the reaction is operated at a temperature of 20° to 50°C. and the strong acid is a protonic acid.
- 10. Composition consisting essentially of isophorone, hydrogen peroxide, at least one strong acid and water.
- 11. Composition as claimed in Claim 10 wherein the strong acid is a protonic acid.
- 12. Composition as claimed in Claim 11 wherein the protonic acid is sulfuric acid.
- 13. Composition consisting of isophorone, hydrogen peroxide, at least one strong acid and water, and the molar ratio of isophorone to hydrogen peroxide to strong acid is 1:4 to 8:4 to 8.
- 14. Composition as claimed in Claim 13 wherein the strong acid is protonic acid.
- 15. Composition as claimed in Claim 14 wherein the protonic acid is sulfuric acid.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CH3062/81A CH650762A5 (en) | 1981-05-12 | 1981-05-12 | METHOD FOR PRODUCING 3,3-DIMETHYLGLUTARIC ACID. |
| CH3062/81 | 1981-05-12 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1183868A true CA1183868A (en) | 1985-03-12 |
Family
ID=4247770
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000402662A Expired CA1183868A (en) | 1981-05-12 | 1982-05-11 | Process for the production of 3,3-dimethylglutaric acid |
Country Status (11)
| Country | Link |
|---|---|
| EP (1) | EP0064633B1 (en) |
| JP (1) | JPS57192330A (en) |
| AT (1) | ATE9324T1 (en) |
| CA (1) | CA1183868A (en) |
| CH (1) | CH650762A5 (en) |
| DD (1) | DD202141A5 (en) |
| DE (1) | DE3260707D1 (en) |
| DK (1) | DK197982A (en) |
| HU (1) | HU190009B (en) |
| IL (1) | IL65734A (en) |
| SU (1) | SU1099841A3 (en) |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB740747A (en) * | 1951-08-18 | 1955-11-16 | Distillers Co Yeast Ltd | Preparation of alpha-omega-dicarboxylic acids |
-
1981
- 1981-05-12 CH CH3062/81A patent/CH650762A5/en not_active IP Right Cessation
-
1982
- 1982-04-21 AT AT82103380T patent/ATE9324T1/en not_active IP Right Cessation
- 1982-04-21 EP EP82103380A patent/EP0064633B1/en not_active Expired
- 1982-04-21 DE DE8282103380T patent/DE3260707D1/en not_active Expired
- 1982-05-03 DK DK197982A patent/DK197982A/en unknown
- 1982-05-10 DD DD82239719A patent/DD202141A5/en unknown
- 1982-05-10 HU HU821458A patent/HU190009B/en unknown
- 1982-05-11 IL IL65734A patent/IL65734A/en not_active IP Right Cessation
- 1982-05-11 SU SU3433200A patent/SU1099841A3/en active
- 1982-05-11 CA CA000402662A patent/CA1183868A/en not_active Expired
- 1982-05-11 JP JP57079086A patent/JPS57192330A/en active Pending
Also Published As
| Publication number | Publication date |
|---|---|
| HU190009B (en) | 1986-08-28 |
| IL65734A (en) | 1986-01-31 |
| EP0064633A1 (en) | 1982-11-17 |
| JPS57192330A (en) | 1982-11-26 |
| DD202141A5 (en) | 1983-08-31 |
| CH650762A5 (en) | 1985-08-15 |
| ATE9324T1 (en) | 1984-09-15 |
| SU1099841A3 (en) | 1984-06-23 |
| DK197982A (en) | 1982-11-13 |
| IL65734A0 (en) | 1982-08-31 |
| DE3260707D1 (en) | 1984-10-18 |
| EP0064633B1 (en) | 1984-09-12 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEC | Expiry (correction) | ||
| MKEX | Expiry |