DE936871C - Process for the preparation of pyridine aldehydes - Google Patents
Process for the preparation of pyridine aldehydesInfo
- Publication number
- DE936871C DE936871C DER15628A DER0015628A DE936871C DE 936871 C DE936871 C DE 936871C DE R15628 A DER15628 A DE R15628A DE R0015628 A DER0015628 A DE R0015628A DE 936871 C DE936871 C DE 936871C
- Authority
- DE
- Germany
- Prior art keywords
- pyridine
- preparation
- aldehyde
- aldehydes
- pyridine aldehydes
- 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
- JUJWROOIHBZHMG-UHFFFAOYSA-N pyridine Substances C1=CC=NC=C1 JUJWROOIHBZHMG-UHFFFAOYSA-N 0.000 title claims description 19
- UMJSCPRVCHMLSP-UHFFFAOYSA-N pyridine Natural products COC1=CC=CN=C1 UMJSCPRVCHMLSP-UHFFFAOYSA-N 0.000 title claims description 14
- 238000000034 method Methods 0.000 title claims description 12
- -1 pyridine aldehydes Chemical class 0.000 title claims description 9
- 238000002360 preparation method Methods 0.000 title description 5
- 230000003647 oxidation Effects 0.000 claims description 9
- 238000007254 oxidation reaction Methods 0.000 claims description 9
- 239000003054 catalyst Substances 0.000 claims description 8
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims description 7
- 238000006243 chemical reaction Methods 0.000 claims description 7
- UQSXHKLRYXJYBZ-UHFFFAOYSA-N Iron oxide Chemical compound [Fe]=O UQSXHKLRYXJYBZ-UHFFFAOYSA-N 0.000 claims description 6
- 239000001301 oxygen Substances 0.000 claims description 6
- 229910052760 oxygen Inorganic materials 0.000 claims description 6
- QPLDLSVMHZLSFG-UHFFFAOYSA-N Copper oxide Chemical compound [Cu]=O QPLDLSVMHZLSFG-UHFFFAOYSA-N 0.000 claims description 3
- 239000005751 Copper oxide Substances 0.000 claims description 3
- 229910000431 copper oxide Inorganic materials 0.000 claims description 3
- 239000003701 inert diluent Substances 0.000 claims description 3
- 239000000126 substance Substances 0.000 claims description 3
- XVMSFILGAMDHEY-UHFFFAOYSA-N 6-(4-aminophenyl)sulfonylpyridin-3-amine Chemical compound C1=CC(N)=CC=C1S(=O)(=O)C1=CC=C(N)C=N1 XVMSFILGAMDHEY-UHFFFAOYSA-N 0.000 claims 1
- 238000006471 dimerization reaction Methods 0.000 claims 1
- CSDSSGBPEUDDEE-UHFFFAOYSA-N 2-formylpyridine Chemical compound O=CC1=CC=CC=N1 CSDSSGBPEUDDEE-UHFFFAOYSA-N 0.000 description 9
- BSKHPKMHTQYZBB-UHFFFAOYSA-N 2-methylpyridine Chemical compound CC1=CC=CC=N1 BSKHPKMHTQYZBB-UHFFFAOYSA-N 0.000 description 4
- OISVCGZHLKNMSJ-UHFFFAOYSA-N 2,6-dimethylpyridine Chemical compound CC1=CC=CC(C)=N1 OISVCGZHLKNMSJ-UHFFFAOYSA-N 0.000 description 3
- 150000001735 carboxylic acids Chemical class 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- FKNQCJSGGFJEIZ-UHFFFAOYSA-N 4-methylpyridine Chemical compound CC1=CC=NC=C1 FKNQCJSGGFJEIZ-UHFFFAOYSA-N 0.000 description 2
- AHISYUZBWDSPQL-UHFFFAOYSA-N 6-methylpyridine-2-carbaldehyde Chemical compound CC1=CC=CC(C=O)=N1 AHISYUZBWDSPQL-UHFFFAOYSA-N 0.000 description 2
- RTZKZFJDLAIYFH-UHFFFAOYSA-N Diethyl ether Chemical compound CCOCC RTZKZFJDLAIYFH-UHFFFAOYSA-N 0.000 description 2
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 2
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 2
- UIIMBOGNXHQVGW-UHFFFAOYSA-M Sodium bicarbonate Chemical compound [Na+].OC([O-])=O UIIMBOGNXHQVGW-UHFFFAOYSA-M 0.000 description 2
- LELOWRISYMNNSU-UHFFFAOYSA-N hydrogen cyanide Chemical compound N#C LELOWRISYMNNSU-UHFFFAOYSA-N 0.000 description 2
- 239000007788 liquid Substances 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- BGUWFUQJCDRPTL-UHFFFAOYSA-N pyridine-4-carbaldehyde Chemical compound O=CC1=CC=NC=C1 BGUWFUQJCDRPTL-UHFFFAOYSA-N 0.000 description 2
- 239000000741 silica gel Substances 0.000 description 2
- 229910002027 silica gel Inorganic materials 0.000 description 2
- BIAWAXVRXKIUQB-MDZDMXLPSA-N 2-[(e)-2-phenylethenyl]pyridine Chemical compound C=1C=CC=CC=1/C=C/C1=CC=CC=N1 BIAWAXVRXKIUQB-MDZDMXLPSA-N 0.000 description 1
- XWKFPIODWVPXLX-UHFFFAOYSA-N 2-methyl-5-methylpyridine Natural products CC1=CC=C(C)N=C1 XWKFPIODWVPXLX-UHFFFAOYSA-N 0.000 description 1
- VJVCDPKQQWTJDE-UHFFFAOYSA-N CC1=NC=CC=C1.[I] Chemical compound CC1=NC=CC=C1.[I] VJVCDPKQQWTJDE-UHFFFAOYSA-N 0.000 description 1
- ZOKXTWBITQBERF-UHFFFAOYSA-N Molybdenum Chemical compound [Mo] ZOKXTWBITQBERF-UHFFFAOYSA-N 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 150000003863 ammonium salts Chemical class 0.000 description 1
- 239000007864 aqueous solution Substances 0.000 description 1
- 239000000969 carrier Substances 0.000 description 1
- 239000000919 ceramic Substances 0.000 description 1
- 239000004927 clay Substances 0.000 description 1
- 239000003085 diluting agent Substances 0.000 description 1
- 238000004821 distillation Methods 0.000 description 1
- 239000000706 filtrate Substances 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 239000013067 intermediate product Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 229910044991 metal oxide Inorganic materials 0.000 description 1
- 150000004706 metal oxides Chemical class 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 229910052750 molybdenum Inorganic materials 0.000 description 1
- 239000011733 molybdenum Substances 0.000 description 1
- 229910052759 nickel Inorganic materials 0.000 description 1
- 238000006385 ozonation reaction Methods 0.000 description 1
- 238000001556 precipitation Methods 0.000 description 1
- 239000000047 product Substances 0.000 description 1
- 239000008262 pumice Substances 0.000 description 1
- QJZUKDFHGGYHMC-UHFFFAOYSA-N pyridine-3-carbaldehyde Chemical compound O=CC1=CC=CN=C1 QJZUKDFHGGYHMC-UHFFFAOYSA-N 0.000 description 1
- 150000003839 salts Chemical class 0.000 description 1
- 229910000030 sodium bicarbonate Inorganic materials 0.000 description 1
- 235000017557 sodium bicarbonate Nutrition 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
- 239000004575 stone Substances 0.000 description 1
- 230000007704 transition Effects 0.000 description 1
- 229910052720 vanadium Inorganic materials 0.000 description 1
- LEONUFNNVUYDNQ-UHFFFAOYSA-N vanadium atom Chemical compound [V] LEONUFNNVUYDNQ-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D213/00—Heterocyclic compounds containing six-membered rings, not condensed with other rings, with one nitrogen atom as the only ring hetero atom and three or more double bonds between ring members or between ring members and non-ring members
- C07D213/02—Heterocyclic compounds containing six-membered rings, not condensed with other rings, with one nitrogen atom as the only ring hetero atom and three or more double bonds between ring members or between ring members and non-ring members having three double bonds between ring members or between ring members and non-ring members
- C07D213/04—Heterocyclic compounds containing six-membered rings, not condensed with other rings, with one nitrogen atom as the only ring hetero atom and three or more double bonds between ring members or between ring members and non-ring members having three double bonds between ring members or between ring members and non-ring members having no bond between the ring nitrogen atom and a non-ring member or having only hydrogen or carbon atoms directly attached to the ring nitrogen atom
- C07D213/24—Heterocyclic compounds containing six-membered rings, not condensed with other rings, with one nitrogen atom as the only ring hetero atom and three or more double bonds between ring members or between ring members and non-ring members having three double bonds between ring members or between ring members and non-ring members having no bond between the ring nitrogen atom and a non-ring member or having only hydrogen or carbon atoms directly attached to the ring nitrogen atom with substituted hydrocarbon radicals attached to ring carbon atoms
- C07D213/44—Radicals substituted by doubly-bound oxygen, sulfur, or nitrogen atoms, or by two such atoms singly-bound to the same carbon atom
- C07D213/46—Oxygen atoms
- C07D213/48—Aldehydo radicals
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Pyridine Compounds (AREA)
Description
Verfahren zur Herstellung von Pyridinaldehyden Gegenstand des Patents 837 535 ist ein Verfahren zur Herstellung von Pyridoin. Dabei wird aus dampfförmigem Picolin durch Oxydation mit Sauerstoff und Katalysatoren Pyridoin hergestellt. Als Zwischenprodukt in dieser Reaktion wurde der Pyridinaldehyd vermutet, der sich unter Einfluß der spurenweise entstandenen Blausäure und des überschüssigen alkalischen Picolins zu Pyridoin dimerisiert.Process for the preparation of pyridine aldehydes the subject of the patent 837 535 is a process for making pyridoin. It is made of vapor Picoline produced by oxidation with oxygen and pyridoin catalysts. as An intermediate product in this reaction was suspected to be pyridine aldehyde, which is found under Influence of the traces of hydrogen cyanide and the excess alkaline acid Picolines dimerized to pyridoine.
Pyridinaldehyde sind in der Literatur bereits bekannt. Ihre Darstellung geschieht bisher auf mehr oder weniger großen Umwegen, u. a. durch Ozonisierung von Stilbazol, aus 2-Picolin-jod-methylat und aus o)-Trichlor-picolin. Keines der bisherigen Verfahren erlaubt eine technische Herstellung oder die Erzielung erheblicher Ausbeuten.Pyridinaldehydes are already known in the literature. Your representation has so far been done in more or less big detours, among other things. through ozonization from stilbazole, from 2-picoline iodine methylate and from o) -trichloropicoline. None of the previous methods allowed technical production or the achievement of considerable Exploit.
Es ist auch durch die deutsche Patentschrift 733 298 bekannt, Pyridinhomologe mit Luft und Katalysatoren zu den Carbonsäuren zu oxydieren. Es wurde nun gefunden, daß ein Luftüberschuß, der bei der Oxydation der Pyridinhomologen mit Luft und Katalysatoren zu den Carbonsäuren keineswegs schädlich ist, bei dem Verfahren zur Herstellung von Pyridoin oder Pyridinaldehyden gänzlich ungeeignet ist.It is also known from German patent specification 733 298, pyridine homologues to oxidize with air and catalysts to the carboxylic acids. It has now been found that an excess of air, which occurs in the oxidation of the pyridine homologues with air and catalysts to the carboxylic acids is in no way harmful in the process of preparation of pyridino or pyridine aldehydes is completely unsuitable.
Zur Herstellung von Pyridinaldehyden muß die Luftmenge zweckmäßig in der Nähe der theoretischen Menge gehalten werden, also bei r Mol Sauerstoff (02) auf z Mol einer CH. Gruppe.The amount of air must be appropriate for the production of pyridine aldehydes be kept close to the theoretical amount, i.e. at r moles of oxygen (02) on z moles of a CH. Group.
Beim erfindungsgemäßen Verfahren zur Herstellung von Pyridinaldehyden werden Homologe des Pyridins in Gegenwart der höchstens 4fachen theoretischen Sauerstoffmenge und mindestens des 3ofachen Volumens an inerten Verdünnungsmitteln unter Verwendung von Wasserdampf über Oxydationskatalysatoren bei erhöhter Temperatur geleitet, wobei ebenso wie bei dem Verfahren des Hauptpatents die Reaktionszone frei von Stoffen gehalten wird, die unter den Reaktionsbedingungen zu Eisenoxyd oder Kupferoxyd oxydiert werden. Die letztgenannte Maßnahme ist erforderlich, da sonst höhere Oxydationsprodukte, nämlich CO, und Carbonsäuren, gebildet werden. Zweckmäßig wird deshalb wie beim Verfahren des Hauptpatents als Ofenmaterial Edelstahl, Nickel oder Aluminium angewendet. Auch keramische Ofenauskleidungen sind brauchbar.In the process according to the invention for the preparation of pyridine aldehydes, homologues of pyridine are passed in the presence of at most 4 times the theoretical amount of oxygen and at least 3 times the volume of inert diluents using steam over oxidation catalysts at elevated temperature, the reaction zone being free of substances, as in the process of the main patent is held, which are oxidized to iron oxide or copper oxide under the reaction conditions. The last-mentioned measure is necessary because otherwise higher oxidation products, namely CO and carboxylic acids, are formed. Therefore, as in the process of the main patent, stainless steel, nickel or aluminum is expediently used as furnace material. Ceramic furnace linings can also be used.
Pyridoine und Pyridinaldehyde sind sehr verwandte Körper. Daher sind auch die Reaktionsbedingungen bei der Herstellung sehr ähnlich, und es hängt, wie aus dem Beispiel des Patents 837 535 und dem nachfolgenden Beispiel ersichtlich ist, nur von der Menge der angewandten Verdünnungsmittel ab; ob Pyridoine oder Pyridinaldehyde erhalten werden. Beträgt die Menge des Verdünnungsmittels bis zum 2ofachen des Dampfvolumens der eingesetzten Pyridinbasen, so wird bevorzugt Pyridoin gebildet; beträgt sie mehr als das 3ofache, so wird bevorzugt Pyridinaldehyd gebildet. Dazwischen sind Übergänge möglich, so daß Pyridoine und Pyridinaldehyde gleichzeitig nebeneinander gebildet werden.Pyridoins and pyridine aldehydes are very related bodies. Hence are also the reaction conditions in the preparation are very similar, and it depends how can be seen from the example of patent 837 535 and the example below depends only on the amount of diluents used; whether pyridoine or pyridine aldehyde can be obtained. The amount of thinner is up to 2 times the volume of the vapor of the pyridine bases used, pyridoin is preferably formed; it is more than threefold, pyridine aldehyde is preferentially formed. In between are Transitions possible, so that pyridoins and pyridinaldehydes next to one another at the same time are formed.
Als- Sauerstoffüberträger kommen die aus dem Schrifttum bekannten Oxydationskatalysatoren in Frage. Es ist zweckmäßig, die für die Oxydation geeigneten Metalle oder Metalloxyde auf oberflächenvergrößernden Stoffen, wie Bimsstein, Kieselgel, aktiver Tonerde, aufzutragen oder dieselben durch Fällung oder durch Erhitzung von Ammoniumsalzen zu erzeugen. Als besonders wirksam haben sich. bisher Vanadin bzw. Molybdän für sich allein oder in Kombination erwiesen.The oxygen carriers used are those known from literature Oxidation catalysts in question. It is advisable to use those suitable for oxidation Metals or metal oxides on surface-enlarging materials such as pumice stone, silica gel, active clay, to be applied or the same by precipitation or by heating Generate ammonium salts. Have proven to be particularly effective. so far vanadium or Molybdenum has been shown on its own or in combination.
Von den bekannten Arbeitsweisen zur Oxydation von Pyridinhomologen im Dampfzustand mit Sauerstoff über Oxydationskatalysatoren bei erhöhter Temperatur ist das vorliegende Verfahren zur Herstellung von Pyridinaldehyden unterschieden erstens durch die begrenzte Luftmenge, zweitens durch die Menge des zugesetzten inerten Verdünnungsmittels, drittens durch die Abwesenheit von Stoffen, die in der Reaktionszone in Eisenoxyd oder Kupferoxyd übergehen können. Nach dem vorliegenden Verfahren können Pyridinaldehyde mit guter Ausbeute (700/, und mehr) leicht und in technischem Ausmaß hergestellt werden.From the known procedures for the oxidation of pyridine homologues in the vapor state with oxygen over oxidation catalysts at elevated temperature, the present process for the production of pyridine aldehydes is distinguished first by the limited amount of air, second by the amount of inert diluent added, third by the absence of substances in the reaction zone can change into iron oxide or copper oxide. According to the present process, pyridine aldehydes can be produced easily and on an industrial scale with good yield (700 /, and more).
Beispiel Über zoo ccm eines Katalysators, der aus go °/a Silicagel und zo°/o Mo03/V206 Gemisch (30/7o) besteht, leitet man bei 35o bis 45o°, am besten bei 41o°, in der Stunde 5o 1 Luft sowie den Dampf aus 350 ccm einer 5°/oigen wäßrigen Lösung von 2-Picolin. Die den Kontaktraum verlassenden Dämpfe werden kondensiert, und man erhält eine tiefblaue, stark nach Pyridinaldehyd riechende Flüssigkeit. Das Destillat wird bis auf PH 3,5 angesäuert und anschließend im Vakuum bis zur öligen Konsistenz eingedampft. Zur Freisetzung des Pyridinaldehyds wird mit Natriumbicarbonat versetzt, das ausgefällte Salz abgesaugt und das Filtrat mit Äther ausgeschüttelt. Durch Destillation erhält man reinen Pyridinaldehyd-(2) vom Kpls 7o bis 7r°.Example 50 1 air per hour is passed over zoo cc of a catalyst consisting of 100% silica gel and 100% Mo03 / V206 mixture (30/70) at 35o to 45o °, preferably at 41o ° and the steam from 350 cc of a 5% aqueous solution of 2-picoline. The vapors leaving the contact area are condensed and a deep blue liquid with a strong smell of pyridine aldehyde is obtained. The distillate is acidified to pH 3.5 and then evaporated in vacuo to an oily consistency. To release the pyridine aldehyde, sodium bicarbonate is added, the precipitated salt is filtered off with suction and the filtrate is shaken out with ether. Pure pyridine aldehyde (2) with a cpls of 70 to 70 ° is obtained by distillation.
In ähnlicher Weise erhält man aus 2, 6-Lutidin den 6-Methyl-pyridin-2-aldehyd, Kp" 77 bis 78° Fp 30°, aus 4-Picolin den Pyridin-4-aldehyd, Kp12 8z bis 82°; farblose Flüssigkeit von 4-picolinähnlichem, aber stechendem Geruch und brennendem Geschmack, aus technischem »ß-Picolina ein Gemisch von Pyridin-3-aldehyd, Pyridin-4-aldehyd und 6-Methyl-pyridin-2-aldehyd, Kp" 79 bis 8i°.In a similar way, 6-methyl-pyridine-2-aldehyde is obtained from 2,6-lutidine, b.p. 77 to 78 °, mp 30 °, from 4-picoline, pyridine-4-aldehyde, b.p. 12.8 ° to 82 °; colorless Liquid of 4-picolin-like, but pungent odor and burning taste, from technical »ß-Picolina a mixture of pyridine-3-aldehyde, pyridine-4-aldehyde and 6-methyl-pyridine-2-aldehyde, bp" 79 to 81 ° .
Claims (1)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DER15628A DE936871C (en) | 1951-10-21 | 1951-10-21 | Process for the preparation of pyridine aldehydes |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DER15628A DE936871C (en) | 1951-10-21 | 1951-10-21 | Process for the preparation of pyridine aldehydes |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| DE936871C true DE936871C (en) | 1955-12-22 |
Family
ID=7399568
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| DER15628A Expired DE936871C (en) | 1951-10-21 | 1951-10-21 | Process for the preparation of pyridine aldehydes |
Country Status (1)
| Country | Link |
|---|---|
| DE (1) | DE936871C (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE1088958B (en) * | 1957-04-12 | 1960-09-15 | Cfmc | Process for the preparation of pyridine aldehydes |
| DE1220423B (en) * | 1959-06-24 | 1966-07-07 | Raschig Gmbh Dr F | Process for the preparation of pyridine aldehydes |
-
1951
- 1951-10-21 DE DER15628A patent/DE936871C/en not_active Expired
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE1088958B (en) * | 1957-04-12 | 1960-09-15 | Cfmc | Process for the preparation of pyridine aldehydes |
| DE1220423B (en) * | 1959-06-24 | 1966-07-07 | Raschig Gmbh Dr F | Process for the preparation of pyridine aldehydes |
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