GB2060612A - Process for Preparing p-tert- Butyl Benzaldehyde - Google Patents
Process for Preparing p-tert- Butyl Benzaldehyde Download PDFInfo
- Publication number
- GB2060612A GB2060612A GB8024137A GB8024137A GB2060612A GB 2060612 A GB2060612 A GB 2060612A GB 8024137 A GB8024137 A GB 8024137A GB 8024137 A GB8024137 A GB 8024137A GB 2060612 A GB2060612 A GB 2060612A
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- Prior art keywords
- nitrate
- cerium
- tert
- mixture
- fatty acid
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C45/00—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds
- C07C45/27—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by oxidation
- C07C45/28—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by oxidation of CHx-moieties
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25B—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES FOR THE PRODUCTION OF COMPOUNDS OR NON-METALS; APPARATUS THEREFOR
- C25B3/00—Electrolytic production of organic compounds
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25B—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES FOR THE PRODUCTION OF COMPOUNDS OR NON-METALS; APPARATUS THEREFOR
- C25B3/00—Electrolytic production of organic compounds
- C25B3/20—Processes
- C25B3/23—Oxidation
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- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
- Electrolytic Production Of Non-Metals, Compounds, Apparatuses Therefor (AREA)
Abstract
p-tert-Butyl benzaldehyde is prepared by performing at least once the steps of (a) electrolyzing cerium (III) nitrate or ammonium cerium (III) nitrate to obtain cerium (IV) nitrate or ammonium cerium (IV) nitrate in a mixture of water and an aliphatic acid, and (b) oxidizing p-tert-butyl toluene with the Ce(IV)-containing mixture.
Description
SPECIFICATION
Process for Preparing p-Tert-butyl Benzaldehyde
This invention relates to a process for preparing p-tert-butyl benzaldehyde.
p-tert-Butyl benzaldehyde is an important compound, for example, as a material for preparing perfumes. Heretofore known as processes for preparing p-tert butyl benzaldehyde by the oxidation of p-tert butyl toluene are a process in which the toluene is oxidized with manganese dioxide and an automatic oxidation process which uses a cobalt-bromine system. These processes nevertheless give a large amount of further oxidized p-tert-butyl benzoic acid as a by-product if it is attempted to achieve an increased conversion, involve difficulties in treating the oxidizing agent and catalyst for disposal and require a cumbersome procedure for the regeneration of these materials.
It is also generally known to oxidize a methyl on a benzene nucleus with an oxidizing agent or air.
However, the use of chemical oxidizing agents, such as potassium permanganate and potassium dichromate, entails many problems in respect of pollution, toxicity, economy, etc. Furthermore, the use of air necessitates a special catalyst, affords a low yield, involves problems in the treatment of the byproduct and catalyst and requires a special treatment, such as a reaction at a high temperature and a high pressure, which imposes problems also on the apparatus.
Tetrahedron Letter, 1966, 4493 discloses that p-methyl anisole is oxidized with ammonium cerium(lV) nitrate in an aqueous solution of nitric acid, acetic acid, perchloric acid or the like to obtain anisaldehyde. In this case, the product is isolated in the form of the corresponding 2,4dinitrophenylhydrazone compound. We practiced this process with full care exactly in the same manner as disclosed for the oxidation of p-methyl anisole. Separation and detailed analysis of the reaction mixture revealed that the process afforded 43% of anisaldehyde, 1 6% of a quinone compound which appeared to have resulted from the oxidation coupling of the starting material and anisaldehyde formed as a product, and various other by-products of unidentified structure.With the disclosed process, no attempt whatever is made to use the oxidizing agent in circulation. The literature says nothing about the electrolytic oxidation of the oxidizing agent after the oxidation reaction with the use of the same solvent, or about any method of effectively separating the desired product.
German Offenlegungsschrift No. 1,804,727 discloses oxidation of naphthalene, anthracene or the like with cerium (IV) sulfate or ammonium cerium(lV) sulfate in an aqueous solution of sulfuric acid or nitric acid for the preparation of a quinone, and regeneration of the resulting cerium salt by electrolysis. Further Bull. Chem. Soc. Japan, 35, 1751-1755 (1962) discloses oxidation of p-xylene with cerium(lV) sulfate to prepare p-tolualdehyde, and electrolytic oxidation of cerium(lll) sulfate for repeated use. However, nothing is reported about p-tert-butyl toluene. The disclosed processes have the drawbacks of being low in current efficiency and in conversion to the desired product and involving a further reduction in conversion or yield as the cerium salt is used repeatedly.
We have found that the optimum reaction conditions for the oxidation of compounds with a cerium salt differ delicately with the kind of the starting material to be oxidized.
An object of this invention is to provide a process for oxidizing p-tert-butyl toluene in a very short period of time to obtain p-tert-butyl benzaldehyde in a high yield and a high conversion.
Another object of the invention is to provide a process for preparing p-tert-butyl benzaldehyde with the use of an oxidizing agent which can be regenerated easily, semipermanently and quantitatively for repeated use.
Another object of the invention is to provide a process for preparing p-tert-butyl benzaldehyde with the use of clean electric energy without giving by-products which are likely to cause pollution.
These and other objects of the invention will become apparent from the following description.
The present invention provides a process for preparing p-tert-butyl benzaldehyde characterized by performing at least once the steps of (a) electrolyzing cerium(lll) nitrate or ammonium cerium(lll) nitrate with use of a cathode chamber having contained therein nitrate ion-containing water or a nitrate ion-containing mixture of water and lower fatty acid and an anode chamber having contained therein a mixture of water and lower fatty acid containing the cerium salt to obtain a cerium(lV) nitrate-or ammonium cerium(lV) nitrate-containing mixture of water and the lower fatty acid, and (b) oxidizing p-tert-butyl toluene with the resulting mixture to obtain p-tert-butyl benzaldehyde.
With the process of this invention, the. desired product can be prepared in high yields and high conversions within a very short period of time from a material which is easily available at a low cost, using an oxidizing agent which can be regenerated semipermanently and quantitatively for repeated use. The process utilizes clean electric energy and does not entail formation of by-products that would cause pollution.
The electrolytic oxidation of this invention is conducted in the following manner. A solution mixture of water and a lower fatty acid is placed into an anode chamber which mixture contains cerium (III) nitrate or ammonium cerium(lll) nitrate obtained from an oxidation reaction mixture by separating p-tert-butyl benzaldehyde from the reaction mixture. It is useful to add a small amount of nitric acid or ammonium nitrate to the solution mixture. Water containing nitrate ions, or a nitrate ion-containing solution mixture of water and a lower fatty acid is placed into a cathode chamber. Various compounds are usable as nitrate ion sources, such as nitric acid, ammonium nitrate, sodium nitrate, potassium nitrate, alkyl ammonium salts of nitric acid, etc., among which nitric acid and ammonium nitrate are preferable.Examples of preferred lower fatty acids are those having 1 to 3 carbon atoms, such as formic acid, acetic acid, propionic acid, etc. These acids are usable singly or in admixture.
The electrolytic oxidation of this invention is conducted in the above two chambers, which may be used without any diaphragm. However, the chambers are preferably separated by a porcelain diaphragm, ion exchange diaphragm or the like. The electrolytic oxidation quantitatively affords a solution mixture of water and the lower fatty acid which mixture contains cerium(lV) nitrate or ammonium cerium(lV) nitrate. The current density for the electrolysis is not particularly limited and is determined as desired in accordance with the size of the electrolytic cell, reaction time, etc. The electrodes can be of any known material, such as platinum, iron, stainless steel, carbon, titanium oxide, lead oxide, lead dioxide or the like.The electrolytic reaction, which can be conducted at a temperature of about 0 to about 100 C, may preferably be conducted at about 10 to about 600 C.
When the cerium(lV) nitrate- or ammonium cerium(lV) nitrate-containing solution mixture of water and lower fatty acid is admixed with p-tert-butyl toluene with stirring, an oxidation reaction takes place rapidly, giving p-tert-butyl benzaldehyde in a high yield. The reaction temperature, which is not particularly limited, is preferably about 50 to about 1 200C, more preferably about 60 to about 1 OO"C, when it is desired to complete the reaction within a short period of time.The solution mixture of water and lower fatty acid containing cerium(lV) nitrate or ammonium cerium(lV) nitrate and serving as the oxidizing agent for the oxidation reaction should contain the lower fatty acid in an amount of about 20 to about 90% by weight, preferably about 30 to about 80% by weight, based on the combined amount of the water and lower fatty acid in view of the ability of the mixture to oxidize p-tert-butyl toluene, yield of the desired product, separation of the product, solubility of the cerium salt, starting compound and product, stability of the cerium(lll) salt during electrolytic oxidation, conversion of the salt to the cerium(lV) salt, etc.With about 20 to about 90% by weight of the lower fatty acid present, the cerium(lV) salt acts effectively to oxidize p-tert-butyl toluene, and the desired product, namely p-tertbutyl benzaldehyde, can be separated efficiently. Moreover the cerium(lV) salt is then highly soluble, while the cerium(lll) salt resulting from the oxidation reaction also has good solubility. The reaction product, namely p-tert-butyl benzaldehyde, can be separated from the reaction mixture by a known method. For example, the product can be easily separated by extraction with the use of a solvent, such as ether, ester, aromatic hydrocarbon, aliphatic hydrocarbon, hydrocarbon halide or the like.
The mixture of water and lower fatty acid separated from p-tert-butyl benzaldehyde and containing cerium(lll) nitrate or ammonium cerium(lll) nitrate is subjected to the electrolytic oxidation reaction already described to produce cerium(lV) salt by regeneration.
According to the invention, the electrolytic oxidation step and the p-tert-butyl toluene oxidation step are conducted at least once to afford p-tert-butyl benzaldehyde in a high yield. The invention has the outstanding advantage that even when these steps are repeated a large number of times, the desired product can be produced in a high yield of at least about 95% each time.
The invention will be further described with reference to the following examples and comparison example.
Example 1
Into a reactor equipped with a condenser are placed 200 mg of p-tert-butyl toluene and 3.70 g of ammonium cerium(lV) nitrate, and 10 ml of 50% by weight aqueous solution of acetic acid is further placed into the reactor. The mixture is then vigorously stirred for 30 minutes with the reactor placed in an oil bath at 70 to 100 C. The reaction mixture is subjected to extraction with n-hexane, and the extract is washed with an aqueous solution of sodium bicarbonate and with an aqueous solution of sodium chloride and dried over anhydrous sodium sulfate. Removal of the solvent from the dry extract affords 211 mg of p-tert-butyl benzaldehyde (purity 99%). Yield: 96.5%.
The mixture of water and acetic acid containing ammonium cerium(lll) nitrate and separated from the extract is placed into an anode chamber separated from a cathode chamber by a porcelain diaphragm. A solution of 200 mg of ammonium nitrate in 20 ml of 50% by weight aqueous solution of acetic acid is placed into the cathode chamber. With platinum electrodes installed in the anode and cathode chambers, the cerium salt is electrolyzed with a constant current of 70 mA to pass electricity across the electrodes in a quantity of 1.2 F/mole. The solution in the anode chamber is withdrawn therefrom after the completion of electrolysis and then reacted with 200 mg of p-tert-butyl toluene.
The same procedure as above is thereafter repeated to give 210.0 mg of p-tert-butyl benzaldehyde.
Yield: 96.0%.
Examples 2-10 The oxidation of p-tert-butyl toluene and electrolytic oxidation of ammonium cerium(lll) nitrate are repeatedly conducted substantially in the same manner as in Example 1 under the conditions listed in Table 1, which also shows the results.
Table 1
Oxidation of
Electrolytic reaction p-tert-butyl
- toluene
Electrodes Quantity of Ammonium
Current electricity sulfate Temp. Time Yield
Example (+) { mA) (F/mole) (mug) ( C) (her) (o/O) 2 Pt Pt 70 1.2 200 85-95 0.5 96.0
3 Pt Pt 70 1.2 200 90-95 0.5 96.7
4 Pt Pt 70 1.1 200 75-85 0.5 95.8
5 Pt Pt 70 1.1 200 85-95 0.5 97.0
6 Pt Pt 70 1.1 200 65-75 0.5 96.6
7 Pt Pt 70 1.0 200 50-60 0.5 95.4
8 Pt Pt 70 1.0 200 85-95 0.5 95.6
9 Pt Pt 70 1.0 200 85-95 0.5 96.1
10 Pt Pt 70 1.0 200 85-95 0.5 96.4
Examples 11-18 The process of Example 1 is repeated under the conditions listed in Table 2 below, using carbon or lead oxide for the anode and stainless steel (SUS) for the cathode. The results are shown in Table 2.
Table 2
Oxidation of
Electrolytic reaction p-tert-butyl
toluene
Electrodes Quantity of Ammonium
----- Current electricity sulfate Temp. Time Yield Example r mA) (mA) FF/mole) (mg) (0C) (hr) (%) 85-95 0.5 97.0
11 C SUS 70 1.2 200 85-95 0.5 96.7
12 C SUS 70 1.2 200 65-75 0.5 95.8
13 C SUS 70 1.1 200 85-95 0.5 97.1
14 C SUS 70 1.1 200 85-95 0.5 96.3
15 C SUS 70 1.0 200 85-95 0.5 96.5
16 C SUS 70 1.0 200 55-65 0.5 95.7
17 PbO2 SUS 70 1.2 200 85-95 0.5 95.6
18 PbO2 SUS 70 1.0 200 85-95 0.5 95.9
Example 19
The same procedure as in Example 1 is repeated with a 3% by weight aqueous solution of nitric acid used in the cathode chamber for electrolysis, affording p-tert-butyl benzaldehyde in a yield of 96.2%.
Example 20
A solution of 2.46 9 of cerium(lll) nitrate in a 65% by weight aqueous solution of acetic acid is placed into an anode chamber. A 20 ml quantity of a 65% by weight aqueous solution of acetic acid containing 200 mg of ammonium nitrate dissolved therein is placed into a cathode chamber. The cerium salt is electrolyzed with a constant current of 50 mA to pass electricity across the electrodes in a quantity of 1.2 F/mole. The solution withdrawn from the anode chamber after the completion of electrolysis is reacted with 200 mg of p-tert-butyl toluene in the same manner as in Example 1, giving p-tert-butyl benzaldehyde in a yield of 95.9%.
Example 21
Into a reactor equipped with a condenser are placed 200 mg of p-tert-butyl toluene, 3.70 9 of ammonium cerium(lV) nitrate and 10 ml of 30% by weight aqueous solution of acetic acid. The mixture is then vigorously stirred for 30 minutes with the reactor placed in an oil bath at 70 to 100 C.
The reaction mixture is subjected to extraction with benzene, and the extract is washed with an aqueous solution of sodium bicarbonate and with an aqueous solution of sodium chloride and dried over anhydrous sodium sulfate. Removal of the solvent from the dry extract affords p-tert-butyl benzaldehyde in a yield of 94.7%.
The mixture of water and acetic acid containing ammonium cerium(lll) nitrate and separated from the extract is placed into an anode chamber partitioned from a cathode chamber by an ion exchange diaphragm. A 30% aqueous solution of acetic acid containing 200 mg of ammonium nitrate is placed into the cathode chamber. With use of platinum electrodes, the cerium salt is electrolyzed at 1 50C with a constant current of 50 mA to pass electricity across the electrodes in a quantity of 1.1 F/mole. After the completion of electrolysis, p-tert-butyl toluene is treated with the solution in the anode chamber in the same manner as above to give p-tert-butyl benzaldehyde in a yield of 95.1%.
Comparison Example 1
Into a reactor are placed 2.0 g of p-tert-butyl toluene and 3.70 g of ammonium cerium(lV) nitrate, and 100 ml of water is further placed into the reactor. The mixture is vigorously stirred at 70 to 1 000C for 30 minutes. The reaction mixture is subjected to extraction with n-hexane, and the extract is washed with an aqueous solution of sodium bicarbonate and with an aqueous solution of sodium chloride and dried over anhydrous sodium sulfate. When the dry extract is distilled after the removal of the solvent therefrom, the starting material only is recovered, and no p-tert butyl benzaldehyde is obtained.
Claims (12)
1. A process for preparing p-tert-butyl benzaldehyde characterized by performing at least once the steps of (a) electrolyzing cerium(lll) nitrate or ammonium cerium(lll) nitrate with use of a cathode chamber having contained therein nitrate ion-containing water or a nitrate ion-containing mixture of water and lower fatty acid and an anode chamber having contained therein a mixture of water and lower fatty acid containing the cerium salt to obtain a cerium(lV) nitrate- or ammonium cerium(lV)nitrate-containing mixture of water and the fatty acid, and (b) oxidizing p-tert-butyl toluene with the resulting mixture to obtain p-tert-butyl benzaldehyde.
2. A process as defined in claim 1 wherein the source of the nitrate ion is nitric acid, ammonium nitrate, sodium nitrate, potassium nitrate or an alkyl ammonium salt of nitric acid.
3. A process as defined in claim 2 wherein the nitrate ion source is nitric acid or ammonium nitrate.
4. A process as defined in claim 1 wherein the lower fatty acid is formic acid, acetic acid or propionic acid.
5. A process as defined in claim 1 wherein the mixture of water and lower fatty acid containing the cerium salt to be electrolyzed further contains nitric acid or ammonium nitrate admixed therewith.
6. A process as defined in claim 1 wherein the mixture resulting from the step (a) contains about 20 to about 90% by weight of the fatty acid based on the combined amount of the water and the fatty acid in the mixture.
7. A process as defined in claim 6 wherein the proportion of the fatty acid in the resulting mixture is about 30 to about 80% by weight.
8. A process as defined in claim 1 wherein the cathode chamber is partitioned from the anode chamber by a diaphragm.
9. A process as defined in claim 1 wherein the p-tert-butyl toluene is oxidized at about 50 to about 1200C.
10. A process as defined in claim 9 wherein the oxidation reaction is conducted at about 60 to about 1000C.
11. A process as defined in claim 1 wherein the cerium salt is electrolyzed at about 0 to about 1000C.
12. A process as defined in claim 11 wherein the electrolysis is conducted at about 10 to about 600 C.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP9747879A JPS5620537A (en) | 1979-07-30 | 1979-07-30 | Preparation of p-tertiary-butylbenzaldehyde |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| GB2060612A true GB2060612A (en) | 1981-05-07 |
| GB2060612B GB2060612B (en) | 1983-09-21 |
Family
ID=14193390
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB8024137A Expired GB2060612B (en) | 1979-07-30 | 1980-07-23 | Process for preparing p-tert-butyl benzaldehyde |
Country Status (5)
| Country | Link |
|---|---|
| JP (1) | JPS5620537A (en) |
| CH (1) | CH644575A5 (en) |
| DE (1) | DE3028757C2 (en) |
| FR (1) | FR2462411A1 (en) |
| GB (1) | GB2060612B (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS58502027A (en) * | 1981-11-23 | 1983-11-24 | バロ−ス・コ−ポレ−ション | Peripherals adapted to monitor low data rate serial input/output interfaces |
| JPH0690480B2 (en) * | 1986-12-08 | 1994-11-14 | コニカ株式会社 | Silver halide photographic light-sensitive material with excellent color mixing prevention effect |
| GB9319945D0 (en) * | 1993-09-28 | 1993-11-17 | Solvay Interox Ltd | Oxidation of alkylaromatic compounds |
| CN106319553A (en) * | 2015-07-02 | 2017-01-11 | 中国科学院大连化学物理研究所 | Method for obtaining Ce(IV) by conducting photoelectric catalysis oxidation on Ce(III), Ce(IV) and application |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3346622A (en) * | 1965-07-15 | 1967-10-10 | Gulf Research Development Co | Preparation of an aromatic ester from an alkyl-aromatic compound and a carboxylic acid in the presence of a tetravalent cerium salt and an inhibitor |
| GB1203434A (en) * | 1967-10-23 | 1970-08-26 | Ici Ltd | Oxidation of organic materials |
-
1979
- 1979-07-30 JP JP9747879A patent/JPS5620537A/en active Granted
-
1980
- 1980-07-23 GB GB8024137A patent/GB2060612B/en not_active Expired
- 1980-07-29 DE DE3028757A patent/DE3028757C2/en not_active Expired
- 1980-07-30 FR FR8016779A patent/FR2462411A1/en active Granted
- 1980-07-30 CH CH581280A patent/CH644575A5/en not_active IP Right Cessation
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5620537A (en) | 1981-02-26 |
| JPS6157818B2 (en) | 1986-12-09 |
| FR2462411B1 (en) | 1984-11-02 |
| DE3028757C2 (en) | 1982-09-16 |
| GB2060612B (en) | 1983-09-21 |
| CH644575A5 (en) | 1984-08-15 |
| FR2462411A1 (en) | 1981-02-13 |
| DE3028757A1 (en) | 1981-02-05 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PCNP | Patent ceased through non-payment of renewal fee |
Effective date: 19990723 |