Disclosure of Invention
Based on the technical problems in the background art, the invention provides a preparation method of a silodosin intermediate, which has the advantages of novel route, cheap and easily-obtained reaction raw materials, environmental protection, convenient and simple operation, high yield and high purity of the prepared silodosin intermediate.
The invention provides a preparation method of a silodosin intermediate, which comprises the following synthetic route:
the method comprises the following steps:
performing transesterification on S1, salicylaldehyde (formula II) and ethylene carbonate to obtain 2- (2-hydroxyethoxy) benzaldehyde (formula III);
s2, carrying out Dakin oxidation reaction on 2- (2-hydroxyethoxy) benzaldehyde (formula III) to obtain 2- (2-hydroxyethoxy) sodium phenolate (formula IV);
s3, carrying out etherification reaction on 2- (2-hydroxyethoxy) sodium phenolate (formula IV) and trifluoroethanol to obtain 2- [2- (2,2, 2-trifluoroethoxy) phenoxy ] ethyl alcohol (formula V);
s4, 2- [2- (2,2, 2-trifluoroethoxy) phenoxy ] ethyl alcohol (formula V) and methanesulfonyl chloride are subjected to esterification reaction to obtain silodosin intermediate 2- [2- (2,2, 2-trifluoroethoxy) phenoxy ] ethyl methanesulfonate (formula I).
Preferably, in S1, the molar ratio of salicylaldehyde to ethylene carbonate is 1: 1-1.5, preferably 1: 1.1; preferably, the reaction temperature of the transesterification reaction is 110-130 ℃, the reaction time is 7-10h, preferably the reaction temperature is 120 ℃, and the reaction time is 8 h.
Preferably, in S1, the solvent for the transesterification reaction is one or more of N, N-dimethylformamide, N-dimethylacetamide, dimethylsulfoxide, and N-methylpyrrolidone, preferably N, N-dimethylformamide; preferably, the catalyst for the transesterification reaction is one or more of sodium carbonate, potassium carbonate, cesium carbonate, preferably potassium carbonate.
Preferably, in S2, the Dakin oxidation reaction is carried out at a temperature of 30-70 ℃ for 1-4 h.
Preferably, in S2, the peroxide used in the Dakin oxidation reaction is one or more of hydrogen peroxide, peracetic acid, tert-butyl hydroperoxide, oxone, m-chloroperoxybenzoic acid and peroxybenzoic acid, preferably hydrogen peroxide; preferably, the alkaline reagent used in the Dakin oxidation reaction is one or more of sodium hydroxide, potassium hydroxide, trimethyl benzyl ammonium hydroxide and tetramethyl amino hydroxide, and sodium hydroxide is preferred.
Preferably, in S3, the molar ratio of sodium 2- (2-hydroxyethoxy) phenolate to trifluoroethanol is 1: 1.5-2.5; preferably 1: 2.
preferably, in S3, the reaction temperature of the etherification reaction is 60-160 ℃, and the reaction time is 8-16 h; the reaction temperature is preferably 110 ℃ and the reaction time is 12 h.
Preferably, in S3, the solvent for the etherification reaction is one or more of N, N-dimethylformamide, N-dimethylacetamide, dimethylsulfoxide, and N-methylpyrrolidone, preferably N, N-dimethylformamide.
Preferably, in S4, the molar ratio of 2- [2- (2,2, 2-trifluoroethoxy) phenoxy ] ethyl alcohol to methanesulfonyl chloride is 1: 1.2-4.
The invention also provides a silodosin intermediate prepared by the method.
Has the advantages that: the invention discloses a preparation method of a silodosin intermediate, which has a novel route and a short synthetic route, and can prepare a target product only by four-step reaction. The method has the advantages of cheap and easily-obtained raw materials and reagents, environmental protection, mild and controllable reaction conditions, convenient and simple operation, good purity of the prepared silodosin intermediate, high yield, suitability for industrial production, wide prospect and industrial application value, and the purity of the product obtained in each step can reach more than 96%.
Detailed Description
Examples
The invention provides a preparation method of a silodosin intermediate, which comprises the following synthetic route:
the method comprises the following steps:
performing transesterification on S1, salicylaldehyde (formula II) and ethylene carbonate to obtain 2- (2-hydroxyethoxy) benzaldehyde (formula III);
s2, carrying out Dakin oxidation reaction on 2- (2-hydroxyethoxy) benzaldehyde (formula III) to obtain 2- (2-hydroxyethoxy) sodium phenolate (formula IV);
s3, carrying out etherification reaction on 2- (2-hydroxyethoxy) sodium phenolate (formula IV) and trifluoroethanol to obtain 2- [2- (2,2, 2-trifluoroethoxy) phenoxy ] ethyl alcohol (formula V);
s4, 2- [2- (2,2, 2-trifluoroethoxy) phenoxy ] ethyl alcohol (formula V) and methanesulfonyl chloride are subjected to esterification reaction to obtain silodosin intermediate 2- [2- (2,2, 2-trifluoroethoxy) phenoxy ] ethyl methanesulfonate (formula I).
It should be noted that, in the above steps S1-S4, other auxiliary steps for collecting the product, increasing the yield, increasing the purity of the product, removing impurities, etc. may be added, such as common auxiliary means of filtration, washing, extraction, purification, drying, etc.
The technical solution of the present invention will be described in detail below with reference to specific examples.
Example 1
The invention provides a preparation method of a silodosin intermediate, which comprises the following steps:
s1 Synthesis of 2- (2-hydroxyethoxy) benzaldehyde (formula III)
200g (1.64mol, 1.0eq) of salicylaldehyde participating in the reaction, 145g (1.64mol, 1.0eq) of ethylene carbonate, 535g (1.64mol, 1.0eq) of cesium carbonate, 600mL of dimethyl sulfoxide and 600mL of N-methylpyrrolidone are sequentially added into a 2000mL four-neck flask with mechanical stirring, the temperature is raised to 130 ℃ under the protection of nitrogen, the temperature is kept for reaction for 10 hours, the HPLC raw material is sampled and completely converted, the reaction system is cooled to room temperature, and the filtration is carried out. The filtrate was poured into 1000mL of ice water, extracted with 500mL x 3 of ethyl acetate, the organic phases were combined and dried over anhydrous sodium sulfate to give 200g of pale yellow oil with 73.3% yield and 97.8% purity.
S2 Synthesis of sodium 2- (2-hydroxyethoxy) phenolate (formula IV)
Under the protection of nitrogen, 166g (1.0mol, 1.0eq) of 2- (2-hydroxyethoxy) benzaldehyde and 1000mL (1.0mol, 1.0eq) of 1.0M potassium hydroxide which are involved in the reaction are sequentially added into a 2000mL four-neck flask with mechanical stirring, 300g (1.0mol, 1.0eq) of 30% tert-butyl hydroperoxide is slowly dropped into the flask under mechanical stirring, the reaction temperature is controlled to be not higher than 20 ℃, the temperature is raised to 30 ℃ after dropping is finished, the reaction is continued for 1 hour, the reaction is monitored by HPLC, after the raw materials are completely converted, the raw materials are quenched by sodium thiosulfate, the pH value is adjusted to about 5 by dilute hydrochloric acid, the raw materials are extracted by ethyl acetate, the oily materials are obtained by concentration, the oily materials are poured into a 1.0M sodium hydroxide aqueous solution, the pH value is adjusted to about 10, the mixture is stirred for 30 minutes, and the mixture is concentrated under reduced pressure to obtain 146g of off-white solid, the yield is 82.
S3 Synthesis of 2- [2- (2,2, 2-trifluoroethoxy) phenoxy ] ethyl alcohol (formula V)
Under the protection of nitrogen, 132g (0.75mol, 1.0eq) of sodium 2- (2-hydroxyethoxy) phenolate and 104g (0.75mol, 1.0eq) of potassium carbonate, 113g (1.13mol, 1.5eq) of trifluoroethanol, which are involved in the reaction, are sequentially added into a 2000mL four-necked flask with mechanical stirring, the temperature is raised to 60 ℃ for heat preservation and reaction for 8 hours, the reaction progress is monitored by HPLC, after the raw materials are completely converted, the mixture is cooled to room temperature, the reaction liquid is filtered, the filtrate is poured into 1000mL of ice water, the mixture is extracted by 500mL of 3 ethyl acetate, anhydrous sodium sulfate is dried, the dry light black oily substance is concentrated, and the colorless viscous liquid 143g is obtained by reduced pressure distillation, the yield is 80.8%, and the purity is 98.0%.
Synthesis of S4, 2- [2- (2,2, 2-trifluoroethoxy) phenoxy ] ethyl methanesulfonate (formula I)
In a 3000mL four-necked flask equipped with a mechanical stirrer, 129g (0.55mol, 1.0eq) of 2- [2- (2,2, 2-trifluoroethoxy) phenoxy ] ethyl alcohol, 67g (0.66mol, 1.2eq) of triethylamine, and 1000mL of dichloromethane were sequentially added to reduce the temperature of the reaction system to about 0 ℃ under an ice salt bath, and 75g (0.66mol, 1.2eq) of methanesulfonyl chloride dissolved in 500mL of dichloromethane was slowly added dropwise while controlling the temperature of the reaction system to be not higher than 20 ℃. After the dropwise addition, removing the deicing salt bath, heating to reflux reaction for 3 hours, cooling to room temperature, filtering to remove triethylamine hydrochloride, washing the filtrate with 1000ml of 3 saturated sodium carbonate, drying with anhydrous sodium sulfate, filtering, concentrating the dried gray oily substance under reduced pressure, adding 400g of isopropanol, stirring at 0 ℃ for crystallization for 6 hours, filtering, and drying in vacuum to obtain 150g of white solid, wherein the melting point is 39-42 ℃, the yield is 86.7%, and the purity is 98.0%.
Example 2
The invention provides a preparation method of a silodosin intermediate, which comprises the following steps:
s1 Synthesis of 2- (2-hydroxyethoxy) benzaldehyde (formula III)
200g (1.64mol, 1.0eq) of salicylaldehyde participating in the reaction, 217g (2.46mol, 1.5eq) of ethylene carbonate, 679g (4.92mol, 3.0eq) of potassium carbonate and 1000mL of N, N-dimethylacetamide are sequentially added into a 2000mL four-neck flask with mechanical stirring, the temperature is raised to 110 ℃ under the protection of nitrogen, the reaction is kept for 7 hours, the HPLC raw material is sampled and completely converted, the reaction system is cooled to room temperature, and the mixture is filtered. The filtrate was poured into 1000mL of ice water, extracted with 500mL x 3 of ethyl acetate, the organic phases were combined and dried over anhydrous sodium sulfate to give 216g of pale yellow oil with 79.1% yield and 98.0% purity.
S2 Synthesis of sodium 2- (2-hydroxyethoxy) phenolate (formula IV)
Under the protection of nitrogen, 200g (1.2mol, 1.0eq) of 2- (2-hydroxyethoxy) benzaldehyde to be reacted, 100g (0.6mol, 0.5eq) of trimethyl benzyl ammonium hydroxide and 1200mL (1.2mol, 1.0eq) of 1.0M sodium hydroxide are sequentially added into a 2000mL four-neck flask with mechanical stirring, 547g (2.16mol, 1.8eq) of 30% peracetic acid is slowly dropped into the flask under mechanical stirring, the temperature of the reaction is controlled to be not higher than 20 ℃, the flask is heated to 70 ℃ after dropping, the reaction is continued for 4 hours, the HPLC monitors the reaction, the raw materials are quenched by sodium thiosulfate after complete conversion, the pH is adjusted to about 5 by dilute hydrochloric acid, the raw materials are extracted by ethyl acetate, oil is obtained by concentration, the oily matter is poured into 1.0M sodium hydroxide aqueous solution, the pH is adjusted to about 10, after stirring for 30 minutes, the oily matter is concentrated by decompression, the off-white solid is obtained by concentration, the yield is 88.7%, and the purity is 96.7%.
S3 Synthesis of 2- [2- (2,2, 2-trifluoroethoxy) phenoxy ] ethyl alcohol (formula V)
Under the protection of nitrogen, 176g (1.0mol, 1.0eq) of sodium 2- (2-hydroxyethoxy) phenolate participating in the reaction, 414g (3.0mol, 3.0eq) of potassium carbonate, 250g (2.5mol, 2.5eq) of trifluoroethanol, 400mL of N-methylpyrrolidone and 1000mL of N, N-dimethylformamide are added in sequence into a 2000mL four-neck flask with mechanical stirring, the temperature is raised to 160 ℃, the reaction is kept for 16 hours, the reaction process is monitored by HPLC, after the raw materials are completely converted, the reaction liquid is cooled to room temperature, the reaction liquid is filtered, the filtrate is poured into 1000mL of ice water, and then the ice water is extracted by 500mL of ethyl acetate of 3, dried by anhydrous sodium sulfate, a dry black light oily substance is concentrated, and the colorless viscous liquid is obtained by reduced pressure distillation, the yield is 89.8%, and the purity is 98.4%.
Synthesis of S4, 2- [2- (2,2, 2-trifluoroethoxy) phenoxy ] ethyl methanesulfonate (formula I)
200g (0.85mol, 1.0eq) of 2- [2- (2,2, 2-trifluoroethoxy) phenoxy ] ethyl alcohol, 155g (1.53mol, 1.8eq) of triethylamine and 2400mL of dichloromethane which are involved in the reaction were sequentially added to a 5000mL four-necked flask equipped with a mechanical stirrer, and the temperature of the reaction system was lowered to about 0 ℃ under an ice salt bath, and 388g (3.4mol, 4.0eq) of methanesulfonyl chloride dissolved in 1000mL of dichloromethane was slowly added dropwise while controlling the temperature of the reaction system to be not higher than 20 ℃. After the dropwise addition, removing the deicing salt bath, heating to reflux reaction for 4 hours, cooling to room temperature, filtering to remove triethylamine hydrochloride, washing the filtrate with 1000ml of 3 saturated sodium carbonate, drying with anhydrous sodium sulfate, filtering, concentrating the dried gray oily substance under reduced pressure, adding 400g of isopropanol, stirring at 0 ℃ for crystallization for 6 hours, filtering, and drying in vacuum to obtain 247g of white solid, wherein the melting point is 39-42 ℃, the yield is 92.5%, and the purity is 98.3%.
Example 3
The invention provides a preparation method of a silodosin intermediate, which comprises the following steps:
s1 Synthesis of 2- (2-hydroxyethoxy) benzaldehyde (formula III)
200g (1.64mol, 1.0eq) of salicylaldehyde participating in the reaction, 188g (2.13mol, 1.3eq) of ethylene carbonate, 680g (2.46mol, 3.0eq) of potassium carbonate and 1000mL of N, N-dimethylformamide are sequentially added into a 2000mL four-neck flask with mechanical stirring, the temperature is raised to 120 ℃ under the protection of nitrogen, the reaction is kept for 9 hours, the HPLC raw material is sampled and completely converted, the reaction system is cooled to the room temperature, and the mixture is filtered. The filtrate was poured into 1000mL of ice water, extracted with 500mL x 3 of ethyl acetate, the organic phases were combined and dried over anhydrous sodium sulfate to give 214g of pale yellow oil with a yield of 78.4% and a purity of 98.2%.
S2 Synthesis of sodium 2- (2-hydroxyethoxy) phenolate (formula IV)
Under the protection of nitrogen, 200g (1.2mol, 1.0eq) of 2- (2-hydroxyethoxy) benzaldehyde and 1440mL (1.44mol,1.2eq) of 1.0M sodium hydroxide which are involved in the reaction are sequentially added into a 2000mL four-neck flask with mechanical stirring, 205g (1.8mol,1.5eq) of 30% hydrogen peroxide is slowly dropped into the flask with mechanical stirring, the reaction temperature is controlled to be not higher than 20 ℃, the temperature is raised to 50 ℃ after the dropping is finished, the reaction is continued for 3 hours, the reaction is monitored by HPLC, after the raw materials are completely converted, the raw materials are quenched by sodium thiosulfate, the pH value is adjusted to about 5 by dilute hydrochloric acid, the raw materials are extracted by ethyl acetate, the raw materials are concentrated to obtain oily substances, the oily substances are poured into a 1.0M sodium hydroxide aqueous solution, the pH value is adjusted to about 10, the mixture is stirred for 30 minutes, and the mixture is concentrated to obtain 192g of off-white solid, the yield is.
S3 Synthesis of 2- [2- (2,2, 2-trifluoroethoxy) phenoxy ] ethyl alcohol (formula V)
Under the protection of nitrogen, 176g (1.0mol, 1.0eq) of sodium 2- (2-hydroxyethoxy) phenolate, 276g (2.0mol, 2.0eq) of potassium carbonate, 220g (2.2mol, 2.2eq) of trifluoroethanol and 1200mL of N, N-dimethylformamide which are involved in the reaction are sequentially added into a 2000mL four-neck flask with mechanical stirring, the temperature is raised to 80 ℃ for heat preservation and reaction is carried out for 10 hours, the reaction progress is monitored by HPLC, after the raw materials are completely converted, the reaction liquid is cooled to room temperature, the reaction liquid is filtered, the filtrate is poured into 1000mL of ice water, the ice water is extracted by 500mL of ethyl acetate of 3, anhydrous sodium sulfate is dried, dry light black oily matter is concentrated, and the colorless viscous liquid 207g, the yield is 87.7 percent and the purity is 98.0 percent are obtained by reduced pressure distillation.
Synthesis of S4, 2- [2- (2,2, 2-trifluoroethoxy) phenoxy ] ethyl methanesulfonate (formula I)
In a 3000mL four-necked flask equipped with a mechanical stirrer, 200g (0.85mol, 1.0eq) of 2- [2- (2,2, 2-trifluoroethoxy) phenoxy ] ethyl alcohol, 112g (1.1mol, 1.5eq) of triethylamine, and 2000mL of dichloromethane were sequentially added to react, and the temperature of the reaction system was lowered to about 0 ℃ in an ice salt bath, and 194g (1.7mol, 2.0eq) of methanesulfonyl chloride dissolved in 500mL of dichloromethane was slowly added dropwise while controlling the temperature of the reaction system to be not higher than 20 ℃. After the dropwise addition, removing the deicing salt bath, heating to reflux reaction for 5 hours, cooling to room temperature, filtering to remove triethylamine hydrochloride, washing the filtrate by 1000ml of 3 saturated sodium carbonate, drying by anhydrous sodium sulfate, filtering, concentrating the dried gray oily substance under reduced pressure, adding 400g of isopropanol, stirring at 0 ℃ for crystallization for 6 hours, filtering, and drying in vacuum to obtain 245g of white solid, wherein the melting point is 39-42 ℃, the yield is 91.7%, and the purity is 98.2%.
Example 4
The invention provides a preparation method of a silodosin intermediate, which comprises the following steps:
s1 Synthesis of 2- (2-hydroxyethoxy) benzaldehyde (formula III)
200g (1.64mol, 1.0eq) of salicylaldehyde participating in the reaction, 159g (1.8mol, 1.1eq) of ethylene carbonate, 340g (2.46mol, 1.5eq) of potassium carbonate and 1000mL of N, N-dimethylformamide are sequentially added into a 2000mL four-neck flask with mechanical stirring, the temperature is raised to 120 ℃ under the protection of nitrogen, the reaction is kept for 8 hours, the HPLC raw material is sampled and completely converted, the reaction system is cooled to the room temperature, and the mixture is filtered. The filtrate was poured into 1000mL of ice water, extracted with 500mL x 3 of ethyl acetate, the organic phases were combined and dried over anhydrous sodium sulfate to give 216g of pale yellow oil with 79.1% yield and 98.2% purity.
S2 Synthesis of sodium 2- (2-hydroxyethoxy) phenolate (formula IV)
Under the protection of nitrogen, 200g (1.2mol, 1.0eq) of 2- (2-hydroxyethoxy) benzaldehyde and 1440mL (1.44mol,1.2eq) of 1.0M sodium hydroxide which are involved in the reaction are sequentially added into a 2000mL four-neck flask with mechanical stirring, 164g (1.44mol,1.2eq) of 30% hydrogen peroxide is slowly dropped under mechanical stirring, the reaction temperature is controlled to be not higher than 20 ℃, after the dropping is finished, the temperature is raised to 30 ℃ for continuous reaction for 2 hours, the reaction is monitored by HPLC, after the raw materials are completely converted, the raw materials are quenched by sodium thiosulfate, the pH value is adjusted to about 5 by dilute hydrochloric acid, the raw materials are extracted by ethyl acetate, the raw materials are concentrated to obtain oily substances, the oily substances are poured into a 1.0M sodium hydroxide aqueous solution, the pH value is adjusted to about 10, after the stirring is carried out for 30 minutes, the raw materials are concentrated to obtain 192g of off-white solid, the yield is 90..
S3 Synthesis of 2- [2- (2,2, 2-trifluoroethoxy) phenoxy ] ethyl alcohol (formula V)
Under the protection of nitrogen, 176g (1.0mol, 1.0eq) of sodium 2- (2-hydroxyethoxy) phenolate participating in the reaction, 207g (1.5mol, 1.5eq) of potassium carbonate, 200g (2.0mol, 2.0eq) of trifluoroethanol and 1200mL of N, N-dimethylformamide were added in sequence to a 2000mL four-neck flask equipped with mechanical stirring, the temperature was raised to 110 ℃ and the reaction was kept for 12 hours, the reaction progress was monitored by HPLC, after the conversion of the raw materials was completed, the reaction solution was cooled to room temperature, the reaction solution was filtered, the filtrate was poured into 1000mL of ice water, and then extracted with 500mL of ethyl acetate of 3, dried over anhydrous sodium sulfate, concentrated to a dry light black oily substance, and distilled under reduced pressure to obtain 210g of colorless viscous liquid with yield of 89.0% and purity of 98.4%.
Synthesis of S4, 2- [2- (2,2, 2-trifluoroethoxy) phenoxy ] ethyl methanesulfonate (formula I)
In a 3000mL four-necked flask equipped with a mechanical stirrer, 200g (0.85mol, 1.0eq) of 2- [2- (2,2, 2-trifluoroethoxy) phenoxy ] ethyl alcohol, 129g (1.27mol, 1.5eq) of triethylamine, and 2000mL of dichloromethane were sequentially added to the reaction system, and the temperature of the reaction system was lowered to about 0 ℃ in an ice salt bath, and 145g (1.27mol, 1.5eq) of methanesulfonyl chloride dissolved in 500mL of dichloromethane was slowly added dropwise while controlling the temperature of the reaction system to be not higher than 20 ℃. After the dropwise addition, removing an ice salt bath, heating to reflux reaction for 4 hours, cooling to room temperature, filtering to remove triethylamine hydrochloride, washing the filtrate by 1000ml of 3 saturated sodium carbonate, drying by anhydrous sodium sulfate, filtering, concentrating the dried gray oily substance under reduced pressure, adding 400g of isopropanol, stirring at 0 ℃ for crystallization for 6 hours, filtering, and drying in vacuum to obtain 246g of white solid, wherein the melting point is 39-42 ℃, the yield is 92.1%, and the purity is 98.4%.
The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be considered to be within the technical scope of the present invention, and the technical solutions and the inventive concepts thereof according to the present invention should be equivalent or changed within the scope of the present invention.