US2590163A - Production of an acid of the ascorbic acid type from a 2-keto-hexonic acid - Google Patents
Production of an acid of the ascorbic acid type from a 2-keto-hexonic acid Download PDFInfo
- Publication number
- US2590163A US2590163A US92520A US9252049A US2590163A US 2590163 A US2590163 A US 2590163A US 92520 A US92520 A US 92520A US 9252049 A US9252049 A US 9252049A US 2590163 A US2590163 A US 2590163A
- Authority
- US
- United States
- Prior art keywords
- acid
- ascorbic acid
- keto
- hexonic
- ascorbic
- 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 - Lifetime
Links
- CIWBSHSKHKDKBQ-JLAZNSOCSA-N Ascorbic acid Chemical compound OC[C@H](O)[C@H]1OC(=O)C(O)=C1O CIWBSHSKHKDKBQ-JLAZNSOCSA-N 0.000 title claims description 51
- 229960005070 ascorbic acid Drugs 0.000 title claims description 25
- 235000010323 ascorbic acid Nutrition 0.000 title claims description 24
- 239000002253 acid Substances 0.000 title claims description 22
- 239000011668 ascorbic acid Substances 0.000 title claims description 22
- 238000004519 manufacturing process Methods 0.000 title claims description 5
- 239000000706 filtrate Substances 0.000 claims description 10
- 229910001385 heavy metal Inorganic materials 0.000 claims description 7
- 239000000126 substance Substances 0.000 claims description 7
- 150000001875 compounds Chemical class 0.000 claims description 6
- 150000003839 salts Chemical class 0.000 claims description 6
- 238000010438 heat treatment Methods 0.000 claims description 5
- 150000004679 hydroxides Chemical class 0.000 claims description 5
- 238000000034 method Methods 0.000 claims description 5
- RWSOTUBLDIXVET-UHFFFAOYSA-N Dihydrogen sulfide Chemical compound S RWSOTUBLDIXVET-UHFFFAOYSA-N 0.000 claims description 4
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims description 4
- 239000012141 concentrate Substances 0.000 claims description 4
- 238000001914 filtration Methods 0.000 claims description 4
- 239000002244 precipitate Substances 0.000 claims description 4
- UCKMPCXJQFINFW-UHFFFAOYSA-N Sulphide Chemical compound [S-2] UCKMPCXJQFINFW-UHFFFAOYSA-N 0.000 claims 1
- 235000008504 concentrate Nutrition 0.000 claims 1
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 27
- 150000007513 acids Chemical class 0.000 description 7
- 239000003513 alkali Substances 0.000 description 5
- 239000011701 zinc Substances 0.000 description 5
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 4
- 238000006243 chemical reaction Methods 0.000 description 4
- 150000002148 esters Chemical class 0.000 description 4
- 229910052751 metal Inorganic materials 0.000 description 4
- 239000002184 metal Substances 0.000 description 4
- 150000004702 methyl esters Chemical class 0.000 description 4
- 235000011149 sulphuric acid Nutrition 0.000 description 4
- 239000000725 suspension Substances 0.000 description 4
- 239000002211 L-ascorbic acid Substances 0.000 description 3
- 235000000069 L-ascorbic acid Nutrition 0.000 description 3
- 229910052745 lead Inorganic materials 0.000 description 3
- 239000000047 product Substances 0.000 description 3
- 239000011541 reaction mixture Substances 0.000 description 3
- 239000002904 solvent Substances 0.000 description 3
- 239000001117 sulphuric acid Substances 0.000 description 3
- 229910052725 zinc Inorganic materials 0.000 description 3
- RTZKZFJDLAIYFH-UHFFFAOYSA-N Diethyl ether Chemical compound CCOCC RTZKZFJDLAIYFH-UHFFFAOYSA-N 0.000 description 2
- 150000000996 L-ascorbic acids Chemical class 0.000 description 2
- 238000009833 condensation Methods 0.000 description 2
- 230000005494 condensation Effects 0.000 description 2
- 238000001816 cooling Methods 0.000 description 2
- 125000004435 hydrogen atom Chemical group [H]* 0.000 description 2
- 238000002955 isolation Methods 0.000 description 2
- 238000002844 melting Methods 0.000 description 2
- 230000008018 melting Effects 0.000 description 2
- 238000010992 reflux Methods 0.000 description 2
- KEQXNNJHMWSZHK-UHFFFAOYSA-L 1,3,2,4$l^{2}-dioxathiaplumbetane 2,2-dioxide Chemical compound [Pb+2].[O-]S([O-])(=O)=O KEQXNNJHMWSZHK-UHFFFAOYSA-L 0.000 description 1
- RGHNJXZEOKUKBD-SQOUGZDYSA-N D-gluconic acid Chemical compound OC[C@@H](O)[C@@H](O)[C@H](O)[C@@H](O)C(O)=O RGHNJXZEOKUKBD-SQOUGZDYSA-N 0.000 description 1
- CIWBSHSKHKDKBQ-DUZGATOHSA-N D-isoascorbic acid Chemical compound OC[C@@H](O)[C@H]1OC(=O)C(O)=C1O CIWBSHSKHKDKBQ-DUZGATOHSA-N 0.000 description 1
- RGHNJXZEOKUKBD-QTBDOELSSA-N L-gulonic acid Chemical compound OC[C@H](O)[C@@H](O)[C@H](O)[C@H](O)C(O)=O RGHNJXZEOKUKBD-QTBDOELSSA-N 0.000 description 1
- 229910052924 anglesite Inorganic materials 0.000 description 1
- FFBHFFJDDLITSX-UHFFFAOYSA-N benzyl N-[2-hydroxy-4-(3-oxomorpholin-4-yl)phenyl]carbamate Chemical compound OC1=C(NC(=O)OCC2=CC=CC=C2)C=CC(=C1)N1CCOCC1=O FFBHFFJDDLITSX-UHFFFAOYSA-N 0.000 description 1
- 125000004432 carbon atom Chemical group C* 0.000 description 1
- 238000005837 enolization reaction Methods 0.000 description 1
- 235000010350 erythorbic acid Nutrition 0.000 description 1
- HYBBIBNJHNGZAN-UHFFFAOYSA-N furfural Chemical compound O=CC1=CC=CO1 HYBBIBNJHNGZAN-UHFFFAOYSA-N 0.000 description 1
- 229940026239 isoascorbic acid Drugs 0.000 description 1
- 229910021514 lead(II) hydroxide Inorganic materials 0.000 description 1
- 239000000155 melt Substances 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 239000003960 organic solvent Substances 0.000 description 1
- 238000001556 precipitation Methods 0.000 description 1
- 230000008707 rearrangement Effects 0.000 description 1
- HVTHJRMZXBWFNE-UHFFFAOYSA-J sodium zincate Chemical compound [OH-].[OH-].[OH-].[OH-].[Na+].[Na+].[Zn+2] HVTHJRMZXBWFNE-UHFFFAOYSA-J 0.000 description 1
- 238000004448 titration Methods 0.000 description 1
- 150000003751 zinc Chemical class 0.000 description 1
- 229910021511 zinc hydroxide Inorganic materials 0.000 description 1
- NWONKYPBYAMBJT-UHFFFAOYSA-L zinc sulfate Chemical compound [Zn+2].[O-]S([O-])(=O)=O NWONKYPBYAMBJT-UHFFFAOYSA-L 0.000 description 1
- 229910000368 zinc sulfate Inorganic materials 0.000 description 1
- 239000011686 zinc sulphate Substances 0.000 description 1
- 235000009529 zinc sulphate Nutrition 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D307/00—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom
- C07D307/02—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom not condensed with other rings
- C07D307/34—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom not condensed with other rings having two or three double bonds between ring members or between ring members and non-ring members
- C07D307/56—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom 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
- C07D307/62—Three oxygen atoms, e.g. ascorbic acid
Definitions
- the subject of this invention is a method for I the enolisation of 2-keto-hexonic acids in alkaline medium in the presence; of amphoteric hydroxides of heavy metals, which form compounds with alkalies, as for example, Pb(OH)2 or Zn(OH)2, in water-free solvents.
- the ascorbic acid is deposited in the form of diificultly soluble salts of the amphoteric metals, by which means the isolation of this acid in pure state from the reaction mixture is made possible in suitable manner.
- the method according to the invention is especially suited for the enolisation of difiicultly crystallizing esters" of the Z-ketohexonic acids, from which completely pure ascorbic acids are then obtained.
- Pbor Zn-salts of the ascorbic acid are disintegrated by the action of H2SO4 or H28 in an organic solvent.
- the yield in pure substance is 70-80% of the theory.
- the reaction generally proceeds according to the following scheme:
- the separated ZnSO4 or ZnS is filtered off and the filtrate concentrated in vacuo at 20 C. 6.2 to 6.5 parts of l-ascorbic acid is obtained, that is a yield of 74 to 77% of the theory.
- the product recrystallized from methanol has a melting point of 181 to 185 C.
- the yield of pure substance amounts to 60 to 65% of the theory and its melting point is 180 to hexonic acid by heating them in a water-free lower alcohol with an alkali compound of amphoteric hydroxides of heavy metals selected from the group Pb and Zn treating this precipitate of a metal salt of ascorbic acid with a substance selected from the group consisting of hydrogen sulphide and sulphuric acid, filtering to obtain a filtrate containing soluble ascorbic acid, concentrating the filtrate, and Working up the concentrate to pure ascorbic acid.
- a process for the production of an acid of the ascorbic acid type from a 2-keto-hexonic acid which comprises enolizing esters of Z-ketohexonic acid by heating them in a water-free lower alcohol with an alkali compound of amphoteric hydroxides of heavy metals selected from the group Pb and Zn, treating this precipitate of a metal salt of ascorbic acid with a substance selected from the group consisting of hydrogen sulphide and sulphuric acid, filtering to obtain a filtrate containing soluble ascorbic acid, concentrating the filtrate, and working up the concentrate to pure ascorbic acid.
- a process for the production of an acid of the ascorbic acid type from a 2-keto-hexonic acid which comprises enolizing esters of 2-ketohexonic acid by heating them in a water-free lower alcohol with an alkali compound of amphoteric hydroxides of heavy metals selected from the group Pb and Zn to precipitate a heavy metal salt of ascorbic acid, treating this precipitate with a substance selected from the group consisting of hydrogen sulphide and sulphuric acid, filtering to obtain a filtrate containing soluble ascorbic acid, concentrating the filtrate in vacuo at a low temperature, and working up the concentrate to pure ascorbic acid.
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- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Description
Patented Mar. 25, 1952 PRODUCTION OF AN ACID OF THE ASCORBIC ACID TYPE FROM A Z-KETO-HEXONIC ACID Viktor Ettel, Prague, Czechoslovakia, assignor to Spclek pro chemickou a hutni vyrobu, narodni podnik, also named United Chemical and Metallurgical Works, National Corporation, Prague, Czechoslovakia N Drawing. Application May 10, 1949, Serial No. 92,520. In Czechoslovakia May 13, 1948 3 Claims. 1 It is known that 2-keto-hexonic acids, if necessary their-esters, can be transformed in alkaline or acid media into corresponding acids of the ascorbic acid type of the composition as follows:
00 00 not? H0('; 7 I] l! 0 H00 H00 l H n Ho in OH bmon JHiOH The reaction, by which ascorbic acid is formed from the 2-keto-hexonic acids, occurs by enolisa- The subject of this invention is a method for I the enolisation of 2-keto-hexonic acids in alkaline medium in the presence; of amphoteric hydroxides of heavy metals, which form compounds with alkalies, as for example, Pb(OH)2 or Zn(OH)2, in water-free solvents. The amphoteric heavy metals are used in the form of their alkali compounds of the type Me(ONa)OH (Me=amphoteric metal) in a suspension or solution of water-free solvents. In this way the enolisation takes place very rapidly with heating, namely in the course of few minutes, and with good yield. At the same time the ascorbic acid is deposited in the form of diificultly soluble salts of the amphoteric metals, by which means the isolation of this acid in pure state from the reaction mixture is made possible in suitable manner. The method according to the invention is especially suited for the enolisation of difiicultly crystallizing esters" of the Z-ketohexonic acids, from which completely pure ascorbic acids are then obtained. Pbor Zn-salts of the ascorbic acid are disintegrated by the action of H2SO4 or H28 in an organic solvent. The yield in pure substance is 70-80% of the theory. The reaction generally proceeds according to the following scheme:
tion. This represents substantially the rearrangement of an H-atom on to the neighbouring CO-- group, a double bond according to the scheme I being formed between the relevant C-atoms (the remaining H-atom can be represented by another group, in this case by the OI-I-- group).
As is well known the 2-keto-hexonic acids, if necessary their esters, can be transformed into corresponding ascorbic acids by enolisation in alkaline or acid media. In the enolisation with acids furol and other disintegrating products are produced, which decrease the yield of ascorbic acid and render its isolation difficult. On the other hand the enolisation of methyl esters with alkalis in water-free solvents aiiords much better results, the reaction taking place in shorter time with good yie1d.
about 20% of the theory.
Examples of carrying out the'process 1. 10 parts of methyl ester of the2-ket0-lidonic acid (gulonic acid) are dissolved in 100 parts of water-free methanol and enolized with a suspension 01'' 6 parts of sodium zincate Zn(ONa)OI-I in 50 parts of water-free methanol for ten minutes at a temperature of C. in reflux condensation. By the reaction zinc-l ascorbinate is formed in a yield of' 8i0 to of the theory. Complete precipitation of the zinc salt is obtained by the cooling of the reaction mixture and addition of 50 parts of ether. The slightly yellow coloured deposit of zinc-l-ascorbinate is suctioned ofi, suspended moist in 100 parts of water-free methanol and precipitated with an equivalent amount of H2804. or H23.
The separated ZnSO4 or ZnS is filtered off and the filtrate concentrated in vacuo at 20 C. 6.2 to 6.5 parts of l-ascorbic acid is obtained, that is a yield of 74 to 77% of the theory. The product recrystallized from methanol has a melting point of 181 to 185 C.
2. parts of methyl ester of the 2-keto-dgluconic acid are dissolved in 200 parts of waterfree methanol, enolized with a suspension of Zn(ONa)OH and treated further according to Example 1. The yield of the isoascorbic acid formed amounts to 75 to 78% of the theory. The pure product recrystallized from methanol melts at 173 C.
3. 10 parts of methyl ester of the 2-keto-lidonic acid are dissolved in 100 parts of waterfree methanol and enolized with a suspension of 13 parts of Pb(ONa) OH in 50 parts of waterfree methanol for 15 to minutes at a temperature of 65 C. in reflux condensation. l-ascorbic acid with a yield of 70% of the theory is produced by the enolization, as was established by titration. The separated yellow lead salt is filtered ofi after the cooling of the reaction mixture, suspended still moist in water-free methanol and precipitated with HzS or by addition of an equivalent amount of H2804. The separated PbS or PbSO4, is filtered and the filtrate containing l-ascorbic acid concentrated in vacuo. The yield of pure substance amounts to 60 to 65% of the theory and its melting point is 180 to hexonic acid by heating them in a water-free lower alcohol with an alkali compound of amphoteric hydroxides of heavy metals selected from the group Pb and Zn treating this precipitate of a metal salt of ascorbic acid with a substance selected from the group consisting of hydrogen sulphide and sulphuric acid, filtering to obtain a filtrate containing soluble ascorbic acid, concentrating the filtrate, and Working up the concentrate to pure ascorbic acid.
2. A process for the production of an acid of the ascorbic acid type from a 2-keto-hexonic acid, which comprises enolizing esters of Z-ketohexonic acid by heating them in a water-free lower alcohol with an alkali compound of amphoteric hydroxides of heavy metals selected from the group Pb and Zn, treating this precipitate of a metal salt of ascorbic acid with a substance selected from the group consisting of hydrogen sulphide and sulphuric acid, filtering to obtain a filtrate containing soluble ascorbic acid, concentrating the filtrate, and working up the concentrate to pure ascorbic acid.
3. A process for the production of an acid of the ascorbic acid type from a 2-keto-hexonic acid, which comprises enolizing esters of 2-ketohexonic acid by heating them in a water-free lower alcohol with an alkali compound of amphoteric hydroxides of heavy metals selected from the group Pb and Zn to precipitate a heavy metal salt of ascorbic acid, treating this precipitate with a substance selected from the group consisting of hydrogen sulphide and sulphuric acid, filtering to obtain a filtrate containing soluble ascorbic acid, concentrating the filtrate in vacuo at a low temperature, and working up the concentrate to pure ascorbic acid.
VIKTOR ETTEL.
REFERENCES CITED The following references are of record in the file of this patent:
UNITED STATES PATENTS Number Name Date 2,265,121 Reichstein Dec. 2, 1941 2,443,487 Wenner June 15, 1948 FOREIGN PATENTS Number Country Date 469,157 Great Britain July 20, 1937
Claims (1)
1. A PROCESS FOR THE PRODUCTION OF AN ACID OF THE ASCORBIC ACID TYPE FROM A 2-KETO-HEXONIC ACID, WHICH COMPRISES ENOLIZING ESTERS OF 2-KETOHEXONIC ACID BY HEATING THEM IN A WATER-FREE LOWER ALCOHOL WITH AN ALKALI COMPOUND OF AMPHOTERIC HYDROXIDES OF HEAVY METALS SELECTED FROM THE GROUP PB AND ZN TREATING THIS PRECIPITATE OF A METAL SALT OF ASCORBIC ACID WITH A SUBSTANCE SELECTED FROM THE GROUP CONSISTING OF HYDROGEN SULPHIDE AND SULPHIDE ACID, FILTERING TO OBTAIN A FILTRATE CONTAINING SOLUBLE ASCORBIC ACID, CONCENTRATING THE FILTRATE, AND WORKING UP THE CON CENTRATE TO PURE ASCORBIC ACID,
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CS2590163X | 1948-05-13 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US2590163A true US2590163A (en) | 1952-03-25 |
Family
ID=5458906
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US92520A Expired - Lifetime US2590163A (en) | 1948-05-13 | 1949-05-10 | Production of an acid of the ascorbic acid type from a 2-keto-hexonic acid |
Country Status (1)
| Country | Link |
|---|---|
| US (1) | US2590163A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE1263753B (en) * | 1960-09-12 | 1968-03-21 | Int Minerals & Chem Corp | Process for obtaining crystalline pure sodium isoascorbate monohydrate |
| WO2003018569A1 (en) * | 2001-08-24 | 2003-03-06 | Eastman Chemical Company | Process for ascorbic acids using alkaline earth silicate catalysts |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB469157A (en) * | 1935-06-18 | 1937-07-20 | Tadeus Reichstein | Process for the manufacture of laevo-ascorbic acid |
| US2265121A (en) * | 1933-10-25 | 1941-12-02 | Hoffmann La Roche | Process for the manufacture of levoascorbic acid |
| US2443487A (en) * | 1945-10-27 | 1948-06-15 | Hoffmann La Roche | Synthesis of compounds of the ascorbic acid series |
-
1949
- 1949-05-10 US US92520A patent/US2590163A/en not_active Expired - Lifetime
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2265121A (en) * | 1933-10-25 | 1941-12-02 | Hoffmann La Roche | Process for the manufacture of levoascorbic acid |
| GB469157A (en) * | 1935-06-18 | 1937-07-20 | Tadeus Reichstein | Process for the manufacture of laevo-ascorbic acid |
| US2443487A (en) * | 1945-10-27 | 1948-06-15 | Hoffmann La Roche | Synthesis of compounds of the ascorbic acid series |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE1263753B (en) * | 1960-09-12 | 1968-03-21 | Int Minerals & Chem Corp | Process for obtaining crystalline pure sodium isoascorbate monohydrate |
| WO2003018569A1 (en) * | 2001-08-24 | 2003-03-06 | Eastman Chemical Company | Process for ascorbic acids using alkaline earth silicate catalysts |
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