IE45643B1 - Process for the preparation of 6,6'-oxy bis (4-halo-2h-pyran-3(6h)-ones) and their use in preparing gamma-pyrones - Google Patents
Process for the preparation of 6,6'-oxy bis (4-halo-2h-pyran-3(6h)-ones) and their use in preparing gamma-pyronesInfo
- Publication number
- IE45643B1 IE45643B1 IE585/79A IE58579A IE45643B1 IE 45643 B1 IE45643 B1 IE 45643B1 IE 585/79 A IE585/79 A IE 585/79A IE 58579 A IE58579 A IE 58579A IE 45643 B1 IE45643 B1 IE 45643B1
- Authority
- IE
- Ireland
- Prior art keywords
- pyrones
- pyran
- gamma
- formula
- compound
- Prior art date
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D309/00—Heterocyclic compounds containing six-membered rings having one oxygen atom as the only ring hetero atom, not condensed with other rings
- C07D309/32—Heterocyclic compounds containing six-membered rings having one oxygen atom as the only ring hetero atom, not condensed with other rings having two double bonds between ring members or between ring members and non-ring members
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D309/00—Heterocyclic compounds containing six-membered rings having one oxygen atom as the only ring hetero atom, not condensed with other rings
- C07D309/34—Heterocyclic compounds containing six-membered rings having one oxygen atom as the only ring hetero atom, not condensed with other rings having three or more double bonds between ring members or between ring members and non-ring members
- C07D309/36—Heterocyclic compounds containing six-membered rings having one oxygen atom as the only ring hetero atom, not condensed with other rings having three or more double bonds between ring members or between ring members and non-ring members with oxygen atoms directly attached to ring carbon atoms
- C07D309/40—Oxygen atoms attached in positions 3 and 4, e.g. maltol
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Pyrane Compounds (AREA)
- Pyridine Compounds (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
- Cosmetics (AREA)
- Plural Heterocyclic Compounds (AREA)
- Furan Compounds (AREA)
- Saccharide Compounds (AREA)
- Transforming Electric Information Into Light Information (AREA)
- Picture Signal Circuits (AREA)
- Low-Molecular Organic Synthesis Reactions Using Catalysts (AREA)
- Nitrogen Condensed Heterocyclic Rings (AREA)
- Processing Of Color Television Signals (AREA)
- Pharmaceuticals Containing Other Organic And Inorganic Compounds (AREA)
- Heterocyclic Carbon Compounds Containing A Hetero Ring Having Oxygen Or Sulfur (AREA)
- Nitrogen And Oxygen Or Sulfur-Condensed Heterocyclic Ring Systems (AREA)
- Seasonings (AREA)
- Agricultural Chemicals And Associated Chemicals (AREA)
- Control Of El Displays (AREA)
Abstract
The gamma-pyrones of formula I in which the symbols have the meaning given in Claim 1 are obtained by a simple and economic "one-pot" process by reaction of a furfuryl alcohol of formula III with at least 2 equivalents of a halogenated oxidising agent, in aqueous solution at a temperature of between -50 DEG and +50 DEG C, and then the reaction mixture is heated until hydrolysis of the intermediate formed is virtually complete. The gamma-pyrones obtained can be used as products which enhance flavour and fragrance in food and cosmetic preparations.
Description
This invention relates to novel 6,6'-oxy bis[4-halo2H-pyran-3(6H)-ones] , a process for their production and a process for their further conversation to gamma-pyrones, particularly to maltol (3-hydroxy-2-mathyl-4H-pyran~4-one) and related compounds.
Thus according to the invention there are provided novel compounds of the general formula: wherein R is hydrogen, alkyl of 1 to 4 carbon atoms, phenyl 10 or benzyl; and X is chlorine or bromine.
Such dimers are prepared by dehydration of a 4-halodihydropyran of the general formula: (II) I 3 6 4 3 where R and X are as defined above, by heating under vacuum. 4-Halo-dihydropyrans of formula (II) are described and claimed in Patent Specification No. 45644 of even date.
Hydrolysis of the 6,6'-oxybis[4-halogeno-2H-pyran-3(6H)5 one] of formula (I), by heating an aqueous solution until hydrolysis is substantially complete yields a gamma-pyrone of the formula: where R is as previously defined.
The preparation of the novel compounds of the invention and their conversion to gamma-pyrones is illustrated by the following Examples.
Example 1 4-Bromo-6-hydroxy-2-methyl-2H-pyran-3(6H)-one was heated under vacuum for 16 hours at 40°C. The resulting oily solid was crystallised from isopropyl alcohol to yield 6,6'-oxybis [4-bromo-2-methyl-2H-pyran-3(6H)-one] , mp 125°C.
Example 2 The method of Example 1 may be repeated starting with a compound of the formula to yield a compound of the formula wherein R is hydrogen, ethyl, propyl, butyl, phenyl or 5 benzyl; X is bromine or chlorine.
R X M.P. (°C.) CH3 Cl 177-179 CH2CH3 Cl 132-135 Example 3 a compound of the formula wherein R is hydrogen, methyl, ethyl, propyl, butyl, phenyl 3 6 4 3 - 5 or benzyl and X is bromine or chlorine is refluxed for about 5 hours in 35% phosphoric acid to yield a compound of the formula R wherein R is as defined above. - 6 ZJ i) Ο ‘, υ
Claims (4)
1. CIAIMS;1. A compound of the general formula wherein R is hydrogen, alkyl of 1 to 4 carbon atoms, phenyl 5 or benzyl; and X is chlorine or bromine.
2. A process for preparing a compound of the general formula wherein R is hydrogen, alkyl of 1 to 4 carbon atoms, phenyl 10 or benzyl; X is chlorine or bromine which comprises dehydrating under vacuum a compound of the general formula - 7 45643
3. A process for preparing a gamma-pyrone of the general formula which comprises heating in aqueous solution at 70-160°C 5 until hydrolysis is substantially complete a compound of the formula wherein R is hydrogen, alkyl of 1 to 4 carbon atoms, phenyl or benzyl and X is chlorine or bromine. 10
4. A process as claimed in claim 2 or 3 substantially as hereinbefore described with reference to the Examples.
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US71090176A | 1976-08-02 | 1976-08-02 | |
US05/721,885 US4082717A (en) | 1976-08-02 | 1976-09-09 | Preparation of gamma-pyrones |
IE1587/77A IE45641B1 (en) | 1976-08-02 | 1977-07-29 | Process for the preparation of gamma-pyrones |
Publications (2)
Publication Number | Publication Date |
---|---|
IE790585L IE790585L (en) | 1978-02-02 |
IE45643B1 true IE45643B1 (en) | 1982-10-20 |
Family
ID=27108548
Family Applications (5)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
IE587/79A IE45645B1 (en) | 1976-08-02 | 1977-07-29 | Process for the preparation of 6-alkoxy and 6-acyloxy-4-halo-2h-pyrones and their use in the synthesis of gamma-pyrones |
IE1587/77A IE45641B1 (en) | 1976-08-02 | 1977-07-29 | Process for the preparation of gamma-pyrones |
IE584/79A IE45642B1 (en) | 1976-08-02 | 1977-07-29 | Process for the preparation of 6-hydroxy-2h-pyran-3(6h)-ones useful in the synthesis of gamma-pyrones |
IE585/79A IE45643B1 (en) | 1976-08-02 | 1977-07-29 | Process for the preparation of 6,6'-oxy bis (4-halo-2h-pyran-3(6h)-ones) and their use in preparing gamma-pyrones |
IE586/79A IE45644B1 (en) | 1976-08-02 | 1977-07-29 | Process for the preparation of 4-halo-6-hydroxy-2h-pyran-3(6h)-ones and their use in the synthesis of gamma-pyrones |
Family Applications Before (3)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
IE587/79A IE45645B1 (en) | 1976-08-02 | 1977-07-29 | Process for the preparation of 6-alkoxy and 6-acyloxy-4-halo-2h-pyrones and their use in the synthesis of gamma-pyrones |
IE1587/77A IE45641B1 (en) | 1976-08-02 | 1977-07-29 | Process for the preparation of gamma-pyrones |
IE584/79A IE45642B1 (en) | 1976-08-02 | 1977-07-29 | Process for the preparation of 6-hydroxy-2h-pyran-3(6h)-ones useful in the synthesis of gamma-pyrones |
Family Applications After (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
IE586/79A IE45644B1 (en) | 1976-08-02 | 1977-07-29 | Process for the preparation of 4-halo-6-hydroxy-2h-pyran-3(6h)-ones and their use in the synthesis of gamma-pyrones |
Country Status (36)
Country | Link |
---|---|
JP (7) | JPS5318578A (en) |
AR (1) | AR216080A1 (en) |
AT (3) | AT362790B (en) |
BE (1) | BE855965A (en) |
BG (4) | BG28849A3 (en) |
BR (1) | BR7703970A (en) |
CA (3) | CA1095921A (en) |
CH (4) | CH625798A5 (en) |
CS (3) | CS203921B2 (en) |
DD (1) | DD132494A5 (en) |
DE (3) | DE2728499C2 (en) |
DK (4) | DK153483C (en) |
EG (1) | EG13080A (en) |
ES (5) | ES459994A1 (en) |
FI (6) | FI72722C (en) |
FR (1) | FR2372821A1 (en) |
GB (5) | GB1538371A (en) |
GR (1) | GR68938B (en) |
HK (5) | HK30381A (en) |
HU (4) | HU186026B (en) |
IE (5) | IE45645B1 (en) |
IT (1) | IT1106258B (en) |
LU (1) | LU77600A1 (en) |
MX (1) | MX4597E (en) |
MY (3) | MY8100287A (en) |
NL (5) | NL170955C (en) |
NO (7) | NO150561C (en) |
NZ (1) | NZ184342A (en) |
PH (5) | PH13557A (en) |
PL (4) | PL115496B1 (en) |
PT (1) | PT66694B (en) |
RO (4) | RO78951A2 (en) |
SE (6) | SE433079B (en) |
SU (2) | SU955859A3 (en) |
TR (1) | TR19652A (en) |
YU (4) | YU40166B (en) |
Families Citing this family (14)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CA1095921A (en) | 1976-08-02 | 1981-02-17 | Thomas M. Brennan | Preparation of gamma-pyrones |
FR2402654A1 (en) * | 1977-09-12 | 1979-04-06 | Shinetsu Chemical Co | Tetra:hydro-pyranone derivs. - useful as intermediates for cpds. used as food flavours |
JPS5444675A (en) * | 1977-09-12 | 1979-04-09 | Shin Etsu Chem Co Ltd | Production of 3-hydroxy-4-pyrone analog |
JPS5741226U (en) * | 1980-08-20 | 1982-03-05 | ||
JPS59135008U (en) * | 1983-02-28 | 1984-09-10 | 松下電工株式会社 | Distribution board device |
JPS6050245A (en) * | 1983-08-29 | 1985-03-19 | Nissan Motor Co Ltd | Fuel injection device in internal-combustion engine |
JPH0226945Y2 (en) * | 1985-09-11 | 1990-07-20 | ||
JP2586607B2 (en) * | 1987-10-30 | 1997-03-05 | 日産化学工業株式会社 | Production method of optically active alcohol |
TWI404533B (en) * | 2007-03-28 | 2013-08-11 | Apotex Technologies Inc | Fluorinated derivatives of deferiprone |
UA102254C2 (en) | 2008-04-25 | 2013-06-25 | Апотекс Технолоджис Инк. | Normal;heading 1;heading 2;heading 3;LIQUID FORMULATION FOR DEFERIPRONE WITH PALATABLE TASTE |
CN102712591B (en) | 2009-07-03 | 2014-06-25 | 阿普泰克斯科技公司 | Fluorinated derivatives of 3-hydroxypyridin-4-ones |
WO2017168309A1 (en) * | 2016-03-29 | 2017-10-05 | Dr. Reddy’S Laboratories Limited | Process for preparation of eribulin and intermediates thereof |
CN108609456B (en) * | 2016-12-13 | 2021-03-12 | 奥的斯电梯公司 | Openable expansion panel and elevator suspended ceiling, elevator car and elevator system with same |
CN111606879A (en) * | 2020-05-25 | 2020-09-01 | 安徽金禾实业股份有限公司 | Method for preparing 2-hydroxymethyl-3-alkoxy-4H-pyran-4-ketone by one-pot method |
Family Cites Families (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3491122A (en) * | 1966-09-14 | 1970-01-20 | Monsanto Co | Synthesis of 4-pyrones |
US3547912A (en) * | 1968-07-29 | 1970-12-15 | American Home Prod | Derivatives of 2h-pyran-3(6h)-ones and preparation thereof |
JPS5145565B1 (en) * | 1968-10-12 | 1976-12-04 | ||
US3621063A (en) * | 1968-12-24 | 1971-11-16 | Monsanto Co | Unsaturated acyclic ketones |
US3832357A (en) * | 1971-05-26 | 1974-08-27 | Daicel Ltd | Process for preparation of 3-hydroxy-2-alkyl-4-pyrone |
JPS5212166A (en) * | 1975-07-17 | 1977-01-29 | Tatsuya Shono | Process for preparation of 4-pyron derivatives |
IE42789B1 (en) * | 1975-08-28 | 1980-10-22 | Pfizer | Preparation of gamma-pyrones |
CA1095921A (en) * | 1976-08-02 | 1981-02-17 | Thomas M. Brennan | Preparation of gamma-pyrones |
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1977
- 1977-06-06 CA CA279,922A patent/CA1095921A/en not_active Expired
- 1977-06-08 NZ NZ184342A patent/NZ184342A/en unknown
- 1977-06-09 GR GR53666A patent/GR68938B/el unknown
- 1977-06-13 YU YU1469/77A patent/YU40166B/en unknown
- 1977-06-15 MX MX775807U patent/MX4597E/en unknown
- 1977-06-16 SE SE7707035A patent/SE433079B/en not_active IP Right Cessation
- 1977-06-16 JP JP7157277A patent/JPS5318578A/en active Granted
- 1977-06-17 PH PH19887A patent/PH13557A/en unknown
- 1977-06-20 BR BR7703970A patent/BR7703970A/en unknown
- 1977-06-21 FI FI771934A patent/FI72722C/en not_active IP Right Cessation
- 1977-06-21 NL NLAANVRAGE7706811,A patent/NL170955C/en not_active IP Right Cessation
- 1977-06-21 BE BE1008209A patent/BE855965A/en not_active IP Right Cessation
- 1977-06-22 PT PT66694A patent/PT66694B/en unknown
- 1977-06-22 DE DE2728499A patent/DE2728499C2/en not_active Expired
- 1977-06-22 DE DE2760221A patent/DE2760221C2/de not_active Expired
- 1977-06-22 LU LU77600A patent/LU77600A1/xx unknown
- 1977-06-22 NO NO772193A patent/NO150561C/en unknown
- 1977-06-22 EG EG371/77A patent/EG13080A/en active
- 1977-06-22 DE DE2760220A patent/DE2760220C2/de not_active Expired
- 1977-06-22 DK DK276177A patent/DK153483C/en active
- 1977-06-22 CH CH765877A patent/CH625798A5/en not_active IP Right Cessation
- 1977-06-22 ES ES459994A patent/ES459994A1/en not_active Expired
- 1977-06-22 AT AT0440477A patent/AT362790B/en not_active IP Right Cessation
- 1977-06-22 TR TR19652A patent/TR19652A/en unknown
- 1977-06-23 DD DD7700199657A patent/DD132494A5/en not_active IP Right Cessation
- 1977-06-23 AR AR268164A patent/AR216080A1/en active
- 1977-06-23 FR FR7719250A patent/FR2372821A1/en active Granted
- 1977-06-23 IT IT49950/77A patent/IT1106258B/en active
- 1977-07-14 BG BG036892A patent/BG28849A3/en unknown
- 1977-07-14 CS CS774705A patent/CS203921B2/en unknown
- 1977-07-14 BG BG042608A patent/BG29136A3/en unknown
- 1977-07-14 BG BG7942607A patent/BG28989A4/en unknown
- 1977-07-14 BG BG7742606A patent/BG28988A4/en unknown
- 1977-07-20 RO RO7799825A patent/RO78951A2/en unknown
- 1977-07-20 RO RO7799826A patent/RO78952A/en unknown
- 1977-07-20 RO RO7799830A patent/RO78953A/en unknown
- 1977-07-20 RO RO7791106A patent/RO74367A/en unknown
- 1977-07-21 SU SU772508256A patent/SU955859A3/en active
- 1977-07-21 GB GB30759/77A patent/GB1538371A/en not_active Expired
- 1977-07-21 HU HU82156A patent/HU186026B/en unknown
- 1977-07-21 HU HU82157A patent/HU185687B/en unknown
- 1977-07-21 HU HU82155A patent/HU185686B/en unknown
- 1977-07-21 PL PL1977215007A patent/PL115496B1/en unknown
- 1977-07-21 PL PL21500877A patent/PL215008A1/en unknown
- 1977-07-21 GB GB4242/78A patent/GB1538374A/en not_active Expired
- 1977-07-21 PL PL1977199798A patent/PL115586B1/en unknown
- 1977-07-21 PL PL1977215006A patent/PL115497B1/en unknown
- 1977-07-21 GB GB4243/78A patent/GB1538375A/en not_active Expired
- 1977-07-21 GB GB4240/78A patent/GB1538372A/en not_active Expired
- 1977-07-21 GB GB4241/78A patent/GB1538373A/en not_active Expired
- 1977-07-21 HU HU77PI584A patent/HU180040B/en unknown
- 1977-07-29 IE IE587/79A patent/IE45645B1/en not_active IP Right Cessation
- 1977-07-29 IE IE1587/77A patent/IE45641B1/en not_active IP Right Cessation
- 1977-07-29 IE IE584/79A patent/IE45642B1/en not_active IP Right Cessation
- 1977-07-29 IE IE585/79A patent/IE45643B1/en not_active IP Right Cessation
- 1977-07-29 IE IE586/79A patent/IE45644B1/en not_active IP Right Cessation
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1978
- 1978-02-03 PH PH20746A patent/PH13926A/en unknown
- 1978-02-03 PH PH20745A patent/PH15185A/en unknown
- 1978-05-25 JP JP6281778A patent/JPS5436266A/en active Pending
- 1978-05-25 JP JP6281978A patent/JPS5436268A/en active Pending
- 1978-05-25 JP JP6282178A patent/JPS5436270A/en active Granted
- 1978-05-25 JP JP53062820A patent/JPS5814433B2/en not_active Expired
- 1978-05-25 JP JP6282278A patent/JPS5436271A/en active Granted
- 1978-05-25 JP JP6281878A patent/JPS5436267A/en active Granted
- 1978-06-07 CS CS783706A patent/CS203923B2/en unknown
- 1978-06-07 CS CS783705A patent/CS203922B2/en unknown
- 1978-06-13 ES ES470743A patent/ES470743A1/en not_active Expired
- 1978-06-13 ES ES470746A patent/ES470746A1/en not_active Expired
- 1978-06-13 ES ES470745A patent/ES470745A1/en not_active Expired
- 1978-06-13 ES ES470744A patent/ES470744A1/en not_active Expired
- 1978-07-05 SU SU782631651A patent/SU1015826A3/en active
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1979
- 1979-02-01 PH PH22150A patent/PH13874A/en unknown
- 1979-02-01 PH PH22149A patent/PH14625A/en unknown
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1980
- 1980-03-06 AT AT0124380A patent/AT364356B/en not_active IP Right Cessation
- 1980-03-06 AT AT0124480A patent/AT363470B/en not_active IP Right Cessation
- 1980-10-24 CA CA363,273A patent/CA1110254A/en not_active Expired
- 1980-10-24 CA CA000363274A patent/CA1117541A/en not_active Expired
- 1980-10-30 CH CH808580A patent/CH625235A5/en not_active IP Right Cessation
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1981
- 1981-02-20 CH CH116181A patent/CH626358A5/en not_active IP Right Cessation
- 1981-02-20 CH CH116081A patent/CH626357A5/en not_active IP Right Cessation
- 1981-07-02 HK HK303/81A patent/HK30381A/en unknown
- 1981-07-02 HK HK305/81A patent/HK30581A/en unknown
- 1981-07-02 HK HK307/81A patent/HK30781A/en unknown
- 1981-07-02 HK HK304/81A patent/HK30481A/en unknown
- 1981-07-02 HK HK306/81A patent/HK30681A/en unknown
- 1981-12-09 NL NLAANVRAGE8105537,A patent/NL182476C/en not_active IP Right Cessation
- 1981-12-09 NL NLAANVRAGE8105538,A patent/NL182477C/en not_active IP Right Cessation
- 1981-12-09 NL NLAANVRAGE8105540,A patent/NL182805C/en not_active IP Right Cessation
- 1981-12-09 NL NLAANVRAGE8105539,A patent/NL182478C/en not_active IP Right Cessation
- 1981-12-30 MY MY287/81A patent/MY8100287A/en unknown
- 1981-12-30 MY MY267/81A patent/MY8100267A/en unknown
- 1981-12-30 MY MY262/81A patent/MY8100262A/en unknown
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1982
- 1982-01-29 SE SE8200519A patent/SE445042B/en not_active IP Right Cessation
- 1982-01-29 SE SE8200521A patent/SE452616B/en not_active IP Right Cessation
- 1982-01-29 SE SE8200520A patent/SE444564B/en not_active IP Right Cessation
- 1982-01-29 SE SE8200518A patent/SE445041B/en not_active IP Right Cessation
- 1982-01-29 SE SE8200522A patent/SE444565B/en not_active IP Right Cessation
- 1982-06-03 NO NO821849A patent/NO150559C/en unknown
- 1982-06-03 NO NO821851A patent/NO150560C/en unknown
- 1982-06-03 NO NO821848A patent/NO150043C/en unknown
- 1982-06-03 NO NO821850A patent/NO821850L/en unknown
- 1982-06-03 NO NO821847A patent/NO150042C/en unknown
- 1982-12-07 YU YU02703/82A patent/YU270382A/en unknown
- 1982-12-13 YU YU2747/82A patent/YU42613B/en unknown
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1983
- 1983-05-16 FI FI831702A patent/FI72720C/en not_active IP Right Cessation
- 1983-05-16 FI FI831700A patent/FI72119C/en not_active IP Right Cessation
- 1983-05-16 FI FI831703A patent/FI73424C/en not_active IP Right Cessation
- 1983-05-16 FI FI831704A patent/FI72721C/en not_active IP Right Cessation
- 1983-05-16 FI FI831701A patent/FI72723C/en not_active IP Right Cessation
- 1983-08-08 YU YU1663/83A patent/YU43190B/en unknown
- 1983-11-18 NO NO834236A patent/NO151365C/en unknown
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1986
- 1986-07-09 DK DK326186A patent/DK154079C/en active
- 1986-07-09 DK DK326086A patent/DK153401C/en not_active IP Right Cessation
- 1986-07-09 DK DK325986A patent/DK153484C/en active
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