CA1039749A - PROCESS FOR THE PREPARATION OF .alpha.-DIOL-.gamma.-DIOXO COMPOUNDS - Google Patents
PROCESS FOR THE PREPARATION OF .alpha.-DIOL-.gamma.-DIOXO COMPOUNDSInfo
- Publication number
- CA1039749A CA1039749A CA229,050A CA229050A CA1039749A CA 1039749 A CA1039749 A CA 1039749A CA 229050 A CA229050 A CA 229050A CA 1039749 A CA1039749 A CA 1039749A
- Authority
- CA
- Canada
- Prior art keywords
- diol
- preparation
- process according
- represent
- general formula
- 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
- 238000000034 method Methods 0.000 title claims abstract description 15
- 150000001875 compounds Chemical class 0.000 title claims abstract description 13
- 238000002360 preparation method Methods 0.000 title claims abstract description 11
- 239000012285 osmium tetroxide Substances 0.000 claims abstract description 12
- 229910000489 osmium tetroxide Inorganic materials 0.000 claims abstract description 12
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 11
- XTEGARKTQYYJKE-UHFFFAOYSA-M chlorate Inorganic materials [O-]Cl(=O)=O XTEGARKTQYYJKE-UHFFFAOYSA-M 0.000 claims abstract description 8
- 239000000203 mixture Substances 0.000 claims abstract description 5
- 230000001590 oxidative effect Effects 0.000 claims abstract description 4
- -1 alkaline earth metal chlorate Chemical class 0.000 claims abstract description 3
- 125000004435 hydrogen atom Chemical group [H]* 0.000 claims abstract description 3
- 229910052784 alkaline earth metal Inorganic materials 0.000 claims abstract 2
- 238000006243 chemical reaction Methods 0.000 claims description 6
- 239000007791 liquid phase Substances 0.000 claims description 3
- 239000012442 inert solvent Substances 0.000 claims 1
- 239000007788 liquid Substances 0.000 claims 1
- 238000007363 ring formation reaction Methods 0.000 abstract description 4
- 230000015572 biosynthetic process Effects 0.000 abstract description 3
- 150000002240 furans Chemical class 0.000 abstract description 3
- 239000000543 intermediate Substances 0.000 abstract description 3
- 239000000796 flavoring agent Substances 0.000 abstract description 2
- 235000019634 flavors Nutrition 0.000 abstract description 2
- 238000003786 synthesis reaction Methods 0.000 abstract description 2
- 239000002304 perfume Substances 0.000 abstract 1
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 6
- UHOVQNZJYSORNB-UHFFFAOYSA-N Benzene Chemical compound C1=CC=CC=C1 UHOVQNZJYSORNB-UHFFFAOYSA-N 0.000 description 6
- 239000000758 substrate Substances 0.000 description 5
- FJSKXQVRKZTKSI-UHFFFAOYSA-N 2,3-dimethylfuran Chemical compound CC=1C=COC=1C FJSKXQVRKZTKSI-UHFFFAOYSA-N 0.000 description 4
- RTZKZFJDLAIYFH-UHFFFAOYSA-N Diethyl ether Chemical compound CCOCC RTZKZFJDLAIYFH-UHFFFAOYSA-N 0.000 description 4
- XEKOWRVHYACXOJ-UHFFFAOYSA-N Ethyl acetate Chemical compound CCOC(C)=O XEKOWRVHYACXOJ-UHFFFAOYSA-N 0.000 description 3
- 239000000284 extract Substances 0.000 description 3
- 229910052757 nitrogen Inorganic materials 0.000 description 3
- VKJKEPKFPUWCAS-UHFFFAOYSA-M potassium chlorate Chemical compound [K+].[O-]Cl(=O)=O VKJKEPKFPUWCAS-UHFFFAOYSA-M 0.000 description 3
- 239000002904 solvent Substances 0.000 description 3
- GSNUFIFRDBKVIE-UHFFFAOYSA-N 2,5-dimethylfuran Chemical compound CC1=CC=C(C)O1 GSNUFIFRDBKVIE-UHFFFAOYSA-N 0.000 description 2
- PMZURENOXWZQFD-UHFFFAOYSA-L Sodium Sulfate Chemical compound [Na+].[Na+].[O-]S([O-])(=O)=O PMZURENOXWZQFD-UHFFFAOYSA-L 0.000 description 2
- 238000004821 distillation Methods 0.000 description 2
- 238000000605 extraction Methods 0.000 description 2
- 230000008018 melting Effects 0.000 description 2
- 238000002844 melting Methods 0.000 description 2
- 229910052762 osmium Inorganic materials 0.000 description 2
- SYQBFIAQOQZEGI-UHFFFAOYSA-N osmium atom Chemical compound [Os] SYQBFIAQOQZEGI-UHFFFAOYSA-N 0.000 description 2
- 238000011084 recovery Methods 0.000 description 2
- VZGDMQKNWNREIO-UHFFFAOYSA-N tetrachloromethane Chemical compound ClC(Cl)(Cl)Cl VZGDMQKNWNREIO-UHFFFAOYSA-N 0.000 description 2
- OJVAMHKKJGICOG-UHFFFAOYSA-N 2,5-hexanedione Chemical compound CC(=O)CCC(C)=O OJVAMHKKJGICOG-UHFFFAOYSA-N 0.000 description 1
- 150000001298 alcohols Chemical class 0.000 description 1
- 238000010504 bond cleavage reaction Methods 0.000 description 1
- 230000003197 catalytic effect Effects 0.000 description 1
- 238000002425 crystallisation Methods 0.000 description 1
- 230000008025 crystallization Effects 0.000 description 1
- 238000002329 infrared spectrum Methods 0.000 description 1
- 238000000655 nuclear magnetic resonance spectrum Methods 0.000 description 1
- 239000007800 oxidant agent Substances 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 239000011541 reaction mixture Substances 0.000 description 1
- 230000007017 scission Effects 0.000 description 1
- 229910052938 sodium sulfate Inorganic materials 0.000 description 1
- 235000011152 sodium sulphate Nutrition 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 238000000935 solvent evaporation Methods 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C49/00—Ketones; Ketenes; Dimeric ketenes; Ketonic chelates
- C07C49/04—Saturated compounds containing keto groups bound to acyclic carbon atoms
- C07C49/17—Saturated compounds containing keto groups bound to acyclic carbon atoms containing hydroxy groups
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C45/00—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds
- C07C45/56—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds from heterocyclic compounds
- C07C45/57—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds from heterocyclic compounds with oxygen as the only heteroatom
- C07C45/59—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds from heterocyclic compounds with oxygen as the only heteroatom in five-membered rings
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
- Low-Molecular Organic Synthesis Reactions Using Catalysts (AREA)
Abstract
ABSTRACT OF THE DISCLOSURE:
The invention relates to a process for the preparation of -diol- -dioxo compounds having the general formula:
in which R1 and R4 which may be identical or different, each represent a lower alkyl radical and R2 and R3 each represent a hydrogen atom, comprising reacting a compound having the general formula:
The invention relates to a process for the preparation of -diol- -dioxo compounds having the general formula:
in which R1 and R4 which may be identical or different, each represent a lower alkyl radical and R2 and R3 each represent a hydrogen atom, comprising reacting a compound having the general formula:
Description
~o39749 ~
The present invention relates to a process for the preparation of ~-diol-~-dioxo compounds having the general ; formula Rl-CO-l -- C -Co-R4 , .. .
.. 1H 1H
in which R and R4, which may be identical or different, each represent a lower alkyl radical and R2 and R3 each represent a hydrogen atom, which process comprises reacting a compound having the general formula:
R ~ R4 .;,,' ' , in which R1, R2, R3, R4 have the abovesaid meanings, with an '~4~i oxidizing mixture consisting of osmium tetroxide and an alkaline or alkaline-earth chlorate, in the presence of water. The ~ ~-diol-~-dioxo compounds according to the present invention 3 are useful syntesis intermediates, for instance in the prepara-tion via cyclization of furane derivatives, some of which may be employed a9 flavorants and per~umes ~see G. B~chi, E. Demole and F. Thomas, I. Org. Chem. 38, 123 (1973) and L. Re, B. Maurer, ; ~. Ohlaff, Helv. 56, 1882 ~1973)). Compared to the known methods of preparation of the aforesaid ~-diol-~-dioxo compounds, the method according to the invention has the advantage of being .
, not only cheaper but also simpler from an operative point of view.
Furthermore, in the preparation of furane derivatives through cyclization, the method of synthesis of the ~-diol-~
dioxo compounds according to the invention is particularly nteresting since it enables the cyclization, through known 1039749 :
operations (see the already cited G. B~chi et al.) of the -~
aqueous mixture obtained at the end of the reaction after ~1 recovery of osmium tetroxide, without isolating the intermediate compound.
According to the invention, the oxidizing agent comprises osmium tetroxide. This compound can be used in cata-lytic amounts preferably of at least 20 mg per g of substrate since it is continuously regenerated by the chlorate through an oxidative scission of the adduct between osmium tetroxide and substrate. Chlorate must, therefore, be also present in at least stoichiometric amounts.
In accordance with the present invention, osmium , tetroxide may be recovered at the end of the reaction by dragging under a nitrogen stream, the osmium tetroxide being caught A`i in a trap containing the starting product with which it forms a non-volatile adduct, or by selective extraction by means of a suitable solvent such as CC14, benzene, Et2O and subsequent solvent evaporation after having add the extract to the starting products, or also by another techniques well known to any man ~1 20 skilled in the art.
The oxidation reaction i5 carried out in an aqueous environment at a temperature ranging from 0 to 100C, preferably ~ ~ .
from ~25 to ~50C and under pressure to maintain the system in the liquid phase. When use is made of a water unsoluble solid ` substrates, use is preferably made of an inert usual solvent j either miscible with water for dissolving, at least partially, 7 , the substrate (THF, alcohols) or immiscible with water for dissolving, also only partially, both substrate and osmium ' tetroxide (CC14, Et2O, benzene).
The present invention will be better understood ~ with reference to the following non~restrictive example -~ EXAMPLE
; - 2 -`',~,~ . ' ''" '" ' ~Q;~9749 Preparation of eritro-3,4-dihydroxy~xan~2/5-dione from 2,5-dimethylfurane:
To 30 ml of water were added 2.80 g (22~8 mmo~les) of potassium chlorate, 50.8 mg (0.20 mmole) of osmium tetroxide and 0.96 g (lO.0 mmoles) of 2.5-dimethyl furane. The mixture was stirred over 17 hours at room temperature in a closed vessel. The water insoluble liquid phase was extracted with dimethylfurane. To recover osmium tetroxide, nitrogen was bubbled through the reaction vessel connected, at its outlet, to a trap provided with a porous septum immersed in dimethyl-furane and cooled. The osmium tetroxide, dragged by nitrogen, was caugth through formation of dimethylfurane adduct, that is not volatile. The content of the trap could be used, after addition of water and potassium chlorate, for another prepara-tion. Alternatively the osmium tetroxide recovery could be carried out by means of a selective extraction t;ereof with ~i CCl4 followed by the addition of dimethylfurane to the extract so as to form an adduct, and by a solvent distillation. The ' distillation residue could then be used after addition of water and potassium chlorate, for another preparation.
The reaction mixture was dry evaporated under a 15 mmHg vacuum at room temperature. The re~idue was extracted se-veral times with ethyl acetate and the extracts, joined ; together, were dried (anhydrous sodium sulphate) and dry evapo-rated under vacuum. 1.26 g. of a white crystalline product were obtained having a melting point of 46 - 49C, from which ' was obtained 0.89 g (61% yield) of pure eritro-3,4-dihydroxy-;~. hexan-2,5 dione, via chlorofom-ligroin crystallization, it having a melting point of 60-62 C and infrared and NMR
spectra agreeing the known ones (G. B~chi et al.) ,. ~, .
$
` ~' ' ' -
The present invention relates to a process for the preparation of ~-diol-~-dioxo compounds having the general ; formula Rl-CO-l -- C -Co-R4 , .. .
.. 1H 1H
in which R and R4, which may be identical or different, each represent a lower alkyl radical and R2 and R3 each represent a hydrogen atom, which process comprises reacting a compound having the general formula:
R ~ R4 .;,,' ' , in which R1, R2, R3, R4 have the abovesaid meanings, with an '~4~i oxidizing mixture consisting of osmium tetroxide and an alkaline or alkaline-earth chlorate, in the presence of water. The ~ ~-diol-~-dioxo compounds according to the present invention 3 are useful syntesis intermediates, for instance in the prepara-tion via cyclization of furane derivatives, some of which may be employed a9 flavorants and per~umes ~see G. B~chi, E. Demole and F. Thomas, I. Org. Chem. 38, 123 (1973) and L. Re, B. Maurer, ; ~. Ohlaff, Helv. 56, 1882 ~1973)). Compared to the known methods of preparation of the aforesaid ~-diol-~-dioxo compounds, the method according to the invention has the advantage of being .
, not only cheaper but also simpler from an operative point of view.
Furthermore, in the preparation of furane derivatives through cyclization, the method of synthesis of the ~-diol-~
dioxo compounds according to the invention is particularly nteresting since it enables the cyclization, through known 1039749 :
operations (see the already cited G. B~chi et al.) of the -~
aqueous mixture obtained at the end of the reaction after ~1 recovery of osmium tetroxide, without isolating the intermediate compound.
According to the invention, the oxidizing agent comprises osmium tetroxide. This compound can be used in cata-lytic amounts preferably of at least 20 mg per g of substrate since it is continuously regenerated by the chlorate through an oxidative scission of the adduct between osmium tetroxide and substrate. Chlorate must, therefore, be also present in at least stoichiometric amounts.
In accordance with the present invention, osmium , tetroxide may be recovered at the end of the reaction by dragging under a nitrogen stream, the osmium tetroxide being caught A`i in a trap containing the starting product with which it forms a non-volatile adduct, or by selective extraction by means of a suitable solvent such as CC14, benzene, Et2O and subsequent solvent evaporation after having add the extract to the starting products, or also by another techniques well known to any man ~1 20 skilled in the art.
The oxidation reaction i5 carried out in an aqueous environment at a temperature ranging from 0 to 100C, preferably ~ ~ .
from ~25 to ~50C and under pressure to maintain the system in the liquid phase. When use is made of a water unsoluble solid ` substrates, use is preferably made of an inert usual solvent j either miscible with water for dissolving, at least partially, 7 , the substrate (THF, alcohols) or immiscible with water for dissolving, also only partially, both substrate and osmium ' tetroxide (CC14, Et2O, benzene).
The present invention will be better understood ~ with reference to the following non~restrictive example -~ EXAMPLE
; - 2 -`',~,~ . ' ''" '" ' ~Q;~9749 Preparation of eritro-3,4-dihydroxy~xan~2/5-dione from 2,5-dimethylfurane:
To 30 ml of water were added 2.80 g (22~8 mmo~les) of potassium chlorate, 50.8 mg (0.20 mmole) of osmium tetroxide and 0.96 g (lO.0 mmoles) of 2.5-dimethyl furane. The mixture was stirred over 17 hours at room temperature in a closed vessel. The water insoluble liquid phase was extracted with dimethylfurane. To recover osmium tetroxide, nitrogen was bubbled through the reaction vessel connected, at its outlet, to a trap provided with a porous septum immersed in dimethyl-furane and cooled. The osmium tetroxide, dragged by nitrogen, was caugth through formation of dimethylfurane adduct, that is not volatile. The content of the trap could be used, after addition of water and potassium chlorate, for another prepara-tion. Alternatively the osmium tetroxide recovery could be carried out by means of a selective extraction t;ereof with ~i CCl4 followed by the addition of dimethylfurane to the extract so as to form an adduct, and by a solvent distillation. The ' distillation residue could then be used after addition of water and potassium chlorate, for another preparation.
The reaction mixture was dry evaporated under a 15 mmHg vacuum at room temperature. The re~idue was extracted se-veral times with ethyl acetate and the extracts, joined ; together, were dried (anhydrous sodium sulphate) and dry evapo-rated under vacuum. 1.26 g. of a white crystalline product were obtained having a melting point of 46 - 49C, from which ' was obtained 0.89 g (61% yield) of pure eritro-3,4-dihydroxy-;~. hexan-2,5 dione, via chlorofom-ligroin crystallization, it having a melting point of 60-62 C and infrared and NMR
spectra agreeing the known ones (G. B~chi et al.) ,. ~, .
$
` ~' ' ' -
Claims (6)
1. Process for the preparation of .alpha.-diol-?-dioxo compounds having the general formula:
in which R1 and R4 which may be identical or different, each represent a lower alkyl radical and R2 and R3 each represent a hydrogen atom, which process comprises reacting a compound having the general formula wherein R1, R2, R3, R4 have the above meanings with an oxidizing mixture consisting of osmium tetroxide and an alkaline or alkaline-earth metal chlorate in the presence of water.
in which R1 and R4 which may be identical or different, each represent a lower alkyl radical and R2 and R3 each represent a hydrogen atom, which process comprises reacting a compound having the general formula wherein R1, R2, R3, R4 have the above meanings with an oxidizing mixture consisting of osmium tetroxide and an alkaline or alkaline-earth metal chlorate in the presence of water.
2. Process according to claim 1, characterized in that the reaction is carried out at a temperature of from 0 to 100°C.
3. Process according to claim 3, characterized in that the reaction is carried out at a temperature of from +25 to +50°C.
4. Process according to claim 1, characterized in that the reaction is carried out at a pressure under which the liquid system is in the liquid phase.
5. Process according to claim 1, characterized in that the water is added with an inert solvent.
6. Process according to claim 1, further comprising recovering osmium tetroxide.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| IT23896/74A IT1014988B (en) | 1974-06-12 | 1974-06-12 | PROCESS FOR THE PREPARATION OF ALPHA DIOL RANGE DIOSSO COMPOUNDS |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1039749A true CA1039749A (en) | 1978-10-03 |
Family
ID=11210711
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA229,050A Expired CA1039749A (en) | 1974-06-12 | 1975-06-11 | PROCESS FOR THE PREPARATION OF .alpha.-DIOL-.gamma.-DIOXO COMPOUNDS |
Country Status (18)
| Country | Link |
|---|---|
| JP (1) | JPS5839137B2 (en) |
| BE (1) | BE830109A (en) |
| CA (1) | CA1039749A (en) |
| CH (1) | CH605521A5 (en) |
| CS (1) | CS203002B2 (en) |
| DD (1) | DD118069A5 (en) |
| DK (1) | DK264675A (en) |
| FR (1) | FR2279708A1 (en) |
| GB (1) | GB1505667A (en) |
| HU (1) | HU172080B (en) |
| IL (1) | IL47459A (en) |
| IT (1) | IT1014988B (en) |
| LU (1) | LU72706A1 (en) |
| NL (1) | NL7507042A (en) |
| NO (1) | NO141512C (en) |
| SE (1) | SE422199B (en) |
| YU (1) | YU132375A (en) |
| ZA (1) | ZA753469B (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE3067027D1 (en) * | 1980-01-11 | 1984-04-19 | Ici Plc | Process for the preparation of 1,4-dialkylbut-2-ene-1,4-diones |
| JPH0268150U (en) * | 1988-11-10 | 1990-05-23 |
-
1974
- 1974-06-12 IT IT23896/74A patent/IT1014988B/en active
-
1975
- 1975-05-23 YU YU01323/75A patent/YU132375A/en unknown
- 1975-05-28 ZA ZA00753469A patent/ZA753469B/en unknown
- 1975-06-05 FR FR7517602A patent/FR2279708A1/en active Granted
- 1975-06-09 CS CS754025A patent/CS203002B2/en unknown
- 1975-06-10 LU LU72706A patent/LU72706A1/xx unknown
- 1975-06-11 CH CH755775A patent/CH605521A5/xx not_active IP Right Cessation
- 1975-06-11 IL IL47459A patent/IL47459A/en unknown
- 1975-06-11 HU HU75SA00002801A patent/HU172080B/en unknown
- 1975-06-11 NO NO752080A patent/NO141512C/en unknown
- 1975-06-11 DK DK264675A patent/DK264675A/en not_active Application Discontinuation
- 1975-06-11 CA CA229,050A patent/CA1039749A/en not_active Expired
- 1975-06-11 BE BE157224A patent/BE830109A/en not_active IP Right Cessation
- 1975-06-12 GB GB25278/75A patent/GB1505667A/en not_active Expired
- 1975-06-12 DD DD186609A patent/DD118069A5/xx unknown
- 1975-06-12 NL NL7507042A patent/NL7507042A/en not_active Application Discontinuation
- 1975-06-12 SE SE7506763A patent/SE422199B/en unknown
- 1975-06-12 JP JP50070241A patent/JPS5839137B2/en not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| NO141512C (en) | 1980-03-26 |
| FR2279708A1 (en) | 1976-02-20 |
| JPS5111701A (en) | 1976-01-30 |
| JPS5839137B2 (en) | 1983-08-27 |
| DD118069A5 (en) | 1976-02-12 |
| IT1014988B (en) | 1977-04-30 |
| NO141512B (en) | 1979-12-17 |
| GB1505667A (en) | 1978-03-30 |
| DE2526050A1 (en) | 1975-12-18 |
| CS203002B2 (en) | 1981-02-27 |
| LU72706A1 (en) | 1975-10-08 |
| ZA753469B (en) | 1976-05-26 |
| SE422199B (en) | 1982-02-22 |
| DE2526050B2 (en) | 1977-04-21 |
| FR2279708B1 (en) | 1978-05-19 |
| AU8145675A (en) | 1976-11-25 |
| NL7507042A (en) | 1975-12-16 |
| IL47459A (en) | 1979-01-31 |
| BE830109A (en) | 1975-10-01 |
| NO752080L (en) | 1975-12-15 |
| HU172080B (en) | 1978-05-28 |
| SE7506763L (en) | 1975-12-15 |
| DK264675A (en) | 1975-12-13 |
| YU132375A (en) | 1982-02-28 |
| IL47459A0 (en) | 1975-12-31 |
| CH605521A5 (en) | 1978-09-29 |
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