EP0012942A2 - Electrolytic process for producing benzaldehydes - Google Patents
Electrolytic process for producing benzaldehydes Download PDFInfo
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- EP0012942A2 EP0012942A2 EP79105128A EP79105128A EP0012942A2 EP 0012942 A2 EP0012942 A2 EP 0012942A2 EP 79105128 A EP79105128 A EP 79105128A EP 79105128 A EP79105128 A EP 79105128A EP 0012942 A2 EP0012942 A2 EP 0012942A2
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- 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
Definitions
- the invention relates to a method for the electrochemical production of benzaldehydes.
- R 1 represents a hydrogen atom, an alkyl radical or an aryl radical
- R 2 represents a hydrogen atom or an.alkyl group with 1 to 6 C atoms
- R 3 represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms
- Suitable alkyl radicals R 1 , R 2 and R 3 are those having 1 to 6, preferably 1 to 4, carbon atoms. Phenyl radicals which can be substituted by alkyl, halogen, alkoxy and / or acyloxy groups may be mentioned as aryl radicals R 1 .
- Starting materials of formula II are thus methylbenzenes, benzyl alcohols or the alkanoic acid esters of benzyl alcohols which are not substituted in the 4-position or contain the radical R 1 mentioned , such as toluene, p-xylene, p-tert-butyl-toluene, p-phenyltoluene , Benzyl alcohol, p-methylbenzyl alcohol, p-tert-butylbenzyl alcohol, benzyl acetate, p-methylbenzyl acetate and p-tert-butylbenzyl acetate.
- Preferred alkanoic acids of formula III are formic acid, acetic acid and propionic acid.
- a mixture of the benzene derivative of the formula II, water and the alkanoic acid of the formula III is used as the electrolyte, which may additionally contain a conductive salt to improve the conductivity.
- the usual salts in organic electrochemistry can be used as the conductive salts, which are soluble in the solution to be electrolyzed and largely stable under the test conditions.
- Fluoride such as NaF and KF, tetrafluoroborate such as NaBF 4 and Et 4 NBF 4 , perchlorate such as NaClO 4 and Et 4 ClO 4 and sulfate such as Et 4 NSO 4 Et are particularly advantageous as conductive salts.
- the composition of the electrolyte can be chosen within wide limits.
- the solutions used in electrolysis have the following composition, for example:
- the electrode materials used in the process according to the invention will be those which are stable under the conditions of the electrolysis.
- Suitable anode materials are, for example, graphite, noble metals such as platinum and noble metal coated titanium electrodes.
- graphite, iron, steel, lead or precious metal electrodes are used as cathodes.
- Current density and turnover can also be selected within wide limits. The current density is, for example, 1 to 10 A / dm 2 .
- the electrolysis itself is, for example. with 2 to 12, preferably 4 to 12 F / mol of starting compound and at temperatures below 100 ° C, advantageously between 10 and 90 ° C.
- the method according to the invention can be carried out both in divided and in undivided electrolysis cells.
- the electrolysis discharges are generally worked up by distillation. Alkanoic acid, water and any starting materials still present are separated from the benzaldehydes by distillation and can be returned to the electrolysis.
- the conductive salts used can then be separated from the aldehydes, for example by filtration, and can also be used again in the electrolysis.
- the benzaldehydes can be further purified, for example, by rectification.
- the carboxylic acid esters of the corresponding benzyl alcohols obtained as by-products in the process according to the invention can be returned to the electrolysis. However, they can also be isolated before this recycling and saponified to the corresponding benzyl alcohols by processes known per se, for example by acidic transesterification with CH 3 OH / H 2 SO 4 .
- benzaldehydes obtainable by the process according to the invention are valuable intermediates for active substances and fragrances.
- 4-tert-butylbenzaldehyde finds e.g. Use as a preliminary product for fungicides and serves as a starting material for the fragrance Lilial.
- the electrolyte is pumped through a heat exchanger during the electrolysis.
- the electrolyte is pumped through a heat exchanger during the electrolysis.
- the electrolyte is pumped through a heat exchanger during the electrolysis.
- the electrolyte is pumped through a heat exchanger during the electrolysis.
- the electrolyte is pumped through a heat exchanger during the electrolysis.
- the electrolyte is pumped through a heat exchanger during the electrolysis.
- the electrolyte is pumped through a heat exchanger during the electrolysis.
- the electrolyte is pumped through a heat exchanger during the electrolysis.
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- Chemical Kinetics & Catalysis (AREA)
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Abstract
Verfahren zur Herstellung von Benzaldehyden der allgemeinen Formel <IMAGE> in der R' ein Wasserstoffatom, einen Alkylrest oder einen Arylrest bedeutet, bei dem man eine Verbindung der Formel <IMAGE> in der X für ein Wasserstoffatom, eine Hydroxylgruppe oder eine R²-COO-Gruppe steht, und R² ein Wasserstoffatom oder eine Alkylgruppe mit 1 bis 6 C-Atomen bedeutet, in Gegenwart von Wasser und einer Alkansäure der Formel R³COOH III, in der R³ ein Wasserstoffatom oder eine Alkylgruppe mit 1 bis 6 C-Atomen bedeutet, elektrochemisch oxidiert.Process for the preparation of benzaldehydes of the general formula <IMAGE> in which R 'is a hydrogen atom, an alkyl radical or an aryl radical, in which a compound of the formula <IMAGE> in which X is a hydrogen atom, a hydroxyl group or an R²-COO Group, and R² represents a hydrogen atom or an alkyl group having 1 to 6 C atoms, in the presence of water and an alkanoic acid of the formula R³COOH III, in which R³ represents a hydrogen atom or an alkyl group having 1 to 6 C atoms, electrochemically oxidized .
Description
Die Erfindung betrifft ein Verfahren zur elektrochemischen Herstellung von Benzaldehyden.The invention relates to a method for the electrochemical production of benzaldehydes.
Die Elektrosynthese von in 4-Stellung.substituierten Benzaldehyden durch anodische Oxidation der entsprechenden Alkylbenzole wird z.B. in Helv. Chem. Acta 9, 1097 (1926) beschrieben. Bei diesem bekannten Verfahren, bei dem man die Alkylbenzole in schwefelsaurer Lösung elektrolysiert, werden die Benzaldehyde nur in geringer Ausbeute erhalten. Außerdem bereitet die Isolierung der Aldehyde aus dem bei der Elektrolyse entstehenden Vielkomponentengemisch so große Schwierigkeiten, daß sich diese Synthese in der Technik nicht realisieren ließ.The electrosynthesis of benzaldehydes substituted in the 4-position by anodic oxidation of the corresponding alkylbenzenes is e.g. in Helv. Chem. Acta 9, 1097 (1926). In this known process, in which the alkylbenzenes are electrolyzed in sulfuric acid solution, the benzaldehydes are obtained only in low yield. In addition, the isolation of the aldehydes from the multicomponent mixture resulting from the electrolysis is so difficult that this synthesis could not be achieved in industry.
Es wurde nun gefunden, daß man Benzaldehyde der allgemeinen Formel.
Als Alkylreste R1, R2 und R3 kommen solche mit 1 bis 6, vorzugsweise 1.bis 4 C-Atomen in Betracht. Als Arylreste R1 seien Phenylreste, die durch Alkyl-, Halogen-, Alkoxy-und/oder Acyloxygruppen substituiert sein können, genannt. Ausgangsstoffe der Formel II sind somit Methylbenzole, Benzylalkohole oder die Alkansäureester der Benzylalkohole, die in 4-Stellung nicht substituiert sind oder den genannten Rest R1 enthalten, wie Toluol, p-Xylol, p-tert.-Butyl- toluol, p-Phenyltoluol, Benzylalkohol, p-Methylbenzylalkohol, p-tert.-Butylbenzylalkohol, Benzylacetät, p-Methylbenzylacetat und p-tert.-Butylbenzylacetat. Von diesen Ausgangsstoffen sind p-Xylol, p-tert.-Butyltoluol, p-Methylbenzylalkohol, p-tert.-Butylbenzylalkohol, p-Methylbenzylacetat und p-tert.-Butylbenzylacetat von besonderem technischem Interesse.Suitable alkyl radicals R 1 , R 2 and R 3 are those having 1 to 6, preferably 1 to 4, carbon atoms. Phenyl radicals which can be substituted by alkyl, halogen, alkoxy and / or acyloxy groups may be mentioned as aryl radicals R 1 . Starting materials of formula II are thus methylbenzenes, benzyl alcohols or the alkanoic acid esters of benzyl alcohols which are not substituted in the 4-position or contain the radical R 1 mentioned , such as toluene, p-xylene, p-tert-butyl-toluene, p-phenyltoluene , Benzyl alcohol, p-methylbenzyl alcohol, p-tert-butylbenzyl alcohol, benzyl acetate, p-methylbenzyl acetate and p-tert-butylbenzyl acetate. Of these starting materials, p-xylene, p-tert-butyltoluene, p-methylbenzyl alcohol, p-tert-butylbenzyl alcohol, p-methylbenzyl acetate and p-tert.-butylbenzyl acetate are of particular technical interest.
Als Alkansäuren der Formel III sind Ameisensäure, Essigsäure und Propionsäure bevorzugt.Preferred alkanoic acids of formula III are formic acid, acetic acid and propionic acid.
Als Elektrolyt wird ein Gemisch aus dem Benzolderivat der Formel II, Wasser und der Alkansäure der Formel III verwendet, das zur Verbesserung der Leitfähigkeit zusätzlich ein Leitsalz enthalten känn. Als Leitsalze können dabei die in der organischen Elektrochemie üblichen Salze eingesetzt werden, die in der zu elektrolysierenden Lösung löslich und unter den Versuchsbedingungen weitgehend stabil sind. Besonders vorteilhaft als Leitsalze sind Fluoride wie NaF und KF, Tetrafluoroborate wie NaBF4 und Et4NBF4, Perchlorate wie NaClO4 und Et4ClO4 und Sulfate wie Et4NSO4Et. Die Zusammensetzung des Elektrolyten kann in weiten Grenzen gewählt werden. Die in die Elektrolyse eingesetzten Lösungen haben beispielsweise folgende Zusammen- settung:A mixture of the benzene derivative of the formula II, water and the alkanoic acid of the formula III is used as the electrolyte, which may additionally contain a conductive salt to improve the conductivity. The usual salts in organic electrochemistry can be used as the conductive salts, which are soluble in the solution to be electrolyzed and largely stable under the test conditions. Fluoride such as NaF and KF, tetrafluoroborate such as NaBF 4 and Et 4 NBF 4 , perchlorate such as NaClO 4 and Et 4 ClO 4 and sulfate such as Et 4 NSO 4 Et are particularly advantageous as conductive salts. The composition of the electrolyte can be chosen within wide limits. The solutions used in electrolysis have the following composition, for example:
Die Elektrolyseausträge werden in der Regel destillativ aufgearbeitet. Alkansäure, Wasser und evtl. noch vorhandene Ausgangsmaterialien werden von den Benzaldehyden durch Destillation abgetrennt und können zur Elektrolyse zurückgeführt werden. Die verwendeten Leitsalze lassen sich dann von den Aldehyden beispielsweise durch Filtration abtrennen und können ebenfalls wieder in die Elektrolyse eingesetzt werden. Die Benzaldehyde lassen sich z.B. durch Rektifikation weiter reinigen. Die bei dem erfindungsgemäßen Verfahren als Nebenprodukte anfallenden Carbonsäureester der entsprechenden Benzylalkohole können in die Elektrolyse zurückgeführt werden. Man kann sie aber auch vor dieser Rückführung isolieren und nach an sich bekannten Verfahren, z.B. durch saure Umesterung mit CH3OH/H2SO4, zu den entsprechenden Benzylalkoholen verseifen.The electrolysis discharges are generally worked up by distillation. Alkanoic acid, water and any starting materials still present are separated from the benzaldehydes by distillation and can be returned to the electrolysis. The conductive salts used can then be separated from the aldehydes, for example by filtration, and can also be used again in the electrolysis. The benzaldehydes can be further purified, for example, by rectification. The carboxylic acid esters of the corresponding benzyl alcohols obtained as by-products in the process according to the invention can be returned to the electrolysis. However, they can also be isolated before this recycling and saponified to the corresponding benzyl alcohols by processes known per se, for example by acidic transesterification with CH 3 OH / H 2 SO 4 .
Die nach dem erfindungsgemäßen Verfahren erhältlichen Benzaldehyde sind wertvolle Zwischenprodukte für Wirkstoffe und Riechstoffe. So findet 4-tert.-Butylbenzaldehyd z.B. Verwendung als Vorprodukt für Fungizide und dient als Ausgangsmaterial für den Riechstoff Lilial.The benzaldehydes obtainable by the process according to the invention are valuable intermediates for active substances and fragrances. For example, 4-tert-butylbenzaldehyde finds e.g. Use as a preliminary product for fungicides and serves as a starting material for the fragrance Lilial.
Das erfindungsgemäße Verfahren wird an folgenden Beispielen weiter verdeutlicht.The process according to the invention is further illustrated in the following examples.
Anodische Oxidation von p-tert.-ButyltoluolAnodic oxidation of p-tert-butyltoluene
Der Elektrolyt wird während der Elektrolyse über einen Wärmeaustauscher umgepumpt.The electrolyte is pumped through a heat exchanger during the electrolysis.
Nach Beendigung der Elektrolyse werden Essigsäure und Was ser bei Normaldruck abdestilliert, NaBF4 (57 g) abfiltrie und der Rückstand bei 20 bis 2 Torr und 30 bis 100°C fraktioniert destilliert. Hierbei erhält man neben 6,2 g unumgesetztem p-tert.-Butyltoluol 133,5 g p-tert.-Butyl- benzaldehyd und 141,1 g p-tert.-Butylbenzylacetat. Dies entspricht einer Materialausbeute von.77 % und einer Stromausbeute von 58,4 %. Zur Isolierung des p-tert.-But benzaldehyds wird das Gemisch bei 20 bis 30 Torr und einer Sumpftemperatur von 150 bis 170°C rektifiziert. Das dabei als Sumpfprodukt anfallende p-tert.-Butylbenzylacetat kann erneut der Elektrolyse zugeführt werden.After the electrolysis has ended, acetic acid and water are distilled off at atmospheric pressure, NaBF 4 (57 g) is filtered off and the residue is fractionally distilled at 20 to 2 torr and 30 to 100 ° C. In addition to 6.2 g of unreacted p-tert-butyltoluene, 133.5 g of p-tert-butylbenzaldehyde and 141.1 g of p-tert-butylbenzyl acetate are obtained. This corresponds to a material yield of 77% and an electricity yield of 58.4%. To isolate the p-tert-but benzaldehyde, the mixture is rectified at 20 to 30 torr and a bottom temperature of 150 to 170 ° C. The p-tert-butylbenzyl acetate obtained as the bottom product can be returned to the electrolysis.
Man verfährt, wie in Beispiel 1 beschrieben, wobei man die Elektrolyse von p-tert.-Butyltoluol jedoch mit 6,5 F/Mol ausführt. Es werden hierbei neben 22 g p-tert.--Butylbenzylacetat 198 g p-tert.-Butylbenzaldehyd erhalten. Dies entspricht einer Ausbeute von 66,5 %.The procedure is as described in Example 1, but the electrolysis of p-tert-butyltoluene is carried out at 6.5 F / mol. In addition to 22 g of p-tert-butylbenzyl acetate, 198 g of p-tert-butylbenzaldehyde are obtained. This corresponds to a yield of 66.5%.
Anodische Oxidation von p-tert.-ButyltoluolAnodic oxidation of p-tert-butyltoluene
Der Elektrolyt wird während der Elektrolyse über einen Wärmeaustauscher umgepumpt.The electrolyte is pumped through a heat exchanger during the electrolysis.
Arbeitet man den Elektrolyseaustrag analog Beispiel 1 auf, so erhält man neben 13,2 g unumgesetztem p-tert.-Butyl- toluol 120,3 g p-tert.-Butylbenzaldehyd und 144,1 g p-tert.-Butylbenzylacetat. Dies entspricht einer Materiallaus beute von 75,5 % und einer Stromausbeute von 51,4 %.If the electrolysis discharge is worked up analogously to Example 1, 120.3 g of p-tert-butylbenzaldehyde and 144.1 g of p-tert-butylbenzyl acetate are obtained in addition to 13.2 g of unreacted p-tert-butyl-toluene. This corresponds to a material loot of 75.5% and an electricity yield of 51.4%.
Anodische Oxidation von p-tert.-ButyltoluolAnodic oxidation of p-tert-butyltoluene
Der Elektrolyt wird während der Elektrolyse über einen Wärmeaustauscher umgepumpt.The electrolyte is pumped through a heat exchanger during the electrolysis.
Arbeitet man den Elektrolyseaustrag analog Beispiel 1 auf, so erhält man neben 25,2 g unumgesetztem p-tert.-Butyl- toluol 284,8 g p-tert.-Butylbenzaldehyd und 295,3 g p-tert.-Butylbenzylacetat. Dies entspricht einer Materialausbeute von 83,3 % und einer Stromausbeute von 58,2 %. Man trennt den p-tert.-Butylbenzaldehyd wie in Beispiel 1 beschrieben vom p-tert.-Butylbenzylacetat ab.If the electrolysis discharge is worked up analogously to Example 1, 284.8 g of p-tert-butylbenzaldehyde and 295.3 g of p-tert-butylbenzyl acetate are obtained in addition to 25.2 g of unreacted p-tert-butyl-toluene. This corresponds to a material yield of 83.3% and an electricity yield of 58.2%. The p-tert-butylbenzaldehyde is separated from the p-tert-butylbenzyl acetate as described in Example 1.
90 g des als Nebenprodukt isolierten p-tert.-Butylbenzyl- acetates werden mit 96 g Methanol und 1 g konzentrierter Schwefelsäure gemischt und unter Rühren drei Stunden Rückfluß gekocht. Nach Abkühlen wird die Lösung mit NaOH neutralisiert. Methanol und Methylacetat werden bei Normaldruck abdestilliert und der Rückstand bei 0,1 Torr und 68 bis 70°C fraktioniert destilliert. Hierbei erhält man 65 g p-tert.-Butylbenzylalkohol (entsprechend einer Ausbeute von 90,7 %), die z.B. nach Beispiel 5 für die Herstellung von p-tert.-Butylberizaldehyd herangezogen werden können.90 g of the p-tert-butylbenzyl acetate isolated as a by-product are mixed with 96 g of methanol and 1 g of concentrated sulfuric acid and refluxed for three hours with stirring. After cooling, the solution is neutralized with NaOH. Methanol and methyl acetate are distilled off under normal pressure and the residue is fractionally distilled at 0.1 Torr and 68 to 70 ° C. This gives 65 g of p-tert-butylbenzyl alcohol (corresponding to a yield of 90.7%), for example according to Example 5 for the Production of p-tert-butylberizaldehyde can be used.
Anodische Oxidation von p-tert.-ButylbenzylalkoholAnodic oxidation of p-tert-butylbenzyl alcohol
Der Elektrolyt wird während der Elektrolyse über einen Wärmeaustauscher umgepumpt.The electrolyte is pumped through a heat exchanger during the electrolysis.
Nach Beendigung der Elektrolyse werden Essigsäure und Wasser bei Normaldruck abdestilliert, NaBF4 (55 g) abfiltriert und der Rückstand bei 2 bis 3 Torr und 77 bis 100°C fraktioniert destilliert. Hierbei erhält man 4,9 g p-tert.--Butylbenzylalkohol, 166,9 g p-tert.-Butylbenzaldehyd und 70,4 g p-tert.-Butylbenzylacetat. Dies entspricht einer Materialausbeute von 73,7 % und einer Stromausbeute von 58,3 %.After the electrolysis has ended, acetic acid and water are distilled off at atmospheric pressure, NaBF 4 (55 g) is filtered off and the residue is fractionally distilled at 2 to 3 torr and 77 to 100 ° C. This gives 4.9 g of p-tert-butylbenzyl alcohol, 166.9 g of p-tert-butylbenzaldehyde and 70.4 g of p-tert-butylbenzyl acetate. This corresponds to a material yield of 73.7% and an electricity yield of 58.3%.
Anodische Oxidation von p-tert.-Eutylbenzylacetat
Elektrolyse mit 2 F/Mol p-tert.-ButylbenzylacetatElectrolysis with 2 F / mol p-tert-butylbenzyl acetate
Der Elektrolyt wird während der Elektrolyse über einen Wärmeaustauscher umgepumpt.The electrolyte is pumped through a heat exchanger during the electrolysis.
Nach Beendigung der Elektrolyse werden Essigsäure und Wasser bei Normaldruck abdestilliert NaBF4 (55 g) abfiltriert und der Rückstand bei 1 bis 5 Torr und 35 bis 110°C fraktioniert destilliert. Hierbei erhält man neben 139,6 g unumgesetzten p-tert.-Butylbenzylacetat 105,7 g p-tert.-Butylbenzaldehyd. Dies entspricht einer Materialausbeute von 79,4 % und einer Stromausbeute von 43,5 %.After the electrolysis has ended, acetic acid and water are distilled off at atmospheric pressure and NaBF 4 (55 g) is filtered off and the residue is fractionally distilled at 1 to 5 torr and 35 to 110 ° C. In addition to 139.6 g of unreacted p-tert-butylbenzyl acetate, 105.7 g of p-tert-butylbenzaldehyde are obtained. This corresponds to a material yield of 79.4% and an electricity yield of 43.5%.
Anodische Oxidation von p-XylolAnodic oxidation of p-xylene
Der Elektrolyt wird während der Elektrolyse über einen Wärmeaustauscher umgepumpt.The electrolyte is pumped through a heat exchanger during the electrolysis.
Nach Beendigung der Elektrolyse werden Essigsäure, Wasser und unumgesetztes p-Xylol (24,8 g) bei Normaldruck abdestilliert, NaBF4 (54 g) abfiltriert und der Rückstand bei 30 bis 110°C und 0,7 bis 2 Torr fraktioniert destilliert. Hierbei erhält man 70,4 g p-Methylbenzaldehyd und 70,3 g p-Methylbenzylacetat. Dies entspricht einer Materialausbeute von 62,9 %.After the electrolysis has ended, acetic acid, water and unreacted p-xylene (24.8 g) are distilled off at atmospheric pressure, NaBF 4 (54 g) is filtered off and the residue is fractionally distilled at 30 to 110 ° C. and 0.7 to 2 torr. This gives 70.4 g of p-methylbenzaldehyde and 70.3 g of p-methylbenzyl acetate. This corresponds to a material yield of 62.9%.
Anodische Oxidation von p-XylolAnodic oxidation of p-xylene
Arbeitet man den Elektrolyseaustrag analog Beispiel 7 auf, so erhält man neben 136,2 g unumsesetztem p-Xylol 30 g Methylbenzaldehyd und 40,3 g p-Methylbenzylacetat. Dies entspricht einer Materialausbeute von 69,4If the electrolysis discharge is worked up analogously to Example 7, 30 g of methylbenzaldehyde and 40.3 g of p-methylbenzyl acetate are obtained in addition to 136.2 g of unreacted p-xylene. This corresponds to a material yield of 69.4
Anodische Oxidation von ToluolAnodic oxidation of toluene
Nach Beendigung der Elektrolyse werden Wasser, Essigsäure und unumgesetztes Toluol (43 g) bei Normaldruck abdestilliert, NaBF4 (58 g) abfiltriert und der Rückstand bei 10 bis 30 Torr und 30 bis 100°C fraktioniert destilliert. Hierbei erhält men 81,6 g Benzaldehyd und 31,9 g Benzylacetat. Dies entspricht einer Materialausbeute von 64,6 %.After the electrolysis had ended, water, acetic acid and unreacted toluene (43 g) were distilled off at atmospheric pressure, NaBF 4 (58 g) was filtered off and the residue was fractionally distilled at 10 to 30 torr and 30 to 100 ° C. This gives 81.6 g of benzaldehyde and 31.9 g of benzyl acetate. This corresponds to a material yield of 64.6%.
Claims (8)
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
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DE2855508 | 1978-12-22 | ||
DE19782855508 DE2855508A1 (en) | 1978-12-22 | 1978-12-22 | METHOD FOR PRODUCING BENZALDEHYDES |
Publications (3)
Publication Number | Publication Date |
---|---|
EP0012942A2 true EP0012942A2 (en) | 1980-07-09 |
EP0012942A3 EP0012942A3 (en) | 1980-07-23 |
EP0012942B1 EP0012942B1 (en) | 1982-01-27 |
Family
ID=6058012
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
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EP79105128A Expired EP0012942B1 (en) | 1978-12-22 | 1979-12-13 | Electrolytic process for producing benzaldehydes |
Country Status (5)
Country | Link |
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US (1) | US4235683A (en) |
EP (1) | EP0012942B1 (en) |
JP (1) | JPS5589487A (en) |
DE (2) | DE2855508A1 (en) |
DK (1) | DK149618C (en) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0072914A1 (en) * | 1981-08-19 | 1983-03-02 | BASF Aktiengesellschaft | Process for the production of alkyl-substituted benzaldehydes |
EP0030588B1 (en) * | 1979-11-16 | 1984-04-25 | F. HOFFMANN-LA ROCHE & CO. Aktiengesellschaft | Process for the preparation of p-tert.-butylbenzaldehyde |
EP0231053A1 (en) * | 1986-01-06 | 1987-08-05 | The Dow Chemical Company | Electrocatalytic method for producing quinone methides and dihydroxybenzophenones |
Families Citing this family (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4164233A (en) * | 1978-03-07 | 1979-08-14 | Mcandrew James R | Vehicle covering apparatus |
DE2948455A1 (en) * | 1979-12-01 | 1981-06-11 | Basf Ag, 6700 Ludwigshafen | METHOD FOR PRODUCING 4-TERT. BUTYLBENZALDEHYDE. |
US4387007A (en) * | 1980-11-17 | 1983-06-07 | Hoffmann-La Roche Inc. | Process for the manufacture of an aldehyde |
GB8309571D0 (en) * | 1983-04-08 | 1983-05-11 | Albright & Wilson | Accelerated sealing of anodised aluminium |
DE3913166A1 (en) * | 1989-04-21 | 1990-10-25 | Basf Ag | METHOD FOR PRODUCING BENZALDEHYDDIALKYLACETALS AND NEW BENZALDEHYDDIALKYLACETALS AND BENZYL ESTERS |
KR102307579B1 (en) * | 2019-09-18 | 2021-10-05 | 한국과학기술연구원 | Method for preparing benzaldehyde |
Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
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US4148696A (en) * | 1978-03-20 | 1979-04-10 | Uop Inc. | Electrochemical oxidation of activated alkyl aromatic compounds |
Family Cites Families (1)
Publication number | Priority date | Publication date | Assignee | Title |
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JPS583035B2 (en) * | 1976-04-12 | 1983-01-19 | 株式会社クラレ | Method of oxidizing paraphenoxytoluene |
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1978
- 1978-12-22 DE DE19782855508 patent/DE2855508A1/en not_active Withdrawn
-
1979
- 1979-12-05 US US06/100,654 patent/US4235683A/en not_active Expired - Lifetime
- 1979-12-13 EP EP79105128A patent/EP0012942B1/en not_active Expired
- 1979-12-13 DE DE7979105128T patent/DE2962005D1/en not_active Expired
- 1979-12-19 DK DK543079A patent/DK149618C/en not_active IP Right Cessation
- 1979-12-21 JP JP16580779A patent/JPS5589487A/en active Granted
Patent Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
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US4148696A (en) * | 1978-03-20 | 1979-04-10 | Uop Inc. | Electrochemical oxidation of activated alkyl aromatic compounds |
Non-Patent Citations (1)
Title |
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CHEMICAL ABSTRACTS, Band 19 (1925), Seite 783, C.A. MANN et al.: "Electrochemical oxidation of toluene to benzaldehyde", & Trans.Am.Electrochem.Soc. 47 (preprint), 1925. * |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0030588B1 (en) * | 1979-11-16 | 1984-04-25 | F. HOFFMANN-LA ROCHE & CO. Aktiengesellschaft | Process for the preparation of p-tert.-butylbenzaldehyde |
EP0072914A1 (en) * | 1981-08-19 | 1983-03-02 | BASF Aktiengesellschaft | Process for the production of alkyl-substituted benzaldehydes |
EP0231053A1 (en) * | 1986-01-06 | 1987-08-05 | The Dow Chemical Company | Electrocatalytic method for producing quinone methides and dihydroxybenzophenones |
Also Published As
Publication number | Publication date |
---|---|
DK149618B (en) | 1986-08-11 |
DE2962005D1 (en) | 1982-03-11 |
JPS5589487A (en) | 1980-07-07 |
EP0012942B1 (en) | 1982-01-27 |
EP0012942A3 (en) | 1980-07-23 |
DK149618C (en) | 1987-02-02 |
DE2855508A1 (en) | 1980-07-10 |
DK543079A (en) | 1980-06-23 |
US4235683A (en) | 1980-11-25 |
JPS6350434B2 (en) | 1988-10-07 |
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