US3310568A - Process for preparing esters of pyridine thiones - Google Patents
Process for preparing esters of pyridine thiones Download PDFInfo
- Publication number
- US3310568A US3310568A US343960A US34396064A US3310568A US 3310568 A US3310568 A US 3310568A US 343960 A US343960 A US 343960A US 34396064 A US34396064 A US 34396064A US 3310568 A US3310568 A US 3310568A
- Authority
- US
- United States
- Prior art keywords
- pyridinethione
- hydroxy
- anhydride
- sodium salt
- thiones
- 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
- 150000002148 esters Chemical class 0.000 title description 5
- WHMDPDGBKYUEMW-UHFFFAOYSA-N pyridine-2-thiol Chemical class SC1=CC=CC=N1 WHMDPDGBKYUEMW-UHFFFAOYSA-N 0.000 title description 3
- 238000004519 manufacturing process Methods 0.000 title 1
- 238000000034 method Methods 0.000 claims description 22
- 150000001875 compounds Chemical class 0.000 claims description 7
- 238000002360 preparation method Methods 0.000 claims description 5
- 230000003472 neutralizing effect Effects 0.000 claims description 3
- 239000002002 slurry Substances 0.000 claims description 3
- WFDIJRYMOXRFFG-UHFFFAOYSA-N Acetic anhydride Chemical compound CC(=O)OC(C)=O WFDIJRYMOXRFFG-UHFFFAOYSA-N 0.000 description 17
- 239000000047 product Substances 0.000 description 13
- 150000008064 anhydrides Chemical class 0.000 description 11
- 159000000000 sodium salts Chemical class 0.000 description 11
- -1 1-hydroxy-2-pyridinethione compound Chemical class 0.000 description 10
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 9
- 235000014113 dietary fatty acids Nutrition 0.000 description 9
- 229930195729 fatty acid Natural products 0.000 description 9
- 239000000194 fatty acid Substances 0.000 description 9
- 150000004665 fatty acids Chemical class 0.000 description 8
- 239000000243 solution Substances 0.000 description 8
- 125000004432 carbon atom Chemical group C* 0.000 description 4
- 239000000203 mixture Substances 0.000 description 4
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 4
- QTBSBXVTEAMEQO-UHFFFAOYSA-M Acetate Chemical compound CC([O-])=O QTBSBXVTEAMEQO-UHFFFAOYSA-M 0.000 description 3
- 229910052739 hydrogen Inorganic materials 0.000 description 3
- 239000001257 hydrogen Substances 0.000 description 3
- 239000003973 paint Substances 0.000 description 3
- 239000002689 soil Substances 0.000 description 3
- WKBOTKDWSSQWDR-UHFFFAOYSA-N Bromine atom Chemical compound [Br] WKBOTKDWSSQWDR-UHFFFAOYSA-N 0.000 description 2
- ZAMOUSCENKQFHK-UHFFFAOYSA-N Chlorine atom Chemical compound [Cl] ZAMOUSCENKQFHK-UHFFFAOYSA-N 0.000 description 2
- 125000003545 alkoxy group Chemical group 0.000 description 2
- 125000000217 alkyl group Chemical group 0.000 description 2
- 239000007864 aqueous solution Substances 0.000 description 2
- GDTBXPJZTBHREO-UHFFFAOYSA-N bromine Substances BrBr GDTBXPJZTBHREO-UHFFFAOYSA-N 0.000 description 2
- 229910052794 bromium Inorganic materials 0.000 description 2
- 229910052801 chlorine Inorganic materials 0.000 description 2
- 239000000460 chlorine Substances 0.000 description 2
- 238000001914 filtration Methods 0.000 description 2
- 239000000417 fungicide Substances 0.000 description 2
- 229910052736 halogen Inorganic materials 0.000 description 2
- 150000002367 halogens Chemical class 0.000 description 2
- 150000002431 hydrogen Chemical group 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 238000002844 melting Methods 0.000 description 2
- 230000008018 melting Effects 0.000 description 2
- YBBJKCMMCRQZMA-UHFFFAOYSA-N pyrithione Chemical class ON1C=CC=CC1=S YBBJKCMMCRQZMA-UHFFFAOYSA-N 0.000 description 2
- SMZOUWXMTYCWNB-UHFFFAOYSA-N 2-(2-methoxy-5-methylphenyl)ethanamine Chemical compound COC1=CC=C(C)C=C1CCN SMZOUWXMTYCWNB-UHFFFAOYSA-N 0.000 description 1
- ZCYVEMRRCGMTRW-UHFFFAOYSA-N 7553-56-2 Chemical compound [I] ZCYVEMRRCGMTRW-UHFFFAOYSA-N 0.000 description 1
- FERIUCNNQQJTOY-UHFFFAOYSA-N Butyric acid Chemical compound CCCC(O)=O FERIUCNNQQJTOY-UHFFFAOYSA-N 0.000 description 1
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- 241000233866 Fungi Species 0.000 description 1
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 1
- ZLMJMSJWJFRBEC-UHFFFAOYSA-N Potassium Chemical compound [K] ZLMJMSJWJFRBEC-UHFFFAOYSA-N 0.000 description 1
- 101150089644 Rnls gene Proteins 0.000 description 1
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 description 1
- NIXOWILDQLNWCW-UHFFFAOYSA-N acrylic acid group Chemical group C(C=C)(=O)O NIXOWILDQLNWCW-UHFFFAOYSA-N 0.000 description 1
- 230000000844 anti-bacterial effect Effects 0.000 description 1
- 229940053200 antiepileptics fatty acid derivative Drugs 0.000 description 1
- 239000003899 bactericide agent Substances 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 239000006227 byproduct Substances 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 238000005119 centrifugation Methods 0.000 description 1
- LDHQCZJRKDOVOX-NSCUHMNNSA-N crotonic acid Chemical compound C\C=C\C(O)=O LDHQCZJRKDOVOX-NSCUHMNNSA-N 0.000 description 1
- 238000010908 decantation Methods 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 239000003085 diluting agent Substances 0.000 description 1
- BEFDCLMNVWHSGT-UHFFFAOYSA-N ethenylcyclopentane Chemical compound C=CC1CCCC1 BEFDCLMNVWHSGT-UHFFFAOYSA-N 0.000 description 1
- 230000001747 exhibiting effect Effects 0.000 description 1
- 239000004744 fabric Substances 0.000 description 1
- 238000002329 infrared spectrum Methods 0.000 description 1
- PNDPGZBMCMUPRI-UHFFFAOYSA-N iodine Chemical compound II PNDPGZBMCMUPRI-UHFFFAOYSA-N 0.000 description 1
- 229910052740 iodine Inorganic materials 0.000 description 1
- 239000011630 iodine Substances 0.000 description 1
- KQNPFQTWMSNSAP-UHFFFAOYSA-N isobutyric acid Chemical compound CC(C)C(O)=O KQNPFQTWMSNSAP-UHFFFAOYSA-N 0.000 description 1
- 239000010985 leather Substances 0.000 description 1
- 229910003002 lithium salt Inorganic materials 0.000 description 1
- 159000000002 lithium salts Chemical class 0.000 description 1
- 239000000123 paper Substances 0.000 description 1
- 239000011591 potassium Substances 0.000 description 1
- 229910052700 potassium Inorganic materials 0.000 description 1
- 239000002244 precipitate Substances 0.000 description 1
- 239000003755 preservative agent Substances 0.000 description 1
- 239000000376 reactant Substances 0.000 description 1
- 239000012429 reaction media Substances 0.000 description 1
- 239000011541 reaction mixture Substances 0.000 description 1
- 230000035484 reaction time Effects 0.000 description 1
- 238000011084 recovery Methods 0.000 description 1
- 238000001953 recrystallisation Methods 0.000 description 1
- 239000004334 sorbic acid Substances 0.000 description 1
- 229940075582 sorbic acid Drugs 0.000 description 1
- 235000010199 sorbic acid Nutrition 0.000 description 1
- WSWCOQWTEOXDQX-MQQKCMAXSA-N sorbic acid group Chemical group C(\C=C\C=C\C)(=O)O WSWCOQWTEOXDQX-MQQKCMAXSA-N 0.000 description 1
- 238000005507 spraying Methods 0.000 description 1
- 239000007858 starting material Substances 0.000 description 1
- 229910052717 sulfur Inorganic materials 0.000 description 1
- 239000011593 sulfur Substances 0.000 description 1
- 239000002966 varnish Substances 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D213/00—Heterocyclic compounds containing six-membered rings, not condensed with other rings, with one nitrogen atom as the only ring hetero atom and three or more double bonds between ring members or between ring members and non-ring members
- C07D213/02—Heterocyclic compounds containing six-membered rings, not condensed with other rings, with one nitrogen atom as the only ring hetero atom and three or more double bonds between ring members or between ring members and non-ring members having three double bonds between ring members or between ring members and non-ring members
- C07D213/89—Heterocyclic compounds containing six-membered rings, not condensed with other rings, with one nitrogen atom as the only ring hetero atom and three or more double bonds between ring members or between ring members and non-ring members having three double bonds between ring members or between ring members and non-ring members with hetero atoms directly attached to the ring nitrogen atom
Definitions
- This invention relates to a process for the preparation of esters of pyridinethione derivatives. More particularly, this invention relates to a method in which the sodium salt of a 1-hydroxy-2-pyridinethione compound is reacted with a fatty acid anhydride to form in high yields the corresponding fatty acid ester.
- the yield of the esters formed by the novel method of this invention is from 80 to 90 percent or more as compared to about 35 percent for methods known in the art for preparing these same compounds.
- advantage of this process is that it is carried out at tem peratures ranging from about 5 C. to about +30 C. thus avoiding the formation of undesirable side products which takes place at the temperatures utilized in the prior art processes, i.e. 80 90 C.
- a purer product is obtained with the method of this invention than with prior art methods since the reaction emperature is substantially decreased.
- the purity of the products of this invention is shown by the sharp melting points as well as by the infrared spectra exhibited by these materials.
- the sodium salt of a 1-hydroxy-2-pyridinethione compound by reacting sodium hydroxide with the pyridinethione compound and then in a second step reacting sodium salt with a fatty acid anhydride under aqueous conditions.
- the potassium and lithium salts of the pyridinethione starting materials are also useful.
- R is hydrogen, alkyl of not more than 5 carbon atoms, alkoxy of not more than 5 carbon atoms or a halogen selected from the group consisting of chlorine, bromine and iodine and n is a positive interger of no greater than four and preferably one.
- Useful 1-hydroxy-2-pyridinethione compounds include, for example, l-hydroxy-2-pyridinethione, 1-hydroxy-3- methoxy-2-pyridinethione, 1-hydroxy-5-butoxy-2-pyridinethione, l-hydroxy-3-methyl-2-pyridinethione, l-hydroxy- 4,6-di-n-butyls2-pyridinethione, 1-hydroxy-3,4-dichloro-2- pyridinethione, 1-hydroxy-5-bromo-2-pyridinethione.
- Suitable fatty acids whose anhydrides are utilizable as startingv materials in the process of this invention include: acetic, n-propionic, isopropionic, n-butyric, isobutyric, acrylic, crotonic and sorbic. Any fatty acid anhydride yielding a water-soluble fatty acid is suitable for the process of this invention.
- the stoichiometric quantity of fatty acid anhydride can be employed in this invention, preferably from about 3 to about 10 moles of acetic anhydride are employed per mole of the sodium salt of the l-hydroxy-2- pyridinethione compound charged to the reactor.
- the temperature will range from about 5 C. to about +30 C. and preferably will be from about 0 C. to about 15 C. If less than about 3 moles of anhydride per mole of the pyridinethione compound are untilized,
- the preferred pressure is atmospheric although pressures ranging from subatmospheric up to 10 atmospheres or more can be used.
- the reaction time will vary from about 0.1 to 3 hours or more depending upon the particular reactants and reaction conditions utilized. 1
- Recovery of the products of this invention, which are insoluble in the reaction medium employed, can be accomplished by filtration, centrifugation, decantation, etc.
- a solution of the sodium salt of l-hydroxy-Z-pyridinethione was prepared by neutralizing an aqueous slurry of 1-hydroxy-2-pyridinethione with 25 percent aqueous sodium hydroxide until the pH of the resulting solution was in the range of 6.5 to 7.0, the sodium salt concentration was 12.5 weight percent.
- the product was submitted for infrared analysis and was shown to be pure 1-hydroxy-2-pyridinethione acetate.
- the esters of this invention are active bactericides and fungicides.
- the fatty acid derivatives of this invention can, therefore, be used as preservatives (for example, in leather, paper and fabrics) and especially in paints and varnish to render them resistant against mildew or other fungus attack.
- the mixed anhydrides are simply mixed with the paint.
- the mixed anhydrides of this invention find further use as agricultural fungicides, the mixed anhydride being added either directly to the soil (by sprinkling the mixed anhydride itself or a composition of the mixed anhydride and suitable diluents onto the surface of the soil and then thoroughly intermixing the soil and mixed anhydride) or directly to plant foliage by spraying a composition thereof with a suitable carrier.
- a process for the preparation of an ester which comprises (A) neutralizing an aqueous slurry of a compound of the formula:
- R is selected from the group consisting of hydrogen, alkyl of not more than 5 carbon atoms, alkoxy of not more than 5 carbon atoms, and a halogen selected from the group consisting of chlorine, bromine and iodine,
- n is an integer no higher than four, with sodium hydroxide until the pH of the resulting solution is in the range of about 6.5 to 7 whereby the sodium salt of the said compound is formed and (B) reacting the said sodium salt in aqueous solution with fro-m about3 to about 10 moles of an anhyd-ride of a fatty acid selected from the group consisting of acetic, n-propionic, isopropionic, n-butyric, isobutyric, acrylic, crotonic and sorbic acid.
- the temperature of the reaction is from about 5 C. to about +30 C.
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Description
United States Patent This invention relates to a process for the preparation of esters of pyridinethione derivatives. More particularly, this invention relates to a method in which the sodium salt of a 1-hydroxy-2-pyridinethione compound is reacted with a fatty acid anhydride to form in high yields the corresponding fatty acid ester.
The yield of the esters formed by the novel method of this invention is from 80 to 90 percent or more as compared to about 35 percent for methods known in the art for preparing these same compounds. advantage of this process is that it is carried out at tem peratures ranging from about 5 C. to about +30 C. thus avoiding the formation of undesirable side products which takes place at the temperatures utilized in the prior art processes, i.e. 80 90 C. Thus a purer product is obtained with the method of this invention than with prior art methods since the reaction emperature is substantially decreased. The purity of the products of this invention is shown by the sharp melting points as well as by the infrared spectra exhibited by these materials.
Therefore, the products produced by the process of this invention require no recrystallization, while the same products, prepared by known methods, must be recrystallized for comparable purity.
In the process of this invention there is first prepared the sodium salt of a 1-hydroxy-2-pyridinethione compound by reacting sodium hydroxide with the pyridinethione compound and then in a second step reacting sodium salt with a fatty acid anhydride under aqueous conditions. The potassium and lithium salts of the pyridinethione starting materials are also useful.
The two-stage process of the present invention proceeds according to the equations'below where, for purposes of illustration, acetic acid anhydride is shown as the fatty acid anhydride:
Another 3,310,568 Patented Mar. 21, 1967 ice may be in tautomeric equilibrium With the compound:
wherein R is hydrogen, alkyl of not more than 5 carbon atoms, alkoxy of not more than 5 carbon atoms or a halogen selected from the group consisting of chlorine, bromine and iodine and n is a positive interger of no greater than four and preferably one.
Useful 1-hydroxy-2-pyridinethione compounds include, for example, l-hydroxy-2-pyridinethione, 1-hydroxy-3- methoxy-2-pyridinethione, 1-hydroxy-5-butoxy-2-pyridinethione, l-hydroxy-3-methyl-2-pyridinethione, l-hydroxy- 4,6-di-n-butyls2-pyridinethione, 1-hydroxy-3,4-dichloro-2- pyridinethione, 1-hydroxy-5-bromo-2-pyridinethione.
Suitable fatty acids whose anhydrides are utilizable as startingv materials in the process of this invention include: acetic, n-propionic, isopropionic, n-butyric, isobutyric, acrylic, crotonic and sorbic. Any fatty acid anhydride yielding a water-soluble fatty acid is suitable for the process of this invention.
Although the stoichiometric quantity of fatty acid anhydride can be employed in this invention, preferably from about 3 to about 10 moles of acetic anhydride are employed per mole of the sodium salt of the l-hydroxy-2- pyridinethione compound charged to the reactor. Generally, the temperature will range from about 5 C. to about +30 C. and preferably will be from about 0 C. to about 15 C. If less than about 3 moles of anhydride per mole of the pyridinethione compound are untilized,
it has been found that a lower yield of a product exhibiting a lower melting point than the preferred product is obtained. In the process of this invention the preferred pressure is atmospheric although pressures ranging from subatmospheric up to 10 atmospheres or more can be used. The reaction time will vary from about 0.1 to 3 hours or more depending upon the particular reactants and reaction conditions utilized. 1
Recovery of the products of this invention, which are insoluble in the reaction medium employed, can be accomplished by filtration, centrifugation, decantation, etc.
The following examples which illustrate the process of this invention are to be considered not limitative.
EXAMPLE I (A) Preparation of the sodium salt of l-hydroxy-Z- pyridinethione:
A solution of the sodium salt of l-hydroxy-Z-pyridinethione was prepared by neutralizing an aqueous slurry of 1-hydroxy-2-pyridinethione with 25 percent aqueous sodium hydroxide until the pH of the resulting solution was in the range of 6.5 to 7.0, the sodium salt concentration was 12.5 weight percent.
(B) Preparation of the acetate of l-hydroxy-Z-pyridinethione:
Five hundred grams of this solution (63 g. of the sodium salt .of l-hydroxy-2-pyridinethione, 0.422 mole) was diluted with 500 grams of water and the solution then cooled to 0-5" C. To the cold solution, g. acetic anhydride (1.23 moles) were added and the mixture stirred at 0 to 5 C. for 0.5 hour. The yellow product precipitate was then filtered out, washed several times with cold water, and dried for 16 hours in a vacuum oven at 50 C. The dried product (the acetate of l-hydroxy- Z-pyridinethione) weighed 64.3 grams (0.380 mole); M.P. 8888.5 C. Yield was 90.2 percent of the theoretical quantity.
The product was analyzed for carbon, hydrogen and sulfur and the following results were obtained:
Analysis.Calcd for C H O NS: C, 49.70; H, 4.14; S, 19.95. Found: C, 49.59; H, 4.43; S, 19.10.
EXAMPLE II Two hundred grams of an aqueous solution of the sodium salt of l-hydroXy-2-pyridin-ethione (0.097 mole) was diluted with 400 grams of water and the solution cooled to C. To the cold solution 35 rnls. (0.343 mole) of acetic anhydride was added and the mixture stirred at 0 to C. for 0.5 hour. The yellow product, which had precipitated from the reaction mixture, was then recovered by filtration, washed several times with cold water and dried for 16 hours in a vacuum oven at about 50 C. The dried product (the acetate of l-hydroxy-Z-pyridinethione) weighed 0.075 mole which corresponds to a yield of 77.8 percent.
The product was submitted for infrared analysis and was shown to be pure 1-hydroxy-2-pyridinethione acetate.
The esters of this invention are active bactericides and fungicides. The fatty acid derivatives of this invention can, therefore, be used as preservatives (for example, in leather, paper and fabrics) and especially in paints and varnish to render them resistant against mildew or other fungus attack. In the protection of paints, for example, the mixed anhydrides are simply mixed with the paint.
The mixed anhydrides of this invention find further use as agricultural fungicides, the mixed anhydride being added either directly to the soil (by sprinkling the mixed anhydride itself or a composition of the mixed anhydride and suitable diluents onto the surface of the soil and then thoroughly intermixing the soil and mixed anhydride) or directly to plant foliage by spraying a composition thereof with a suitable carrier.
What is claimed is:
1. A process for the preparation of an ester which comprises (A) neutralizing an aqueous slurry of a compound of the formula:
wherein R is selected from the group consisting of hydrogen, alkyl of not more than 5 carbon atoms, alkoxy of not more than 5 carbon atoms, and a halogen selected from the group consisting of chlorine, bromine and iodine,, and n is an integer no higher than four, with sodium hydroxide until the pH of the resulting solution is in the range of about 6.5 to 7 whereby the sodium salt of the said compound is formed and (B) reacting the said sodium salt in aqueous solution with fro-m about3 to about 10 moles of an anhyd-ride of a fatty acid selected from the group consisting of acetic, n-propionic, isopropionic, n-butyric, isobutyric, acrylic, crotonic and sorbic acid.
2. The process of claim 1 wherein the temperature of the reaction is from about 5 C. to about +30 C.
3. The process of claim 1 wherein the said anhydride is acetic anhydride.
4. The process of claim 1 wherein the said compound is: Y
I OH
5. The process of claim 1 wherein the said anhydride is acetic anhydride, the said compound is:
and the temperature of the reaction is from about 5 C. to about +30 C.
References Cited by the Examiner UNITED STATES PATENTS 2,758,116 8/1956 Wiseogle et a1. -260.294.8
WALTER A. MODANCE, Primary Examiner.
ALAN L. ROTMAN, Assistant Examiner.
Claims (1)
1. A PROCESS FOR THE PREPARATION OF AN ESTER WHICH COMPRISES (A) NEUTRALIZING AN AQUEOUS SLURRY OF A COMPOUND OF THE FORMULA:
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US343960A US3310568A (en) | 1964-02-11 | 1964-02-11 | Process for preparing esters of pyridine thiones |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US343960A US3310568A (en) | 1964-02-11 | 1964-02-11 | Process for preparing esters of pyridine thiones |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US3310568A true US3310568A (en) | 1967-03-21 |
Family
ID=23348411
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US343960A Expired - Lifetime US3310568A (en) | 1964-02-11 | 1964-02-11 | Process for preparing esters of pyridine thiones |
Country Status (1)
| Country | Link |
|---|---|
| US (1) | US3310568A (en) |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2758116A (en) * | 1956-03-08 | 1956-08-07 | Olin Mathieson | Pyridine derivatives |
-
1964
- 1964-02-11 US US343960A patent/US3310568A/en not_active Expired - Lifetime
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2758116A (en) * | 1956-03-08 | 1956-08-07 | Olin Mathieson | Pyridine derivatives |
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