CA1179354A - Process for the preparation of 4-(3-methyl-2-butenyl)- 1, 2-diphenyl-3, 5-dioxopyrazolidine - Google Patents
Process for the preparation of 4-(3-methyl-2-butenyl)- 1, 2-diphenyl-3, 5-dioxopyrazolidineInfo
- Publication number
- CA1179354A CA1179354A CA000414428A CA414428A CA1179354A CA 1179354 A CA1179354 A CA 1179354A CA 000414428 A CA000414428 A CA 000414428A CA 414428 A CA414428 A CA 414428A CA 1179354 A CA1179354 A CA 1179354A
- Authority
- CA
- Canada
- Prior art keywords
- diphenyl
- methyl
- dioxopyrazolidine
- butenyl
- palladium
- 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
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D233/00—Heterocyclic compounds containing 1,3-diazole or hydrogenated 1,3-diazole rings, not condensed with other rings
- C07D233/54—Heterocyclic compounds containing 1,3-diazole or hydrogenated 1,3-diazole rings, not condensed with other rings having two double bonds between ring members or between ring members and non-ring members
- C07D233/66—Heterocyclic compounds containing 1,3-diazole or hydrogenated 1,3-diazole rings, not condensed with other rings having two double bonds between ring members or between ring members and non-ring members with hetero atoms or with carbon atoms having three bonds to hetero atoms with at the most one bond to halogen, e.g. ester or nitrile radicals, directly attached to ring carbon atoms
- C07D233/72—Two oxygen atoms, e.g. hydantoin
- C07D233/74—Two oxygen atoms, e.g. hydantoin with only hydrogen atoms or radicals containing only hydrogen and carbon atoms, attached to other ring members
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D231/00—Heterocyclic compounds containing 1,2-diazole or hydrogenated 1,2-diazole rings
- C07D231/02—Heterocyclic compounds containing 1,2-diazole or hydrogenated 1,2-diazole rings not condensed with other rings
- C07D231/10—Heterocyclic compounds containing 1,2-diazole or hydrogenated 1,2-diazole rings not condensed with other rings having two or three double bonds between ring members or between ring members and non-ring members
- C07D231/14—Heterocyclic compounds containing 1,2-diazole or hydrogenated 1,2-diazole rings not condensed with other rings having two or three double bonds between ring members or between ring members and non-ring members with hetero atoms or with carbon atoms having three bonds to hetero atoms with at the most one bond to halogen, e.g. ester or nitrile radicals, directly attached to ring carbon atoms
- C07D231/28—Two oxygen or sulfur atoms
- C07D231/30—Two oxygen or sulfur atoms attached in positions 3 and 5
- C07D231/32—Oxygen atoms
- C07D231/34—Oxygen atoms with only hydrogen atoms or radicals containing only hydrogen and carbon atoms, attached in position 4
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61P—SPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS OR MEDICINAL PREPARATIONS
- A61P29/00—Non-central analgesic, antipyretic or antiinflammatory agents, e.g. antirheumatic agents; Non-steroidal antiinflammatory drugs [NSAID]
Abstract
ABSTRACT OF THE DISCLOSURE
New process for the preparation of 4-(3-methyl-2-butenyl)-1,2-diphenyl-3,5-dioxopyrazolidine (Feprazone)
New process for the preparation of 4-(3-methyl-2-butenyl)-1,2-diphenyl-3,5-dioxopyrazolidine (Feprazone)
Description
3~
Process for the Preparation of 4-(3-methYl-2-butenyl)-1,2-diphenyl-3,5-dioxoPyrazolidlne The pres~nt invention relates to a novel process for the preparation of 4-(3-methyl-2-butenyl)-1,2-diphenyl-3,5-dioxopyrazolidine.
British Patent No. 1,301,857 describes two deriva-tives of 1,2-diphenyl-3,5-dioxopyrazolidine and processes for their preparation. One of these two derivatives is 4-(3-methyl-2-butenyl)-1,2-diphenyl-3,5-dioxopyra~
zolidine (Feprazone) a valuable analgesic-antinflammatory drug c~rrently used in the treatment of rheumatic and arthritic conditions, and, in general, in the management of inflammatory diseases.
Am~ng the methods for the preparation of this compound, the reac~ion of 1,2-diphenyl-3,5-dioxopyrazol-idine or of one of its alkali metal salts with a halide, i.e. 3-methyl-2-butenyl chloride or bromide, is described.
This reaction is essentially a nucleophilic displacement between the anion of 1,2-diphenyl-3,5~dioxopyrazolidine, whicb possesses an active methylene group, and the active allylic halide, for example 3-methyl-2-butenyl chloride, CH3 CH3 \ /
\ C/ C~ C
OC / base CH
Process for the Preparation of 4-(3-methYl-2-butenyl)-1,2-diphenyl-3,5-dioxoPyrazolidlne The pres~nt invention relates to a novel process for the preparation of 4-(3-methyl-2-butenyl)-1,2-diphenyl-3,5-dioxopyrazolidine.
British Patent No. 1,301,857 describes two deriva-tives of 1,2-diphenyl-3,5-dioxopyrazolidine and processes for their preparation. One of these two derivatives is 4-(3-methyl-2-butenyl)-1,2-diphenyl-3,5-dioxopyra~
zolidine (Feprazone) a valuable analgesic-antinflammatory drug c~rrently used in the treatment of rheumatic and arthritic conditions, and, in general, in the management of inflammatory diseases.
Am~ng the methods for the preparation of this compound, the reac~ion of 1,2-diphenyl-3,5-dioxopyrazol-idine or of one of its alkali metal salts with a halide, i.e. 3-methyl-2-butenyl chloride or bromide, is described.
This reaction is essentially a nucleophilic displacement between the anion of 1,2-diphenyl-3,5~dioxopyrazolidine, whicb possesses an active methylene group, and the active allylic halide, for example 3-methyl-2-butenyl chloride, CH3 CH3 \ /
\ C/ C~ C
OC / base CH
2 ~ >~ Cl H2 X OC ~CO
N--N
( X = h a l og e n a t o m ) ~ g~`',t .... . . ... . .
1~793~
An object of the present invention is to provide a new process for the preparation of 4-(3-methyl-2-butenyl)-1,2-diphenyl-3,5-dioxopyrazolidine.
Thus, we provide a process for the preparation of 4-(3-methyl-2-bu~enyl)-1,2-diphenyl-3,5-dioxopyrazol-idine of formula CH3\ C0 \ /
CH3 C0 ~ \
\J
which comprises reacting 3-methyl-2-butenyl acetate with an alkali metal salt of 1,2-diphenyl-3,5-dioxo~
pyrazolidine in the presence of a suitable catalyst and of a ligand.
Preferred catalysts are palladium complexes, and the process may be represented as follows:
C ~ C H3 C ~ CH3 C M C
Il . CH CH
CH OC / Pd()cc~pl~ CH
CH2 N--N ll~and, I
~ \ sc?lvent O ~ 9 C H
CO OC O
N--N
ctl3 @~< \~
(M ~ alkali metal ) One of the main advantages of the invention is that 3-methyl-2-butenyl acetate, unlike the 3-methyl-2-butenyl halide~, is a stable and manageable substance.
~7~35~
It can be obtained from isoprene, acetic acid, and acetic anhydride in the pres-ence of a suitable catalyst, according to Belgian Patent No. 640,309. Further-more, other advantages are the selectivity of C vs. o alkylation and the minimiz-ation of the elimination reaction.
More particularly, the new process according to the present invention comprises reacting 3-methyl-2-butenyl acetate with an alkali metal salt (such as the sodium, potassium or lithium salt, advantageously the lithium salt) of 1,2-diphenyl-3,5-dioxopyrazolidine in the presence of a palladium-complex catalyst.
Preferred catalys-ts are tetrakis-(triphenylphosphine) palladium (O) [(Ph3P)4Pd( )], bis-(dibenzylideneacetone) palladium (O) [(dba)2Pd()] and bis [1,2-bis-(diphenyl-phosphino)-ethane] palladium (O), [(DIPHOS)2Pd( )], conveniently tetrakis (triphe-nylphosphine) palladium tO) in the presence of ligands such as, for example, tri-phenylphosphine (TPP), 1,2-bis-(diphenylphosphino)-ethane (DIPHOS) or hexamethyl-phosphorustriamide (HMP), preEerably triphenylphosphine. Solvents preferably used in the reaction are inert organic or ethereal solvents such as, for example, te-trahydrofuran, 1,2-dimethoxyethane, and dimethylsulfoxide, advantageously tetra-hydrofuran under anhydrous conditions.
The reaction is conveniently performed by mixing a-t room temperature 3-methyl-2-butenyl acetate dissolved in the appropriate solvent, e.g. te-trahydro-furan, with the palladium complex and -the proper ligand. SatisEactory quantities of catalyst rancJe Erom 0.1 to 10 mol ~. The solution of the alkali metal salt oE
1,2-~:iph~nyl-3,5-dloxopyrazolidine (2 to ~ moles) is then added rapidly and the mixture ls stirred at a temperature ranging from room -tempera-ture (20C) -to 70C.
Subsequently the reaction mixtuxe is poured into aci~ic water (pH ~ to 5) and extractecl with a suitable solvent, Eor example e-thyl acetate, ethyl ether or dichloromethane. The product obtained after evaporation of the solvent is purified; either directly by column chromatography or by re-extracting with a basic aqueous medium. In ~he latter case the product is isolated after acidifying with a mineral acid, preferably hydrochloric acid, and extracting with a suitable solvent.
Additional purification may be achieved by column chromatography.
The following non-limiting examples serve to illustrate the present invention:
N--N
( X = h a l og e n a t o m ) ~ g~`',t .... . . ... . .
1~793~
An object of the present invention is to provide a new process for the preparation of 4-(3-methyl-2-butenyl)-1,2-diphenyl-3,5-dioxopyrazolidine.
Thus, we provide a process for the preparation of 4-(3-methyl-2-bu~enyl)-1,2-diphenyl-3,5-dioxopyrazol-idine of formula CH3\ C0 \ /
CH3 C0 ~ \
\J
which comprises reacting 3-methyl-2-butenyl acetate with an alkali metal salt of 1,2-diphenyl-3,5-dioxo~
pyrazolidine in the presence of a suitable catalyst and of a ligand.
Preferred catalysts are palladium complexes, and the process may be represented as follows:
C ~ C H3 C ~ CH3 C M C
Il . CH CH
CH OC / Pd()cc~pl~ CH
CH2 N--N ll~and, I
~ \ sc?lvent O ~ 9 C H
CO OC O
N--N
ctl3 @~< \~
(M ~ alkali metal ) One of the main advantages of the invention is that 3-methyl-2-butenyl acetate, unlike the 3-methyl-2-butenyl halide~, is a stable and manageable substance.
~7~35~
It can be obtained from isoprene, acetic acid, and acetic anhydride in the pres-ence of a suitable catalyst, according to Belgian Patent No. 640,309. Further-more, other advantages are the selectivity of C vs. o alkylation and the minimiz-ation of the elimination reaction.
More particularly, the new process according to the present invention comprises reacting 3-methyl-2-butenyl acetate with an alkali metal salt (such as the sodium, potassium or lithium salt, advantageously the lithium salt) of 1,2-diphenyl-3,5-dioxopyrazolidine in the presence of a palladium-complex catalyst.
Preferred catalys-ts are tetrakis-(triphenylphosphine) palladium (O) [(Ph3P)4Pd( )], bis-(dibenzylideneacetone) palladium (O) [(dba)2Pd()] and bis [1,2-bis-(diphenyl-phosphino)-ethane] palladium (O), [(DIPHOS)2Pd( )], conveniently tetrakis (triphe-nylphosphine) palladium tO) in the presence of ligands such as, for example, tri-phenylphosphine (TPP), 1,2-bis-(diphenylphosphino)-ethane (DIPHOS) or hexamethyl-phosphorustriamide (HMP), preEerably triphenylphosphine. Solvents preferably used in the reaction are inert organic or ethereal solvents such as, for example, te-trahydrofuran, 1,2-dimethoxyethane, and dimethylsulfoxide, advantageously tetra-hydrofuran under anhydrous conditions.
The reaction is conveniently performed by mixing a-t room temperature 3-methyl-2-butenyl acetate dissolved in the appropriate solvent, e.g. te-trahydro-furan, with the palladium complex and -the proper ligand. SatisEactory quantities of catalyst rancJe Erom 0.1 to 10 mol ~. The solution of the alkali metal salt oE
1,2-~:iph~nyl-3,5-dloxopyrazolidine (2 to ~ moles) is then added rapidly and the mixture ls stirred at a temperature ranging from room -tempera-ture (20C) -to 70C.
Subsequently the reaction mixtuxe is poured into aci~ic water (pH ~ to 5) and extractecl with a suitable solvent, Eor example e-thyl acetate, ethyl ether or dichloromethane. The product obtained after evaporation of the solvent is purified; either directly by column chromatography or by re-extracting with a basic aqueous medium. In ~he latter case the product is isolated after acidifying with a mineral acid, preferably hydrochloric acid, and extracting with a suitable solvent.
Additional purification may be achieved by column chromatography.
The following non-limiting examples serve to illustrate the present invention:
3-Methyl-2-butenyl acetate (5g, 0.039 mol), triphenyl-phosphine tO.93g) and tetrakis-(triphenylphosphine) palladium ~O) ~1.42 9, 0.00123 mol) in 75ml of dry tetrahydrofuran were stirred for 15 min. at room temper-ature. A solution of the lithium salt of 1,2-diphenyl-3,5-dioxopyrazolidine (20.13g, 0.078 mol) diss~lved in 200ml of anhydrous tetrahydrofuran was then added all at once and the resultant mixture refluxed (15 hr) under nitrogen. The reaction solution was concentrat-ed and then poured into excess water. After acid-ification to pH 4-5 the aqueous solution was extracted with methylene chloride. The organic layer was separated, dried (Mg SO4), and evaporated to dryness to afford the title compound as a crude product. Purification by column chromatography (Silica gel) (CH2C12 / CH3CN
98:2 v/v) furnished the desired compound in a pure form.
M.p. 156C~
Analysis 0 for C20H~oN202 : found% C 75.14; H 6.37; N 8.68-calc 4 C 74.79; ~ 6.29; ~ 8.74.
~MPLE 2 3-~ethyl-2-butenyl acetate (5g, 0.039 mol),1,2-bls-(diph~nyl-phosphino)-ethane (0.155 g, 0.39 mmol), and bis-(dibenzyl-ideneacetone) palladium (O) ~0.3g, 0.522 mmol) in75ml of anhydrous tetrahydrofuran were stirr~d for 10 min. at room temperature. A solution of the lithium salt o~ 1,2-diphenyl 3,5-dioxopyrazolidine (20.139, ~93~L
0.078 mol) in 150 ml) of anhydrous tetrahydrofuran was then added at once and the resultant mixture stirred (48 hr) at room temperature. Then proceeding as described in example 1, the desired compound was obtained.
5 M.p. 156 CJ
Analysis for C20H20N2O2 : found % C 74.85; H 6-11; N 8-81-calc ~ C 74.97; H 6.29; N 8.74.
98:2 v/v) furnished the desired compound in a pure form.
M.p. 156C~
Analysis 0 for C20H~oN202 : found% C 75.14; H 6.37; N 8.68-calc 4 C 74.79; ~ 6.29; ~ 8.74.
~MPLE 2 3-~ethyl-2-butenyl acetate (5g, 0.039 mol),1,2-bls-(diph~nyl-phosphino)-ethane (0.155 g, 0.39 mmol), and bis-(dibenzyl-ideneacetone) palladium (O) ~0.3g, 0.522 mmol) in75ml of anhydrous tetrahydrofuran were stirr~d for 10 min. at room temperature. A solution of the lithium salt o~ 1,2-diphenyl 3,5-dioxopyrazolidine (20.139, ~93~L
0.078 mol) in 150 ml) of anhydrous tetrahydrofuran was then added at once and the resultant mixture stirred (48 hr) at room temperature. Then proceeding as described in example 1, the desired compound was obtained.
5 M.p. 156 CJ
Analysis for C20H20N2O2 : found % C 74.85; H 6-11; N 8-81-calc ~ C 74.97; H 6.29; N 8.74.
Claims (8)
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. Process for the preparation of 4-(3-methyl-2-butenyl)-1,2-diphenyl-3,5-dioxopyrazolidine of formula which comprises reacting 3-methyl-2-butenyl acetate with an alkali metal salt of 1,2-diphenyl-3,5-dioxopyrazolidine in the presence of a suitable catalyst and of a ligand.
2. A process as claimed in claim 1, wherein the sodium, potassium or lith-ium salt of 1,2-diphenyl-3,5-dioxopyrazolidine is employed.
3. A process as claimed in claim 1, wherein the catalyst is a palladium complex.
4. A process as claimed in claim 1, 2 or 3, wherein the catalyst is tetra-kis (triphenylphosphine) palladium (O), bis-(dibenzylideneacetone) palladium (O) or bis-[1,2-bis-(diphenylphosphino)-ethane] palladium (O).
5. A process as claimed in claim 1, 2 or 3, wherein the ligand is triphe-nylphosphine, 1,2-bis (diphenylphosphino)-ethane or hexamethylphosphorustriamide.
6. A process as claimed in claim 1, 2 or 3, wherein the reaction is carr-ied out in the presence of an inert organic solvent.
7. A process as claimed in claim 1, 2 or 3, wherein the reaction is carr-ied out in the presence of an inert organic solvent and the inert organic solvent comprises tetrahydrofuran, 1,2-dimethoxyethane or dimethylsulfoxide.
8. A process as claimed in claim 1, 2 or 3, wherein the reaction is carr-ied out at a temperature of from 20 to 70°C.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| IT24772/81A IT1168184B (en) | 1981-10-29 | 1981-10-29 | PROCESS FOR THE PREPARATION OF 4- (3-METHYL-2-BUTANYL) -1,2-DIPHENYL-3,5 DICHETOPYRAZOLIDINE |
| IT24772A/81 | 1981-10-29 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1179354A true CA1179354A (en) | 1984-12-11 |
Family
ID=11214682
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000414428A Expired CA1179354A (en) | 1981-10-29 | 1982-10-28 | Process for the preparation of 4-(3-methyl-2-butenyl)- 1, 2-diphenyl-3, 5-dioxopyrazolidine |
Country Status (19)
| Country | Link |
|---|---|
| JP (1) | JPS5888365A (en) |
| KR (1) | KR840001955A (en) |
| AR (1) | AR231832A1 (en) |
| AT (1) | AT379151B (en) |
| CA (1) | CA1179354A (en) |
| CH (1) | CH651555A5 (en) |
| DK (1) | DK477882A (en) |
| ES (1) | ES516902A0 (en) |
| FI (1) | FI823545L (en) |
| FR (1) | FR2515646B1 (en) |
| GB (1) | GB2108125B (en) |
| GR (1) | GR77724B (en) |
| IT (1) | IT1168184B (en) |
| NL (1) | NL8204170A (en) |
| NO (1) | NO823596L (en) |
| PH (1) | PH19644A (en) |
| PT (1) | PT75755B (en) |
| SE (1) | SE8206143L (en) |
| YU (1) | YU240282A (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107778247A (en) * | 2016-08-30 | 2018-03-09 | 天津太平洋制药有限公司 | A kind of preparation method of feprazone and its intermediate |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1301857A (en) * | 1969-06-27 | 1973-01-04 |
-
1981
- 1981-10-29 IT IT24772/81A patent/IT1168184B/en active
-
1982
- 1982-10-07 AT AT0370382A patent/AT379151B/en not_active IP Right Cessation
- 1982-10-14 PH PH27984A patent/PH19644A/en unknown
- 1982-10-18 FI FI823545A patent/FI823545L/en not_active Application Discontinuation
- 1982-10-26 YU YU02402/82A patent/YU240282A/en unknown
- 1982-10-26 CH CH6249/82A patent/CH651555A5/en not_active IP Right Cessation
- 1982-10-26 GR GR69645A patent/GR77724B/el unknown
- 1982-10-27 PT PT75755A patent/PT75755B/en unknown
- 1982-10-28 CA CA000414428A patent/CA1179354A/en not_active Expired
- 1982-10-28 GB GB08230767A patent/GB2108125B/en not_active Expired
- 1982-10-28 KR KR1019820004867A patent/KR840001955A/en unknown
- 1982-10-28 SE SE8206143A patent/SE8206143L/en not_active Application Discontinuation
- 1982-10-28 NO NO823596A patent/NO823596L/en unknown
- 1982-10-28 NL NL8204170A patent/NL8204170A/en not_active Application Discontinuation
- 1982-10-28 DK DK477882A patent/DK477882A/en not_active Application Discontinuation
- 1982-10-28 ES ES516902A patent/ES516902A0/en active Granted
- 1982-10-28 JP JP57189954A patent/JPS5888365A/en active Pending
- 1982-10-29 FR FR8218200A patent/FR2515646B1/en not_active Expired
- 1982-10-29 AR AR291152A patent/AR231832A1/en active
Also Published As
| Publication number | Publication date |
|---|---|
| AR231832A1 (en) | 1985-03-29 |
| PT75755B (en) | 1985-11-20 |
| YU240282A (en) | 1985-03-20 |
| GB2108125A (en) | 1983-05-11 |
| IT8124772A0 (en) | 1981-10-29 |
| IT1168184B (en) | 1987-05-20 |
| ES8308855A1 (en) | 1983-10-01 |
| PH19644A (en) | 1986-06-04 |
| AT379151B (en) | 1985-11-25 |
| CH651555A5 (en) | 1985-09-30 |
| NL8204170A (en) | 1983-05-16 |
| SE8206143L (en) | 1983-04-30 |
| JPS5888365A (en) | 1983-05-26 |
| KR840001955A (en) | 1984-06-07 |
| FI823545L (en) | 1983-04-30 |
| SE8206143D0 (en) | 1982-10-28 |
| DK477882A (en) | 1983-04-30 |
| PT75755A (en) | 1982-11-01 |
| ES516902A0 (en) | 1983-10-01 |
| GB2108125B (en) | 1985-03-20 |
| FR2515646A1 (en) | 1983-05-06 |
| GR77724B (en) | 1984-09-25 |
| FI823545A0 (en) | 1982-10-18 |
| FR2515646B1 (en) | 1986-02-14 |
| ATA370382A (en) | 1985-04-15 |
| NO823596L (en) | 1983-05-02 |
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