WO1998018806A1 - Verfahren zur herstellung von ivermectin - Google Patents
Verfahren zur herstellung von ivermectin Download PDFInfo
- Publication number
- WO1998018806A1 WO1998018806A1 PCT/EP1997/005777 EP9705777W WO9818806A1 WO 1998018806 A1 WO1998018806 A1 WO 1998018806A1 EP 9705777 W EP9705777 W EP 9705777W WO 9818806 A1 WO9818806 A1 WO 9818806A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- hydrogenation
- product
- catalyst
- ivermectin
- rhodium
- Prior art date
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07H—SUGARS; DERIVATIVES THEREOF; NUCLEOSIDES; NUCLEOTIDES; NUCLEIC ACIDS
- C07H17/00—Compounds containing heterocyclic radicals directly attached to hetero atoms of saccharide radicals
- C07H17/04—Heterocyclic radicals containing only oxygen as ring hetero atoms
- C07H17/08—Hetero rings containing eight or more ring members, e.g. erythromycins
Definitions
- the present invention relates to a process for the preparation of ivermectin by selective hydrogenation of avermectin and subsequent separation of the
- Ivermectin is a known compound that has excellent biological effects and is widely used as an anthelmintic, ectoparasiticide, insecticide and acaricide.
- Avermectin B la (R: -ethyl)
- Avermectin B lb (R: -Methyl)
- This process described in EP-A 59 616 includes the treatment of the after
- the present invention relates to a process for the preparation of ivermectin which allows both the rhodium used and the organic components of the catalyst system to be separated off in a simple manner from the product solution obtained after the hydrogenation, in order to obtain an active ingredient which has little material loss an application-appropriate form can be processed
- avermectin B la and B lb are hydrogenated and both the catalyst metal and the organic components of the catalyst system are separated off in a simple manner from the reaction solutions obtained
- mixtures of avermectin B la and B ] b are obtained by selective hydrogenation using catalysts which are obtained in a manner known per se from rhodium salts or rhodium complex compounds and phosphines, optionally with the addition of hydrazine or hydrazine salts,
- R, R and R independently of one another represent hydrogen, alkyl, or arylalkyl optionally substituted by alkyl, alkoxy, halogen or haloalkyl,
- n , m 2 and m 3 are the same or different and are 0 or 1,
- the sum of the carbon atoms contained in the alkyl and alkoxy groups is at least 12,
- the production processes for the catalysts are known (see, for example, Inorg Synth 10, 67 (1967) and EP-A 0 086 040, EP-A 0 283 615 and Tetrahedron Vol 7, No 19/20, S 2087-2089 (1988))
- the rhodium compounds which are suitable as starting compounds for the preparation of the catalysts are known, for example rhodium (III) chloride hydrate and rhodium (III) bromide hydrate may be mentioned as rhodium salts, as suitable precursors from the series of rhodium complex compounds rhodium (I ) - (lc, 5c-cyclooctadiene) chloride dimer, rhodium (I) - (l, 5-hexadiene) chloride dimer and rhodium (I) - (2,5-norbornadiene) chloride dimer and rhodium (I) - (1,5-Cyclooctad ⁇ en)
- phosphines of the formula (I) used according to the invention are known or can be prepared by known processes (see Houben-Weyl, Methods of Organic Chemistry, 4 editions, vol. XII / 1, Georg Thieme Verlag Stuttgart, 1963)
- Phosphines of the formula are preferably used in the process according to the invention.
- Halogen-C j -C 4 alkyl in particular trifluoromethyl substituted aryl-C j - C 4 alkyl, in particular benzyl or phenylethyl, and in which is independent of one another
- Halogen-C j -C 4 alkyl especially trifluoromethyl-substituted aryl-C,
- C 4 alkyl in particular benzyl or phenylethyl, and in which is independent of one another
- the sum of the carbon atoms in the alkyl or alkoxy groups being at least 12, preferably at least 15 and particularly preferably at least 18
- the catalysts can be isolated after production and used in pure form for the hydrogenation. However, it is also possible and particularly expedient to synthesize the catalysts in situ and to use correspondingly obtained solutions for the selective hydrogenation. It can be advantageous to use the hydrogenation mixture as Ligand used to add an excess of phosphine Rhodium salts and phosphines of the formula (I) in a molar ratio of 1 1 to 1.20, preferably 1 1 to 1.15, particularly preferably 1 3 to 1 15 are used to prepare the catalyst system (cf. in particular EP-A 0 086 046). Hydrazine or its derivatives is optionally used in a molar ratio to rhodium salt 1 1 to 1 10 added
- the amount of additional phosphine of the formula (I) added in the process according to the invention is in the order of 0.01 to 0.06 mol based on 1 mol of substrate (cf. EP-A 0 086 046). The most favorable amount can, however, easily be carried out in a series of tests be determined
- the catalytic hydrogenation is carried out in customary solvents, such as, for example, alcohols, aromatic hydrocarbons, in ethers, ketones, esters or in mixtures of solvents, for example in methanol or acetone-hydrocarbon mixtures
- customary solvents such as, for example, alcohols, aromatic hydrocarbons, in ethers, ketones, esters or in mixtures of solvents, for example in methanol or acetone-hydrocarbon mixtures
- the temperature during the hydrogenation is in the range from approx. 40 to 100.degree. C., the hydrogen pressure in the range from approx. 1 to 50 bar. In order to shorten the reaction time, it is advisable to work at elevated pressure, a range from 3 to 20 bar being preferred
- the lipophilic properties of the phosphines used as catalyst hand according to the invention enable simple extractive separation of the catalyst system from the product with the aid of suitable lipophilic solvents in which the process product (ivermectin) is insoluble or only slightly soluble
- the solvent can be removed by vacuum distillation and then the catalyst system (metal complex and phosphine) can be removed from the remaining product-catalyst mixture by stirring with lipophilic solvents B can be obtained in a highly pure form by a subsequent, known recrystallization, which is used to separate small amounts of by-products.
- the catalyst system metal complex and phosphine
- Lipophilic solvents such as aliphatic hydrocarbons are suitable for the selective removal of the catalyst system - cyclohexane, methyl cyclohexane, isooctane, petroleum ether, mineral spirits or ethers with larger hydrocarbon radicals, such as, for example, tert-octyl methyl ether, may be mentioned as examples
- a variant for separating the catalyst system after the hydrogenation is that the selective, lipophilic solvent is added to the product catalyst solution which is obtained after the selective hydrogenation and the polar solvent component obtained in the hydrogenation is removed by distillation. Separation occurs, the ivermectin precipitates and can be separated from the solution containing the catalyst system by decanting or filtration.
- a further variant for separating the catalyst system after the hydrogenation stage consists in subsequently producing a two-phase mixture which allows the ivermectin to be separated from the catalyst system (catalyst complex and excess phosphine). If necessary, the solvent used for the hydrogenation stage is distilled, expediently to protect the product mixture under reduced pressure, removed and replaced by a solvent mixture suitable for the separation
- Solvent mixtures suitable for this variant of the separation consist of a lipophilic component (see above) and of polar solvents which are miscible with water, and water.
- the polar components for such solvent mixtures are, for example, methanol, ethanol, acetone, butanone, acetonitrile, tetrahydrofuran, formamide , Dimethylformamide and N-methylpyrrolidone.
- the water content of such solvent mixtures can vary depending on the selection of the components, it is generally 5 to 60%, preferably 10 to 40%.
- a further embodiment of the process according to the invention is to use solvents or solvent mixtures which dissolve the educt and product and the catalyst system at elevated temperature, which corresponds to the hydrogenation conditions, and from which the desired product (ivermectin) subsequently precipitates after sufficient cooling, in which, however, the metal complex catalyst and the ligandphosphine remain dissolved even at a reduced temperature.
- the product of the process largely freed from the catalyst, can be separated from the residual solution by filtration, while the catalyst metal is obtained in a simple manner by working up by distillation in the distillation residue and fed to the reprocessing.
- Such solvents are characterized by amphiphilic properties and have a lipophilic portion and polar groups.
- Examples include isooctanol, dodecanol, methyl tert-octyl ether, mixtures of tert-butanol and isooctane, and tert-butyl methyl ether and isooctane.
- Catalyst systems enable both an excellent selective hydrogenation of avermectins to ivermectins and a simple separation of product and catalyst system.
- the catalyst solution obtained according to (A) is added to a solution of 4.3 g of avermectin (B la and B ] b mixture) in 25 ml of a mixture of acetone and cyclohexane in the ratio 2 1. After adding 51.4 mg
- Tris (hexylphenyl) -phosphine the hydrogenation is carried out in a steel autoclave at 5 bar hydrogen pressure and 88 ° C. After 4 hours of hydrogenation, HPLC analysis shows a content of 8.9% starting material, 89.9% ivermectin (B la - and B ] b mixture), content of tetra-hydroavermectin ⁇ 0.1%
- the crude product obtained according to (B) is dissolved in a mixture of 35 ml of methanol and 20 ml of water, this solution is extracted in a shaking funnel with 25 ml of cyclohexane. The phases are separated and concentrated in vacuo
- the product obtained after the 1 extraction 39 ppm Rh after the 2 extraction 29 ppm Rh after the 3 extraction 22 ppm Rh The catalyst system (catalyst and phosphine) extracted from the product contains 6 332 ppm Rh
- Example 1 53.2 mg of T ⁇ s- (octylphenyl) -phosph ⁇ n hydrogenated under the conditions given in Example 1 (B). After 7 hours of hydrogenation, an ivermecin crude product is obtained which, according to HPLC analysis, contains 1.3% avermectin, 94.8% ivermectin and 2% Tetrahydroavermectm contains
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- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Molecular Biology (AREA)
- Life Sciences & Earth Sciences (AREA)
- Biochemistry (AREA)
- Biotechnology (AREA)
- General Health & Medical Sciences (AREA)
- Genetics & Genomics (AREA)
- Health & Medical Sciences (AREA)
- Engineering & Computer Science (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
- Low-Molecular Organic Synthesis Reactions Using Catalysts (AREA)
- Pharmaceuticals Containing Other Organic And Inorganic Compounds (AREA)
- Saccharide Compounds (AREA)
- Preparation Of Compounds By Using Micro-Organisms (AREA)
- Steroid Compounds (AREA)
- Heterocyclic Carbon Compounds Containing A Hetero Ring Having Oxygen Or Sulfur (AREA)
- Compounds Of Unknown Constitution (AREA)
Abstract
Description
Priority Applications (10)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US09/297,241 US6072052A (en) | 1996-10-31 | 1997-10-20 | Method for the production of ivermectin |
BR9712690-0A BR9712690A (pt) | 1996-10-31 | 1997-10-20 | Processo para a preparação de ivermectina |
AU50512/98A AU5051298A (en) | 1996-10-31 | 1997-10-20 | Method for the production of ivermectin |
DE59706904T DE59706904D1 (de) | 1996-10-31 | 1997-10-20 | Verfahren zur herstellung von ivermectin |
DK97913164T DK0937094T3 (da) | 1996-10-31 | 1997-10-20 | Fremgangsmåde til fremstilling af ivermectin |
CA002269943A CA2269943C (en) | 1996-10-31 | 1997-10-20 | Method for the production of ivermectin |
EP97913164A EP0937094B1 (de) | 1996-10-31 | 1997-10-20 | Verfahren zur herstellung von ivermectin |
AT97913164T ATE215552T1 (de) | 1996-10-31 | 1997-10-20 | Verfahren zur herstellung von ivermectin |
JP10519998A JP2001502716A (ja) | 1996-10-31 | 1997-10-20 | イベルメクチンの製造方法 |
HK00103878A HK1024485A1 (en) | 1996-10-31 | 2000-06-27 | Method for the production of ivermectin. |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE19644050.5 | 1996-10-31 | ||
DE19644050A DE19644050A1 (de) | 1996-10-31 | 1996-10-31 | Verfahren zur Herstellung von Ivermectin |
Publications (1)
Publication Number | Publication Date |
---|---|
WO1998018806A1 true WO1998018806A1 (de) | 1998-05-07 |
Family
ID=7809764
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/EP1997/005777 WO1998018806A1 (de) | 1996-10-31 | 1997-10-20 | Verfahren zur herstellung von ivermectin |
Country Status (16)
Country | Link |
---|---|
US (1) | US6072052A (de) |
EP (1) | EP0937094B1 (de) |
JP (1) | JP2001502716A (de) |
KR (1) | KR100468206B1 (de) |
CN (1) | CN1146572C (de) |
AT (1) | ATE215552T1 (de) |
AU (1) | AU5051298A (de) |
BR (1) | BR9712690A (de) |
CA (1) | CA2269943C (de) |
DE (2) | DE19644050A1 (de) |
DK (1) | DK0937094T3 (de) |
ES (1) | ES2175377T3 (de) |
HK (1) | HK1024485A1 (de) |
HU (1) | HUP9904497A3 (de) |
PT (1) | PT937094E (de) |
WO (1) | WO1998018806A1 (de) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6072052A (en) * | 1996-10-31 | 2000-06-06 | Bayer Aktiengesellschaft | Method for the production of ivermectin |
Families Citing this family (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN100396691C (zh) * | 2004-12-06 | 2008-06-25 | 四川大学 | 一种伊维菌素的制备方法 |
CN100486986C (zh) * | 2007-01-29 | 2009-05-13 | 四川大学 | 一种依维菌素的制备方法 |
PT117268B (pt) | 2021-06-01 | 2023-12-05 | Hovione Farm S A | Processo para controlar o tamanho de partícula e substâncias aparentadas da ivermectina com utilização de alto cisalhamento |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0001689A1 (de) * | 1977-10-03 | 1979-05-02 | Merck & Co. Inc. | Produkte der selektiven Hydrierung von C-076 Verbindungen, ihre Derivate, ihre Herstellung und Zusammensetzungen zur Behandlung von parasitären Infektionen, die diese Verbindungen enthalten |
EP0059616A1 (de) * | 1981-03-02 | 1982-09-08 | Merck & Co. Inc. | Verfahren zur Entfernung von Metallkatalysatoren aus Verfahrenslösungen |
EP0729971A1 (de) * | 1995-03-01 | 1996-09-04 | Bayer Ag | Verfahren zur Herstellung von Ivermectin |
Family Cites Families (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
PT74303B (fr) * | 1982-01-19 | 1983-08-08 | Joao Emerico Villax | Procede pour la preparation de nouveaux catalysateurs contenant rhodium et son utilisation |
US4500458A (en) * | 1982-01-19 | 1985-02-19 | Plurichemie Anstalt | Process for the preparation of α-6-deoxytetracyclines |
GB2114627B (en) * | 1982-02-09 | 1985-05-01 | Padley And Venables Limited | Mineral mining apparatus provided with dust suppressing means |
DE19644050A1 (de) * | 1996-10-31 | 1998-05-07 | Bayer Ag | Verfahren zur Herstellung von Ivermectin |
IT1289993B1 (it) * | 1997-02-27 | 1998-10-19 | Antibioticos Spa | Processo per la preparazione di ivermectina |
-
1996
- 1996-10-31 DE DE19644050A patent/DE19644050A1/de not_active Withdrawn
-
1997
- 1997-10-20 DE DE59706904T patent/DE59706904D1/de not_active Expired - Fee Related
- 1997-10-20 BR BR9712690-0A patent/BR9712690A/pt not_active IP Right Cessation
- 1997-10-20 ES ES97913164T patent/ES2175377T3/es not_active Expired - Lifetime
- 1997-10-20 AT AT97913164T patent/ATE215552T1/de not_active IP Right Cessation
- 1997-10-20 US US09/297,241 patent/US6072052A/en not_active Expired - Fee Related
- 1997-10-20 JP JP10519998A patent/JP2001502716A/ja not_active Ceased
- 1997-10-20 CN CNB97180494XA patent/CN1146572C/zh not_active Expired - Fee Related
- 1997-10-20 WO PCT/EP1997/005777 patent/WO1998018806A1/de active IP Right Grant
- 1997-10-20 PT PT97913164T patent/PT937094E/pt unknown
- 1997-10-20 KR KR10-1999-7003084A patent/KR100468206B1/ko not_active IP Right Cessation
- 1997-10-20 AU AU50512/98A patent/AU5051298A/en not_active Abandoned
- 1997-10-20 EP EP97913164A patent/EP0937094B1/de not_active Expired - Lifetime
- 1997-10-20 DK DK97913164T patent/DK0937094T3/da active
- 1997-10-20 CA CA002269943A patent/CA2269943C/en not_active Expired - Fee Related
- 1997-10-20 HU HU9904497A patent/HUP9904497A3/hu unknown
-
2000
- 2000-06-27 HK HK00103878A patent/HK1024485A1/xx not_active IP Right Cessation
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0001689A1 (de) * | 1977-10-03 | 1979-05-02 | Merck & Co. Inc. | Produkte der selektiven Hydrierung von C-076 Verbindungen, ihre Derivate, ihre Herstellung und Zusammensetzungen zur Behandlung von parasitären Infektionen, die diese Verbindungen enthalten |
EP0059616A1 (de) * | 1981-03-02 | 1982-09-08 | Merck & Co. Inc. | Verfahren zur Entfernung von Metallkatalysatoren aus Verfahrenslösungen |
EP0729971A1 (de) * | 1995-03-01 | 1996-09-04 | Bayer Ag | Verfahren zur Herstellung von Ivermectin |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6072052A (en) * | 1996-10-31 | 2000-06-06 | Bayer Aktiengesellschaft | Method for the production of ivermectin |
Also Published As
Publication number | Publication date |
---|---|
EP0937094B1 (de) | 2002-04-03 |
JP2001502716A (ja) | 2001-02-27 |
DK0937094T3 (da) | 2002-07-15 |
KR100468206B1 (ko) | 2005-01-26 |
BR9712690A (pt) | 1999-10-19 |
CA2269943A1 (en) | 1998-05-07 |
CN1146572C (zh) | 2004-04-21 |
ATE215552T1 (de) | 2002-04-15 |
CN1239965A (zh) | 1999-12-29 |
EP0937094A1 (de) | 1999-08-25 |
DE59706904D1 (de) | 2002-05-08 |
HUP9904497A2 (hu) | 2000-05-28 |
KR20000049018A (ko) | 2000-07-25 |
DE19644050A1 (de) | 1998-05-07 |
ES2175377T3 (es) | 2002-11-16 |
HUP9904497A3 (en) | 2000-11-28 |
PT937094E (pt) | 2002-09-30 |
CA2269943C (en) | 2006-12-12 |
US6072052A (en) | 2000-06-06 |
AU5051298A (en) | 1998-05-22 |
HK1024485A1 (en) | 2000-10-13 |
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