CN109761809A - A kind of method of the palladium carbon catalysis bromo- 2- of reduction synthesis 2- (the fluoro- 3- methoxyphenyl of 2-) ethyl acetate - Google Patents
A kind of method of the palladium carbon catalysis bromo- 2- of reduction synthesis 2- (the fluoro- 3- methoxyphenyl of 2-) ethyl acetate Download PDFInfo
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- CN109761809A CN109761809A CN201910118477.2A CN201910118477A CN109761809A CN 109761809 A CN109761809 A CN 109761809A CN 201910118477 A CN201910118477 A CN 201910118477A CN 109761809 A CN109761809 A CN 109761809A
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Abstract
The invention discloses a kind of method of palladium carbon catalysis bromo- 2- of reduction synthesis 2- (the fluoro- 3- methoxyphenyl of 2-) ethyl acetate, synthetic route is as follows:
Description
Technical field
The present invention relates to machine synthesis and medicine intermediate technical field, specifically a kind of palladium carbon catalysis reduction synthesis 2- is bromo-
The synthetic method of the method for 2- (the fluoro- 3- methoxyphenyl of 2-) ethyl acetate.
Background technique
Pain caused by Eagolix conduct is treated because of endometriosis, structure are as follows:
The bromo- 2- of 2- (the fluoro- 3- methoxyphenyl of 2-) ethyl acetate, structure is as shown in formula I, in the prior art by the chemical combination
Object is used for the synthesis of eagolix bulk pharmaceutical chemicals.
Patent No.: WO2009062087 discloses the synthetic method about the compound, and synthetic route is as follows:
The patent document is using adjacent fluorine methoxyl group benzene as starting material, after lithiumation, addition, reduction, Mesylation, bromo etc.
Multistep reaction obtains finally such as I compound represented of formula.
But the synthetic route step is more, is in particular in: in synthetic route, above-mentioned process route passes through hydroboration
Sodium by the carbonyl reduction on benzene ring side chain at hydroxyl after, then hydroxyl is transformed by easy leaving group by Mesylation, finally led to
The mode for crossing bromination substitution, introduces bromine atom on former hydroxyl position.The defect of said synthesis route is going back for carbonyl
As far as between the introducing of bromine atom, reaction step is excessively many and diverse, and overall yield is caused to reduce.
Summary of the invention
Technical problem to be solved by the present invention lies in: a kind of palladium carbon catalysis bromo- 2- of reduction synthesis 2- (fluoro- 3- of 2- is provided
Methoxyphenyl) ethyl acetate method, to solve the technological deficiency that existing synthetic route yield is low, pollution is big, step is long.
The present invention is to solve above-mentioned technical problem by the following technical programs:
A kind of method of the palladium carbon catalysis bromo- 2- of reduction synthesis 2- (the fluoro- 3- methoxyphenyl of 2-) ethyl acetate, synthetic route
It is as follows:
The method of the above-mentioned palladium carbon catalysis bromo- 2- of reduction synthesis 2- (the fluoro- 3- methoxyphenyl of 2-) ethyl acetate includes following
Step:
The preparation of S1, V compound of formula: the Formula II compound of 0.5-1.5g, 1.0equiv. are added into reactor, with
Formula II compound meter, successively by the sodium bicarbonate of 2.5-3.5equiv., hypophosphorous acid solution, the 0.05- of 3.5-4.5equiv.
The palladium carbon of 0.15equiv. is added into reactor, and the cyclopentyl-methyl ether of 2-6mL and the water of 6-12mL is added, stirs and evenly mixs,
It is warming up to reflux, after back flow reaction 18-22h, reaction system is cooled to room temperature, reaction solution filtering, and filtrate is concentrated to dryness, concentrate
It extracts, distribute in methylene chloride and 0.5-1.5N aqueous hydrochloric acid solution, separate organic phase, organic phase successively uses saturated sodium bicarbonate
Aqueous solution and saturated common salt water washing, then with sodium sulphate drying and be spin-dried for, most V compound of formula is obtained through column chromatography for separation afterwards；
The preparation of S2, type I compound:
0.5-1.5g is weighed, for V compound of formula of 1.0equiv. in reactor, the carbon tetrachloride of 5-15mL dissolves dispersion
Afterwards, successively into reaction system, in terms of V compound of formula, the bromating agent and 0.1-0.15equiv. of 1.2-1.4equiv. is added
Initiator, after temperature rising reflux 4.5-5.5h, reaction solution is concentrated to dryness, and the residue being concentrated to get obtains after column chromatography for separation
Type I compound.
Preferably, the mass fraction of hypophosphorous acid solution is 50% in the step S1.
Preferably, the palladium carbon that palladium carbon is 5% in the step S1.
Preferably, by 1.0g in the step S1, the Formula II compound of 1.0equiv. is added into reactor, with Formula II
Successively the palladium carbon of the sodium bicarbonate of 3.0equiv., the hypophosphorous acid solution of 4.0equiv., 0.1equiv. are added for compound meter
Into reactor, the cyclopentyl-methyl ether of 4mL and the water of 10mL is added, stirs and evenly mixs, is warming up to reflux, after back flow reaction 20h,
Reaction system is cooled to room temperature, reaction solution filtering, and filtrate is concentrated to dryness, and concentrate extracts in methylene chloride and 1N aqueous hydrochloric acid solution
It takes, distribute.
The preparation of S2, type I compound:
Preferably, 1.0g is weighed in the step S2, V compound of formula of 1.0equiv. is in reactor, and the four of 10mL
Chlorination carbon dissolution dispersion after, successively into reaction system, in terms of V compound of formula, be added 1.2equiv. bromating agent and
0.1equiv. initiator, after temperature rising reflux 4.5h, reaction solution is concentrated to dryness, the residue being concentrated to get, after column chromatography for separation
Obtain type I compound.
Preferably, the bromating agent is one of NBS, C5H6Br2N2O2.
Preferably, the bromating agent is NBS.
Preferably, the initiator is one of benzoyl peroxide, AIBN.
Preferably, the initiator is benzoyl peroxide.
The present invention has the advantage that compared with prior art
The present invention discloses a kind of catalysis of the palladium carbon as shown in the formula I bromo- 2- of reduction synthesis 2- (the fluoro- 3- methoxyphenyl of 2-) second
The method of acetoacetic ester, compare with traditional synthetic route, process route disclosed by the invention, not only on synthesis material it is cheap easily
, and synthetic route is environmentally protective, such as avoids using mesyl chloride, it is easy to operate.
Specific embodiment
It elaborates below to the embodiment of the present invention, the present embodiment carries out under the premise of the technical scheme of the present invention
Implement, the detailed implementation method and specific operation process are given, but protection scope of the present invention is not limited to following implementation
Example.
Embodiment 1
A kind of method of the palladium carbon catalysis bromo- 2- of reduction synthesis 2- (the fluoro- 3- methoxyphenyl of 2-) ethyl acetate, synthetic route
It is as follows:
The method of the above-mentioned palladium carbon catalysis bromo- 2- of reduction synthesis 2- (the fluoro- 3- methoxyphenyl of 2-) ethyl acetate includes following
Step:
S1, by 1.0g, the Formula II compound of 1.0equiv. is added into reactor, in terms of Formula II compound, successively will
Sodium bicarbonate, the 4.0equiv. of 3.0equiv., hypophosphorous acid solution (the secondary phosphorus that mass fraction is 40% that mass fraction is 50%
Aqueous acid), 0.1equiv., 5% palladium carbon is added into reactor, the cyclopentyl-methyl ether of 4mL and the water of 8mL is added, stirs
Mixing is mixed, is warming up to reflux, after back flow reaction 20h, reaction system is cooled to room temperature, and reaction solution filtering, filtrate is concentrated to dryness, dense
Contracting object is extracted in methylene chloride and 1N aqueous hydrochloric acid solution, is distributed, and separates organic phase, and organic phase successively uses saturated sodium bicarbonate water
Solution and saturated common salt water washing, then with sodium sulphate drying and be spin-dried for, most V compound of formula, yield are obtained through column chromatography for separation afterwards
50%, high resolution mass spectrum (ESI+): C11H14FO3 +, 213.0928；
The preparation of S2, type I compound:
1.0g is weighed, V compound of formula of 1.0equiv. is in reactor, after the carbon tetrachloride dissolution dispersion of 10mL, according to
It is secondary that in terms of V compound of formula, NBS the and 0.1equiv. benzoyl peroxide of 1.2equiv. is added into reaction system, heating
It flows back after 4.5h, reaction solution is concentrated to dryness, and the residue being concentrated to get obtains type I compound, yield after column chromatography for separation
63%, high resolution mass spectrum (ESI+): C11H13BrFO3 +, 291.0035.
Embodiment 2
A kind of method of the palladium carbon catalysis bromo- 2- of reduction synthesis 2- (the fluoro- 3- methoxyphenyl of 2-) ethyl acetate, synthetic route
It is as follows:
The method of the above-mentioned palladium carbon catalysis bromo- 2- of reduction synthesis 2- (the fluoro- 3- methoxyphenyl of 2-) ethyl acetate includes following
Step:
The preparation of S1, V compound of formula: the Formula II compound of 0.5g, 1.0equiv. are added into reactor, with Formula II
Compound meter, successively by the sodium bicarbonate of 2.5equiv., 3.5equiv., hypophosphorous acid solution that mass fraction is 50%,
0.15equiv., 5% palladium carbon are added into reactor, and the cyclopentyl-methyl ether of 6mL and the water of 12mL is added, stirs and evenly mixs,
It is warming up to reflux, after back flow reaction 22h, reaction system is cooled to room temperature, reaction solution filtering, and filtrate is concentrated to dryness, and concentrate exists
It extracts, distribute in methylene chloride and 1.5N aqueous hydrochloric acid solution, separate organic phase, organic phase successively uses saturated sodium bicarbonate aqueous solution
It is then dry with sodium sulphate and be spin-dried for saturated common salt water washing, most V compound of formula, yield are obtained through column chromatography for separation afterwards
49.8%, high resolution mass spectrum (ESI+): C11H14FO3 +, 213.0928；
The preparation of S2, type I compound:
0.5g is weighed, V compound of formula of 1.0equiv. is in reactor, after the carbon tetrachloride dissolution dispersion of 5mL, successively
Into reaction system, in terms of V compound of formula, the C5H6Br2N2O2 and 0.1equiv. benzoyl peroxide of 1.2equiv. is added, rises
After temperature reflux 5.5h, reaction solution is concentrated to dryness, and the residue being concentrated to get obtains type I compound, yield after column chromatography for separation
62.4%, high resolution mass spectrum (ESI+): C11H13BrFO3 +, 291.0035；
Embodiment 3
A kind of method of the palladium carbon catalysis bromo- 2- of reduction synthesis 2- (the fluoro- 3- methoxyphenyl of 2-) ethyl acetate, synthetic route
It is as follows:
The method of the above-mentioned palladium carbon catalysis bromo- 2- of reduction synthesis 2- (the fluoro- 3- methoxyphenyl of 2-) ethyl acetate includes following
Step:
The preparation of S1, V compound of formula: the Formula II compound of 1.5g, 1.0equiv. are added into reactor, with Formula II
Successively the palladium carbon of the sodium bicarbonate of 3.5equiv., the hypophosphorous acid solution of 4.5equiv., 0.15equiv. are added for compound meter
Into reactor, the cyclopentyl-methyl ether of 4mL and the water of 10mL is added, stirs and evenly mixs, is warming up to reflux, after back flow reaction 22h,
Reaction system is cooled to room temperature, reaction solution filtering, and filtrate is concentrated to dryness, and concentrate is in methylene chloride and 1.5N aqueous hydrochloric acid solution
Extraction, distribution, separate organic phase, organic phase successively uses saturated sodium bicarbonate aqueous solution and saturated common salt water washing, then uses sulfuric acid
Sodium is dry to be simultaneously spin-dried for, and most obtains V compound of formula through column chromatography for separation afterwards, yield 49.1%, high resolution mass spectrum (ESI+):
C11H14FO3 +, 213.0928；
The preparation of S2, type I compound:
1.5g is weighed, V compound of formula of 1.0equiv. is in reactor, after the carbon tetrachloride dissolution dispersion of 15mL, according to
It is secondary that in terms of V compound of formula, NBS the and 0.1equiv. benzoyl peroxide of 1.4equiv. is added into reaction system, heating
It flows back after 5.5h, reaction solution is concentrated to dryness, and the residue being concentrated to get obtains type I compound, yield after column chromatography for separation
60.5%, high resolution mass spectrum (ESI+): C11H13BrFO3 +, 291.0035.
Embodiment 4
A kind of method of the palladium carbon catalysis bromo- 2- of reduction synthesis 2- (the fluoro- 3- methoxyphenyl of 2-) ethyl acetate, synthetic route
It is as follows:
The method of the above-mentioned palladium carbon catalysis bromo- 2- of reduction synthesis 2- (the fluoro- 3- methoxyphenyl of 2-) ethyl acetate includes following
Step:
The preparation of S1, V compound of formula: the Formula II compound of 1.2g, 1.0equiv. are added into reactor, with Formula II
Successively the palladium carbon of the sodium bicarbonate of 2.8equiv., the hypophosphorous acid solution of 3.5equiv., 0.12equiv. are added for compound meter
Into reactor, the cyclopentyl-methyl ether of 5mL and the water of 8mL is added, stirs and evenly mixs, is warming up to reflux, after back flow reaction 19h,
Reaction system is cooled to room temperature, reaction solution filtering, and filtrate is concentrated to dryness, and concentrate is in methylene chloride and 0.8N aqueous hydrochloric acid solution
Extraction, distribution, separate organic phase, organic phase successively uses saturated sodium bicarbonate aqueous solution and saturated common salt water washing, then uses sulfuric acid
Sodium is dry to be simultaneously spin-dried for, and most obtains V compound of formula through column chromatography for separation afterwards, yield 48.3%, high resolution mass spectrum (ESI+):
C11H14FO3 +, 213.0928；
The preparation of S2, type I compound:
1.2g is weighed, V compound of formula of 1.0equiv. is in reactor, after the carbon tetrachloride dissolution dispersion of 12mL, according to
It is secondary that in terms of V compound of formula, NBS the and 0.1equiv. benzoyl peroxide of 1.3equiv. is added into reaction system, heating
It flows back after 4.8h, reaction solution is concentrated to dryness, and the residue being concentrated to get obtains type I compound, yield after column chromatography for separation
62.5%, high resolution mass spectrum (ESI+): C11H13BrFO3 +, 291.0035.
Embodiment 5
In the preparation process of V compound of formula, reaction condition is affected to reaction effect, preferably anti-in order to filter out
Condition is answered, according to technical solution disclosed in embodiment 1 (reaction condition is variable), finally screens preferable experiment as shown in Table 1
Parameter:
Table 1
The data disclosed in table 1: using 5% Pd/C as reducing agent, cyclopentyl-methyl ether: water=1:2 (volume
Than), when reacting 18h, reaction condition is preferable.
Embodiment 6
In the preparation process of compound shown in formula 1, the reaction conditions such as bromating agent, initiator and solvent, to reaction effect
It is affected, in order to filter out preferable reaction condition, according to technical solution disclosed in embodiment 1 (reaction condition is variable),
Finally screen preferable experiment parameter as shown in Table 2:
Table 2
The data disclosed in table 2: NBS is as bromating agent, and benzoyl peroxide is as initiator and carbon tetrachloride
As solvent, reaction effect is preferable.
The foregoing is merely illustrative of the preferred embodiments of the present invention, is not intended to limit the invention, all in essence of the invention
Made any modifications, equivalent replacements, and improvements etc., should all be included in the protection scope of the present invention within mind and principle.
Claims (9)
1. a kind of method of the palladium carbon catalysis bromo- 2- of reduction synthesis 2- (the fluoro- 3- methoxyphenyl of 2-) ethyl acetate, feature exist
In synthetic route is as follows:
2. the palladium carbon catalysis bromo- 2- of reduction synthesis 2- (the fluoro- 3- methoxyphenyl of 2-) ethyl acetate according to claim 1
Method, which comprises the following steps:
The preparation of S1, V compound of formula: the Formula II compound of 0.5-1.5g, 1.0equiv. are added into reactor, with Formula II
Compound meter, successively by the sodium bicarbonate of 2.5-3.5equiv., hypophosphorous acid solution, the 0.05- of 3.5-4.5equiv.
The palladium carbon of 0.15equiv. is added into reactor, and the cyclopentyl-methyl ether of 2-6mL and the water of 6-12mL is added, stirs and evenly mixs,
It is warming up to reflux, after back flow reaction 18-22h, reaction system is cooled to room temperature, reaction solution filtering, and filtrate is concentrated to dryness, concentrate
It extracts, distribute in methylene chloride and 0.5-1.5N aqueous hydrochloric acid solution, separate organic phase, organic phase successively uses saturated sodium bicarbonate
Aqueous solution and saturated common salt water washing, then with sodium sulphate drying and be spin-dried for, most V compound of formula is obtained through column chromatography for separation afterwards；
The preparation of S2, type I compound:
0.5-1.5g is weighed, V compound of formula of 1.0equiv. is in reactor, after the carbon tetrachloride dissolution dispersion of 5-15mL,
Successively into reaction system, in terms of V compound of formula, the bromating agent and 0.1-0.15equiv. that 1.2-1.4equiv. is added cause
Agent, after temperature rising reflux 4.5-5.5h, reaction solution is concentrated to dryness, the residue being concentrated to get, and the change of formula I is obtained after column chromatography for separation
Close object.
3. the palladium carbon catalysis bromo- 2- of reduction synthesis 2- (the fluoro- 3- methoxyphenyl of 2-) ethyl acetate according to claim 2
Method, which is characterized in that the mass fraction of hypophosphorous acid solution is 50% in the step S1.
4. the palladium carbon catalysis bromo- 2- of reduction synthesis 2- (the fluoro- 3- methoxyphenyl of 2-) ethyl acetate according to claim 2
Method, which is characterized in that the palladium carbon that palladium carbon is 5% in the step S1.
5. the palladium carbon catalysis bromo- 2- of reduction synthesis 2- (the fluoro- 3- methoxyphenyl of 2-) ethyl acetate according to claim 2
Method, which is characterized in that by 1.0g in the step S1, the Formula II compound of 1.0equiv. is added into reactor, with Formula II
Successively the palladium carbon of the sodium bicarbonate of 3.0equiv., the hypophosphorous acid solution of 4.0equiv., 0.1equiv. are added for compound meter
Into reactor, the cyclopentyl-methyl ether of 4mL and the water of 10mL is added, stirs and evenly mixs, is warming up to reflux, after back flow reaction 20h,
Reaction system is cooled to room temperature, reaction solution filtering, and filtrate is concentrated to dryness, and concentrate extracts in methylene chloride and 1N aqueous hydrochloric acid solution
It takes, distribute.
The preparation of S2, type I compound:
6. the palladium carbon catalysis bromo- 2- of reduction synthesis 2- (the fluoro- 3- methoxyphenyl of 2-) ethyl acetate according to claim 2
Method, which is characterized in that 1.0g is weighed in the step S2, V compound of formula of 1.0equiv. is in reactor, and the four of 10mL
Chlorination carbon dissolution dispersion after, successively into reaction system, in terms of V compound of formula, be added 1.2equiv. bromating agent and
0.1equiv. initiator, after temperature rising reflux 4.5h, reaction solution is concentrated to dryness, the residue being concentrated to get, after column chromatography for separation
Obtain type I compound.
7. the palladium carbon catalysis bromo- 2- of reduction synthesis 2- (the fluoro- 3- methoxyphenyl of 2-) ethyl acetate according to claim 6
Method, which is characterized in that the bromating agent is one of NBS, C5H6Br2N2O2.
8. the palladium carbon catalysis bromo- 2- of reduction synthesis 2- (the fluoro- 3- methoxyphenyl of 2-) ethyl acetate according to claim 7
Method, which is characterized in that the bromating agent is NBS.
9. the palladium carbon catalysis bromo- 2- of reduction synthesis 2- (the fluoro- 3- methoxyphenyl of 2-) ethyl acetate according to claim 6
Method, which is characterized in that the initiator is one of benzoyl peroxide, AIBN.
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Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2009062087A1 (en) * | 2007-11-07 | 2009-05-14 | Neurocrine Biosciences, Inc. | Processes for the preparation of uracil derivatives |
| US20160031857A1 (en) * | 2013-04-16 | 2016-02-04 | Grünenthal GmbH | Novel substituted condensed pyrimidine compounds |
| CN107602541A (en) * | 2016-07-11 | 2018-01-19 | 杭州国谋生物科技有限公司 | Hepatitis C virus NS5A inhibitor and application |
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- 2019-02-16 CN CN201910118477.2A patent/CN109761809A/en not_active Withdrawn
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2009062087A1 (en) * | 2007-11-07 | 2009-05-14 | Neurocrine Biosciences, Inc. | Processes for the preparation of uracil derivatives |
| US20160031857A1 (en) * | 2013-04-16 | 2016-02-04 | Grünenthal GmbH | Novel substituted condensed pyrimidine compounds |
| CN107602541A (en) * | 2016-07-11 | 2018-01-19 | 杭州国谋生物科技有限公司 | Hepatitis C virus NS5A inhibitor and application |
Non-Patent Citations (1)
| Title |
|---|
| 刘鹰翔主编: "《药物合成反应》", 31 August 2017, 中国医药出版社 * |
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Application publication date: 20190517 |