CN111302955A - Synthesis method of aminophenol - Google Patents
Synthesis method of aminophenol Download PDFInfo
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- CN111302955A CN111302955A CN202010268018.5A CN202010268018A CN111302955A CN 111302955 A CN111302955 A CN 111302955A CN 202010268018 A CN202010268018 A CN 202010268018A CN 111302955 A CN111302955 A CN 111302955A
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- Prior art keywords
- aminophenol
- nitrophenol
- catalyst
- reaction
- dichloro
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- CDAWCLOXVUBKRW-UHFFFAOYSA-N 2-aminophenol Chemical compound NC1=CC=CC=C1O CDAWCLOXVUBKRW-UHFFFAOYSA-N 0.000 title claims abstract description 60
- 238000001308 synthesis method Methods 0.000 title abstract description 9
- 238000006243 chemical reaction Methods 0.000 claims abstract description 91
- IQUPABOKLQSFBK-UHFFFAOYSA-N 2-nitrophenol Chemical compound OC1=CC=CC=C1[N+]([O-])=O IQUPABOKLQSFBK-UHFFFAOYSA-N 0.000 claims abstract description 40
- 239000012752 auxiliary agent Substances 0.000 claims abstract description 40
- 239000002904 solvent Substances 0.000 claims abstract description 33
- 239000001257 hydrogen Substances 0.000 claims abstract description 16
- 229910052739 hydrogen Inorganic materials 0.000 claims abstract description 16
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 claims abstract description 15
- 239000003054 catalyst Substances 0.000 claims description 66
- 238000000034 method Methods 0.000 claims description 66
- 238000005984 hydrogenation reaction Methods 0.000 claims description 51
- 239000012295 chemical reaction liquid Substances 0.000 claims description 47
- PXSGFTWBZNPNIC-UHFFFAOYSA-N 618-80-4 Chemical compound OC1=C(Cl)C=C([N+]([O-])=O)C=C1Cl PXSGFTWBZNPNIC-UHFFFAOYSA-N 0.000 claims description 44
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 claims description 40
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 claims description 39
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 34
- 230000008569 process Effects 0.000 claims description 28
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims description 22
- QTBSBXVTEAMEQO-UHFFFAOYSA-N Acetic acid Chemical compound CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 claims description 21
- LRHPLDYGYMQRHN-UHFFFAOYSA-N N-Butanol Chemical compound CCCCO LRHPLDYGYMQRHN-UHFFFAOYSA-N 0.000 claims description 20
- KFZMGEQAYNKOFK-UHFFFAOYSA-N Isopropanol Chemical compound CC(C)O KFZMGEQAYNKOFK-UHFFFAOYSA-N 0.000 claims description 18
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 claims description 18
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 claims description 18
- 238000004821 distillation Methods 0.000 claims description 18
- 230000002194 synthesizing effect Effects 0.000 claims description 17
- KWYUFKZDYYNOTN-UHFFFAOYSA-M Potassium hydroxide Chemical compound [OH-].[K+] KWYUFKZDYYNOTN-UHFFFAOYSA-M 0.000 claims description 15
- IAZDPXIOMUYVGZ-UHFFFAOYSA-N Dimethylsulphoxide Chemical compound CS(C)=O IAZDPXIOMUYVGZ-UHFFFAOYSA-N 0.000 claims description 14
- CDBYLPFSWZWCQE-UHFFFAOYSA-L Sodium Carbonate Chemical compound [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 claims description 14
- WYURNTSHIVDZCO-UHFFFAOYSA-N Tetrahydrofuran Chemical compound C1CCOC1 WYURNTSHIVDZCO-UHFFFAOYSA-N 0.000 claims description 14
- KDLHZDBZIXYQEI-UHFFFAOYSA-N Palladium Chemical compound [Pd] KDLHZDBZIXYQEI-UHFFFAOYSA-N 0.000 claims description 13
- 238000001035 drying Methods 0.000 claims description 13
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 claims description 13
- 239000000126 substance Substances 0.000 claims description 13
- 238000000926 separation method Methods 0.000 claims description 12
- 239000003795 chemical substances by application Substances 0.000 claims description 11
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 claims description 10
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims description 9
- 230000009471 action Effects 0.000 claims description 9
- 230000001376 precipitating effect Effects 0.000 claims description 9
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 8
- 239000002253 acid Substances 0.000 claims description 8
- 239000007788 liquid Substances 0.000 claims description 8
- BDAGIHXWWSANSR-UHFFFAOYSA-N methanoic acid Natural products OC=O BDAGIHXWWSANSR-UHFFFAOYSA-N 0.000 claims description 8
- 229910000510 noble metal Inorganic materials 0.000 claims description 8
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 claims description 7
- 229910017604 nitric acid Inorganic materials 0.000 claims description 7
- 229910000029 sodium carbonate Inorganic materials 0.000 claims description 7
- YLQBMQCUIZJEEH-UHFFFAOYSA-N tetrahydrofuran Natural products C=1C=COC=1 YLQBMQCUIZJEEH-UHFFFAOYSA-N 0.000 claims description 7
- UIIMBOGNXHQVGW-UHFFFAOYSA-M Sodium bicarbonate Chemical compound [Na+].OC([O-])=O UIIMBOGNXHQVGW-UHFFFAOYSA-M 0.000 claims description 6
- BWHMMNNQKKPAPP-UHFFFAOYSA-L potassium carbonate Chemical compound [K+].[K+].[O-]C([O-])=O BWHMMNNQKKPAPP-UHFFFAOYSA-L 0.000 claims description 6
- 239000010948 rhodium Substances 0.000 claims description 6
- 229910052759 nickel Inorganic materials 0.000 claims description 5
- 229910052763 palladium Inorganic materials 0.000 claims description 5
- 229910052697 platinum Inorganic materials 0.000 claims description 5
- 229910052703 rhodium Inorganic materials 0.000 claims description 5
- MHOVAHRLVXNVSD-UHFFFAOYSA-N rhodium atom Chemical compound [Rh] MHOVAHRLVXNVSD-UHFFFAOYSA-N 0.000 claims description 5
- 239000000377 silicon dioxide Substances 0.000 claims description 5
- OSWFIVFLDKOXQC-UHFFFAOYSA-N 4-(3-methoxyphenyl)aniline Chemical compound COC1=CC=CC(C=2C=CC(N)=CC=2)=C1 OSWFIVFLDKOXQC-UHFFFAOYSA-N 0.000 claims description 4
- VHUUQVKOLVNVRT-UHFFFAOYSA-N Ammonium hydroxide Chemical compound [NH4+].[OH-] VHUUQVKOLVNVRT-UHFFFAOYSA-N 0.000 claims description 4
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 claims description 4
- 235000011114 ammonium hydroxide Nutrition 0.000 claims description 4
- AXCZMVOFGPJBDE-UHFFFAOYSA-L calcium dihydroxide Chemical compound [OH-].[OH-].[Ca+2] AXCZMVOFGPJBDE-UHFFFAOYSA-L 0.000 claims description 4
- 239000000920 calcium hydroxide Substances 0.000 claims description 4
- 229910001861 calcium hydroxide Inorganic materials 0.000 claims description 4
- 235000019253 formic acid Nutrition 0.000 claims description 4
- 239000007791 liquid phase Substances 0.000 claims description 4
- 238000005191 phase separation Methods 0.000 claims description 4
- 239000012065 filter cake Substances 0.000 claims description 3
- 239000003960 organic solvent Substances 0.000 claims description 3
- 229910000027 potassium carbonate Inorganic materials 0.000 claims description 3
- 229910000030 sodium bicarbonate Inorganic materials 0.000 claims description 3
- 235000017557 sodium bicarbonate Nutrition 0.000 claims description 3
- 125000005843 halogen group Chemical group 0.000 claims description 2
- 150000007529 inorganic bases Chemical class 0.000 claims description 2
- 238000001556 precipitation Methods 0.000 claims description 2
- 150000003839 salts Chemical class 0.000 claims description 2
- 125000001424 substituent group Chemical group 0.000 claims description 2
- 239000000047 product Substances 0.000 abstract description 25
- NWZSZGALRFJKBT-KNIFDHDWSA-N (2s)-2,6-diaminohexanoic acid;(2s)-2-hydroxybutanedioic acid Chemical compound OC(=O)[C@@H](O)CC(O)=O.NCCCC[C@H](N)C(O)=O NWZSZGALRFJKBT-KNIFDHDWSA-N 0.000 abstract description 13
- IKDUDTNKRLTJSI-UHFFFAOYSA-N hydrazine monohydrate Substances O.NN IKDUDTNKRLTJSI-UHFFFAOYSA-N 0.000 abstract description 13
- JVBXVOWTABLYPX-UHFFFAOYSA-L sodium dithionite Chemical compound [Na+].[Na+].[O-]S(=O)S([O-])=O JVBXVOWTABLYPX-UHFFFAOYSA-L 0.000 abstract description 11
- 239000003638 chemical reducing agent Substances 0.000 abstract description 10
- 238000007086 side reaction Methods 0.000 abstract description 8
- 239000002699 waste material Substances 0.000 abstract description 8
- 239000012467 final product Substances 0.000 abstract description 3
- 150000002431 hydrogen Chemical class 0.000 abstract 1
- KGEXISHTCZHGFT-UHFFFAOYSA-N 4-azaniumyl-2,6-dichlorophenolate Chemical compound NC1=CC(Cl)=C(O)C(Cl)=C1 KGEXISHTCZHGFT-UHFFFAOYSA-N 0.000 description 50
- 239000000243 solution Substances 0.000 description 42
- 239000008367 deionised water Substances 0.000 description 14
- 229910021641 deionized water Inorganic materials 0.000 description 14
- 238000007792 addition Methods 0.000 description 10
- 238000002425 crystallisation Methods 0.000 description 9
- 230000008025 crystallization Effects 0.000 description 9
- 239000007787 solid Substances 0.000 description 9
- 238000001816 cooling Methods 0.000 description 8
- 239000011259 mixed solution Substances 0.000 description 8
- 230000015572 biosynthetic process Effects 0.000 description 7
- 238000003786 synthesis reaction Methods 0.000 description 7
- 125000003277 amino group Chemical group 0.000 description 6
- UISUNVFOGSJSKD-UHFFFAOYSA-N chlorfluazuron Chemical compound FC1=CC=CC(F)=C1C(=O)NC(=O)NC(C=C1Cl)=CC(Cl)=C1OC1=NC=C(C(F)(F)F)C=C1Cl UISUNVFOGSJSKD-UHFFFAOYSA-N 0.000 description 6
- 238000001914 filtration Methods 0.000 description 6
- 125000002887 hydroxy group Chemical group [H]O* 0.000 description 6
- 230000009467 reduction Effects 0.000 description 6
- PLIKAWJENQZMHA-UHFFFAOYSA-N 4-aminophenol Chemical compound NC1=CC=C(O)C=C1 PLIKAWJENQZMHA-UHFFFAOYSA-N 0.000 description 4
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 4
- PXGOKWXKJXAPGV-UHFFFAOYSA-N Fluorine Chemical compound FF PXGOKWXKJXAPGV-UHFFFAOYSA-N 0.000 description 4
- FAPWRFPIFSIZLT-UHFFFAOYSA-M Sodium chloride Chemical compound [Na+].[Cl-] FAPWRFPIFSIZLT-UHFFFAOYSA-M 0.000 description 4
- 229910052731 fluorine Inorganic materials 0.000 description 4
- 239000011737 fluorine Substances 0.000 description 4
- 239000000575 pesticide Substances 0.000 description 4
- 238000010189 synthetic method Methods 0.000 description 4
- WKBOTKDWSSQWDR-UHFFFAOYSA-N Bromine atom Chemical compound [Br] WKBOTKDWSSQWDR-UHFFFAOYSA-N 0.000 description 3
- ZAMOUSCENKQFHK-UHFFFAOYSA-N Chlorine atom Chemical compound [Cl] ZAMOUSCENKQFHK-UHFFFAOYSA-N 0.000 description 3
- 150000003863 ammonium salts Chemical class 0.000 description 3
- GDTBXPJZTBHREO-UHFFFAOYSA-N bromine Substances BrBr GDTBXPJZTBHREO-UHFFFAOYSA-N 0.000 description 3
- 229910052794 bromium Inorganic materials 0.000 description 3
- 229910052801 chlorine Inorganic materials 0.000 description 3
- 239000000460 chlorine Substances 0.000 description 3
- 239000000203 mixture Substances 0.000 description 3
- 239000012071 phase Substances 0.000 description 3
- ZRJSABISRHPRSB-UHFFFAOYSA-N 2,6-difluorobenzoyl isocyanate Chemical compound FC1=CC=CC(F)=C1C(=O)N=C=O ZRJSABISRHPRSB-UHFFFAOYSA-N 0.000 description 2
- KCLWRVQIRVOVLJ-UHFFFAOYSA-N 3,5-dichloro-4-[3-chloro-5-(trifluoromethyl)pyridin-2-yl]oxyaniline Chemical compound ClC1=CC(N)=CC(Cl)=C1OC1=NC=C(C(F)(F)F)C=C1Cl KCLWRVQIRVOVLJ-UHFFFAOYSA-N 0.000 description 2
- HRYILSDLIGTCOP-UHFFFAOYSA-N N-benzoylurea Chemical compound NC(=O)NC(=O)C1=CC=CC=C1 HRYILSDLIGTCOP-UHFFFAOYSA-N 0.000 description 2
- 229910000564 Raney nickel Inorganic materials 0.000 description 2
- NPXOKRUENSOPAO-UHFFFAOYSA-N Raney nickel Chemical compound [Al].[Ni] NPXOKRUENSOPAO-UHFFFAOYSA-N 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 2
- 230000007613 environmental effect Effects 0.000 description 2
- 230000002401 inhibitory effect Effects 0.000 description 2
- PNDPGZBMCMUPRI-UHFFFAOYSA-N iodine Chemical compound II PNDPGZBMCMUPRI-UHFFFAOYSA-N 0.000 description 2
- 231100000053 low toxicity Toxicity 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 230000007935 neutral effect Effects 0.000 description 2
- 231100000956 nontoxicity Toxicity 0.000 description 2
- 238000006116 polymerization reaction Methods 0.000 description 2
- 238000004321 preservation Methods 0.000 description 2
- 239000002994 raw material Substances 0.000 description 2
- 239000011780 sodium chloride Substances 0.000 description 2
- ABNQGNFVSFKJGI-UHFFFAOYSA-N 2,3-dichloro-5-(trifluoromethyl)pyridine Chemical compound FC(F)(F)C1=CN=C(Cl)C(Cl)=C1 ABNQGNFVSFKJGI-UHFFFAOYSA-N 0.000 description 1
- AVRQBXVUUXHRMY-UHFFFAOYSA-N 2,6-difluorobenzamide Chemical compound NC(=O)C1=C(F)C=CC=C1F AVRQBXVUUXHRMY-UHFFFAOYSA-N 0.000 description 1
- BTJIUGUIPKRLHP-UHFFFAOYSA-N 4-nitrophenol Chemical compound OC1=CC=C([N+]([O-])=O)C=C1 BTJIUGUIPKRLHP-UHFFFAOYSA-N 0.000 description 1
- 229920002101 Chitin Polymers 0.000 description 1
- 241000238631 Hexapoda Species 0.000 description 1
- 241001465754 Metazoa Species 0.000 description 1
- YGYAWVDWMABLBF-UHFFFAOYSA-N Phosgene Chemical compound ClC(Cl)=O YGYAWVDWMABLBF-UHFFFAOYSA-N 0.000 description 1
- 240000005319 Sedum acre Species 0.000 description 1
- 235000014327 Sedum acre Nutrition 0.000 description 1
- UIIMBOGNXHQVGW-DEQYMQKBSA-M Sodium bicarbonate-14C Chemical compound [Na+].O[14C]([O-])=O UIIMBOGNXHQVGW-DEQYMQKBSA-M 0.000 description 1
- QAOWNCQODCNURD-UHFFFAOYSA-L Sulfate Chemical compound [O-]S([O-])(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-L 0.000 description 1
- 241000607479 Yersinia pestis Species 0.000 description 1
- 239000002671 adjuvant Substances 0.000 description 1
- 238000007605 air drying Methods 0.000 description 1
- 229910021529 ammonia Inorganic materials 0.000 description 1
- 238000005119 centrifugation Methods 0.000 description 1
- 229910052681 coesite Inorganic materials 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 238000006482 condensation reaction Methods 0.000 description 1
- 229910052906 cristobalite Inorganic materials 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000004090 dissolution Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000006266 etherification reaction Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 239000000706 filtrate Substances 0.000 description 1
- 238000004817 gas chromatography Methods 0.000 description 1
- 239000003630 growth substance Substances 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- RGNPBRKPHBKNKX-UHFFFAOYSA-N hexaflumuron Chemical compound C1=C(Cl)C(OC(F)(F)C(F)F)=C(Cl)C=C1NC(=O)NC(=O)C1=C(F)C=CC=C1F RGNPBRKPHBKNKX-UHFFFAOYSA-N 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 239000003112 inhibitor Substances 0.000 description 1
- 239000002917 insecticide Substances 0.000 description 1
- 238000004811 liquid chromatography Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000000361 pesticidal effect Effects 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 238000004445 quantitative analysis Methods 0.000 description 1
- 238000011084 recovery Methods 0.000 description 1
- 238000004064 recycling Methods 0.000 description 1
- 238000010992 reflux Methods 0.000 description 1
- 238000004062 sedimentation Methods 0.000 description 1
- 229910052682 stishovite Inorganic materials 0.000 description 1
- 238000003860 storage Methods 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 238000010998 test method Methods 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
- 231100000331 toxic Toxicity 0.000 description 1
- 230000002588 toxic effect Effects 0.000 description 1
- 231100000419 toxicity Toxicity 0.000 description 1
- 230000001988 toxicity Effects 0.000 description 1
- 238000012546 transfer Methods 0.000 description 1
- 229910052905 tridymite Inorganic materials 0.000 description 1
- 238000001291 vacuum drying Methods 0.000 description 1
- 238000005406 washing Methods 0.000 description 1
- 239000002351 wastewater Substances 0.000 description 1
- 238000004065 wastewater treatment Methods 0.000 description 1
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Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C213/00—Preparation of compounds containing amino and hydroxy, amino and etherified hydroxy or amino and esterified hydroxy groups bound to the same carbon skeleton
- C07C213/02—Preparation of compounds containing amino and hydroxy, amino and etherified hydroxy or amino and esterified hydroxy groups bound to the same carbon skeleton by reactions involving the formation of amino groups from compounds containing hydroxy groups or etherified or esterified hydroxy groups
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C213/00—Preparation of compounds containing amino and hydroxy, amino and etherified hydroxy or amino and esterified hydroxy groups bound to the same carbon skeleton
- C07C213/10—Separation; Purification; Stabilisation; Use of additives
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- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
The invention provides a synthesis method of aminophenol, which can prepare an aminophenol product with high selectivity and yield by reacting nitrophenol with hydrogen under the conditions of an auxiliary agent and a solvent, wherein the auxiliary agent can better control the reaction depth of the nitrophenol and the hydrogen, so that the side reaction is inhibited, the purity of a final product is improved, the problems of poor selectivity and large quantity of three wastes of reducing agents such as hydrazine hydrate, sodium hydrosulfite and the like commonly used in the prior art are solved, and the synthesis method has high industrial application value.
Description
Technical Field
The invention relates to the technical field of organic chemical industry, in particular to a synthetic method of aminophenol.
Background
Chlorfluazuron (CAS:71422-67-8) is a benzoyl urea type high-efficiency low-toxicity insecticide, and the compound is a benzoyl urea type chitin inhibitor discovered by Nippon stonecrop in 1982 and is a novel insect growth regulator. It has high pesticidal activity, low toxicity to human and animal, less environmental influence and high safety to natural enemy of predatory pests, and is one kind of efficient and low toxic pesticide product with high environment compatibility.
The synthesis of the chlorfluazuron takes 2, 6-dichloro-4-aminophenol and 2, 3-dichloro-5-trifluoromethylpyridine as raw materials to obtain 3, 5-dichloro-4- (3-chloro-5-trifluoromethyl-2-pyridyloxy) aniline through etherification reaction, 2, 6-difluorobenzamide reacts with solid phosgene to obtain 2, 6-difluorobenzoyl isocyanate, and the 3, 5-dichloro-4- (3-chloro-5-trifluoromethyl-2-pyridyloxy) aniline and the 2, 6-difluorobenzoyl isocyanate are subjected to condensation reaction to obtain the chlorfluazuron. This has led to the synthesis of 2, 6-dichloro-4-aminophenol, an intermediate thereof, being of increasing importance.
Rankine et al, 2012, discloses a process for the preparation of 2, 6-dichloro-4-aminophenol by reduction of 2, 6-dichloro-4-nitrophenol with hydrazine hydrate (see "synthesis of 2, 6-dichloro-4-aminophenol", Rankine et al, pesticides, Vol 51, No. 3, p 184-. Adding alcohol, 2, 6-dichloro-4-nitrophenol and a reduction catalyst H-C2 into a four-mouth bottle, heating to 75 ℃, and dropwise adding 80% hydrazine hydrate. After the dropwise addition, refluxing and heat preservation are carried out for 3h, the mixture is filtered while the mixture is hot, alcohol is evaporated from the filtrate, the mixture is cooled to room temperature, filtered and dried to obtain offwhite 2, 6-dichloro-4-aminophenol, and the purity of liquid chromatography is 99.2%. However, the reducing agent hydrazine hydrate adopted by the method has toxicity and strong reducibility, and the storage and use processes need extra care.
Zhongjin et al (1998) disclose a process for preparing 2, 6-dichloro-4-aminophenol by reducing 2, 6-dichloro-4-nitrophenol with sodium hydrosulfite (see "Synthesis of hexaflumuron, Zhongjin et al, chemical world, 9 th, pages 36-37). In the method, water, 2, 6-dichloro-4-nitrophenol and sodium carbonate are added into a four-mouth flask and heated and dissolved to obtain yellow reaction liquid. Adding sodium hydrosulfite in batches at 50-60 ℃, and reacting for 0.5h under heat preservation to generate a large amount of solid. Cooling to room temperature, filtering, washing with water, and drying to obtain 2, 6-dichloro-4-aminophenol with a yield of 75%. However, the method has low yield, the adopted reducing agent sodium hydrosulfite has poor stability and safety, and simultaneously sulfate wastewater is generated, so that the post-treatment difficulty is increased.
At present, methods for preparing 2, 6-dichloro-4-aminophenol by reducing 2, 6-dichloro-4-nitrophenol with hydrogen at home and abroad are rarely reported, mainly because of unstable products, poor reaction selectivity and great technical difficulty. Hydrazine hydrate, sodium hydrosulfite and the like are adopted as reducing agents, so that the process safety is poor, and the amount of three wastes is large.
Therefore, in order to solve the problems of the above processes, it is urgently needed to develop a stable hydrogenation synthesis technology to prepare aminophenol, and solve the problems of low yield, poor safety of reducing agents, great difficulty in wastewater treatment and the like in the prior art.
Disclosure of Invention
In view of the problems in the prior art, the invention provides a synthetic method of aminophenol, in particular to a synthetic method of 2, 6-dichloro-4-aminophenol as a chlorfluazuron intermediate, in the method, nitrophenol is directly subjected to hydrogenation reaction with hydrogen under the action of a catalyst, and the reaction depth and selectivity are controlled by adding an auxiliary agent, so that the purity and yield of a final product are improved, the problems of use of reducing agents such as hydrazine hydrate and sodium hydrosulfite and large discharge amount of three wastes are avoided, and the synthetic method has high industrial application value.
In order to achieve the purpose, the invention adopts the following technical scheme:
in a first aspect, the present invention provides a method for synthesizing an aminophenol, the method comprising: the nitrophenol and hydrogen are subjected to hydrogenation reaction under the action of a solvent, an auxiliary agent and a catalyst to generate the aminophenol.
The synthesis method of aminophenol provided by the invention directly adopts hydrogen as a reducing agent, has no pollution problem generated during reduction of substances such as hydrazine hydrate, sodium hydrosulfite and the like, and also has no toxicity problem during reduction of hydrazine hydrate, and has the advantages of simple post-treatment process, less side reaction, recyclable solvent and small difficulty in treatment of three wastes. The addition of the auxiliary agent can control the depth, conversion rate and selectivity of the hydrogenation reaction, reduce side reactions and improve the yield and purity of the final product.
Wherein the formula of the hydrogenation reaction is shown in the following formula (1):
preferably, the auxiliary in the method is an acid auxiliary.
The auxiliary agent provided by the invention is an acid auxiliary agent, and provides an acid environment for the reaction, so that the generated aminophenol can be converted into ammonium salt, the polymerization reaction between the amino group and the amino group, between the hydroxyl group and the hydroxyl group, and between the hydroxyl group and the amino group of the aminophenol can be effectively inhibited, the side reaction is well inhibited, and the purity of the product is improved.
Preferably, the adjuvant comprises any one of hydrochloric acid, sulfuric acid, nitric acid, acetic acid or formic acid or a combination of at least two of them, where a typical but non-limiting combination is: a combination of hydrochloric acid and sulfuric acid, a combination of hydrochloric acid and nitric acid, a combination of hydrochloric acid and acetic acid, a combination of sulfuric acid and nitric acid, a combination of sulfuric acid and acetic acid, and a combination of nitric acid and acetic acid.
In the invention, the acid is preferably used as an auxiliary agent, and can better generate ammonium salt with aminophenol generated by reaction, thereby achieving the purpose of inhibiting side reaction.
Preferably, the solvent comprises an organic solvent.
The organic solvent is selected to be beneficial to the dissolution of the nitrophenol, so that the contact and reaction of the auxiliary agent and the catalyst with the nitrophenol in the reaction process are improved.
Preferably, the solvent comprises any one of methanol, ethanol, isopropanol, n-butanol, tetrahydrofuran or dimethylsulfoxide, or a combination of at least two thereof, with typical but non-limiting combinations being: a combination of methanol and ethanol, a combination of methanol and isopropanol, a combination of methanol and n-butanol, a combination of ethanol and isopropanol, a combination of ethanol and n-butanol, a combination of isopropanol and tetrahydrofuran, a combination of n-butanol and dimethyl sulfoxide.
Preferably, the catalyst comprises a noble metal supported catalyst.
Preferably, the noble metal in the noble metal supported catalyst comprises any one of platinum, palladium, nickel or rhodium or a combination of at least two of them, with typical but non-limiting combinations being: a combination of platinum and palladium, a combination of platinum and nickel, a combination of platinum and rhodium, a combination of palladium and nickel, a combination of palladium and rhodium, a combination of nickel and rhodium.
Preferably, the support in the noble metal supported catalyst comprises any one of activated carbon, silica or alumina, or a combination of at least two of them, with typical but non-limiting combinations being: a combination of activated carbon and silica, a combination of activated carbon and alumina, and a combination of silica and alumina.
Preferably, the mass ratio of the nitrophenol to the solvent is 0.01 to 5:1, and may be, for example, 0.01:1, 0.05:1, 0.1:1, 0.12:1, 0.15:1, 0.5:1, 1:1, 1.2:1, 1.5:1, 1.8:1, 2:1, 2.2:1, 2.5:1, 2.8:1, 3:1, 3.5:1, 4:1, 4.5:1 or 5: 1.
Preferably, the molar ratio of the auxiliary agent to nitrophenol is 0.01 to 2:1, for example 0.01:1, 0.02:1, 0.05:1, 0.08:1, 0.1:1, 0.12:1, 0.15:1, 0.18:1, 0.2:1, 0.5:1, 0.8:1, 1:1, 1.2:1, 1.25:1, 1.28:1, 1.3:1, 1.4:1, 1.5:1, 1.8:1 or 2:1, preferably 0.1 to 1: 1.
According to the invention, the molar ratio of the auxiliary agent to the nitrophenol is preferably 0.01-2: 1, so that the effect of inhibiting side reaction can be achieved, the generation of subsequent waste liquid containing the auxiliary agent can be effectively reduced, the addition amount of subsequent alkaline substances of a precipitating agent is reduced, and the cost is saved.
Preferably, the mass ratio of the catalyst to the nitrophenol is 0.01 to 0.5:1, for example, 0.01:1, 0.05:1, 0.1:1, 0.15:1, 0.2:1, 0.25:1, 0.3:1, 0.35:1, 0.4:1, 0.45:1 or 5:1, preferably 0.1 to 0.4: 1.
Preferably, the hydrogenation reaction temperature is 30 ~ 100 ℃, for example can be 30 ℃, 35 ℃, 40 ℃, 45 ℃, 50 ℃, 55 ℃, 60 ℃, 65 ℃, 70 ℃, 75 ℃, 80 ℃, 85 ℃, 90 ℃, 95 ℃ or 100 ℃, preferably 30 ~ 55 ℃.
Preferably, the pressure of the hydrogenation reaction is 0.1 to 10MPa, and may be, for example, 0.1MPa, 0.5MPa, 1MPa, 1.5MPa, 2MPa, 2.5MPa, 3MPa, 3.5MPa, 4MPa, 4.5MPa, 5MPa, 6MPa, 7MPa, 7.5MPa, 8MPa, 8.5MPa, 9MPa or 10 MPa.
Preferably, the time of the hydrogenation reaction is 0.5 to 10 hours, and for example, may be 0.5 hour, 1 hour, 1.5 hour, 2 hours, 2.5 hours, 3 hours, 3.5 hours, 4 hours, 4.5 hours, 5 hours, 5.5 hours, 6 hours, 6.5 hours, 7 hours, 7.5 hours, 8 hours, 8.5 hours, 9 hours, 9.5 hours or 10 hours, preferably 2 to 8 hours.
Preferably, the nitrophenol comprises a substituted or unsubstituted nitrophenol.
Preferably, the substituent is a halogen atom, which may be, for example, any one or a combination of at least two of fluorine, chlorine, bromine or iodine, with typical but non-limiting combinations being: a combination of fluorine and chlorine, a combination of fluorine and bromine, a combination of fluorine and iodine, and a combination of chlorine and bromine.
Preferably, the nitrophenol is 2, 6-dichloro-4-nitrophenol.
The nitrophenol in the invention is preferably 2, 6-dichloro-4-nitrophenol, because 2, 6-dichloro-4-aminophenol is an important intermediate of the pesticide chlorfluazuron, but the process for producing the intermediate in the field of pesticide production mainly adopts methods such as sodium hydrosulfite or hydrazine hydrate, and the like, and a process for directly synthesizing the 2, 6-dichloro-4-nitrophenol and hydrogen does not exist.
Preferably, the method comprises the steps of:
(1) and (3) carrying out hydrogenation reaction on the nitrophenol and hydrogen under the action of a solvent, an auxiliary agent and a catalyst to generate aminophenol, and separating the aminophenol from the catalyst to obtain a reaction solution.
(2) And carrying out liquid phase separation on the reaction liquid to obtain concentrated reaction liquid and a recovered solvent.
(3) And adding a precipitating agent into the concentrated reaction solution, and carrying out solid-liquid separation and drying to obtain the aminophenol.
The method for synthesizing the aminophenol further comprises the steps of recovering the solvent and obtaining the aminophenol through crystallization of the precipitating agent after synthesis, and the two steps not only can recover the solvent added in the hydrogenation reaction and realize the recycling of the solvent, but also can further obtain a high-purity aminophenol product.
The solid-liquid separation is not limited in the present invention, and any operation known to those skilled in the art that can be used for solid-liquid separation may be used, and examples thereof include filtration, sedimentation, or centrifugation.
The present invention is not limited to drying, and any procedure known to those skilled in the art that can be used to dry a crystal sample may be used, and for example, vacuum drying or forced air drying may be used.
Preferably, the reaction in step (1) is carried out in a reaction kettle.
Preferably, the separated catalyst is mechanically used in the hydrogenation reaction.
Preferably, the liquid phase separation means in step (2) comprises distillation.
Preferably, the distillation is a negative pressure distillation.
Preferably, the absolute pressure of the negative pressure distillation is 5 to 20kPa, for example, 5kPa, 6kPa, 7kPa, 8kPa, 9kPa, 10kPa, 11kPa, 12kPa, 13kPa, 14kPa, 15kPa, 16kPa, 17kPa, 18kPa, 19kPa, or 20kPa, preferably 8 to 15 kPa.
Preferably, the mass concentration of aminophenol in the concentrated reaction solution is 15 to 90%, and may be, for example, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, or 90%, preferably 30 to 75%.
Preferably, the recovered solvent is recycled to the hydrogenation reaction of step (1).
Preferably, step (3) further comprises, before adding the precipitating agent: water was added to the concentrated reaction solution.
Preferably, the water is added dropwise.
According to the invention, water is dripped into the concentrated reaction liquid to realize the transfer of aminophenol in the concentrated reaction liquid, the dripping is uniform speed dripping, heat is released in the process of dripping water, the water content in the concentrated reaction liquid at the bottom is gradually increased, products are gradually separated out, the impurity entrainment is reduced, and the purity of aminophenol is favorably improved.
Preferably, the temperature of the concentrated reaction solution is controlled to be-10-70 ℃ in the dropping process, for example, the temperature can be-10 ℃, -5 ℃, -2 ℃, 0 ℃, 2 ℃,5 ℃, 10 ℃, 20 ℃, 30 ℃, 40 ℃, 50 ℃, 60 ℃ or 70 ℃, preferably 0-30 ℃.
The invention controls the temperature of the concentrated reaction solution by dripping water with certain temperature into the concentrated reaction solution, thereby better controlling the solubility of aminophenol in the water phase and improving the yield of the product.
Preferably, the total time of the dropwise addition is 0.1-1 h, and can be 0.1h, 0.2h, 0.3h, 0.4h, 0.5h, 0.6h, 0.7h, 0.8h, 0.9h or 1h, for example.
Preferably, the mass ratio of the concentrated reaction solution to water is 0.1 to 10:1, and may be, for example, 0.1:1, 0.5:1, 0.8:1, 1:1, 1.5:1, 2:1, 2.5:1, 3:1, 3.5:1, 4:1, 4.5:1, 5:1, 5.5:1, 6:1, 6.5:1, 7:1, 7.5:1, 8:1, 8.5:1, 9:1, 9.5:1, or 10:1, preferably 1 to 8: 1.
Preferably, the precipitation agent comprises an alkaline substance.
The precipitating agent comprises an alkaline substance, and can neutralize an acid auxiliary agent added in a reaction system, so that ammonium salt is converted into aminophenol to be precipitated from a water phase, and an aminophenol product is obtained.
Preferably, the alkaline substance comprises an inorganic base or a weak acid salt of a strong base, preferably any one or a combination of at least two of sodium hydroxide, potassium hydroxide, ammonia, sodium carbonate, potassium carbonate, sodium bicarbonate or calcium hydroxide, wherein a typical but non-limiting combination is: a combination of sodium hydroxide and potassium hydroxide, a combination of sodium hydroxide and aqueous ammonia, a combination of potassium hydroxide and sodium carbonate, a combination of aqueous ammonia and sodium carbonate, a combination of sodium carbonate and sodium bicarbonate, a combination of sodium bicarbonate and calcium hydroxide.
Preferably, the pH of the concentrated reaction solution after adding the precipitating agent is 5 to 7, and may be, for example, 5, 5.2, 5.3, 5.5, 5.8, 5.9, 6.0, 6.2, 6.5, 6.8, or 7.0.
In the process of separating out the aminophenol, the pH value of the concentrated reaction solution is preferably controlled in a neutral environment of 5-7, because the separation of the aminophenol is facilitated only in the neutral environment, and the yield and the purity of the product are improved.
As a preferred technical scheme of the invention, the method comprises the following steps:
(1) in a reaction kettle, carrying out hydrogenation reaction on nitrophenol and hydrogen under the action of a solvent, an auxiliary agent and a catalyst to generate aminophenol, separating the aminophenol from the catalyst to obtain a reaction solution, and mechanically applying the separated catalyst to the hydrogenation reaction; wherein the mass ratio of the nitrophenol to the solvent is 0.01-5: 1, the molar ratio of the auxiliary agent to the nitrophenol is 0.01-2: 1, the mass ratio of the catalyst to the nitrophenol is 0.01-0.5: 1, the temperature of the hydrogenation reaction is 30-100 ℃, the pressure is 0.1-10 MPa, and the time is 0.5-10 h;
(2) carrying out negative pressure distillation separation on the reaction liquid under the absolute pressure of 5-20 kPa to obtain a concentrated reaction liquid and a recovered solvent, wherein the mass concentration of aminophenol in the concentrated reaction liquid is 15-90%, and the recovered solvent is applied to the hydrogenation reaction in the step (1) in a sleeving manner;
(3) dropwise adding water into the concentrated reaction liquid, wherein the total dropwise adding time is 0.1-1 h, the mass ratio of the concentrated reaction liquid to the water is 0.1-10: 1, and the temperature of the concentrated reaction liquid is controlled to be-10-70 ℃ in the dropwise adding process; and then adding an alkaline substance to adjust the pH value of the concentrated reaction solution to 5-7, and drying a filter cake obtained by solid-liquid separation to obtain the aminophenol.
Compared with the prior art, the invention has at least the following beneficial effects:
(1) the synthesis method of the aminophenol provided by the invention takes nitrophenol as a raw material, the conversion rate is controlled by adding an auxiliary agent, the side reaction is less, the yield of the aminophenol reaches more than 80 wt%, the maximum yield of the aminophenol reaches more than 96 wt%, the purity of the aminophenol is more than 98.5 wt%, and the optimal yield of the aminophenol reaches more than 99.5 wt%;
(2) the synthesis method of the aminophenol provided by the invention adopts hydrogen as a reducing agent, has no pollution problem generated during reduction of substances such as hydrazine hydrate, sodium hydrosulfite and the like, and also has no toxicity problem involved during reduction of hydrazine hydrate, and has the advantages of green and high-efficiency process, cleanness, environmental protection and strong economic competitiveness;
(3) the synthesis method of aminophenol provided by the invention has the advantages of simple post-treatment process, less side reaction, recyclable solvent and small difficulty in treating three wastes.
Drawings
FIG. 1 is a schematic flow diagram of a process for synthesizing an aminophenol according to the present invention.
Detailed Description
The technical scheme of the invention is further explained by the specific implementation mode in combination with the attached drawings.
The present invention is described in further detail below. The following examples are merely illustrative of the present invention and do not represent or limit the scope of the claims, which are defined by the claims.
The synthetic route of the aminophenol provided by the invention is shown in figure 1, and the method specifically comprises the following steps:
(1) in a reaction kettle, carrying out hydrogenation reaction on nitrophenol and hydrogen under the action of a solvent, an auxiliary agent and a catalyst to generate aminophenol, separating the aminophenol from the catalyst to obtain a reaction solution, and mechanically applying the separated catalyst to the hydrogenation reaction;
(2) concentrating and separating the reaction liquid through negative pressure distillation to obtain a concentrated reaction liquid and a recovered solvent, wherein the mass concentration of aminophenol in the concentrated reaction liquid is 15-90%, and the recovered solvent is applied to the hydrogenation reaction in the step (1);
(3) dropwise adding water into the concentrated reaction liquid, wherein the mass ratio of the concentrated reaction liquid to the water is 0.1-10: 1, and the temperature of the concentrated reaction liquid is controlled to be-10-70 ℃ in the dropwise adding process; and then adding an alkaline substance to adjust the pH value of the concentrated reaction solution to 5-7 for crystallization, and drying a filter cake obtained by solid-liquid separation of the mixed solution to obtain the aminophenol.
First, an embodiment
Example 1
This example provides a method for synthesizing 2, 6-dichloro-4-aminophenol, including the following steps:
(1) putting 2, 6-dichloro-4-nitrophenol and tetrahydrofuran into a high-pressure reaction kettle, wherein the mass ratio of the 2, 6-dichloro-4-nitrophenol to the tetrahydrofuran is 0.01:1, and Rh/Al is added2O3A load type catalyst and an auxiliary agent acetic acid, wherein the mass ratio of the catalyst to 2, 6-dichloro-4-nitrophenol is 0.01:1, and the molar ratio of the auxiliary agent acetic acid to 2, 6-dichloro-4-nitrophenol is 2: 1; carrying out hydrogenation reaction at the reaction temperature of 30 ℃ and the pressure of 0.2MPa for 10h, cooling and relieving pressure after the reaction is finished, separating reaction liquid from a catalyst, and returning the catalyst to the hydrogenation reaction for reuse;
(2) carrying out negative pressure distillation on the separated reaction liquid under the absolute pressure of 20kPa to remove tetrahydrofuran, finishing when the mass concentration of 2, 6-dichloro-4-aminophenol in the concentrated reaction liquid is 15%, and returning the removed tetrahydrofuran to the hydrogenation reaction in the step (1) for reuse;
(3) dropwise adding deionized water into the concentrated reaction solution at a constant speed for crystallization, wherein the total dropwise adding time is 0.1h, the mass ratio of the concentrated reaction solution to the deionized water is 0.1:1, the temperature of the concentrated reaction solution is controlled to be-10 ℃, and 2, 6-dichloro-4-aminophenol is separated out in the dropwise adding process; after the dropwise addition, adding sodium hydroxide to adjust the pH value in the concentrated reaction solution to 5, carrying out centrifugal separation on the mixed solution, and drying the solid to constant weight to obtain a finished product of the 2, 6-dichloro-4-aminophenol.
Example 2
This example provides a method for synthesizing 2, 6-dichloro-4-aminophenol, including the following steps:
(1) putting 2, 6-dichloro-4-nitrophenol and ethanol into a high-pressure reaction kettle, wherein the mass ratio of the 2, 6-dichloro-4-nitrophenol to the ethanol is 0.8:1, a raney nickel catalyst and an auxiliary agent sulfuric acid are added, the mass ratio of the raney nickel catalyst to the 2, 6-dichloro-4-nitrophenol is 0.1:1, and the molar ratio of the auxiliary agent sulfuric acid to the 2, 6-dichloro-4-nitrophenol is 0.01: 1; carrying out hydrogenation reaction at the reaction temperature of 40 ℃ and the pressure of 0.5MPa for 5h, cooling and relieving pressure after the reaction is finished, separating reaction liquid from a catalyst, and returning the catalyst to the hydrogenation reaction for reuse;
(2) carrying out negative pressure distillation on the separated reaction liquid under the absolute pressure of 18kPa to remove ethanol until the mass concentration of the 2, 6-dichloro-4-aminophenol in the concentrated reaction liquid is 50%, and returning the removed ethanol to the hydrogenation reaction in the step (1) for reuse;
(3) dropwise adding deionized water into the concentrated reaction solution at a constant speed for crystallization, wherein the total dropwise adding time is 1h, the mass ratio of the concentrated reaction solution to the deionized water is 3:1, the temperature of the concentrated reaction solution is controlled to be 10 ℃, and 2, 6-dichloro-4-aminophenol is separated out in the dropwise adding process; and after the dropwise addition is finished, adding sodium carbonate to adjust the pH value in the concentrated reaction solution to 5.8, filtering the mixed solution, and drying the solid to constant weight to obtain a finished product of the 2, 6-dichloro-4-aminophenol.
Example 3
This example provides a method for synthesizing 2, 6-dichloro-4-aminophenol, including the following steps:
(1) putting 2, 6-dichloro-4-nitrophenol and methanol into a high-pressure reaction kettle, wherein the mass ratio of the 2, 6-dichloro-4-nitrophenol to the methanol is 0.3:1, the Pd/C supported catalyst and auxiliary agent hydrochloric acid are added, the mass ratio of the catalyst to the 2, 6-dichloro-4-nitrophenol is 0.05:1, and the molar ratio of the auxiliary agent hydrochloric acid to the 2, 6-dichloro-4-nitrophenol is 0.1: 1; carrying out hydrogenation reaction at the reaction temperature of 50 ℃ and the pressure of 1MPa for 2h, cooling and relieving pressure after the reaction is finished, separating reaction liquid from a catalyst, and returning the catalyst to the hydrogenation reaction for reuse;
(2) carrying out negative pressure distillation on the separated reaction liquid under the absolute pressure of 5kPa to remove methanol until the mass concentration of 2, 6-dichloro-4-aminophenol in the concentrated reaction liquid is 30%, and returning the removed methanol to the hydrogenation reaction in the step (1) for reuse;
(3) dropwise adding deionized water into the concentrated reaction solution at a constant speed for crystallization, wherein the total dropwise adding time is 0.7h, the mass ratio of the concentrated reaction solution to the deionized water is 0.9:1, the temperature of the concentrated reaction solution is controlled to be 20 ℃, and 2, 6-dichloro-4-aminophenol is separated out in the dropwise adding process; after the dropwise addition, adding sodium hydroxide to adjust the pH value in the concentrated reaction solution to 6.1, filtering the mixed solution, and drying the solid to constant weight to obtain a finished product of the 2, 6-dichloro-4-aminophenol.
Example 4
This example provides a method for synthesizing 2, 6-dichloro-4-aminophenol, including the following steps:
(1) putting 2, 6-dichloro-4-nitrophenol and methanol into a high-pressure reaction kettle, wherein the mass ratio of the 2, 6-dichloro-4-nitrophenol to the methanol is 5:1, and Pt/SiO2The catalyst comprises a supported catalyst and an auxiliary agent nitric acid, wherein the mass ratio of the catalyst to 2, 6-dichloro-4-nitrophenol is 0.5:1, and the molar ratio of the auxiliary agent nitric acid to 2, 6-dichloro-4-nitrophenol is 1.5: 1; carrying out hydrogenation reaction at the reaction temperature of 100 ℃ and the pressure of 7MPa for 4h, cooling and relieving pressure after the reaction is finished, separating reaction liquid from a catalyst, and returning the catalyst to the hydrogenation reaction for reuse;
(2) carrying out negative pressure distillation on the separated reaction liquid under the absolute pressure of 15kPa to remove methanol until the mass concentration of the 2, 6-dichloro-4-aminophenol in the concentrated reaction liquid is 90%, and returning the removed methanol to the hydrogenation reaction in the step (1) for reuse;
(3) dropwise adding deionized water into the concentrated reaction solution at a constant speed for crystallization, wherein the total dropwise adding time is 0.2h, the mass ratio of the concentrated reaction solution to the deionized water is 10:1, the temperature of the concentrated reaction solution is controlled to be 70 ℃, and 2, 6-dichloro-4-aminophenol is separated out in the dropwise adding process; after the dropwise addition, potassium hydroxide is added to adjust the pH value in the concentrated reaction solution to 6.8, the mixed solution is filtered, and the solid is dried to constant weight to obtain a finished product of the 2, 6-dichloro-4-aminophenol.
Example 5
This example provides a method for synthesizing 2, 6-dichloro-4-aminophenol, including the following steps:
(1) putting 2, 6-dichloro-4-nitrophenol and dimethyl sulfoxide into a high-pressure reaction kettle, wherein the mass ratio of the 2, 6-dichloro-4-nitrophenol to the dimethyl sulfoxide is 3.5:1, a Pt/C supported catalyst and an auxiliary agent hydrochloric acid are added, the mass ratio of the catalyst to the 2, 6-dichloro-4-nitrophenol is 0.3:1, and the molar ratio of the auxiliary agent hydrochloric acid to the 2, 6-dichloro-4-nitrophenol is 0.6: 1; carrying out hydrogenation reaction at the reaction temperature of 60 ℃ and the pressure of 10MPa for 8h, cooling and relieving pressure after the reaction is finished, separating reaction liquid from a catalyst, and returning the catalyst to the hydrogenation reaction for reuse;
(2) carrying out negative pressure distillation on the separated reaction liquid under the absolute pressure of 13kPa to remove dimethyl sulfoxide till the mass concentration of 2, 6-dichloro-4-aminophenol in the concentrated reaction liquid is 80%, and returning the removed dimethyl sulfoxide to the hydrogenation reaction in the step (1) for reuse;
(3) dropwise adding deionized water into the concentrated reaction solution at a constant speed for crystallization, wherein the total dropwise adding time is 0.3h, the mass ratio of the concentrated reaction solution to the deionized water is 8:1, the temperature of the concentrated reaction solution is controlled to be 30 ℃, and 2, 6-dichloro-4-aminophenol is separated out in the dropwise adding process; and after the dropwise addition, adding calcium hydroxide to adjust the pH value in the concentrated reaction solution to 7, filtering the mixed solution, and drying the solid to constant weight to obtain a finished product of the 2, 6-dichloro-4-aminophenol.
Example 6
This example provides a method for synthesizing 2, 6-dichloro-4-aminophenol, including the following steps:
(1) putting 2, 6-dichloro-4-nitrophenol and isopropanol into a high-pressure reaction kettle, wherein the mass ratio of the 2, 6-dichloro-4-nitrophenol to the isopropanol is 2.5:1, and Pd/Al is2O3The catalyst comprises a supported catalyst and an auxiliary agent sulfuric acid, wherein the mass ratio of the catalyst to 2, 6-dichloro-4-nitrophenol is 0.4:1, and the molar ratio of the auxiliary agent sulfuric acid to 2, 6-dichloro-4-nitrophenol is 0.3: 1; carrying out hydrogenation reaction at the reaction temperature of 80 ℃ and the pressure of 3MPa for 6h, cooling and relieving pressure after the reaction is finished, separating reaction liquid from a catalyst, and returning the catalyst to the hydrogenation reaction for reuse;
(2) carrying out negative pressure distillation on the separated reaction liquid under the absolute pressure of 10kPa to remove isopropanol until the mass concentration of the 2, 6-dichloro-4-aminophenol in the concentrated reaction liquid is 75%, and returning the removed isopropanol to the hydrogenation reaction in the step (1) for reuse;
(3) dropwise adding deionized water into the concentrated reaction solution at a constant speed for crystallization, wherein the total dropwise adding time is 0.3h, the mass ratio of the concentrated reaction solution to the deionized water is 5:1, the temperature of the concentrated reaction solution is controlled to be 50 ℃, and 2, 6-dichloro-4-aminophenol is separated out in the dropwise adding process; and after dropwise adding, adding ammonia water to adjust the pH value of the concentrated reaction solution to 6.5, performing centrifugal separation on the mixed solution, and drying the solid to constant weight to obtain a finished product of the 2, 6-dichloro-4-aminophenol.
Example 7
This example provides a method for synthesizing 2, 6-dichloro-4-aminophenol, including the following steps:
(1) putting 2, 6-dichloro-4-nitrophenol and n-butanol into a high-pressure reaction kettle, wherein the mass ratio of the 2, 6-dichloro-4-nitrophenol to the n-butanol is 1.5:1, and a Pt/C supported catalyst and an auxiliary agent formic acid are added, wherein the mass ratio of the catalyst to the 2, 6-dichloro-4-nitrophenol is 0.2:1, and the molar ratio of the auxiliary agent formic acid to the 2, 6-dichloro-4-nitrophenol is 1: 1; carrying out hydrogenation reaction at the reaction temperature of 70 ℃ and the pressure of 5MPa for 0.5h, cooling and relieving pressure after the reaction is finished, separating reaction liquid from a catalyst, and returning the catalyst to the hydrogenation reaction for reuse;
(2) carrying out negative pressure distillation on the separated reaction liquid under the absolute pressure of 8kPa to remove n-butyl alcohol until the mass concentration of the 2, 6-dichloro-4-aminophenol in the concentrated reaction liquid is 60%, and returning the removed n-butyl alcohol to the hydrogenation reaction in the step (1) for reuse;
(3) dropwise adding deionized water into the concentrated reaction solution at a constant speed for crystallization, wherein the total dropwise adding time is 0.8h, the mass ratio of the concentrated reaction solution to the deionized water is 2:1, the temperature of the concentrated reaction solution is controlled to be 40 ℃, and 2, 6-dichloro-4-aminophenol is separated out in the dropwise adding process; and adding potassium carbonate to adjust the pH value of the concentrated reaction solution to 5.5 after dropwise adding, filtering the mixed solution, and drying the solid to constant weight to obtain a finished product of the 2, 6-dichloro-4-aminophenol.
Example 8
This example provides a method for synthesizing 2, 6-dichloro-4-aminophenol, which is the same as in example 3 except that "the molar ratio of the auxiliary hydrochloric acid to the 2, 6-dichloro-4-nitrophenol is 0.1: 1" in step (1) is replaced with "the molar ratio of the auxiliary hydrochloric acid to the 2, 6-dichloro-4-nitrophenol is 1: 1".
Example 9
This example provides a method for synthesizing 2, 6-dichloro-4-aminophenol, which is the same as in example 3 except that "the molar ratio of the auxiliary hydrochloric acid to 2, 6-dichloro-4-nitrophenol is 0.1: 1" in step (1) is replaced with "the molar ratio of the auxiliary hydrochloric acid to 2, 6-dichloro-4-nitrophenol is 0.01: 1".
Example 10
This example provides a method for synthesizing 2, 6-dichloro-4-aminophenol, which is the same as in example 3 except that "the molar ratio of the auxiliary hydrochloric acid to 2, 6-dichloro-4-nitrophenol is 0.1: 1" in step (1) is replaced with "the molar ratio of the auxiliary hydrochloric acid to 2, 6-dichloro-4-nitrophenol is 2: 1".
Example 11
This example provides a method for synthesizing 2, 6-dichloro-4-aminophenol, which is the same as that of example 3, except that the auxiliary hydrochloric acid in step (1) is replaced with the auxiliary sodium chloride.
Example 12
This example provides a method for synthesizing p-aminophenol, which is the same as that of example 3 except that "2, 6-dichloro-4-nitrophenol" in step (1) is replaced with "p-nitrophenol", and correspondingly, "2, 6-dichloro-4-aminophenol" in step (2) and step (3) is replaced with "p-aminophenol".
Example 13
This example provides a process for the synthesis of 2, 6-dichloro-4-aminophenol by repeating the process of example 3 for 10 batches using the catalyst recovered in example 3, and the same procedure as in example 3 except that 3% of the total weight of the first batch of catalyst of example 3 was added to the reaction of set 1.
Second, test and results
The test method comprises the following steps: the (2, 6-dichloro-4-) aminophenol products of examples 1 to 13 were collected, subjected to quantitative analysis by gas chromatography, the purity of the (2, 6-dichloro-4-) aminophenol product was measured, and the product yield was calculated from the (2, 6-dichloro-4-) nitrophenol.
The product yields and product purities of examples 1 to 12 are shown in Table 1.
The product yields and product purities of the set-up experiments of example 13 are shown in table 2.
TABLE 1
From table 1, the following points can be seen:
(1) it can be seen from the comprehensive examples 1 to 12 that in the examples 1 to 12, nitrophenol is directly reacted with hydrogen under the action of an auxiliary agent, a solvent and a catalyst, the yield of aminophenol is over 80 wt% and the purity is over 98.5 wt% under different conditions, the problems of poor selectivity and large amount of three wastes of common reducing agents such as hydrazine hydrate and sodium hydrosulfite in the prior art are solved, and the industrial application value is high;
(2) it can be seen from the combination of examples 3 and 8 to 10 that the molar ratios of hydrochloric acid to nitrophenol in examples 3 and 8 are 0.1:1 and 1:1, respectively, and the yields of 2, 6-dichloro-4-aminophenol in examples 3 and 8 are 96.1 wt% and 95.2 wt%, respectively, compared with the molar ratios of hydrochloric acid to nitrophenol in examples 9 and 10 of 0.01:1 and 2:1, respectively, while the yields of 2, 6-dichloro-4-aminophenol in examples 9 and 10 were only 94.33 wt% and 94.01 wt%, respectively, the purity is lower than that of the embodiment 3 and the embodiment 8, so that the invention can better improve the yield and the purity of the 2, 6-dichloro-4-aminophenol by controlling the molar ratio of the hydrochloric acid to the nitrophenol within the range of 0.1-1: 1;
(3) by combining example 3 with example 11, example 3 has 96.1 wt% of yield and 99.67 wt% of purity of 2, 6-dichloro-4-aminophenol in example 3, and only 86.11 wt% of yield and only 99.02 wt% of purity of 2, 6-dichloro-4-aminophenol in example 11, compared to example 11 which uses sodium chloride as an auxiliary, it is shown that hydrochloric acid is preferred as an auxiliary in the present invention, which can better inhibit the polymerization reaction between amino groups of aminophenol itself and amino groups, hydroxyl groups and hydroxyl groups, and hydroxyl groups and amino groups, and improve the yield and purity of products.
TABLE 2
As can be seen from Table 2, the catalyst of the invention has high recovery rate, the yield of 2, 6-dichloro-4-aminophenol is more than 95 wt% after being used for 10 times, the purity is more than 99.5 wt%, and the catalyst has high industrial application value.
In conclusion, the synthesis method of the aminophenol provided by the invention can directly realize the reaction of the nitrophenol and the hydrogen by adopting an auxiliary agent and solvent phase auxiliary mode, does not need to add reducing agents such as hydrazine hydrate, sodium hydrosulfite and the like, has high selectivity, does not have a large amount of three wastes, can be suitable for preparing substituted or unsubstituted aminophenol products, can recycle the catalyst, and can obtain the nitrophenol with the yield of more than 80 wt% and the purity of more than 98.5 wt%, the yield of more than 96 wt% and the purity of more than 99.5 wt% under better conditions, thereby having higher industrial application value.
The applicant declares that the present invention illustrates the detailed structural features of the present invention through the above embodiments, but the present invention is not limited to the above detailed structural features, that is, it does not mean that the present invention must be implemented depending on the above detailed structural features. It should be understood by those skilled in the art that any modifications of the present invention, equivalent substitutions of selected components of the present invention, additions of auxiliary components, selection of specific modes, etc., are within the scope and disclosure of the present invention.
Claims (10)
1. A method for synthesizing aminophenol, comprising: the nitrophenol and hydrogen are subjected to hydrogenation reaction under the action of a solvent, an auxiliary agent and a catalyst to generate the aminophenol.
2. The method according to claim 1, wherein the auxiliary in the method is an acid auxiliary;
preferably, the auxiliary agent comprises any one or a combination of at least two of hydrochloric acid, sulfuric acid, nitric acid, acetic acid or formic acid;
preferably, the solvent comprises an organic solvent;
preferably, the solvent comprises any one of methanol, ethanol, isopropanol, n-butanol, tetrahydrofuran or dimethyl sulfoxide or a combination of at least two of the same;
preferably, the catalyst comprises a noble metal supported catalyst;
preferably, the noble metal in the noble metal supported catalyst comprises any one or a combination of at least two of platinum, palladium, nickel or rhodium;
preferably, the support in the noble metal supported catalyst comprises any one of activated carbon, silica or alumina or a combination of at least two thereof.
3. The method according to claim 1 or 2, wherein the mass ratio of the nitrophenol to the solvent is 0.01-5: 1;
preferably, the molar ratio of the auxiliary agent to the nitrophenol is 0.01-2: 1, preferably 0.1-1: 1;
preferably, the mass ratio of the catalyst to the nitrophenol is 0.01-0.5: 1, and preferably 0.1-0.4: 1.
4. The process according to any one of claims 1 to 3, wherein the temperature of the hydrogenation reaction is 30 to 100 ℃, preferably 30 to 55 ℃;
preferably, the pressure of the hydrogenation reaction is 0.1-10 MPa;
preferably, the time of the hydrogenation reaction is 0.5-10 h, preferably 2-8 h.
5. The method of any one of claims 1 to 4, wherein the nitrophenol comprises a substituted or unsubstituted nitrophenol;
preferably, the substituent is a halogen atom;
preferably, the nitrophenol is 2, 6-dichloro-4-nitrophenol.
6. A method according to any one of claims 1 to 5, characterized in that the method comprises the steps of:
(1) the nitrophenol and hydrogen are subjected to hydrogenation reaction under the action of a solvent, an auxiliary agent and a catalyst to generate aminophenol, and the aminophenol is separated from the catalyst to obtain a reaction solution;
(2) carrying out liquid phase separation on the reaction solution to obtain a concentrated reaction solution and a recovered solvent;
(3) and adding a precipitating agent into the concentrated reaction solution, and carrying out solid-liquid separation and drying to obtain the aminophenol.
7. The method of claim 6, wherein the reaction in step (1) is carried out in a reaction kettle;
preferably, the separated catalyst is mechanically used in the hydrogenation reaction.
8. The process of claim 6 or 7, wherein the liquid phase separation means in step (2) comprises distillation;
preferably, the distillation is a negative pressure distillation;
preferably, the absolute pressure of the negative pressure distillation is 5-20 kPa, and preferably 8-15 kPa;
preferably, the mass concentration of aminophenol in the concentrated reaction liquid is 15-90%, preferably 30-75%;
preferably, the recovered solvent is recycled to the hydrogenation reaction of step (1).
9. The method according to any one of claims 6 to 8, wherein the step (3) further comprises, before adding the precipitating agent: adding water to the concentrated reaction solution;
preferably, the water is added dropwise;
preferably, the temperature of the concentrated reaction solution is controlled to be-10-70 ℃ in the dropwise adding process, and preferably 0-30 ℃;
preferably, the total dropping time is 0.1-1 h;
preferably, the mass ratio of the concentrated reaction liquid to water is 0.1-10: 1, preferably 1-8: 1;
preferably, the precipitation agent comprises an alkaline substance;
preferably, the alkaline substance comprises an inorganic base or a strong base weak acid salt, preferably any one or a combination of at least two of sodium hydroxide, potassium hydroxide, ammonia water, sodium carbonate, potassium carbonate, sodium bicarbonate or calcium hydroxide;
preferably, the pH of the concentrated reaction solution after the precipitating agent is added is 5-7.
10. A method according to any one of claims 1 to 9, characterized in that the method comprises the steps of:
(1) in a reaction kettle, carrying out hydrogenation reaction on nitrophenol and hydrogen under the action of a solvent, an auxiliary agent and a catalyst to generate aminophenol, separating the aminophenol from the catalyst to obtain a reaction solution, and mechanically applying the separated catalyst to the hydrogenation reaction; wherein the mass ratio of the nitrophenol to the solvent is 0.01-5: 1, the molar ratio of the auxiliary agent to the nitrophenol is 0.01-2: 1, the mass ratio of the catalyst to the nitrophenol is 0.01-0.5: 1, the temperature of the hydrogenation reaction is 30-100 ℃, the pressure is 0.1-10 MPa, and the time is 0.5-10 h;
(2) carrying out negative pressure distillation separation on the reaction liquid under the absolute pressure of 5-20 kPa to obtain a concentrated reaction liquid and a recovered solvent, wherein the mass concentration of aminophenol in the concentrated reaction liquid is 15-90%, and the recovered solvent is applied to the hydrogenation reaction in the step (1) in a sleeving manner;
(3) dropwise adding water into the concentrated reaction liquid, wherein the total dropwise adding time is 0.1-1 h, the mass ratio of the concentrated reaction liquid to the water is 0.1-10: 1, and the temperature of the concentrated reaction liquid is controlled to be-10-70 ℃ in the dropwise adding process; and then adding an alkaline substance to adjust the pH value of the concentrated reaction solution to 5-7, and drying a filter cake obtained by solid-liquid separation to obtain the aminophenol.
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| CN112920060A (en) * | 2021-01-28 | 2021-06-08 | 浙江吉泰新材料股份有限公司 | Synthesis device and application of 2, 6-dichloro-4-aminophenol |
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