CN111763183A - Preparation method of 1-phenyl-3- (1,2, 3-thiadiazole-5-yl) urea - Google Patents
Preparation method of 1-phenyl-3- (1,2, 3-thiadiazole-5-yl) urea Download PDFInfo
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- CN111763183A CN111763183A CN202010614804.6A CN202010614804A CN111763183A CN 111763183 A CN111763183 A CN 111763183A CN 202010614804 A CN202010614804 A CN 202010614804A CN 111763183 A CN111763183 A CN 111763183A
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- phenyl
- thiadiazole
- urea
- reaction
- thiadiazol
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- HFCYZXMHUIHAQI-UHFFFAOYSA-N Thidiazuron Chemical compound C=1C=CC=CC=1NC(=O)NC1=CN=NS1 HFCYZXMHUIHAQI-UHFFFAOYSA-N 0.000 title claims abstract description 37
- 238000002360 preparation method Methods 0.000 title abstract description 18
- 238000006243 chemical reaction Methods 0.000 claims abstract description 23
- DGTNSSLYPYDJGL-UHFFFAOYSA-N phenyl isocyanate Chemical compound O=C=NC1=CC=CC=C1 DGTNSSLYPYDJGL-UHFFFAOYSA-N 0.000 claims abstract description 18
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 16
- 239000002994 raw material Substances 0.000 claims abstract description 13
- 239000007787 solid Substances 0.000 claims abstract description 11
- PVGHNTXQMCYYGF-UHFFFAOYSA-N thiadiazol-5-amine Chemical compound NC1=CN=NS1 PVGHNTXQMCYYGF-UHFFFAOYSA-N 0.000 claims abstract description 10
- 238000001035 drying Methods 0.000 claims abstract description 7
- 238000004519 manufacturing process Methods 0.000 claims abstract description 7
- 238000000967 suction filtration Methods 0.000 claims abstract description 7
- 238000005406 washing Methods 0.000 claims abstract description 7
- YXFVVABEGXRONW-UHFFFAOYSA-N Toluene Chemical compound CC1=CC=CC=C1 YXFVVABEGXRONW-UHFFFAOYSA-N 0.000 claims description 36
- 238000003756 stirring Methods 0.000 claims description 16
- 238000001816 cooling Methods 0.000 claims description 15
- 238000000034 method Methods 0.000 claims description 15
- ZMANZCXQSJIPKH-UHFFFAOYSA-N Triethylamine Chemical group CCN(CC)CC ZMANZCXQSJIPKH-UHFFFAOYSA-N 0.000 claims description 9
- FXHOOIRPVKKKFG-UHFFFAOYSA-N N,N-Dimethylacetamide Chemical compound CN(C)C(C)=O FXHOOIRPVKKKFG-UHFFFAOYSA-N 0.000 claims description 7
- 239000003054 catalyst Substances 0.000 claims description 7
- 239000003960 organic solvent Substances 0.000 claims description 7
- BAVYZALUXZFZLV-UHFFFAOYSA-N Methylamine Chemical compound NC BAVYZALUXZFZLV-UHFFFAOYSA-N 0.000 claims description 6
- 238000010438 heat treatment Methods 0.000 claims description 6
- 238000004128 high performance liquid chromatography Methods 0.000 claims description 4
- HQABUPZFAYXKJW-UHFFFAOYSA-N butan-1-amine Chemical compound CCCCN HQABUPZFAYXKJW-UHFFFAOYSA-N 0.000 claims description 3
- CUWHXIJMTMMRTI-UHFFFAOYSA-N thiadiazol-4-amine Chemical compound NC1=CSN=N1 CUWHXIJMTMMRTI-UHFFFAOYSA-N 0.000 claims description 3
- 239000000203 mixture Substances 0.000 claims description 2
- 239000007858 starting material Substances 0.000 claims 1
- 239000002904 solvent Substances 0.000 abstract description 16
- 238000011084 recovery Methods 0.000 abstract description 8
- 239000002131 composite material Substances 0.000 abstract description 4
- 230000009286 beneficial effect Effects 0.000 abstract description 2
- 238000009835 boiling Methods 0.000 abstract description 2
- WEVYAHXRMPXWCK-UHFFFAOYSA-N Acetonitrile Chemical compound CC#N WEVYAHXRMPXWCK-UHFFFAOYSA-N 0.000 description 12
- WYURNTSHIVDZCO-UHFFFAOYSA-N Tetrahydrofuran Chemical compound C1CCOC1 WYURNTSHIVDZCO-UHFFFAOYSA-N 0.000 description 4
- DLYUQMMRRRQYAE-UHFFFAOYSA-N tetraphosphorus decaoxide Chemical compound O1P(O2)(=O)OP3(=O)OP1(=O)OP2(=O)O3 DLYUQMMRRRQYAE-UHFFFAOYSA-N 0.000 description 4
- 238000002844 melting Methods 0.000 description 3
- 230000008018 melting Effects 0.000 description 3
- 239000012452 mother liquor Substances 0.000 description 3
- 229920000742 Cotton Polymers 0.000 description 2
- 241000196324 Embryophyta Species 0.000 description 2
- 241000219146 Gossypium Species 0.000 description 2
- 239000000498 cooling water Substances 0.000 description 2
- 238000001514 detection method Methods 0.000 description 2
- 239000003630 growth substance Substances 0.000 description 2
- 238000006467 substitution reaction Methods 0.000 description 2
- YLQBMQCUIZJEEH-UHFFFAOYSA-N tetrahydrofuran Natural products C=1C=COC=1 YLQBMQCUIZJEEH-UHFFFAOYSA-N 0.000 description 2
- KLSJWNVTNUYHDU-UHFFFAOYSA-N Amitrole Chemical compound NC1=NC=NN1 KLSJWNVTNUYHDU-UHFFFAOYSA-N 0.000 description 1
- 208000005156 Dehydration Diseases 0.000 description 1
- 241000219094 Vitaceae Species 0.000 description 1
- 230000032823 cell division Effects 0.000 description 1
- 238000003889 chemical engineering Methods 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 238000006482 condensation reaction Methods 0.000 description 1
- 230000018044 dehydration Effects 0.000 description 1
- 238000006297 dehydration reaction Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000012847 fine chemical Substances 0.000 description 1
- 235000021021 grapes Nutrition 0.000 description 1
- 238000003306 harvesting Methods 0.000 description 1
- 231100000053 low toxicity Toxicity 0.000 description 1
- 150000002978 peroxides Chemical class 0.000 description 1
- 230000001737 promoting effect Effects 0.000 description 1
- 238000001308 synthesis method Methods 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D285/00—Heterocyclic compounds containing rings having nitrogen and sulfur atoms as the only ring hetero atoms, not provided for by groups C07D275/00 - C07D283/00
- C07D285/01—Five-membered rings
- C07D285/02—Thiadiazoles; Hydrogenated thiadiazoles
- C07D285/04—Thiadiazoles; Hydrogenated thiadiazoles not condensed with other rings
- C07D285/06—1,2,3-Thiadiazoles; Hydrogenated 1,2,3-thiadiazoles
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Nitrogen- Or Sulfur-Containing Heterocyclic Ring Compounds With Rings Of Six Or More Members (AREA)
- Plural Heterocyclic Compounds (AREA)
- Low-Molecular Organic Synthesis Reactions Using Catalysts (AREA)
Abstract
The invention relates to a preparation method of 1-phenyl-3- (1,2, 3-thiadiazole-5-yl) urea, which comprises the steps of taking 5-amino-1.2.3-thiadiazole as a raw material, adding a composite solvent, reacting with phenyl isocyanate, and then sequentially carrying out suction filtration, washing and drying to obtain a light yellow solid, namely the 1-phenyl-3- (1,2, 3-thiadiazole-5-yl) urea. The invention has the beneficial effects that: the preparation method has mild and controllable reaction conditions, high yield and excellent quality of the obtained product; the solvent has higher boiling point, is not easy to dissolve in water, is convenient to recover, has less loss, reduces equipment investment, shortens production period, has the recovery utilization rate of the solvent of more than 95 percent, and has higher product yield.
Description
Technical Field
The invention belongs to the technical field of fine chemical engineering, relates to a synthesis method of a growth regulator intermediate, and particularly relates to a preparation method of 1-phenyl-3- (1,2, 3-thiadiazole-5-yl) urea.
Background
1-phenyl-3- (1,2, 3-thiadiazole-5-yl) urea is an important growth regulator intermediate, has strong activity of promoting plant cell division, and is widely applied to economic plants such as cotton, grapes and the like. Has the characteristics of broad spectrum, high efficiency, low toxicity and low residue, is environment-friendly, and is commonly used as a defoliating agent before cotton harvesting abroad. The product is developed by developed countries in Europe and America and the like, and has the advantages of long and complicated production process route, harsh process conditions, high technical requirements and high production difficulty. The 1-phenyl-3- (1,2, 3-thiadiazol-5-yl) urea is generally prepared by condensation reaction of 5 amino-1, 2, 3-thiadiazoles with phenyl isocyanate at 30-35 ℃ in the presence of acetonitrile. The reaction selectivity is poor, the yield is low, the product content is low and is generally about 95%, the water content of a post-treatment solvent is high, the reuse is difficult, and dehydration treatment is needed.
In view of this, this patent is filed.
Disclosure of Invention
In order to solve the problems in the prior art, the invention provides a preparation method of 1-phenyl-3- (1,2, 3-thiadiazole-5-yl) urea, which adopts a composite solvent for preparation, and has the advantages of mild reaction conditions, easy operation, high yield and convenient solvent recovery and treatment.
The invention aims to provide a preparation method of 1-phenyl-3- (1,2, 3-thiadiazole-5-yl) urea.
A method of preparing 1-phenyl-3- (1,2, 3-thiadiazol-5-yl) urea according to an embodiment of the present invention, said method comprising the steps of:
taking 5-amino-1, 2, 3-thiadiazole as a raw material, adding an anhydrous organic solvent, dropwise adding phenyl isocyanate while stirring, cooling and reacting, immediately adding a catalyst after dropwise adding, then adding N, N-dimethylacetamide, heating to 35-37 ℃ while stirring, preserving heat, reacting until the raw material disappears, stopping the reaction, cooling to below 15 ℃, and sequentially performing suction filtration, water washing and drying to obtain a light yellow solid, namely 1-phenyl-3- (1,2, 3-thiadiazole-5-yl) urea; the reaction equation is as follows:
a method for preparing 1-phenyl-3- (1,2, 3-thiadiazol-5-yl) urea according to an embodiment of the present invention, wherein the anhydrous organic solvent is anhydrous toluene. The anhydrous organic solvent may also be acetonitrile or tetrahydrofuran, preferably anhydrous toluene.
According to the preparation method of 1-phenyl-3- (1,2, 3-thiadiazole-5-yl) urea of the embodiment of the present invention, further, the anhydrous toluene is added in an amount of 1mol of the 5 amino-1.2.3-thiadiazole to 400-600ml of anhydrous toluene. Preferably, 500ml of anhydrous toluene is added.
The preparation method of the 1-phenyl-3- (1,2, 3-thiadiazole-5-yl) urea according to the embodiment of the invention is characterized in that the molar ratio of the 5-amino-1.2.3-thiadiazole to the phenyl isocyanate is 1 (1-1.2).
The preparation method of the 1-phenyl-3- (1,2, 3-thiadiazole-5-yl) urea according to the embodiment of the invention is characterized in that the molar ratio of the 5-amino-1.2.3-thiadiazole to the phenyl isocyanate is 1: 1.01. A method of preparing 1-phenyl-3- (1,2, 3-thiadiazol-5-yl) urea according to an embodiment of the present invention, wherein said phenyl isocyanate is added dropwise within 1 hour.
According to the preparation method of the 1-phenyl-3- (1,2, 3-thiadiazole-5-yl) urea of the embodiment of the invention, phenyl isocyanate is dropwise added with stirring, the temperature is reduced, the reaction is carried out, and the reaction temperature is kept to be 30-38 ℃ until the dropwise addition is finished.
According to the preparation method of the 1-phenyl-3- (1,2, 3-thiadiazole-5-yl) urea, the temperature is further reduced by cooling cold water into the jacket layer of the reactor.
According to the preparation method of the 1-phenyl-3- (1,2, 3-thiadiazole-5-yl) urea, NN-dimethylacetamide is added, the mixture is heated to 35-37 ℃ while stirring, the temperature is kept for 3.5-4.5 hours, and the reaction is completed.
According to the preparation method of 1-phenyl-3- (1,2, 3-thiadiazole-5-yl) urea of the embodiment of the present invention, HPLC is used to detect whether the reaction of the raw materials is complete.
The preparation method of 1-phenyl-3- (1,2, 3-thiadiazole-5-yl) urea according to the embodiment of the present invention, wherein the catalyst is triethylamine or monomethylamine or n-butylamine.
The invention has the beneficial effects that: the invention provides a preparation method of 1-phenyl-3- (1,2, 3-thiadiazole-5-yl) urea, which is characterized in that solid 5-amino-1.2.3-thiadiazole and phenyl isocyanate are used for obtaining better reaction conditions at a specific temperature by using a composite solvent (comprising an anhydrous organic solvent and a small amount of N.N-dimethylacetamide) and adopting a specific part feeding sequence, the reaction is mild and controllable, the yield is high, and the obtained product has excellent quality.
In the prior art, most of the hydrophilic solvents are adopted, the recovery rate is not high, the recovery rate is generally 90 percent, phosphorus pentoxide is required to absorb water, and the product yield is low; the invention adopts the composite solvent, the boiling point of the solvent is higher, the solvent is not easy to dissolve in water, the recovery is convenient, the loss is less, the equipment investment is reduced, the production period is shortened, the recovery utilization rate of the solvent is more than 95 percent, and the product yield is higher.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the technical solutions of the present invention will be described in detail below. It is to be understood that the embodiments described are only some embodiments of the invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the examples given herein without any inventive step, are within the scope of the present invention.
In some more specific embodiments, the preparation method comprises the following steps:
taking 5-amino-1, 2, 3-thiadiazole as a raw material, adding an anhydrous organic solvent, dropwise adding phenyl isocyanate while stirring, cooling and reacting, adding a catalyst after dropwise adding, then adding N, N-dimethylacetamide, heating to 35-37 ℃ while stirring, preserving heat, reacting until the raw material disappears, stopping the reaction, cooling to below 15 ℃, and sequentially performing suction filtration, water washing and drying to obtain a light yellow solid, namely 1-phenyl-3- (1,2, 3-thiadiazole-5-yl) urea; the reaction equation is as follows:
example 1
This example provides a method for preparing 1-phenyl-3- (1,2, 3-thiadiazol-5-yl) urea, comprising the steps of:
taking 1mol of 5-amino-1.2.3-thiadiazole as a raw material, adding 610ml of acetonitrile solvent, dropwise adding 1.01mol of phenyl isocyanate while stirring, cooling and reacting, adding triethylamine after dropwise adding, heating to 35 ℃ while stirring, preserving heat, reacting until the raw material disappears, stopping the reaction, cooling to 13 ℃, sequentially performing suction filtration, water washing and drying to obtain 206g of light yellow solid with a melting point of mp212-224 ℃ and a yield of 93.63%, wherein the light yellow solid is 1-phenyl-3- (1,2, 3-thiadiazole-5-yl) urea, recovering acetonitrile from mother liquor, removing water by phosphorus pentoxide, and the solvent recovery rate is 85.6%; the reaction equation is as follows:
example 2
This example provides a method for preparing 1-phenyl-3- (1,2, 3-thiadiazol-5-yl) urea, comprising the steps of:
adding 102g of dried 5-amino-1.2.3-thiadiazole into a dried reactor, adding 500ml of anhydrous toluene, dropwise adding 120.5g of phenyl isocyanate while stirring, completing dropwise adding of the phenyl isocyanate within 1 hour, simultaneously adding cold water into a jacket layer of the reactor, cooling to 30 ℃, preserving heat and reacting, adding 1g of catalyst monomethylamine after dropwise adding, then adding 10g of N, N-dimethylacetamide, stirring for 15 minutes, closing cooling water, slowly heating to 36 ℃, preserving heat and reacting for 4 hours until HPLC detection raw materials disappear, stopping reaction, cooling to 10 ℃, sequentially performing suction filtration, water washing and drying to obtain 216g of light yellow solid, wherein the melting point mp is 212-224 ℃, the yield is 98.1%, and the light yellow solid is 1-phenyl-3- (1,2, 3-thiadiazole-5-yl) urea, recovering toluene from the mother liquor at normal pressure, circularly removing water from the toluene, recovering the toluene for reuse, and finally recovering the N, N-dimethylacetamide for reuse under reduced pressure. The solvent was recovered with a 95.5% utilization.
Example 3
This example provides a method for preparing 1-phenyl-3- (1,2, 3-thiadiazol-5-yl) urea, comprising the steps of:
adding 102g of dried 5-amino-1.2.3-thiadiazole into a dried reactor, adding 700ml of tetrahydrofuran, dropwise adding 1.2mol of phenyl isocyanate while stirring, completing dropwise adding of the phenyl isocyanate within 1 hour, simultaneously adding cold water into a jacket layer of the reactor, cooling to 35 ℃, preserving heat and reacting, adding 1g of catalyst n-butylamine after finishing dropwise adding, stirring for 18 minutes after finishing adding, closing cooling water, slowly heating to 37 ℃, preserving heat and reacting for 4.2 hours, stopping the reaction until HPLC detection of the raw materials completely reacts, cooling to 10 ℃, sequentially performing suction filtration, water washing and drying to obtain 209g of light yellow solid, wherein the melting point is mp-224 ℃, the yield is 97.9%, the light yellow solid is 1-phenyl-3- (1,2, 3-thiadiazole-5-yl) urea, recovering mother liquor at normal pressure, removing peroxide, and (4) removing water, wherein the recovery utilization rate of the solvent is 80.3%.
The above description is only for the specific embodiments of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present invention, and all the changes or substitutions should be covered within the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the appended claims.
Claims (10)
1. A method for preparing 1-phenyl-3- (1,2, 3-thiadiazol-5-yl) urea, comprising the steps of:
taking 5 amino-1, 2, 3-thiadiazole as a raw material, adding an anhydrous organic solvent, dropwise adding phenyl isocyanate while stirring, cooling and reacting,after the dropwise addition is finished, adding a catalyst, adding N, N-dimethylacetamide, heating to 35-37 ℃ while stirring, preserving heat, reacting until the raw materials disappear, stopping the reaction, cooling to below 15 ℃, and sequentially performing suction filtration, washing and drying to obtain a light yellow solid, namely the 1-phenyl-3- (1,2, 3-thiadiazole-5-yl) urea; the reaction equation is as follows:
。
2. the method of claim 1-phenyl-3- (1,2, 3-thiadiazol-5-yl) urea, wherein said anhydrous organic solvent is anhydrous toluene.
3. The method of claim 2, wherein the anhydrous toluene is added in an amount of 1mol of the 5 amino-1.2.3-thiadiazole and 400 ml of the anhydrous toluene are added.
4. The method for producing 1-phenyl-3- (1,2, 3-thiadiazol-5-yl) urea according to claim 1, wherein the molar ratio of the 5 amino-1.2.3-thiadiazole to the amount of the phenyl isocyanate added is 1 (1-1.2).
5. The method for producing 1-phenyl-3- (1,2, 3-thiadiazol-5-yl) urea according to claim 1 or 4, wherein said phenyl isocyanate is added dropwise over 1 hour.
6. The method for producing 1-phenyl-3- (1,2, 3-thiadiazol-5-yl) urea according to claim 1, wherein phenyl isocyanate is added dropwise with stirring, the temperature is lowered and the reaction is carried out, the reaction temperature is maintained at 30 to 38 ℃ until the end of the addition.
7. The method for preparing 1-phenyl-3- (1,2, 3-thiadiazol-5-yl) urea according to claim 1 or 6, wherein said cooling is carried out by cooling with cold water in the jacket layer of the reactor.
8. The method for preparing 1-phenyl-3- (1,2, 3-thiadiazole-5-yl) urea according to claim 1, wherein N.N-dimethylacetamide is added, the mixture is heated to 35-37 ℃ while stirring, the temperature is maintained, and the reaction is carried out for 3.5-4.5 hours until the raw materials are completely reacted.
9. The method of claim 1 or 8, wherein HPLC is used to determine the completion of the reaction of the starting materials.
10. The method of claim 1, wherein the catalyst is triethylamine, monomethylamine, or n-butylamine.
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| CN202010614804.6A CN111763183A (en) | 2020-06-30 | 2020-06-30 | Preparation method of 1-phenyl-3- (1,2, 3-thiadiazole-5-yl) urea |
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| CN202010614804.6A CN111763183A (en) | 2020-06-30 | 2020-06-30 | Preparation method of 1-phenyl-3- (1,2, 3-thiadiazole-5-yl) urea |
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Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101386601A (en) * | 2008-09-24 | 2009-03-18 | 江苏省农用激素工程技术研究中心有限公司 | Method for preparing thidiazuron |
| CN101691362A (en) * | 2009-09-17 | 2010-04-07 | 扬州市天平化工厂有限公司 | Method for preparing N-phenyl-N-(1,2,3-thiadiazole) urea |
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2020
- 2020-06-30 CN CN202010614804.6A patent/CN111763183A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101386601A (en) * | 2008-09-24 | 2009-03-18 | 江苏省农用激素工程技术研究中心有限公司 | Method for preparing thidiazuron |
| CN101691362A (en) * | 2009-09-17 | 2010-04-07 | 扬州市天平化工厂有限公司 | Method for preparing N-phenyl-N-(1,2,3-thiadiazole) urea |
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