CN100475794C - Method for preparing 2-quinoxaline alcohol - Google Patents
Method for preparing 2-quinoxaline alcohol Download PDFInfo
- Publication number
- CN100475794C CN100475794C CNB2004100225228A CN200410022522A CN100475794C CN 100475794 C CN100475794 C CN 100475794C CN B2004100225228 A CNB2004100225228 A CN B2004100225228A CN 200410022522 A CN200410022522 A CN 200410022522A CN 100475794 C CN100475794 C CN 100475794C
- Authority
- CN
- China
- Prior art keywords
- quinoxaline
- hydrogen
- general formula
- expression
- reaction
- 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 - Fee Related
Links
- 238000000034 method Methods 0.000 title claims description 20
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 title abstract 2
- 229910021126 PdPt Inorganic materials 0.000 claims abstract description 4
- 238000006243 chemical reaction Methods 0.000 claims description 28
- 239000001257 hydrogen Substances 0.000 claims description 21
- 229910052739 hydrogen Inorganic materials 0.000 claims description 21
- 125000000449 nitro group Chemical group [O-][N+](*)=O 0.000 claims description 15
- 150000001875 compounds Chemical class 0.000 claims description 14
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 claims description 13
- 239000003054 catalyst Substances 0.000 claims description 10
- 229910004298 SiO 2 Inorganic materials 0.000 claims description 6
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 6
- KDLHZDBZIXYQEI-UHFFFAOYSA-N palladium Substances [Pd] KDLHZDBZIXYQEI-UHFFFAOYSA-N 0.000 claims description 6
- 150000008044 alkali metal hydroxides Chemical class 0.000 claims description 5
- 239000007864 aqueous solution Substances 0.000 claims description 4
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Substances [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 claims description 4
- 238000002360 preparation method Methods 0.000 claims description 4
- VHUUQVKOLVNVRT-UHFFFAOYSA-N Ammonium hydroxide Chemical compound [NH4+].[OH-] VHUUQVKOLVNVRT-UHFFFAOYSA-N 0.000 claims description 3
- 229910001860 alkaline earth metal hydroxide Inorganic materials 0.000 claims description 3
- 239000000908 ammonium hydroxide Substances 0.000 claims description 3
- 229910052697 platinum Inorganic materials 0.000 claims description 3
- 229910052742 iron Inorganic materials 0.000 claims description 2
- 125000004432 carbon atom Chemical group C* 0.000 claims 2
- 229910052736 halogen Inorganic materials 0.000 claims 2
- 150000002367 halogens Chemical class 0.000 claims 2
- 150000002431 hydrogen Chemical class 0.000 claims 2
- 125000004385 trihaloalkyl group Chemical group 0.000 claims 2
- 238000009903 catalytic hydrogenation reaction Methods 0.000 claims 1
- OMEXLMPRODBZCG-UHFFFAOYSA-N iron rhodium Chemical compound [Fe].[Rh] OMEXLMPRODBZCG-UHFFFAOYSA-N 0.000 claims 1
- JRTYPQGPARWINR-UHFFFAOYSA-N palladium platinum Chemical compound [Pd].[Pt] JRTYPQGPARWINR-UHFFFAOYSA-N 0.000 claims 1
- 230000002829 reductive effect Effects 0.000 abstract description 11
- 238000004519 manufacturing process Methods 0.000 abstract description 2
- 238000006555 catalytic reaction Methods 0.000 abstract 1
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 30
- 239000000243 solution Substances 0.000 description 16
- ZAMOUSCENKQFHK-UHFFFAOYSA-N Chlorine atom Chemical compound [Cl] ZAMOUSCENKQFHK-UHFFFAOYSA-N 0.000 description 13
- 239000000460 chlorine Substances 0.000 description 13
- 229910052801 chlorine Inorganic materials 0.000 description 13
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 12
- 238000003756 stirring Methods 0.000 description 11
- 239000007787 solid Substances 0.000 description 10
- SJAZZQLTKBYDHN-UHFFFAOYSA-N 6-chloro-1h-quinoxalin-2-one Chemical compound C1=C(Cl)C=CC2=NC(O)=CN=C21 SJAZZQLTKBYDHN-UHFFFAOYSA-N 0.000 description 8
- 239000003795 chemical substances by application Substances 0.000 description 7
- 239000000047 product Substances 0.000 description 7
- 238000001035 drying Methods 0.000 description 6
- 230000008030 elimination Effects 0.000 description 6
- 238000003379 elimination reaction Methods 0.000 description 6
- 239000000706 filtrate Substances 0.000 description 6
- 125000004435 hydrogen atom Chemical group [H]* 0.000 description 6
- 229910052757 nitrogen Inorganic materials 0.000 description 6
- 239000010948 rhodium Substances 0.000 description 6
- 238000005406 washing Methods 0.000 description 6
- 238000004587 chromatography analysis Methods 0.000 description 5
- 238000010790 dilution Methods 0.000 description 5
- 239000012895 dilution Substances 0.000 description 5
- 239000007791 liquid phase Substances 0.000 description 5
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 5
- NPXOKRUENSOPAO-UHFFFAOYSA-N Raney nickel Chemical compound [Al].[Ni] NPXOKRUENSOPAO-UHFFFAOYSA-N 0.000 description 3
- 229910052763 palladium Inorganic materials 0.000 description 3
- -1 6-chloro-2-hydroxy quinoxaline-4-oxide compound Chemical class 0.000 description 2
- OAKJQQAXSVQMHS-UHFFFAOYSA-N Hydrazine Chemical compound NN OAKJQQAXSVQMHS-UHFFFAOYSA-N 0.000 description 2
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 2
- 239000006227 byproduct Substances 0.000 description 2
- 238000001816 cooling Methods 0.000 description 2
- 230000006837 decompression Effects 0.000 description 2
- 238000005984 hydrogenation reaction Methods 0.000 description 2
- 230000035484 reaction time Effects 0.000 description 2
- 238000007363 ring formation reaction Methods 0.000 description 2
- 238000010792 warming Methods 0.000 description 2
- AVRPFRMDMNDIDH-UHFFFAOYSA-N 1h-quinazolin-2-one Chemical compound C1=CC=CC2=NC(O)=NC=C21 AVRPFRMDMNDIDH-UHFFFAOYSA-N 0.000 description 1
- 101100232929 Caenorhabditis elegans pat-4 gene Proteins 0.000 description 1
- 239000003905 agrochemical Substances 0.000 description 1
- 239000003513 alkali Substances 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 230000003197 catalytic effect Effects 0.000 description 1
- 239000003814 drug Substances 0.000 description 1
- 229940079593 drug Drugs 0.000 description 1
- ZZUFCTLCJUWOSV-UHFFFAOYSA-N furosemide Chemical compound C1=C(Cl)C(S(=O)(=O)N)=CC(C(O)=O)=C1NCC1=CC=CO1 ZZUFCTLCJUWOSV-UHFFFAOYSA-N 0.000 description 1
- 125000000623 heterocyclic group Chemical group 0.000 description 1
- 238000009776 industrial production Methods 0.000 description 1
- 230000008595 infiltration Effects 0.000 description 1
- 238000001764 infiltration Methods 0.000 description 1
- 239000000543 intermediate Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 229910052759 nickel Inorganic materials 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 230000009257 reactivity Effects 0.000 description 1
- 229910052703 rhodium Inorganic materials 0.000 description 1
- MHOVAHRLVXNVSD-UHFFFAOYSA-N rhodium atom Chemical compound [Rh] MHOVAHRLVXNVSD-UHFFFAOYSA-N 0.000 description 1
- 150000003839 salts Chemical class 0.000 description 1
- 239000012279 sodium borohydride Substances 0.000 description 1
- 229910000033 sodium borohydride Inorganic materials 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000003786 synthesis reaction Methods 0.000 description 1
Landscapes
- Low-Molecular Organic Synthesis Reactions Using Catalysts (AREA)
Abstract
A process for preparing 2-quinoxaline alcohol features that the 2-quinoxaline alcohol-4-oxide is selectively reduced by H2 in alkaline medium under the catalysis of carried PhFe or PdPt to obtain the product.
Description
2-quinoxaline compound such as 6-chloro-2-hydroxy quinoxaline are the intermediates of known production drug chemical of people and agrochemicals.These compounds generally prepare through the selective reduction of 2-quinoxaline-4-oxide compound.
Ishikura is in U.S. Pat 4,620, disclose in 003 2-quinoxaline-4-oxide compound has been reduced to the method for 2-quinoxaline compound, this method is used blue Buddhist nun's catalyzer (special Raney Ni or sulfurized Raney Ni), at alkali metal hydroxide, under the existence of alkaline earth metal hydroxides or ammonium hydroxide, do reductive agent and 2-quinoxaline-4-oxide compound reaction with hydrazine.
Kouichi is at Japanese Patent JP57,188,575 disclose with sodium borohydride and have made reductive agent, in alkali metal hydroxide aqueous solution, reductase 12-quinoxaline-4-oxide compound is the method for 2-quinoxaline compound, this method reduction efficiency is higher relatively, have industrial production and be worth, but the price of reductive agent borohydride salts is higher.
Davis is in U.S. Pat 4,636, discloses a kind of method in 562.Comprise in this method that making reductive agent reduction 6-chloro-2-hydroxy quinoxaline-4-oxide compound with hydrogen is 6-chloro-2-hydroxy quinoxaline step (at alkali metal hydroxide aqueous solution and transiting metal hydro catalyst preferably in the presence of the Raney Ni).This method is carried out at 0.1～0.4MPa hydrogen pressure, and preferably under 0.1～0.4MPa hydrogen-pressure.Under low hydrogen-pressure, there is the danger of air infiltration system, if hydrogen contacts hydrogenation catalyst together with oxygen, will produce blast.
People such as Sakata are at the Facile one-step synthesis of 2-(1H)-quinazolinone " 6-replaces-" [Heterocycles, Vol., 23, No.1 (1985)] narrated with hydrogen in the literary composition and made reductive agent, make catalyzer with palladium, 6-chloro-2-quinoxaline-4-oxide compound is reduced into the method for 6-chloro-2-quinoxaline, yet, people such as Sakata point out that this method can't overcome the generation of reduction by product.
People such as Rusell E. are in U.S. Pat 4, disclose a kind of method in 814,444, adopted hydrogen to make reductive agent, sulfurized platinum, palladium, nail, rhodium, nickel etc. are as catalyzer, reductase 12-quinoxaline-4-oxide compound is the 2-quinoxaline, and this method reduction selectivity improves a lot, and has reduced the generation of by product.But this method catalytic activity is not high, long reaction time, and yield is lower, only is 78% (based on the adjacent nitro alpha.-acetylacetanilide of chlorine is converted into 6-chloro-2-hydroxy quinoxaline).
Purpose of the present invention is made reductive agent with hydrogen exactly, and high reactivity, highly selective reductase 12-quinoxaline-4-oxide compound prepare the 2-quinoxaline.
The object of the present invention is achieved like this: being raw material to the adjacent nitro alpha.-acetylacetanilide of chlorine, prepare 2-quinoxaline-4-oxide compound through ring-closure reaction under alkaline condition, this oxide compound can also can directly move in the autoclave through separating, and adds catalyzer, use nitrogen wash still three times earlier, use hydrogen exchange again three times, be warming up to preset temperature, add hydrogen to predetermined pressure, stirring reaction is after for some time, cooling, reaction solution is shifted out in pressure release.The elimination catalyzer, filtrate is used hcl acidifying, and product is separated out, filter, washing, drying promptly gets product.
Catalyzer of the present invention is RhFe or the PdPt bimetallic catalyst that supports, and catalyzer is formed Rh content 0.5～5%, Fe content 1～10%, and Pd content 1～5%, Pt content 1～10%, carrier are SiO
2, Al
2O
3, and active C.The RhFe catalyzer that preferably supports, carrier is preferably SiO
2With active C.Catalyst consumption is the catalyzer that 2-quinoxaline-4-oxide compound of per 100 parts of weights weighs with about 0.5-50 part.
The reaction conditions of method of the present invention typically carries out under about 0.5～10MPa hydrogen-pressure, preferably carries out under about 0.5～5MPa hydrogen-pressure, and temperature of reaction is at 10-120 ℃, preferably about 25-75 ℃.About 3 hours of reaction times.
In the method for the present invention to the adjacent nitro alpha.-acetylacetanilide of chlorine ring-closure reaction under alkaline condition, used alkali is alkali metal hydroxide, the aqueous solution of alkaline earth metal hydroxides or ammonium hydroxide.
Be embodiments of the invention below:
Embodiment 1:
6.5g to the adjacent nitro alpha.-acetylacetanilide (95%) of chlorine, is added in 13.5% the aqueous sodium hydroxide solution (containing sodium hydroxide 5.0g) 60 ℃ of stirring reactions 1.0 hours.This reaction solution is directly moved in the autoclave, with the dilution of 50ml water, drop into the 65mgPd-Pt/C hydrogenation catalyst, at first use the nitrogen wash still three times, use hydrogen exchange again three times, be warming up to 80～90 ℃, add hydrogen to 1.3MPa, stirring reaction is after 2 hours.Cooling, reaction solution is shifted out in pressure release.The elimination catalyzer, filtrate is used hcl acidifying, has solid to separate out, filter washing, drying, get the light orange solid, efficient liquid phase chromatographic analysis product purity 85.8%, productive rate 87.7% (the adjacent nitro alpha.-acetylacetanilide of chlorine is converted into the molar yield of 6-chloro-2-hydroxy quinoxaline).
Embodiment 2:
6.5g to the adjacent nitro alpha.-acetylacetanilide (95%) of chlorine, is added in 13.5% the aqueous sodium hydroxide solution (containing sodium hydroxide 5.0g) 60 ℃ of stirring reactions 1.0 hours.This reaction solution is directly moved in the autoclave,, drop into Rh with the dilution of 50ml water
0.008Fe
0.03/ SiO
2The 125mg catalyzer is at first used the nitrogen wash still three times, uses hydrogen exchange again three times, heats up 80～90 ℃, adds hydrogen to 1.3MPa, and stirring reaction cooled after 2 hours, and reaction solution is shifted out in pressure release.The elimination catalyzer, filtrate is used hcl acidifying, has solid to separate out, and filters, washing, drying gets the light orange solid, efficient liquid phase chromatographic analysis, product purity 〉=96.0% content, productive rate 95.1% (the adjacent nitro alpha.-acetylacetanilide of chlorine is converted into the molar yield of 6-chloro-2-hydroxy quinoxaline).
Embodiment 3:
6.5g to the adjacent nitro alpha.-acetylacetanilide (95%) of chlorine, is added in 13.5% the aqueous sodium hydroxide solution (containing sodium hydroxide 5.0g) 60 ℃ of stirring reactions 1.0 hours.This reaction solution is directly moved in the autoclave,, drop into Rh with the dilution of 50ml water
0.008Fe
0.03/ SiO
2The 125mg catalyzer is at first used the nitrogen wash still three times, uses hydrogen exchange again three times, heats up 105～110 ℃, adds hydrogen to 1.3MPa, and stirring reaction cooled after 1.3 hours, and reaction solution is shifted out in pressure release.The elimination catalyzer, filtrate is used hcl acidifying, has solid to separate out, and filters, washing, drying gets the light orange solid, efficient liquid phase chromatographic analysis, product purity 〉=96.0% content, productive rate 92.1% (the adjacent nitro alpha.-acetylacetanilide of chlorine is converted into the molar yield of 6-chloro-2-hydroxy quinoxaline).
Embodiment 4:
6.5g to the adjacent nitro alpha.-acetylacetanilide (95%) of chlorine, is added in 13.5% the aqueous sodium hydroxide solution (containing sodium hydroxide 5.0g) 60 ℃ of stirring reactions 1.0 hours.This reaction solution is directly moved in the autoclave,, drop into Rh with the dilution of 50ml water
0.008Fe
0.03/ SiO
2The 150mg catalyzer is at first used the nitrogen wash still three times, uses hydrogen exchange again three times, heats up 80～90 ℃, adds hydrogen to 2.5MPa, and stirring reaction cooled after 1 hour, and reaction solution is shifted out in decompression.The elimination catalyzer, filtrate is used hcl acidifying, has solid to separate out, and filters, washing, drying gets the light orange solid, efficient liquid phase chromatographic analysis, product purity 〉=96.0% content, productive rate 92.1% (the adjacent nitro alpha.-acetylacetanilide of chlorine is converted into the molar yield of 6-chloro-2-hydroxy quinoxaline).
Embodiment 5:
6.5g to the adjacent nitro alpha.-acetylacetanilide (95%) of chlorine, is added in 13.5% the aqueous sodium hydroxide solution (containing sodium hydroxide 5.0g) 60 ℃ of stirring reactions 1.0 hours.This reaction solution is directly moved in the autoclave,, drop into Rh with the dilution of 50ml water
0.01Fe
0.03/ Al
2O
3The 150mg catalyzer is at first used the nitrogen wash still three times, uses hydrogen exchange again three times, heats up 80～90 ℃, adds hydrogen to 1.3MPa, and stirring reaction cooled after 3 hours, and reaction solution is shifted out in decompression.The elimination catalyzer, filtrate is used hcl acidifying, has solid to separate out, and filters, washing, drying gets the light orange solid, efficient liquid phase chromatographic analysis, product purity 〉=92.0% content, productive rate 90.1% (the adjacent nitro alpha.-acetylacetanilide of chlorine is converted into the molar yield of 6-chloro-2-hydroxy quinoxaline).
Claims (8)
1. the preparation method of the 2-quinoxaline of a general formula (1) expression is characterized in that, is supporting in the presence of rhodium-iron or the palladium-platinum catalyst, makes 2-quinoxaline-4-oxide compound and hydrogen reaction with general formula (2) expression prepare the 2-quinoxaline of general formula (1) expression,
In the formula, R is that hydrogen, halogen, trihalogenmethyl, nitro or carbonatoms are the tri haloalkyl of 2-5.
2. the preparation method of the 2-quinoxaline of a kind of general formula according to claim 1 (1) expression is characterized in that catalyst system therefor is the RhFe that supports, and catalyzer is formed Rh content 0.5～5%, Fe content 1～10%.
3. the preparation method of the 2-quinoxaline of a kind of general formula according to claim 1 (1) expression is characterized in that catalyst system therefor is the PdPt bimetallic catalyst that supports, Pd content 1～5%, Pt content 1～10%.
4. method as claimed in claim 2 is characterized in that the RhFe that supports or the carrier of the PdPt bimetallic catalyst that supports is SiO
2, Al
2O
3Or active C.
5. method as claimed in claim 1 is characterized in that the R in the general formula (1) is that hydrogen, halogen, trihalogenmethyl, nitro or carbonatoms are the tri haloalkyl of 2-5.
6. method as claimed in claim 1 is characterized in that temperature of reaction is at 10-150 ℃.
7. method as claimed in claim 1 is characterized in that reaction pressure is under the hydrogen-pressure of 0.5-10MPa.
8. method as claimed in claim 1, it is characterized in that described 2-quinoxaline-4-oxide compound with general formula (2) expression is to be in to contain to be selected from alkali metal hydroxide, carry out catalytic hydrogenation reaction in the aqueous solution of at least a compound of alkaline earth metal hydroxides and ammonium hydroxide.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB2004100225228A CN100475794C (en) | 2004-05-14 | 2004-05-14 | Method for preparing 2-quinoxaline alcohol |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB2004100225228A CN100475794C (en) | 2004-05-14 | 2004-05-14 | Method for preparing 2-quinoxaline alcohol |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1696119A CN1696119A (en) | 2005-11-16 |
| CN100475794C true CN100475794C (en) | 2009-04-08 |
Family
ID=35349033
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNB2004100225228A Expired - Fee Related CN100475794C (en) | 2004-05-14 | 2004-05-14 | Method for preparing 2-quinoxaline alcohol |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN100475794C (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102180840A (en) * | 2011-03-15 | 2011-09-14 | 安徽丰乐农化有限责任公司 | New preparation process of 6-chloro-2-hydroxyquinoxaline |
| CN102108065B (en) * | 2011-03-23 | 2012-11-28 | 浙江禾田化工有限公司 | Method for preparing 2-quinoxalinol |
| CN114369069B (en) * | 2022-01-21 | 2024-03-15 | 江苏丰山生化科技有限公司 | Preparation method of quizalofop-p-ethyl compound intermediate |
-
2004
- 2004-05-14 CN CNB2004100225228A patent/CN100475794C/en not_active Expired - Fee Related
Non-Patent Citations (2)
| Title |
|---|
| 精喹禾灵中间体6-氯-2-喹喔啉醇的合成. 刘国凯，罗仕忠，杨先贵.合成化学，第6期. 2003 |
| 精喹禾灵中间体6-氯-2-喹喔啉醇的合成. 刘国凯，罗仕忠，杨先贵.合成化学，第6期. 2003 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN1696119A (en) | 2005-11-16 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP4523275B2 (en) | Supported catalysts for the hydrogenation of nitroaromatic compounds. | |
| CN109232271B (en) | Method for preparing o-phenylenediamine by catalytic reduction of o-nitroaniline | |
| JP2009527524A (en) | Method for direct amination of hydrocarbons | |
| CN101081825A (en) | Method for hydrogenation preparation of m-(beta-hydroxyethyl sulfone)aniline by amorphous alloy nickel catalysis of m-(beta-hydroxyethyl sulfone) nitrobenzene | |
| CN101489978A (en) | Direct amination of hydrocarbons | |
| CN103214392A (en) | Synthetic method of N-benzylideneaniline compound | |
| CN100475794C (en) | Method for preparing 2-quinoxaline alcohol | |
| CN106543017B (en) | A kind of preparation method of 4 aminocyclohexyl acetic acid | |
| CA2280511C (en) | Production of 1,3-diaminopentane by hydrogenation of 3-aminopentanenitrile | |
| IL106216A (en) | omega-Substituted-phenyl cyclopropyl ketones as herbicide intermediates and a method for their prep ration | |
| US6818720B2 (en) | Supported hydrogenating catalyst in powder form | |
| CN101092367B (en) | Method for preparing 4,6 diamino resorcin, and its hydrochlorate | |
| EP1351920A1 (en) | Process for the preparation of substituted amines by hydrogenation of substituted organic nitro compounds | |
| CN101475488B (en) | Method for preparing aminotoluene by catalytic hydrogenation of 2,4-dinitrotoluene or/and 2,6-dinitrotoluene | |
| CN102108065B (en) | Method for preparing 2-quinoxalinol | |
| CA2440518C (en) | Method of producing n-substituted 2,6-dialkyl morpholines | |
| AU601851B2 (en) | Process for the production of 2-quinoxalines | |
| JPH11335385A (en) | Transition metal complex and production of optically active alcohol using the same | |
| CN102603622B (en) | Synthetic method of 2-amino-4-bromopyridine | |
| KR100971893B1 (en) | Supported catalyst for hydrogenation of nitroaromatics | |
| CN101643428A (en) | Method for preparing 3,3'-dimethoxybenzidine hydrochloride | |
| CN105949033A (en) | Method for preparing 1,4-cyclohexanediol from p-benzoquinone through catalytic hydrogenation | |
| JPS59190975A (en) | Production of 2-alkyl-4-amino-5-aminomethylpyrimidine | |
| CN113816891A (en) | Synthesis method of 5, 6-dihydroxyindole and derivatives thereof | |
| KR100645667B1 (en) | Process for producing 1-n-halophenylethanol |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C17 | Cessation of patent right | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20090408 Termination date: 20120514 |