CS268279B1 - Method of 5-hydroxy-2-pentanone preparation - Google Patents
Method of 5-hydroxy-2-pentanone preparation Download PDFInfo
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- CS268279B1 CS268279B1 CS875422A CS542287A CS268279B1 CS 268279 B1 CS268279 B1 CS 268279B1 CS 875422 A CS875422 A CS 875422A CS 542287 A CS542287 A CS 542287A CS 268279 B1 CS268279 B1 CS 268279B1
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- pentanone
- hydroxy
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- ether
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- JSHPTIGHEWEXRW-UHFFFAOYSA-N 5-hydroxypentan-2-one Chemical compound CC(=O)CCCO JSHPTIGHEWEXRW-UHFFFAOYSA-N 0.000 title claims abstract description 12
- 238000000034 method Methods 0.000 title claims abstract description 8
- 238000002360 preparation method Methods 0.000 title claims abstract description 5
- CDBYLPFSWZWCQE-UHFFFAOYSA-L Sodium Carbonate Chemical compound [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 claims abstract description 9
- 229910000029 sodium carbonate Inorganic materials 0.000 claims abstract description 5
- XLYOFNOQVPJJNP-UHFFFAOYSA-M hydroxide Chemical compound [OH-] XLYOFNOQVPJJNP-UHFFFAOYSA-M 0.000 claims abstract description 4
- NBTOZLQBSIZIKS-UHFFFAOYSA-N methoxide Chemical compound [O-]C NBTOZLQBSIZIKS-UHFFFAOYSA-N 0.000 claims abstract description 4
- 230000001476 alcoholic effect Effects 0.000 claims abstract description 3
- 125000000217 alkyl group Chemical group 0.000 claims abstract description 3
- HHFAWKCIHAUFRX-UHFFFAOYSA-N ethoxide Chemical compound CC[O-] HHFAWKCIHAUFRX-UHFFFAOYSA-N 0.000 claims abstract description 3
- BWHMMNNQKKPAPP-UHFFFAOYSA-L potassium carbonate Chemical compound [K+].[K+].[O-]C([O-])=O BWHMMNNQKKPAPP-UHFFFAOYSA-L 0.000 claims description 6
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 claims description 4
- 229910000027 potassium carbonate Inorganic materials 0.000 claims description 3
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims 1
- 229910052799 carbon Inorganic materials 0.000 claims 1
- ZLMJMSJWJFRBEC-UHFFFAOYSA-N Potassium Chemical compound [K] ZLMJMSJWJFRBEC-UHFFFAOYSA-N 0.000 abstract 1
- 238000006266 etherification reaction Methods 0.000 abstract 1
- 229910052700 potassium Inorganic materials 0.000 abstract 1
- 239000011591 potassium Substances 0.000 abstract 1
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 27
- RTZKZFJDLAIYFH-UHFFFAOYSA-N Diethyl ether Chemical compound CCOCC RTZKZFJDLAIYFH-UHFFFAOYSA-N 0.000 description 22
- 239000011541 reaction mixture Substances 0.000 description 11
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 10
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 10
- 238000006243 chemical reaction Methods 0.000 description 7
- WOVLKKLXYZJMSN-UHFFFAOYSA-N 1-Hydroxy-2-pentanone Chemical compound CCCC(=O)CO WOVLKKLXYZJMSN-UHFFFAOYSA-N 0.000 description 5
- 239000001569 carbon dioxide Substances 0.000 description 5
- 229910002092 carbon dioxide Inorganic materials 0.000 description 5
- HTSAVXAFEVUJQE-UHFFFAOYSA-N 1-isothiocyanato-2-methoxyethane Chemical compound COCCN=C=S HTSAVXAFEVUJQE-UHFFFAOYSA-N 0.000 description 4
- WQDUMFSSJAZKTM-UHFFFAOYSA-N Sodium methoxide Chemical compound [Na+].[O-]C WQDUMFSSJAZKTM-UHFFFAOYSA-N 0.000 description 4
- 238000001704 evaporation Methods 0.000 description 4
- 230000008020 evaporation Effects 0.000 description 4
- KWYUFKZDYYNOTN-UHFFFAOYSA-M Potassium hydroxide Chemical compound [OH-].[K+] KWYUFKZDYYNOTN-UHFFFAOYSA-M 0.000 description 3
- UUGPQIGKAFRSKA-UHFFFAOYSA-N 4-oxopentyl formate Chemical compound CC(=O)CCCOC=O UUGPQIGKAFRSKA-UHFFFAOYSA-N 0.000 description 2
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 2
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 2
- 230000007062 hydrolysis Effects 0.000 description 2
- 238000006460 hydrolysis reaction Methods 0.000 description 2
- 229910052708 sodium Inorganic materials 0.000 description 2
- 239000011734 sodium Substances 0.000 description 2
- HEMHJVSKTPXQMS-UHFFFAOYSA-M sodium hydroxide Inorganic materials [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 2
- 238000003756 stirring Methods 0.000 description 2
- 238000003786 synthesis reaction Methods 0.000 description 2
- FIEOBSHFFQVFAH-UHFFFAOYSA-N 5-(2-methyloxolan-2-yl)oxypentan-2-one Chemical compound CC(=O)CCCOC1(C)CCCO1 FIEOBSHFFQVFAH-UHFFFAOYSA-N 0.000 description 1
- BVKZGUZCCUSVTD-UHFFFAOYSA-L Carbonate Chemical compound [O-]C([O-])=O BVKZGUZCCUSVTD-UHFFFAOYSA-L 0.000 description 1
- BDAGIHXWWSANSR-UHFFFAOYSA-M Formate Chemical compound [O-]C=O BDAGIHXWWSANSR-UHFFFAOYSA-M 0.000 description 1
- 230000002378 acidificating effect Effects 0.000 description 1
- 238000006136 alcoholysis reaction Methods 0.000 description 1
- 229910052783 alkali metal Inorganic materials 0.000 description 1
- 229910000288 alkali metal carbonate Inorganic materials 0.000 description 1
- 150000008041 alkali metal carbonates Chemical class 0.000 description 1
- -1 alkali metal methoxide Chemical class 0.000 description 1
- 239000002585 base Substances 0.000 description 1
- 239000011324 bead Substances 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 238000004821 distillation Methods 0.000 description 1
- 239000003814 drug Substances 0.000 description 1
- 229940079593 drug Drugs 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000012456 homogeneous solution Substances 0.000 description 1
- 239000003999 initiator Substances 0.000 description 1
- 150000002500 ions Chemical class 0.000 description 1
- 238000002955 isolation Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 238000000655 nuclear magnetic resonance spectrum Methods 0.000 description 1
- 229920000642 polymer Polymers 0.000 description 1
- BDAWXSQJJCIFIK-UHFFFAOYSA-N potassium methoxide Chemical compound [K+].[O-]C BDAWXSQJJCIFIK-UHFFFAOYSA-N 0.000 description 1
- QDRKDTQENPPHOJ-UHFFFAOYSA-N sodium ethoxide Chemical compound [Na+].CC[O-] QDRKDTQENPPHOJ-UHFFFAOYSA-N 0.000 description 1
- 239000007858 starting material Substances 0.000 description 1
- JZRWCGZRTZMZEH-UHFFFAOYSA-N thiamine Chemical compound CC1=C(CCO)SC=[N+]1CC1=CN=C(C)N=C1N JZRWCGZRTZMZEH-UHFFFAOYSA-N 0.000 description 1
- 238000004809 thin layer chromatography Methods 0.000 description 1
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- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
Sečení se týká způsobu přípravy 5-hydroxy-2-pentanonu obecného vzorce I alkalickou reeeterifikaoí 4-oxopentylalkanoátů obeoného vzorce II, kde R-H nebo alkyl o počtu uhlíků C. až C,, působením alkoholického roztoku methoxidu nebo ethoxidu nebo hydroxidu nebo uhličitanu sodného nebo draselného.Mowing refers to the method of preparation 5-hydroxy-2-pentanone of the formula Alkaline re-etherification of 4-oxopentylalkanoates of Formula II where R-H or alkyl having the number of carbons C to C, by treatment with an alcoholic solution methoxide or ethoxide or hydroxide or sodium carbonate or potassium.
Description
Vynález se týká způsobu přípravy 5-hydroxy-2-pentanonu vzoroe I.The invention relates to a process for the preparation of 5-hydroxy-2-pentanone of formula I.
5-Hydroxy-2-pentanon vzorce I je důležitým meziproduktem v organické syntéze. Je výchozí látkou pro výrobu léčiv, vitaminu B 1 a azoiniciátorů, používaných k syntéze teleohelickýoh polymerů.5-Hydroxy-2-pentanone of formula I is an important intermediate in organic synthesis. It is the starting material for the production of drugs, vitamin B 1 and azo initiators used for the synthesis of teleohelical polymers.
Hydrolýza nebo alkoholýza 4-oxopentylaoetátu na hydroxy-pentanon vzoroe I se provádí v roztoku alkoholů za katalýzy kyselinou chlorovodíkovou, kyselinou sírovou nebo kyselými měniči lontů (Grigoriev A. A., Kayman E. A., Bobrov Λ, P., Danko T. N., Pinkhaaik E. V.: Khim. Prom. (Moscow) 8, 45β /1981/). Reakční směsi po hydrolýze se musí neutralizovat básemi a hydroxypentanon obecného vzorce I izolovat destilací. Za těchto podmínek však dochází k částečné přeměně hydroxypentanonu vzorce I na 2-methyl2-/4-oxopentyloXy/-tetrahydrofuran vzorce III.The hydrolysis or alcoholysis of 4-oxopentyl acetate to the hydroxypentanone of formula I is carried out in alcohol solution catalyzed by hydrochloric acid, sulfuric acid or acidic ion exchangers (Grigoriev AA, Kayman EA, Bobrov®, P., Danko TN, Pinkhaaik EV: Khim. Prom. (Moscow) 8, 45β (1981). The reaction mixtures after hydrolysis must be neutralized with bases and the hydroxypentanone of the formula I isolated by distillation. Under these conditions, however, the hydroxypentanone of the formula I is partially converted to the 2-methyl-2- (4-oxopentyloxy) -tetrahydrofuran of the formula III.
Uvedené nedostatky odstraňuje způsob přípravy hydroxypentanonu vzorce I podle vynálezu. Jeho podstata spočívá v tom, že se na 4-oxopentylalkanoát obecného vzorce II, kde R-H nebo alkyl o počtu uhlíků až C^, působí alkoholickým roztokem methoxldu nebo ethoxidu nebo hydroxidu nebo uhličitanu sodného nebo draselného při teplotách 10 až 40 °C, výhodné potom při laboratorní teplotě. Reakce se uskuteční tak, že se 4-oxopentylalkanoát obecného vzorce II rozpustí v methanoliokém nebo ethanolickém roztokui methoxidu nebo hydroxidu nebo uhličitanu sodného nebo draselného a reakční srnče se ponechá stát za občasného promíchání při teplotě 10 až 40 °C, výhodné potom pří laboratorní teploté. Průbéh reakce lze sledovat chromátograíií reakční amčsi na tenké vrstvč. Po dosažení úplné konverze 4-oxopentylalkanoátu obecného vzorce II na hydroxy-pentanon vzoroe I se methoxid nebo hydroxid alkalického kovu neutralizuje oxidem uhličitým, methanol se odpaří za sníženého tlaku, vyloučený^uhličitan alkalického kovu se odfiltruje a prorayje etherem. Po odpaření etheru se získá 5-hydroxy-2-pentanon vzorce I, který je dostatečné čistý pro daléí použití.The process for the preparation of hydroxypentanone of the formula I according to the invention overcomes these drawbacks. Its essence lies in the fact that the 4-oxopentylalkanoate of the general formula II, in which RH or alkyl having a number of carbons up to C14, is treated with an alcoholic solution of methoxide or ethoxide or sodium or potassium hydroxide or carbonate at temperatures of 10 to 40 ° C, preferably then at room temperature. The reaction is carried out by dissolving the 4-oxopentylalkanoate of the formula II in a methanolic or ethanolic solution of methoxide or sodium or potassium methoxide or hydroxide and allowing the reaction mixture to stand with occasional stirring at 10-40 ° C, preferably at room temperature. The progress of the reaction can be monitored by thin layer chromatography of the reaction mixture. After complete conversion of the 4-oxopentylalkanoate of the formula II to the hydroxypentanone of the formula I, the alkali metal methoxide or hydroxide is neutralized with carbon dioxide, the methanol is evaporated off under reduced pressure, the precipitated alkali metal carbonate is filtered off and washed with ether. After evaporation of the ether, 5-hydroxy-2-pentanone of formula I is obtained, which is sufficiently pure for further use.
Účinek postupu podle vynálezu spočívá v tom, že alkalická reesterifikace 4-oxoe pentylalkanoátů obecného vzorce II probíhá kvantitativné za velmi mírných reakčníoh podmínek. Výhodou postupu jsou vysoké výtéžky prakticky čistého 5-hydroxy-2-pentanonu vzoroe I, mírné reakční podmínky a snadná izolace produktu.The effect of the process according to the invention is that the alkaline reesterification of the 4-oxo pentylalkanoates of the formula II takes place quantitatively under very mild reaction conditions. The advantages of the process are high yields of practically pure 5-hydroxy-2-pentanone of formula I, mild reaction conditions and easy isolation of the product.
Způsob podle vynálezu je dále popsán na nékolika příkladech provedení.The process according to the invention is further described by means of several exemplary embodiments.
Příklad 1Example 1
4-Oxopentylacetát (II, R-CH^', 21,6 gj 0,15 mol) byl rozpuštén v méthanolu (150 ml), obsahujícím methoxid sodný (0,2 g). Vzniklý homogenní roztok byl ponechán stát 5 hodin za laboratorní teploty. Potom byla reakční srnče zneutralizována uvádčním oxidu uhličitého, methanol byl z reakční smčsi odpařen za sníženého tlaku a zbytek byl extrahován etherem. Po odpaření etheru bylo získáno i 4,7 g (96 %) ohromatograficky čistého 5-hydroxy-2-pentanonu, jehož struktura byla prokázána NMR spektrem.4-Oxopentyl acetate (II, R-CH 2 Cl 2, 21.6 g, 0.15 mol) was dissolved in methanol (150 mL) containing sodium methoxide (0.2 g). The resulting homogeneous solution was allowed to stand for 5 hours at room temperature. Then, the reaction mixture was neutralized with the indicated carbon dioxide, the methanol was evaporated from the reaction mixture under reduced pressure, and the residue was extracted with ether. After evaporation of the ether, 4.7 g (96%) of chromatographically pure 5-hydroxy-2-pentanone were obtained, the structure of which was proved by NMR spectrum.
Příklad 2 . Roztok 4-oxopentylformiátu (II, R-Ηζ 13·θ θ·1 m°D v méthanolu (100 ml) obsahujícím methoxid sodný (0,2 g) byl ponechán stát při laboratorní teploté po dobu 2 hodin. Během této doby bylo dosaženo úplné konverze výchozího oxopentylformiátu obecného vzorci II (R-H). Reakční směs byla potom neutralizována zaváděním oxidu uhličitého, methanol byl odpařen za sníženého tlaku, vyloučený uhličitan sodný byl odfiltrován a zbytek byl extrahován etherem. Po oddestilování etheru bylo získáno 9,7 g (95 %) ohromatograficky čistého 5-hydroxy-2-pentanonu.Example 2. A solution of 4-oxopentyl formate (II, R-Ηζ 13 · θ θ · 1 m ° D in methanol (100 ml) containing sodium methoxide (0.2 g) was allowed to stand at room temperature for 2 hours. During this time, complete conversion of the starting oxopentyl formate of formula II (RH), the reaction mixture was neutralized by the introduction of carbon dioxide, the methanol was evaporated under reduced pressure, the precipitated sodium carbonate was filtered off and the residue was extracted with ether to give 9.7 g (95%). ) in chromatographically pure 5-hydroxy-2-pentanone.
Příklad 3Example 3
Reakční srnče obsahující 4-oxopentylformiát (II, R-Ηζ 10,0 g', 0,77 mol), methanol (100 ml) a uhličitan draselný (2,0 g) byla míchána 10 hodin při teplotě 30 až 40 °C. Potom byl methanol odpařen na- vakuu, uhličitan draselný byl odfiltrován a zbytek byl extrahován etherem. Po oddestilování etheru bylo získáno 7,1 g (90,5 %) 5-hydroxy-2-pentanonu.The reaction beads containing 4-oxopentyl formate (II, R-Ηζ 10.0 g ', 0.77 mol), methanol (100 ml) and potassium carbonate (2.0 g) were stirred at 30-40 ° C for 10 hours. Then the methanol was evaporated in vacuo, the potassium carbonate was filtered off and the residue was extracted with ether. After distilling off the ether, 7.1 g (90.5%) of 5-hydroxy-2-pentanone were obtained.
Příklad 4Example 4
Reakční směs, obsahující 4-oxopentylacetát (II, R-CH^)*, 14,4 g', 0,1 mol), ethanol (100 ml) a ethoxid sodný (0,2 g) byla ponechána stát při laboratorní teplotS za občasného promíchání po dobu 9 hodin. Potom byla reakční směs neutralizována plynným oxidem uhličitým, ethanol byl z reakční směsi odpařen za sníženého tlaku, vyloučený uhličitan sodný byl odfiltrován a zbytek byl extrahován etherem. Po odpaření etheru bylo získáno 9,1 g (89,2 %) 5-hydroxy-2-pentanonu.The reaction mixture containing 4-oxopentyl acetate (II, R-CH 2) *, 14.4 g (0.1 mol), ethanol (100 ml) and sodium ethoxide (0.2 g) was allowed to stand at room temperature under occasional stirring for 9 hours. Then, the reaction mixture was neutralized with carbon dioxide gas, the ethanol was evaporated from the reaction mixture under reduced pressure, the precipitated sodium carbonate was filtered off, and the residue was extracted with ether. After evaporation of the ether, 9.1 g (89.2%) of 5-hydroxy-2-pentanone were obtained.
Příklad 5Example 5
Ke směsi methanolu (50 ml) a ethanolu (50 ml) byl přidán sodík (0,1 g) a po jeho zreagování byl do roztoku přidán 4-oxopentylacetát (II, R-CHj ζ 12,1 g). Reakční směs byla ponechána stát při laboratorní teplotě po dobu 8 hodin. Potom byla reakční směs neutralizována oxidem uhličitým, methanol a ethanol byly odpařeny za sníženého tlaku, vyloučený uhličitan sodný byl odfiltrován a zbytek byl extrahován etherem. Po odpaření etheru bylo získáno 7,5 g 5-hydroxy-2-pentanonu.Sodium (0.1 g) was added to a mixture of methanol (50 ml) and ethanol (50 ml), and after reacting, 4-oxopentyl acetate (II, R-CH 2 ζ 12.1 g) was added to the solution. The reaction mixture was allowed to stand at room temperature for 8 hours. Then the reaction mixture was neutralized with carbon dioxide, methanol and ethanol were evaporated under reduced pressure, the precipitated sodium carbonate was filtered off and the residue was extracted with ether. After evaporation of the ether, 7.5 g of 5-hydroxy-2-pentanone were obtained.
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Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CS875422A CS268279B1 (en) | 1987-07-17 | 1987-07-17 | Method of 5-hydroxy-2-pentanone preparation |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CS875422A CS268279B1 (en) | 1987-07-17 | 1987-07-17 | Method of 5-hydroxy-2-pentanone preparation |
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| Publication Number | Publication Date |
|---|---|
| CS542287A1 CS542287A1 (en) | 1989-08-14 |
| CS268279B1 true CS268279B1 (en) | 1990-03-14 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CS875422A CS268279B1 (en) | 1987-07-17 | 1987-07-17 | Method of 5-hydroxy-2-pentanone preparation |
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| Country | Link |
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| CS (1) | CS268279B1 (en) |
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1987
- 1987-07-17 CS CS875422A patent/CS268279B1/en unknown
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| Publication number | Publication date |
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| CS542287A1 (en) | 1989-08-14 |
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