CS261658B1 - Process for preparing 5-alkylthio-2-substituted-3-axo-2H-pyridazin-4-ol - Google Patents
Process for preparing 5-alkylthio-2-substituted-3-axo-2H-pyridazin-4-ol Download PDFInfo
- Publication number
- CS261658B1 CS261658B1 CS874373A CS437387A CS261658B1 CS 261658 B1 CS261658 B1 CS 261658B1 CS 874373 A CS874373 A CS 874373A CS 437387 A CS437387 A CS 437387A CS 261658 B1 CS261658 B1 CS 261658B1
- Authority
- CS
- Czechoslovakia
- Prior art keywords
- substituted
- oxo
- pyridazin
- chlorophenyl
- preparing
- Prior art date
Links
Landscapes
- Plural Heterocyclic Compounds (AREA)
Abstract
Riešenie sa týká sposobu přípravy 5-alkyltioi-2-substituovaných-3-oxo-2H-pyridazín- -4-olov všeobecného vzorca I, v ktorom R* 1 znamená alkyl s 1 až 6 atómami uhlíka, fenyl, cyklobexyl, benzyl, tolyl, chlórfenyl, 3-trifluórmetyl-4-chlórfenyl, R-! znamená alkyl s 1 až 3 atómami uhlíka, záhrevom příslušného 4-alkoxy-2-substituovaného- -3-oxo-2H-pyridazín-5-tiolu alebo jeho soli s alkalickým kovám pri teplote 60 až 140 °C v prostředí protónakceptorného rozpúšťadla zo skupiny zahřňujúcej metanol, etanol, propanol, dimetylsulfoxid, dimetylformamid, trietylamín, nitril kyseliny octovej a v případe použitia soli s alkalickým kovom i v prostředí vody, pričom pri reakcii nastane elektrofllný prešmyk katlónu R2. Riešenie je možné využit v chemickom priemysle.The solution relates to a method for preparing 5-alkylthiol-2-substituted-3-oxo-2H-pyridazin-4-ols of general formula I, in which R* 1 represents alkyl with 1 to 6 carbon atoms, phenyl, cyclohexyl, benzyl, tolyl, chlorophenyl, 3-trifluoromethyl-4-chlorophenyl, R-! means alkyl with 1 to 3 carbon atoms, heating the corresponding 4-alkoxy-2-substituted-3-oxo-2H-pyridazine-5-thiol or its alkali metal salt at a temperature of 60 to 140 °C in the environment of a proton acceptor solvent from the group including methanol, ethanol, propanol, dimethyl sulfoxide, dimethylformamide, triethylamine, acetic acid nitrile and in the case of using an alkali metal salt also in the environment of water, whereby the reaction results in an electrophilic rearrangement of the cation R2. The solution can be used in the chemical industry.
Description
Vynález sa týka spôsobu prípravy 5-alkyl-tio-2-substituovaných-3-oxo-2H-pyridazín-4--olov všeobecného vzorca I
v ktorom R1 znamená alkyl s 1 až 6 atómami uhlíka, fenyl, cyklohexyl, benzyl, tolyl, chlórfe-nyl, 3-trifluórmetyl-4-chlórfenyl a R2 znamená alkyl s 1 až 3 atómami uhlíka. Tieto zlúčeniny sú použiteľné ako medziprodukty k syntéze biologicky účinných látok.
Z literatúry je známy spôsob prípravy 5--alkyltio-2-substituovaných-3-oxo-2H-pyri-dazín-4-olov všeobecného vzorca I reakciou 5-alkylt»-4-halogén-2-substituovaného-3--oxo-2H-pyridazínu všeobecného vzorca III
v ktorom R1 a R2 majú už uvedený význam, X znamená halogén s hydroxidom sodným alebo draselným. [CS 175 205; Chem. zvesti 30; 663—673 (1976)].
Teraz sa zistil nový spôsob prípravy 5--alkyltio-2-substituovaných-3-oxo-2H-pyrida-zín-4-olov všeobecného vzorca I v ktorom
R1 a R2· majú už uvedený význam, reakciou 4-alkoxy-2-substituovaného-3-oxo-2H-pyrida-zín-5-tiolu alebo jeho soli s alkalickým kovom všeobecného vzorca II y ktorom
R1 a R2 majú už uvedený význam, M znamená vodík, sodík alebo draslík v prostredí protonoakceptorného organického rozpúšťadla zo skupiny zahrňujúcej metanol, etanol, propanol, dimetylsulfoxid, dimetylform-amid, trietylamín, nitril kyseliny octovej a ak M znamená sodík alebo draslík i v prostredí vody, pri teplote 60 až 140 °C, pričom pri reakcii nastane elektrofilný prešmyk katiónu R2.
Nasledujúce príklady ilustrujú, ale neobmedzujú predmet vynálezu.
Príklad 1
Príprava 2-metyl-5-metyltio -3-oxo-2H-py-ridazín-4-olu 1,5 g 4-metoxy-2-metyl-3~oxo-2II-pyľitla-zín-5-tiolu sa miešalo v 20 ml dimetylsulfo-xidu pri teplote 80 °C 4 hodiny. Dimetylsulfoxid sa oddestiloval za zníženého tlaku, zvyšok sa potom prekryštalizoval z toluénu (30 ml). Získalo sa 0,8 g bielej kryštalickej látky s teplotou topenia 156—158 °C. Analýza pre Ο6Η8Ν2Ο28 (m. h. = 172,2) vypočítané: 16,22 % N, 18,62 % S, 7ÍctpnfS· 16,01 % N, 19,11 % S. IČ v CHC1S: p (C=O) = 1615 cm“1, v (O—H) = 3 370 cm-1.
Príklad 2
Príprava 2-fenyl-5-metyltio-3-oxo-2H-pyrida-zín-4-olu 1,5 g 2-fenyl-4-metoxy-3-oxo-2H-pyridazín--5-tiolu sa miešalo v 20 ml trietylamínu 4 hodiny pri teplote 80 °C. Trietylamín sa oddestiloval za zníženého tlaku, zvyšok sa potom prekryštalizoval z etanolu (20 ml). Získalo sa 0,7 g bielej kryštalickej látky s t. t. 214—216 °C.
Analýza pre CnH10N2O2S (m. h. 234,26) vypočítané: 11,95 % N, .13,69 % S, zistené: 12,16 % N, 13,88 % S. IC v CHCLp v (G=O) 1 630 cm-1, p (OH) = 3 360 cm-1.
Príklad 3
Príprava 2-(3-chlórfenyl)-5-metyltio-3-oxo--2H-pyridazín-4-olu
The present invention relates to a process for the preparation of 5-alkylthio-2-substituted-3-oxo-2H-pyridazin-4-ol of formula I
wherein R 1 is alkyl of 1 to 6 carbon atoms, phenyl, cyclohexyl, benzyl, tolyl, chlorophenyl, 3-trifluoromethyl-4-chlorophenyl and R 2 is alkyl of 1 to 3 carbon atoms. These compounds are useful as intermediates in the synthesis of biologically active substances.
From the literature, a process for the preparation of 5-alkylthio-2-substituted-3-oxo-2H-pyridazin-4-ol of general formula I by reaction of 5-alkylthio-4-halo-2-substituted-3-oxo- 2H-pyridazine of formula III
wherein R 1 and R 2 are as defined above, X is halogen with sodium or potassium hydroxide. [CS 175 205; Chem. rumors 30; 663-673 (1976)].
A novel process has now been found for the preparation of 5-alkylthio-2-substituted-3-oxo-2H-pyridazin-4-ols of general formula I in which
R1 and R2 are as defined above by reacting a 4-alkoxy-2-substituted-3-oxo-2H-pyridazin-5-thiol or an alkali metal salt thereof of the formula (II) wherein
R 1 and R 2 are as defined above, M is hydrogen, sodium or potassium in an environment of a protonacceptor organic solvent such as methanol, ethanol, propanol, dimethylsulfoxide, dimethylformamide, triethylamine, acetic acid nitrile and when M is sodium or potassium in the environment water, at a temperature of 60 to 140 ° C, with electrophilic rearrangement of the cation R2 occurring in the reaction.
The following examples illustrate, but do not limit the invention.
Example 1
Preparation of 2-methyl-5-methylthio-3-oxo-2H-pyridazin-4-ol 1.5 g of 4-methoxy-2-methyl-3-oxo-2II-pyrithilane-5-thiol was stirred in 20 ml of dimethylsulfoxide at 80 ° C for 4 hours. The dimethyl sulfoxide was distilled off under reduced pressure, and then the residue was recrystallized from toluene (30 ml). 0.8 g of a white crystalline solid with a melting point of 156-158 ° C was obtained. Analysis for Ο6Η8Ν2Ο28 (mh = 172.2) calculated: 16.22% N, 18.62% S, 7ctctpnfS · 16.01% N, 19.11% S. IR in CHClS: p (C = O) = 1615 cm -1, v (O-H) = 3,370 cm -1.
Example 2
Preparation of 2-phenyl-5-methylthio-3-oxo-2H-pyridazin-4-ol 1.5 g of 2-phenyl-4-methoxy-3-oxo-2H-pyridazine-5-thiol were stirred at 20 ° C. ml of triethylamine at 80 ° C for 4 hours. Triethylamine was distilled off under reduced pressure, and then the residue was recrystallized from ethanol (20 ml). 0.7 g of a white crystalline solid was obtained, mp 214-216 ° C.
Analysis for C 11 H 10 N 2 O 2 S (m / z 234.26) calculated: 11.95% N, 13.69% S, found: 12.16% N, 13.88% S IC in CHCl 2 v (G = O) 1 630 cm -1, p (OH) = 3,360 cm -1.
Example 3
Preparation of 2- (3-chlorophenyl) -5-methylthio-3-oxo-2H-pyridazin-4-ol
Claims (1)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CS874373A CS261658B1 (en) | 1987-06-15 | 1987-06-15 | Process for preparing 5-alkylthio-2-substituted-3-axo-2H-pyridazin-4-ol |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CS874373A CS261658B1 (en) | 1987-06-15 | 1987-06-15 | Process for preparing 5-alkylthio-2-substituted-3-axo-2H-pyridazin-4-ol |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CS437387A1 CS437387A1 (en) | 1988-07-15 |
| CS261658B1 true CS261658B1 (en) | 1989-02-10 |
Family
ID=5386316
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CS874373A CS261658B1 (en) | 1987-06-15 | 1987-06-15 | Process for preparing 5-alkylthio-2-substituted-3-axo-2H-pyridazin-4-ol |
Country Status (1)
| Country | Link |
|---|---|
| CS (1) | CS261658B1 (en) |
-
1987
- 1987-06-15 CS CS874373A patent/CS261658B1/en unknown
Also Published As
| Publication number | Publication date |
|---|---|
| CS437387A1 (en) | 1988-07-15 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| ATE21245T1 (en) | PROCESSES FOR THE PRODUCTION OF INDOLE DERIVATIVES, THEIR USE AS VALUABLE INTERMEDIATE PRODUCTS AND NOVEL 4-HYDROXYINDOLES. | |
| RU2174978C2 (en) | Method of synthesis of pyrimidine derivative, intermediate compounds and method of their synthesis | |
| Senda et al. | Pyrimidine derivatives and related compounds. 15. Synthesis and analgetic and antiinflammatory activities of 1, 3-substituted 5-amino-6-methyluracil derivatives | |
| HU186539B (en) | Process for producing 1-bracket-1-cyclohexenyl-methyl-bracket closed-2-bracket-2-chloroethyl-bracket closed-pyrrolidine | |
| JPH0245442A (en) | Production of alpha, beta-unsaturated ketone | |
| KR860001073A (en) | Method for preparing imidazoline | |
| CS261658B1 (en) | Process for preparing 5-alkylthio-2-substituted-3-axo-2H-pyridazin-4-ol | |
| US3689498A (en) | Halide and sulfate salts of 5-amino-isoxazolylmethylene dialkylamine | |
| US4200759A (en) | Preparation of imidazo[2,1-a]isoindole compounds | |
| JPH02273677A (en) | Method for producing 2-phenylbenzotriazoles | |
| US4284562A (en) | Process for preparing pyrrole-2-acetic acids | |
| CA1122983A (en) | Method of producing 5-fluorouracil derivatives | |
| US4897495A (en) | Process for the preparation of pyrrolizine derivatives | |
| US3246010A (en) | 1, 5-diaryl-2-pyrrole propanols and ethers | |
| DE3260631D1 (en) | Process for the preparation of hydrazidines | |
| JP2708617B2 (en) | Method for producing 4,4-dialkyl-substituted thiazolidinethione | |
| Chen et al. | A facile synthesis of the 1, 3‐dithiolo [4, 5‐b] pyridine ring system via pyridylthiocyanates | |
| US4003907A (en) | Δ1 -1-Azacycloalkene-2-carboxylic acids and their production | |
| IL66237A (en) | Preparation of hydrazidines | |
| JP2000053651A (en) | Production of formylimidazoles | |
| IE53383B1 (en) | Chemical process | |
| FI881250A0 (en) | FOERFARANDE FOER FRAMSTAELLNING AV AMINOACYLANILINER. | |
| KR960022427A (en) | New preparation of 2- (4'substituted aryl) propionic acid | |
| JPS6043067B2 (en) | 2-Alkoxyindolizine derivatives and their production method | |
| HU209623B (en) | Process for producing uracyl derivatives |