CH412933A - Process for the preparation of 2,5,7,8-tetramethyl-2- (2'-carboxy-ethyl) -chroman-6-ol - Google Patents
Process for the preparation of 2,5,7,8-tetramethyl-2- (2'-carboxy-ethyl) -chroman-6-olInfo
- Publication number
- CH412933A CH412933A CH367362A CH367362A CH412933A CH 412933 A CH412933 A CH 412933A CH 367362 A CH367362 A CH 367362A CH 367362 A CH367362 A CH 367362A CH 412933 A CH412933 A CH 412933A
- Authority
- CH
- Switzerland
- Prior art keywords
- carboxy
- preparation
- chroman
- boron trifluoride
- condensation
- Prior art date
Links
- 238000000034 method Methods 0.000 title claims description 12
- 238000002360 preparation method Methods 0.000 title claims description 6
- AXODOWFEFKOVSH-UHFFFAOYSA-N alpha-CEHC Chemical compound O1C(C)(CCC(O)=O)CCC2=C1C(C)=C(C)C(O)=C2C AXODOWFEFKOVSH-UHFFFAOYSA-N 0.000 title claims description 4
- KZMGYPLQYOPHEL-UHFFFAOYSA-N Boron trifluoride etherate Chemical compound FB(F)F.CCOCC KZMGYPLQYOPHEL-UHFFFAOYSA-N 0.000 claims description 10
- 238000006243 chemical reaction Methods 0.000 claims description 10
- WTEOIRVLGSZEPR-UHFFFAOYSA-N boron trifluoride Chemical compound FB(F)F WTEOIRVLGSZEPR-UHFFFAOYSA-N 0.000 claims description 8
- 238000009833 condensation Methods 0.000 claims description 7
- 230000005494 condensation Effects 0.000 claims description 7
- KRHYYFGTRYWZRS-UHFFFAOYSA-N Fluorane Chemical compound F KRHYYFGTRYWZRS-UHFFFAOYSA-N 0.000 claims description 5
- 229910000040 hydrogen fluoride Inorganic materials 0.000 claims description 5
- AUFZRCJENRSRLY-UHFFFAOYSA-N 2,3,5-trimethylhydroquinone Chemical compound CC1=CC(O)=C(C)C(C)=C1O AUFZRCJENRSRLY-UHFFFAOYSA-N 0.000 claims description 4
- 229910015900 BF3 Inorganic materials 0.000 claims description 4
- RTZKZFJDLAIYFH-UHFFFAOYSA-N Diethyl ether Chemical compound CCOCC RTZKZFJDLAIYFH-UHFFFAOYSA-N 0.000 claims description 4
- 239000012442 inert solvent Substances 0.000 claims description 4
- 239000000203 mixture Substances 0.000 claims description 4
- ZAFNJMIOTHYJRJ-UHFFFAOYSA-N Diisopropyl ether Chemical compound CC(C)OC(C)C ZAFNJMIOTHYJRJ-UHFFFAOYSA-N 0.000 claims description 2
- 229910021578 Iron(III) chloride Inorganic materials 0.000 claims description 2
- 229930195733 hydrocarbon Natural products 0.000 claims description 2
- 150000002430 hydrocarbons Chemical class 0.000 claims description 2
- RBTARNINKXHZNM-UHFFFAOYSA-K iron trichloride Chemical compound Cl[Fe](Cl)Cl RBTARNINKXHZNM-UHFFFAOYSA-K 0.000 claims description 2
- 239000004215 Carbon black (E152) Substances 0.000 claims 1
- GAEKPEKOJKCEMS-UHFFFAOYSA-N gamma-valerolactone Chemical compound CC1CCC(=O)O1 GAEKPEKOJKCEMS-UHFFFAOYSA-N 0.000 claims 1
- 230000003647 oxidation Effects 0.000 claims 1
- 238000007254 oxidation reaction Methods 0.000 claims 1
- 229920002554 vinyl polymer Polymers 0.000 claims 1
- 150000002596 lactones Chemical class 0.000 description 7
- SEBPXHSZHLFWRL-UHFFFAOYSA-N 3,4-dihydro-2,2,5,7,8-pentamethyl-2h-1-benzopyran-6-ol Chemical compound O1C(C)(C)CCC2=C1C(C)=C(C)C(O)=C2C SEBPXHSZHLFWRL-UHFFFAOYSA-N 0.000 description 6
- QTBSBXVTEAMEQO-UHFFFAOYSA-N Acetic acid Chemical compound CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 description 3
- WFDIJRYMOXRFFG-UHFFFAOYSA-N Acetic anhydride Chemical compound CC(=O)OC(C)=O WFDIJRYMOXRFFG-UHFFFAOYSA-N 0.000 description 3
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 3
- 150000001875 compounds Chemical class 0.000 description 3
- GVJHHUAWPYXKBD-UHFFFAOYSA-N (±)-α-Tocopherol Chemical compound OC1=C(C)C(C)=C2OC(CCCC(C)CCCC(C)CCCC(C)C)(C)CCC2=C1C GVJHHUAWPYXKBD-UHFFFAOYSA-N 0.000 description 2
- OZJPLYNZGCXSJM-UHFFFAOYSA-N 5-valerolactone Chemical compound O=C1CCCCO1 OZJPLYNZGCXSJM-UHFFFAOYSA-N 0.000 description 2
- UIIMBOGNXHQVGW-UHFFFAOYSA-M Sodium bicarbonate Chemical compound [Na+].OC([O-])=O UIIMBOGNXHQVGW-UHFFFAOYSA-M 0.000 description 2
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 2
- 239000002253 acid Substances 0.000 description 2
- OZECDDHOAMNMQI-UHFFFAOYSA-H cerium(3+);trisulfate Chemical compound [Ce+3].[Ce+3].[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O OZECDDHOAMNMQI-UHFFFAOYSA-H 0.000 description 2
- 230000002503 metabolic effect Effects 0.000 description 2
- 239000000047 product Substances 0.000 description 2
- 239000011541 reaction mixture Substances 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- JIAARYAFYJHUJI-UHFFFAOYSA-L zinc dichloride Chemical compound [Cl-].[Cl-].[Zn+2] JIAARYAFYJHUJI-UHFFFAOYSA-L 0.000 description 2
- HTSGKJQDMSTCGS-UHFFFAOYSA-N 1,4-bis(4-chlorophenyl)-2-(4-methylphenyl)sulfonylbutane-1,4-dione Chemical compound C1=CC(C)=CC=C1S(=O)(=O)C(C(=O)C=1C=CC(Cl)=CC=1)CC(=O)C1=CC=C(Cl)C=C1 HTSGKJQDMSTCGS-UHFFFAOYSA-N 0.000 description 1
- QESPSAHXYXIGBG-UHFFFAOYSA-N 5-ethenyl-5-methyloxolan-2-one Chemical compound C=CC1(C)CCC(=O)O1 QESPSAHXYXIGBG-UHFFFAOYSA-N 0.000 description 1
- UIIMBOGNXHQVGW-DEQYMQKBSA-M Sodium bicarbonate-14C Chemical compound [Na+].O[14C]([O-])=O UIIMBOGNXHQVGW-DEQYMQKBSA-M 0.000 description 1
- LRYFTDGIIUTFFA-UHFFFAOYSA-N Tocopheronic acid Chemical compound CC1=C(C)C(=O)C(CCC(C)(O)CCC(O)=O)=C(C)C1=O LRYFTDGIIUTFFA-UHFFFAOYSA-N 0.000 description 1
- 229930003427 Vitamin E Natural products 0.000 description 1
- 150000001242 acetic acid derivatives Chemical class 0.000 description 1
- 239000008346 aqueous phase Substances 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 239000006227 byproduct Substances 0.000 description 1
- 230000003197 catalytic effect Effects 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 238000000354 decomposition reaction Methods 0.000 description 1
- 230000032050 esterification Effects 0.000 description 1
- 238000005886 esterification reaction Methods 0.000 description 1
- 150000002170 ethers Chemical class 0.000 description 1
- 238000000605 extraction Methods 0.000 description 1
- WIGCFUFOHFEKBI-UHFFFAOYSA-N gamma-tocopherol Natural products CC(C)CCCC(C)CCCC(C)CCCC1CCC2C(C)C(O)C(C)C(C)C2O1 WIGCFUFOHFEKBI-UHFFFAOYSA-N 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 230000020477 pH reduction Effects 0.000 description 1
- 238000001953 recrystallisation Methods 0.000 description 1
- 235000017557 sodium bicarbonate Nutrition 0.000 description 1
- 229910000030 sodium bicarbonate Inorganic materials 0.000 description 1
- 239000002904 solvent Substances 0.000 description 1
- 238000003786 synthesis reaction Methods 0.000 description 1
- 229930003231 vitamin Natural products 0.000 description 1
- 239000011782 vitamin Substances 0.000 description 1
- 229940088594 vitamin Drugs 0.000 description 1
- 235000013343 vitamin Nutrition 0.000 description 1
- 229940046009 vitamin E Drugs 0.000 description 1
- 235000019165 vitamin E Nutrition 0.000 description 1
- 239000011709 vitamin E Substances 0.000 description 1
- 150000003722 vitamin derivatives Chemical class 0.000 description 1
- 235000005074 zinc chloride Nutrition 0.000 description 1
- 239000011592 zinc chloride Substances 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C66/00—Quinone carboxylic acids
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D311/00—Heterocyclic compounds containing six-membered rings having one oxygen atom as the only hetero atom, condensed with other rings
- C07D311/02—Heterocyclic compounds containing six-membered rings having one oxygen atom as the only hetero atom, condensed with other rings ortho- or peri-condensed with carbocyclic rings or ring systems
- C07D311/04—Benzo[b]pyrans, not hydrogenated in the carbocyclic ring
- C07D311/58—Benzo[b]pyrans, not hydrogenated in the carbocyclic ring other than with oxygen or sulphur atoms in position 2 or 4
- C07D311/70—Benzo[b]pyrans, not hydrogenated in the carbocyclic ring other than with oxygen or sulphur atoms in position 2 or 4 with two hydrocarbon radicals attached in position 2 and elements other than carbon and hydrogen in position 6
- C07D311/72—3,4-Dihydro derivatives having in position 2 at least one methyl radical and in position 6 one oxygen atom, e.g. tocopherols
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
- Heterocyclic Carbon Compounds Containing A Hetero Ring Having Oxygen Or Sulfur (AREA)
- Pyrane Compounds (AREA)
Description
Verfahren zur Herstellung von 2,5,7, 8-Tetramethyl-2- (2'-carboxy-äthyl)-chroman-6-ol
Die vorliegende Erfindung betrifft ein Verfahren zur Herstellung eines Chromanols, welches als Zwischenprodukt zur Herstellung von 2-(3'-Hydroxy-3' methyl-5'-carboxy-pentyl) -3,5,6 - trimethyl-benzochi- non (I) und dem entsprechenden Lacton, dem Tocopheronlacton (II) dient. Die beiden letztgenannten Verbindungen haben die Formeln
EMI1.1
Diese Verbindungen wurden bisher isoliert von Simon, Eisengart, Sundheim & Milhorat [J. Biol.
Chem. (1956) 221, 807] als metabolische Produkte des Vitamins E. Es wird angenommen, dass die genannten Stoffe aktive metabolische Formen des Vitamins darstellen. Die Verbindung II wurde kürzlich synthetisch hergestellt von Weichet, Blaha und Kakac [Coll. Ezech. Chem. Commun. (1959) 24, 1689] auf folgendem Wege: y-Vinyl-y-valerolacton (III) wurde kondensiert mit 2,3,5 -Trimethyl-hydrochinon (IV) in Gegenwart einer Kondensationsmischung, bestehend aus Essigsäure, wasserfreiem Zinkchlorid, Bortrifluoridätherat und Essigsäureanhydrid, wobei das Chromanol (V) entsteht, das in der Folge mit Cerisulfat zum Lacton (II) umgesetzt wurde.
Die Kondensation verläuft nach folgendem Schema:
EMI1.2
Unter den genannten Reaktionsbedingungen tritt eine beträchtliche Zersetzung ein und es entstehen schwarze und teerartige Nebenprodukte. Die Reaktion ist sehr schwierig auszuführen und verlangt mühsame Extraktionsoperationen. Obschon von den genannten Autoren 60% Ausbeute angegeben worden war, sind die Ausbeuten an reiner Substanz in der Praxis viel niedriger und betragen gewöhnlich nur 25 %. Ein weiterer Nachteil des angegebenen Verfahrens ist der, dass eine Veresterung eintritt und das Produkt V in Form eines Acetates erhalten wird, welches unter alkalischen Reaktionsbedingungen zu der freien Verbindung V hydrolysiert werden muss.
Dementsprechend ist das angegebene Verfahren nicht nur schwierig auszuführen und führt zu niedrigen Ausbeuten, sondern es ist auch unwirtschaftlich und verlangt einen unerwünschten zusätzlichen Schritt innerhalb der Synthese.
Das erfindungsgemässe Verfahren zur Herstellung von
2,5 ,7,8-Tetramethyl-2-(2'-carboxy-äthyl) chroman-6-ol durch Kondensation von y-Vinyl-y-valerolacton mit 2,3,5-Trimethylhydrochinon ist nunmehr dadurch gekennzeichnet, dass die Reaktion unter milden Bedingungen in einem inerten Lösungsmittel in Gegenwart von katalytischen Mengen von Bortrifluorid als Kondensationsmittel und in Gegenwart von Fluorwasserstoff im Kondensationsgemisch durchgeführt wird.
Normalerweise enthält das handelsübliche Bortri fluoridätherat genügende Mengen an freiem Fluorwasserstoff, um die Reaktion zu katalysieren. Wenn indessen gereinigtes Bortrifluoridätherat verwendet wird, muss dem Reaktionsgemenge Fluorwasserstoff zugesetzt werden. Zur Durchführung der Reaktion unter milden Reaktionsbedingungen ist es zweckmässig, bei so niedriger Temperatur zu arbeiten, dass gerade noch ein glatter Reaktionsverlauf zwischen den Reaktionskomponenten stattfindet. Im allgemei nen wird man zwischen Zimmertemperatur und
1500 C, vorzugsweise zwischen 80 und 1200 C, arbeiten. Als inerte Lösungsmittel eignen sich Kohlenwasserstoffe, Äther und andere Lösungsmittel, wie sie üblicherweise Verwendung finden und deren Zusammensetzung weiter nicht kritsch ist.
Der Anteil an Bortrifluoridätherat ist ebenfalls nicht kritisch und wird mit Vorteil zwischen 1 und 20 Gew.-S des Lactons III gehalten. Das erhaltene Chromanol der Formel V in unveresterter Form lässt sich aus dem Reaktionsgemenge leicht mit Natriumbicarbonat extrahieren, wobei es aus der Lösung des letzteren vermittels Säure auf einfache Weise regeneriert werden kann. Die Ausbeute an dem aus dem Chromanol der Formel V durch Weiterverarbeitung erhaltenen Tocopheronlacton der Formel II, berechnet auf das Ausgangsgewicht an Lactan III, liegt zwischen 80 und 100%.
Ein weiterer Vorteil bei der Gewinnung des Lactons II ist der, dass bei der Oxydation des Chromanols V das Cerisulfat durch das billigere Ferrichlorid ersetzt werden kann. Es lässt sich auf diese Weise die Säure I herstellen, die nach bekannten Methoden auf einfache Weise zum gewünschten Lacton II umgesetzt werden kann.
Im folgenden Beispiel sind die angegebenen Teile Gewichtsteile.
Beispiel
15 Teile 2,3,5-Trimethyl-hydrochinon, 12,5 Teile y-Vinyl-y-valerolacton und 2 Teile Bortrifluoridätherat in 200 Teilen Isopropyläther wurden am Rückfluss 5 Stunden lang erhitzt. Nach dem Abkühlen wurde die Lösung mit wässriger Natriumbicarbonatlösung extrahiert. Ansäuren der wässrigen Phase mit Schwefelsäure ergab das Chromanol der Formel V, das nach dem Umkristallisieren aus 50% im wässrigem Methanol bei 1730 C schmolz. Die Ausbeute betrug 80%, berechnet auf das Valerolacton.
Process for the preparation of 2,5,7,8-tetramethyl-2- (2'-carboxy-ethyl) -chroman-6-ol
The present invention relates to a process for the preparation of a chromanol which is used as an intermediate for the preparation of 2- (3'-hydroxy-3 'methyl-5'-carboxy-pentyl) -3,5,6-trimethyl-benzoquinone (I. ) and the corresponding lactone, the tocopherone lactone (II). The latter two compounds have the formulas
EMI1.1
These compounds have been isolated to date by Simon, Eisengart, Sundheim & Milhorat [J. Biol.
Chem. (1956) 221, 807] as metabolic products of vitamin E. It is assumed that the substances mentioned represent active metabolic forms of the vitamin. Compound II was recently synthesized by Weichet, Blaha and Kakac [Coll. Ezech. Chem. Commun. (1959) 24, 1689] in the following way: y-vinyl-y-valerolactone (III) was condensed with 2,3,5-trimethyl-hydroquinone (IV) in the presence of a condensation mixture consisting of acetic acid, anhydrous zinc chloride, boron trifluoride etherate and Acetic anhydride, whereby the chromanol (V) is formed, which was then reacted with cerium sulfate to form the lactone (II).
The condensation proceeds according to the following scheme:
EMI1.2
Considerable decomposition occurs under the reaction conditions mentioned and black and tarry by-products are formed. The reaction is very difficult to carry out and requires troublesome extraction operations. Although 60% yield was given by the authors mentioned, the yields of pure substance are much lower in practice and are usually only 25%. Another disadvantage of the specified process is that esterification occurs and the product V is obtained in the form of an acetate, which has to be hydrolyzed to the free compound V under alkaline reaction conditions.
Accordingly, the specified process is not only difficult to carry out and leads to low yields, but it is also uneconomical and requires an undesirable additional step in the synthesis.
The inventive method for the production of
2,5, 7,8-Tetramethyl-2- (2'-carboxy-ethyl) chroman-6-ol by condensation of y-vinyl-y-valerolactone with 2,3,5-trimethylhydroquinone is now characterized in that the Reaction is carried out under mild conditions in an inert solvent in the presence of catalytic amounts of boron trifluoride as the condensing agent and in the presence of hydrogen fluoride in the condensation mixture.
The commercially available boron tri fluoride etherate normally contains sufficient amounts of free hydrogen fluoride to catalyze the reaction. If, however, purified boron trifluoride etherate is used, hydrogen fluoride must be added to the reaction mixture. To carry out the reaction under mild reaction conditions, it is expedient to work at such a low temperature that a smooth reaction process takes place between the reaction components. In general, you will be between room temperature and
1500 C, preferably between 80 and 1200 C, work. Suitable inert solvents are hydrocarbons, ethers and other solvents such as are usually used and the composition of which is furthermore not critical.
The proportion of boron trifluoride etherate is also not critical and is advantageously kept between 1 and 20% by weight of the lactone III. The chromanol of the formula V obtained in unesterified form can easily be extracted from the reaction mixture with sodium bicarbonate, and it can be regenerated in a simple manner from the solution of the latter by means of acid. The yield of the tocopherone lactone of the formula II obtained from the chromanol of the formula V by further processing, calculated on the starting weight of lactan III, is between 80 and 100%.
Another advantage of obtaining lactone II is that when the chromanol V is oxidized, the cerium sulfate can be replaced by the cheaper ferric chloride. In this way, the acid I can be prepared, which can be converted to the desired lactone II in a simple manner by known methods.
In the following example the parts given are parts by weight.
example
15 parts of 2,3,5-trimethyl-hydroquinone, 12.5 parts of γ-vinyl-γ-valerolactone and 2 parts of boron trifluoride ether in 200 parts of isopropyl ether were refluxed for 5 hours. After cooling, the solution was extracted with aqueous sodium bicarbonate solution. Acidification of the aqueous phase with sulfuric acid gave the chromanol of the formula V, which melted at 1730 C after recrystallization from 50% in aqueous methanol. The yield was 80%, calculated on the valerolactone.
Claims (1)
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB1322061A GB947885A (en) | 1961-04-12 | 1961-04-12 | Improvements in or relating to the preparation of chromanols |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CH412933A true CH412933A (en) | 1966-05-15 |
Family
ID=10019011
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CH367362A CH412933A (en) | 1961-04-12 | 1962-03-27 | Process for the preparation of 2,5,7,8-tetramethyl-2- (2'-carboxy-ethyl) -chroman-6-ol |
Country Status (2)
| Country | Link |
|---|---|
| CH (1) | CH412933A (en) |
| GB (1) | GB947885A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1996005191A1 (en) * | 1994-08-15 | 1996-02-22 | Loma Linda University Medical Center | Natriuretic cyclic compounds |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5120843A (en) * | 1987-04-27 | 1992-06-09 | Upjohn | Pharmaceutically active amines |
-
1961
- 1961-04-12 GB GB1322061A patent/GB947885A/en not_active Expired
-
1962
- 1962-03-27 CH CH367362A patent/CH412933A/en unknown
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1996005191A1 (en) * | 1994-08-15 | 1996-02-22 | Loma Linda University Medical Center | Natriuretic cyclic compounds |
| US6083982A (en) * | 1994-08-15 | 2000-07-04 | Loma Linda University Medical | Natriuretic compounds |
| US6150402A (en) * | 1994-08-15 | 2000-11-21 | Loma Linda University Medical Center | Natriuretic compounds |
Also Published As
| Publication number | Publication date |
|---|---|
| GB947885A (en) | 1964-01-29 |
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