CN117486765A - Method for preparing 4,4' -dichlorodiphenyl sulfone - Google Patents
Method for preparing 4,4' -dichlorodiphenyl sulfone Download PDFInfo
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- CN117486765A CN117486765A CN202311474073.XA CN202311474073A CN117486765A CN 117486765 A CN117486765 A CN 117486765A CN 202311474073 A CN202311474073 A CN 202311474073A CN 117486765 A CN117486765 A CN 117486765A
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- dichlorodiphenyl sulfone
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- GPAPPPVRLPGFEQ-UHFFFAOYSA-N 4,4'-dichlorodiphenyl sulfone Chemical compound C1=CC(Cl)=CC=C1S(=O)(=O)C1=CC=C(Cl)C=C1 GPAPPPVRLPGFEQ-UHFFFAOYSA-N 0.000 title claims abstract description 37
- 238000000034 method Methods 0.000 title claims abstract description 37
- 238000006243 chemical reaction Methods 0.000 claims abstract description 55
- 239000003054 catalyst Substances 0.000 claims abstract description 48
- MVPPADPHJFYWMZ-UHFFFAOYSA-N chlorobenzene Chemical compound ClC1=CC=CC=C1 MVPPADPHJFYWMZ-UHFFFAOYSA-N 0.000 claims abstract description 28
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims description 40
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims description 40
- YXFVVABEGXRONW-UHFFFAOYSA-N Toluene Chemical compound CC1=CC=CC=C1 YXFVVABEGXRONW-UHFFFAOYSA-N 0.000 claims description 36
- VZGDMQKNWNREIO-UHFFFAOYSA-N tetrachloromethane Chemical compound ClC(Cl)(Cl)Cl VZGDMQKNWNREIO-UHFFFAOYSA-N 0.000 claims description 36
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims description 30
- 238000003756 stirring Methods 0.000 claims description 29
- 239000012295 chemical reaction liquid Substances 0.000 claims description 25
- FYSNRJHAOHDILO-UHFFFAOYSA-N thionyl chloride Chemical compound ClS(Cl)=O FYSNRJHAOHDILO-UHFFFAOYSA-N 0.000 claims description 25
- FWDBOZPQNFPOLF-UHFFFAOYSA-N ethenyl(triethoxy)silane Chemical compound CCO[Si](OCC)(OCC)C=C FWDBOZPQNFPOLF-UHFFFAOYSA-N 0.000 claims description 24
- 239000000741 silica gel Substances 0.000 claims description 24
- 229910002027 silica gel Inorganic materials 0.000 claims description 24
- YMWUJEATGCHHMB-UHFFFAOYSA-N Dichloromethane Chemical compound ClCCl YMWUJEATGCHHMB-UHFFFAOYSA-N 0.000 claims description 22
- 238000001291 vacuum drying Methods 0.000 claims description 22
- 238000005406 washing Methods 0.000 claims description 22
- 238000001914 filtration Methods 0.000 claims description 21
- 239000000203 mixture Substances 0.000 claims description 21
- 239000012065 filter cake Substances 0.000 claims description 19
- QTBSBXVTEAMEQO-UHFFFAOYSA-N Acetic acid Chemical compound CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 claims description 18
- PPBRXRYQALVLMV-UHFFFAOYSA-N Styrene Chemical compound C=CC1=CC=CC=C1 PPBRXRYQALVLMV-UHFFFAOYSA-N 0.000 claims description 16
- 229910052757 nitrogen Inorganic materials 0.000 claims description 15
- CSCPPACGZOOCGX-UHFFFAOYSA-N Acetone Chemical compound CC(C)=O CSCPPACGZOOCGX-UHFFFAOYSA-N 0.000 claims description 14
- 230000008878 coupling Effects 0.000 claims description 13
- 238000010168 coupling process Methods 0.000 claims description 13
- 238000005859 coupling reaction Methods 0.000 claims description 13
- 238000010438 heat treatment Methods 0.000 claims description 13
- 238000004321 preservation Methods 0.000 claims description 12
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 12
- 238000007254 oxidation reaction Methods 0.000 claims description 11
- 239000000047 product Substances 0.000 claims description 11
- 238000001816 cooling Methods 0.000 claims description 10
- OZAIFHULBGXAKX-UHFFFAOYSA-N 2-(2-cyanopropan-2-yldiazenyl)-2-methylpropanenitrile Chemical compound N#CC(C)(C)N=NC(C)(C)C#N OZAIFHULBGXAKX-UHFFFAOYSA-N 0.000 claims description 9
- 229960000583 acetic acid Drugs 0.000 claims description 9
- 239000012362 glacial acetic acid Substances 0.000 claims description 9
- 239000005457 ice water Substances 0.000 claims description 9
- 239000008367 deionised water Substances 0.000 claims description 8
- 229910021641 deionized water Inorganic materials 0.000 claims description 8
- 238000001035 drying Methods 0.000 claims description 8
- 235000019441 ethanol Nutrition 0.000 claims description 8
- 229920000036 polyvinylpyrrolidone Polymers 0.000 claims description 8
- 239000001267 polyvinylpyrrolidone Substances 0.000 claims description 8
- 235000013855 polyvinylpyrrolidone Nutrition 0.000 claims description 8
- 238000002791 soaking Methods 0.000 claims description 8
- 239000000706 filtrate Substances 0.000 claims description 7
- 238000002156 mixing Methods 0.000 claims description 7
- 239000012299 nitrogen atmosphere Substances 0.000 claims description 7
- 238000010992 reflux Methods 0.000 claims description 7
- 229940117389 dichlorobenzene Drugs 0.000 claims description 6
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 claims description 4
- 230000005587 bubbling Effects 0.000 claims description 4
- 238000000605 extraction Methods 0.000 claims description 4
- 238000004519 manufacturing process Methods 0.000 claims description 4
- KJGYFISADIZFEL-UHFFFAOYSA-N 1-chloro-4-(4-chlorophenyl)sulfinylbenzene Chemical compound C1=CC(Cl)=CC=C1S(=O)C1=CC=C(Cl)C=C1 KJGYFISADIZFEL-UHFFFAOYSA-N 0.000 claims description 3
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 3
- 238000000967 suction filtration Methods 0.000 claims description 3
- 230000001133 acceleration Effects 0.000 claims description 2
- 238000004090 dissolution Methods 0.000 claims description 2
- 230000008901 benefit Effects 0.000 abstract description 8
- 239000002994 raw material Substances 0.000 abstract description 7
- 239000002699 waste material Substances 0.000 abstract description 6
- 230000008569 process Effects 0.000 abstract description 5
- 230000009286 beneficial effect Effects 0.000 abstract description 3
- 239000007810 chemical reaction solvent Substances 0.000 abstract description 3
- 238000009776 industrial production Methods 0.000 abstract description 3
- 239000011968 lewis acid catalyst Substances 0.000 abstract description 3
- 238000002360 preparation method Methods 0.000 abstract description 3
- 230000035484 reaction time Effects 0.000 abstract description 2
- 230000009467 reduction Effects 0.000 abstract description 2
- 238000003786 synthesis reaction Methods 0.000 abstract description 2
- 239000012071 phase Substances 0.000 description 12
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 5
- 239000007791 liquid phase Substances 0.000 description 5
- 239000002904 solvent Substances 0.000 description 5
- 238000005863 Friedel-Crafts acylation reaction Methods 0.000 description 4
- 238000004821 distillation Methods 0.000 description 4
- 239000007788 liquid Substances 0.000 description 4
- 150000003462 sulfoxides Chemical class 0.000 description 4
- AKEJUJNQAAGONA-UHFFFAOYSA-N sulfur trioxide Chemical compound O=S(=O)=O AKEJUJNQAAGONA-UHFFFAOYSA-N 0.000 description 4
- RTZKZFJDLAIYFH-UHFFFAOYSA-N Diethyl ether Chemical compound CCOCC RTZKZFJDLAIYFH-UHFFFAOYSA-N 0.000 description 3
- 239000002253 acid Substances 0.000 description 3
- 230000003647 oxidation Effects 0.000 description 3
- MHAJPDPJQMAIIY-UHFFFAOYSA-N Hydrogen peroxide Chemical compound OO MHAJPDPJQMAIIY-UHFFFAOYSA-N 0.000 description 2
- 230000009471 action Effects 0.000 description 2
- 230000004913 activation Effects 0.000 description 2
- 125000003118 aryl group Chemical group 0.000 description 2
- 125000002915 carbonyl group Chemical group [*:2]C([*:1])=O 0.000 description 2
- 230000003197 catalytic effect Effects 0.000 description 2
- 230000018109 developmental process Effects 0.000 description 2
- 229920006351 engineering plastic Polymers 0.000 description 2
- 238000003912 environmental pollution Methods 0.000 description 2
- 238000000926 separation method Methods 0.000 description 2
- 239000000377 silicon dioxide Substances 0.000 description 2
- KEQGZUUPPQEDPF-UHFFFAOYSA-N 1,3-dichloro-5,5-dimethylimidazolidine-2,4-dione Chemical compound CC1(C)N(Cl)C(=O)N(Cl)C1=O KEQGZUUPPQEDPF-UHFFFAOYSA-N 0.000 description 1
- NGNBDVOYPDDBFK-UHFFFAOYSA-N 2-[2,4-di(pentan-2-yl)phenoxy]acetyl chloride Chemical compound CCCC(C)C1=CC=C(OCC(Cl)=O)C(C(C)CCC)=C1 NGNBDVOYPDDBFK-UHFFFAOYSA-N 0.000 description 1
- 239000004695 Polyether sulfone Substances 0.000 description 1
- 229910008051 Si-OH Inorganic materials 0.000 description 1
- 229910006358 Si—OH Inorganic materials 0.000 description 1
- 238000005917 acylation reaction Methods 0.000 description 1
- 150000001491 aromatic compounds Chemical class 0.000 description 1
- 239000012752 auxiliary agent Substances 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- XTHPWXDJESJLNJ-UHFFFAOYSA-N chlorosulfonic acid Substances OS(Cl)(=O)=O XTHPWXDJESJLNJ-UHFFFAOYSA-N 0.000 description 1
- 230000000536 complexating effect Effects 0.000 description 1
- 230000021615 conjugation Effects 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000002425 crystallisation Methods 0.000 description 1
- 230000008025 crystallization Effects 0.000 description 1
- VILAVOFMIJHSJA-UHFFFAOYSA-N dicarbon monoxide Chemical compound [C]=C=O VILAVOFMIJHSJA-UHFFFAOYSA-N 0.000 description 1
- 239000003814 drug Substances 0.000 description 1
- 239000000975 dye Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000007336 electrophilic substitution reaction Methods 0.000 description 1
- 239000012847 fine chemical Substances 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 230000036541 health Effects 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000000269 nucleophilic effect Effects 0.000 description 1
- 238000000643 oven drying Methods 0.000 description 1
- 239000000575 pesticide Substances 0.000 description 1
- 229920002492 poly(sulfone) Polymers 0.000 description 1
- 229920006393 polyether sulfone Polymers 0.000 description 1
- 230000008929 regeneration Effects 0.000 description 1
- 238000011069 regeneration method Methods 0.000 description 1
- 239000011973 solid acid Substances 0.000 description 1
- 238000003860 storage Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 239000002351 wastewater Substances 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C315/00—Preparation of sulfones; Preparation of sulfoxides
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J27/00—Catalysts comprising the elements or compounds of halogens, sulfur, selenium, tellurium, phosphorus or nitrogen; Catalysts comprising carbon compounds
- B01J27/06—Halogens; Compounds thereof
- B01J27/125—Halogens; Compounds thereof with scandium, yttrium, aluminium, gallium, indium or thallium
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J31/00—Catalysts comprising hydrides, coordination complexes or organic compounds
- B01J31/02—Catalysts comprising hydrides, coordination complexes or organic compounds containing organic compounds or metal hydrides
- B01J31/06—Catalysts comprising hydrides, coordination complexes or organic compounds containing organic compounds or metal hydrides containing polymers
- B01J31/069—Hybrid organic-inorganic polymers, e.g. silica derivatized with organic groups
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J2231/00—Catalytic reactions performed with catalysts classified in B01J31/00
- B01J2231/70—Oxidation reactions, e.g. epoxidation, (di)hydroxylation, dehydrogenation and analogues
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P20/00—Technologies relating to chemical industry
- Y02P20/50—Improvements relating to the production of bulk chemicals
- Y02P20/584—Recycling of catalysts
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
The invention discloses a method for preparing 4,4' -dichloro diphenyl sulfone, which belongs to the technical field of organic synthesis, and uses chlorobenzene as a raw material and a reaction solvent, and uses supported AlCl 3 The catalyst can be used as a stable heterogeneous Lewis acid catalyst, and supported AlCl is used 3 The catalyst has the remarkable advantages of mild reaction conditions, high yield, short reaction time, simple working process, low cost, convenient preparation and treatment, repeated use of the catalyst, and reduction of unnecessary risks and wastes generated by a conventional homogeneous system; the invention has simple process, less waste, low cost, multiple circulation of catalyst, high purity of product, content of over 99.9 percent and sulfoxideThe isomer content is lower than 2%, the yield reaches more than 98%, and the economic benefit is high, thereby being beneficial to industrial production.
Description
Technical Field
The invention belongs to the technical field of organic synthesis, and particularly relates to a method for preparing 4,4' -dichlorodiphenyl sulfone.
Background
The 4,4' -dichloro diphenyl sulfone is a main raw material for preparing engineering plastics such as polysulfone, polyethersulfone and the like, is also an intermediate of dye, auxiliary agent, pesticide and the like, has excellent heat resistance, physical and mechanical properties, insulating properties and chemical resistance, is widely applied to the fields of engineering plastics, electronic appliances, aerospace, medicine and health and the like, has increased demand and is an important fine chemical product with development prospect.
The industrial production of 4,4' -dichlorodiphenyl sulfone mainly comprises chlorosulfonation method, sulfur trioxide method, sulfuric acid method, sulfoxide oxidation method and the like. The chlorosulfonic acid method and the sulfur trioxide method require strict control on the aspects of storage, transportation and use of raw materials used in the preparation process, and can generate a large amount of HCl gas and waste acid, thereby causing equipment corrosion and environmental pollution. The raw material used in the sulfuric acid method is concentrated sulfuric acid, the problems are avoided, the reaction conditions are harsh, and the product quality is poor. The method for preparing 4,4' -dichlorodiphenyl sulfone by sulfoxide oxidation is commonly used in industry at present, has mild reaction conditions, high reaction selectivity, easily available and easily reserved raw materials, and has good industrial economic benefit and great development prospect.
The sulfoxide oxidation method is that chlorobenzene and thionyl chloride undergo Friedel-crafts acylation reaction under the action of a catalyst to generate 4,4 '-dichloro diphenyl sulfoxide, and then undergo oxidation reaction under the condition of hydrogen peroxide mixed acid to obtain 4,4' -dichloro diphenyl sulfone. The catalyst commonly used in Friedel-crafts acylation reaction is anhydrous AlCl 3 Anhydrous AlCl 3 The catalyst exhibits high catalytic activity, and the acylation reaction of the aromatic compound which is weakly passivated like chlorobenzene also has high catalytic activity. AlCl 3 The presence of (2) plays a decisive role in the performance of the friedel-crafts acylation reaction. Research shows AlCl 3 Complexing with carbonyl groups to positively charge the carbonyl carbon in the acid chloride and in AlCl 3 Under the action of the catalyst, the carbon on the aromatic ring has very nucleophilic propertyThereby leading carbonyl carbocation to attack the aromatic ring rich in electrons to generate a molecule of HCl and generate electrophilic substitution reaction.
But using anhydrous AlCl 3 There are also some problems: for example, a large amount of waste acid and waste water are generated, equipment is easy to corrode, and environmental pollution is caused; in addition, the reaction needs a metered catalyst and emits a large amount of heat, so that isomer impurities are easy to generate, and the conversion rate of the product is influenced; and anhydrous AlCl 3 Although the catalyst is not recycled, the system after the reaction is homogeneous and the post-treatment is complex. There is therefore a need to improve upon conventional anhydrous AlCl 3 Improves the production process of 4,4' -dichlorodiphenyl sulfone.
Disclosure of Invention
In order to solve the above problems, an object of the present invention is to provide a method for preparing 4,4' -dichlorodiphenyl sulfone. Chlorobenzene is used as raw material and reaction solvent, and the used supported AlCl 3 The catalyst can be used as a stable multiphase Lewis acid catalyst, the catalyst can be reused with high efficiency, the production cost is greatly saved, the method is environment-friendly to equipment, and the obtained product has high purity and high conversion rate.
The invention aims to achieve the aim, and the aim is achieved by the following technical scheme:
a process for preparing 4,4' -dichlorodiphenyl sulfone comprising the steps of:
(1) chlorobenzene and supported AlCl 3 Stirring and mixing the catalyst uniformly, introducing nitrogen, dropwise adding thionyl chloride at the temperature of minus 15 ℃ to minus 5 ℃, after the dropwise adding is finished, preserving heat and reacting for 2-3 hours, filtering after the reaction is finished, wherein the obtained filter cake is the catalyst, washing the catalyst with methylene dichloride and drying the catalyst for reuse, and the obtained filtrate is 4,4' -dichlorobenzene sulfoxide oil phase;
the supported AlCl 3 The catalyst is PS-AlCl 3 (polystyrene-aluminum trichloride), SG-AlCl 3 (silica gel-aluminum trichloride) or SG-PS-AlCl 3 (silica gel-polystyrene-aluminum trichloride);
(2) heating the 4,4' -dichloro diphenyl sulfoxide oil phase prepared in the step (1) to 60-80 ℃, adding glacial acetic acid under stirring, and then dropwise adding H 2 O 2 And (3) performing oxidation reaction, after dropwise adding, performing heat preservation reaction for 1.5-2.5 h, concentrating the obtained reaction solution until the concentration of 4,4 '-dichlorodiphenyl sulfone in the reaction solution is 28-30% after the reaction is finished, heating to 60 ℃ for dissolution, cooling and crystallizing to 10 ℃ at 20 ℃/h, filtering, and vacuum drying the obtained filter cake at 70 ℃ to obtain the high-purity 4,4' -dichlorodiphenyl sulfone.
The molar ratio of the thionyl chloride to the chlorobenzene in the step (1) is 1:6 to 9.
The sulfoxide chloride and the supported AlCl in the step (1) 3 The mass ratio of the catalyst is 1:0.06 to 0.1.
The dropping speed of the sulfoxide chloride in the step (1) is 0.5-0.75 g/min.
The supported AlCl in step (1) 3 The catalyst is prepared by the following steps: drying carbon tetrachloride and activated carrier and anhydrous AlCl 3 Adding the mixture into a reactor, mechanically stirring and refluxing the mixture for reaction for 3 to 4 hours under the nitrogen atmosphere, cooling the mixture to-5 ℃ after the reaction is finished to obtain a reaction liquid, and adding ice water into the reaction liquid to hydrolyze excessive AlCl 3 Filtering, washing the obtained filter cake with acetone and carbon tetrachloride for 2 times, and vacuum drying at 60deg.C for 3 hr to obtain supported AlCl 3 A catalyst;
the carrier is SG, PS or SG-PS;
the carbon tetrachloride, the carrier and the anhydrous AlCl 3 The mass ratio of (3) is 17-20: 3 to 5:1, a step of;
the addition amount of the ice water is 20-25% of the mass of the reaction liquid.
The H in step (2) 2 O 2 The drop acceleration of (2) is 0.5-1 g/min.
The glacial acetic acid and H in the step (2) 2 O 2 The molar ratio of (2) is 1:1 to 2; the sulfoxide chloride and H 2 O 2 The molar ratio of (2) is 1-1.1: 1.2.
the SG-PS carrier is prepared by the following method:
(1) Firstly, soaking commercial spherical silica gel in 6mol/L HCl, wherein the volume ratio of the commercial spherical silica gel to the HCl is 1:1, a step of; soaking for 10 hours, washing with water to pH 7, vacuum drying at 100 ℃ for 5 hours to obtain activated silica gel, adding the activated silica gel, vinyl triethoxysilane and toluene into a reactor, bubbling nitrogen for 20 minutes, introducing ammonia gas, stirring at room temperature for 8 hours, performing suction filtration after the reaction is finished, washing the obtained filter cake with ethanol for 3-5 times, extracting with absolute ethanol for 10 hours, and finally vacuum drying at 50 ℃ to obtain vinyl triethoxysilane coupling silica gel;
the mass ratio of the activated silica gel to the vinyl triethoxysilane to the toluene is 10-12: 1: 35-40;
(2) Adding vinyltriethoxysilane coupling silica gel, polyvinylpyrrolidone, styrene, deionized water and absolute ethyl alcohol into a reactor, introducing nitrogen for protection, mechanically stirring and reacting for 3 hours to obtain a reaction liquid, heating the reaction liquid to 70 ℃, dripping an azodiisobutyronitrile ethanol solution with the mass concentration of 20% into the reaction liquid, continuing to react for 4 hours, respectively carrying out rope extraction on the product with toluene and absolute ethyl alcohol overnight, and finally carrying out vacuum drying at 50 ℃ to obtain an SG-PS carrier;
the mass ratio of the vinyl triethoxysilane coupling silica gel to the polyvinylpyrrolidone to the styrene to the deionized water to the absolute ethyl alcohol is 1:0.01 to 0.02:0.9 to 1:1:3 to 5;
the mass ratio of the azo diisobutyronitrile to the vinyl triethoxysilane coupling silica gel is 0.01-0.02: 1.
preferably, the carbon tetrachloride, the carrier and the anhydrous AlCl 3 The mass ratio of (2) is 18:4:1.
preferably, the mass ratio of the activated silica gel, the vinyltriethoxysilane and the toluene in the step (1) is 11:1:38.5; the mass ratio of the vinyltriethoxysilane coupled silica gel to the polyvinylpyrrolidone to the styrene to the deionized water to the absolute ethyl alcohol in the step (2) is 1:0.018:0.902:1:3.12; the mass ratio of the azodiisobutyronitrile to the vinyltriethoxysilane coupling silica gel is 0.01:1.
in the invention, chlorobenzene is used as a raw material and a reaction solvent, and the used supported AlCl 3 The catalyst can be used as a stable multiphase Lewis acid catalyst and a supported AlCl 3 The catalyst is easy to prepare and post-treat, and can be formed into a non-porous catalyst due to different carriersCatalyst in co-binding form, SG-AlCl 3 AlCl of (C) 3 React with Si-OH in SG to generate HCl, thus completing load; PS-AlCl 3 AlCl of (C) 3 Conjugation occurs with PS to realize a supported catalyst; the supported catalyst has good regeneration performance and is environment-friendly, solid-liquid separation can be realized by filtering after the reaction is finished, dichloromethane or diethyl ether is used for washing, and the supported catalyst can be reused for 4-5 times after being dried; and anhydrous AlCl 3 Compared with the method, the method has the advantages that the steric hindrance is large, the generation of para-sulfoxide is facilitated, the reaction activity of ortho-position can be further weakened by reducing the reaction temperature, and the conversion rate of products is improved; in addition, the supported catalyst has more active sites, which is beneficial to improving the yield.
Compared with the prior art, the invention has the following advantages:
1) The method for preparing 4,4' -dichloro diphenyl sulfone adopts the supported AlCl in the Friedel-crafts acylation reaction stage 3 The solid acid catalyst has rich surface active sites, and certain steric hindrance can effectively improve the selectivity of the reaction and the purity of the product.
2) The invention uses the supported AlCl 3 The catalyst has the advantages of mild reaction conditions, high yield, short reaction time, simple working process, low cost, convenient preparation of the catalyst, realization of solid-liquid separation by filtration, simple post-treatment, repeated use for a plurality of times, great saving of process cost and reduction of unnecessary risks and wastes generated by a conventional homogeneous system.
3) The method has the advantages of simple process, less waste, low cost, multiple circulation of the catalyst, high product purity, high content of more than 99.9 percent, low sulfoxide isomer content of less than 2 percent, high yield of more than 98 percent and high economic benefit, and is beneficial to industrial production.
Drawings
FIG. 1 is a high performance liquid chromatogram of 4,4' -dichlorodiphenyl sulfone prepared in example 1 of the present invention.
Detailed Description
The foregoing is further elaborated by the following description of embodiments of the present invention, which are given by way of example only, and should not be construed as limiting the scope of the present invention. All techniques implemented based on the above description of the invention are within the scope of the invention.
Example 1
0.85kg of carbon tetrachloride, 0.15kg of activated and dried PS and 0.05kg of anhydrous AlCl 3 Adding the mixture into a reactor, mechanically stirring and refluxing the mixture for reaction for 4 hours under the nitrogen atmosphere, cooling the mixture to-5 ℃ after the reaction is finished to obtain a reaction solution, and adding ice water into the reaction solution to hydrolyze excessive AlCl 3 Filtering, washing the obtained filter cake with acetone and carbon tetrachloride for 1 time, and vacuum drying at 60deg.C for 3 hr to obtain PS-AlCl 3 。
135.1g of chlorobenzene were reacted with 1.5g of PS-AlCl 3 Stirring, mixing, introducing nitrogen, dropwise adding 23.8g of thionyl chloride at-15deg.C with the dropwise adding speed of 0.5g/min, reacting for 3 hr under heat preservation, and filtering to obtain PS-AlCl 3 Washing with dichloromethane, oven drying, and collecting filtrate which is 4,4' -dichlorobenzyl sulfoxide oil phase;
heating the oil phase of the prepared 4,4' -dichlorobenzyl sulfoxide to 60 ℃, adding 7.2g of glacial acetic acid under stirring, and then dripping 7.4g of H 2 O 2 Oxidation reaction is carried out, H 2 O 2 The dropping speed of the catalyst is 0.5g/min, after the completion of the dropping, the reaction is carried out for 2.5 hours under the condition of heat preservation, partial solvent is removed by reduced pressure distillation until the concentration of 4,4 '-dichlorodiphenyl sulfone in the reaction liquid is 28 percent, the solution is dissolved at 60 ℃, then cooled and crystallized to 10 ℃ at 20 ℃/h, the solution is filtered, the obtained filter cake is dried at 70 ℃ in vacuum, and 56.51g of high-purity 4,4' -dichlorodiphenyl sulfone is obtained, the yield is 98.4 percent, and the liquid phase purity is 99.9 percent. The high performance liquid chromatogram is shown in figure 1.
Example 2
1kg of carbon tetrachloride, 0.25kg of activated and dried PS and 0.05kg of anhydrous AlCl 3 Adding the mixture into a reactor, mechanically stirring and refluxing the mixture for reaction for 4 hours under the nitrogen atmosphere, cooling the mixture to-5 ℃ after the reaction is finished to obtain a reaction solution, and adding ice water into the reaction solution to hydrolyze excessive AlCl 3 Filtering, washing the obtained filter cake with acetone and carbon tetrachloride, and vacuum drying at 60deg.C3h to obtain PS-AlCl 3 。
236.4g of chlorobenzene and 2.28g of PS-AlCl were reacted 3 Stirring, mixing, introducing nitrogen, adding 35.69g sulfoxide chloride dropwise at-10deg.C at a rate of 0.6g/min, reacting for 2.5 hr under heat preservation, and filtering to obtain PS-AlCl 3 Washing the catalyst with dichloromethane, drying for later use, and collecting filtrate to obtain 4,4' -dichlorobenzene sulfoxide oil phase;
heating the oil phase of the prepared 4,4' -dichlorobenzyl sulfoxide to 70 ℃, adding 9.9g of glacial acetic acid under stirring, and then dripping 11.2g of H 2 O 2 Oxidation reaction is carried out, H 2 O 2 The dropping speed of the catalyst is 0.6g/min, after the completion of the dropping, the reaction is carried out for 2.5 hours under the condition of heat preservation, partial solvent is removed by reduced pressure distillation until the concentration of 4,4 '-dichlorodiphenyl sulfone in the reaction liquid is 29 percent, the solution is dissolved at 60 ℃, then cooled and crystallized to 10 ℃ at 20 ℃/h, the solution is filtered, the obtained filter cake is dried at 70 ℃ in vacuum, and 85.2g of high-purity 4,4' -dichlorodiphenyl sulfone is obtained, the yield is 98.9 percent, and the liquid phase purity is 99.9 percent.
Example 3
0.9kg of carbon tetrachloride, 0.2kg of activated and dried SG and 0.05kg of anhydrous AlCl 3 Adding the mixture into a reactor, mechanically stirring and refluxing the mixture for reaction for 3 hours under the nitrogen atmosphere, cooling the mixture to-5 ℃ after the reaction is finished to obtain a reaction solution, and adding ice water into the reaction solution to hydrolyze excessive AlCl 3 Filtering, washing the obtained filter cake with acetone and carbon tetrachloride, and vacuum drying at 60deg.C for 3 hr to obtain SG-AlCl 3 。
225.12g of chlorobenzene and 2.08g of SG-AlCl 3 Stirring, mixing, introducing nitrogen, dropwise adding 29.74g of thionyl chloride at-10deg.C at a dropwise speed of 0.75g/min, reacting for 2 hr under heat preservation, and filtering to obtain SG-AlCl 3 Washing the catalyst with dichloromethane, drying for later use, and collecting filtrate to obtain 4,4' -dichlorobenzene sulfoxide oil phase;
heating the oil phase of the prepared 4,4' -dichlorobenzyl sulfoxide to 80 ℃, adding 9.75g of glacial acetic acid under stirring, and then dropwise adding 10.2g of H 2 O 2 Oxidation reaction is carried out, H 2 O 2 Is 0.8g/min,after the dripping is finished, carrying out heat preservation reaction for 2 hours, decompressing and distilling to remove part of solvent, until the concentration of 4,4 '-dichlorodiphenyl sulfone in the reaction liquid is 29%, dissolving at 60 ℃, cooling and crystallizing at 20 ℃/h to 10 ℃, filtering, and vacuum drying the obtained filter cake at 70 ℃ to obtain 70.85g of high-purity 4,4' -dichlorodiphenyl sulfone, wherein the yield is 98.7%, and the liquid phase purity is 99.9%.
Example 4
Firstly, soaking commercial spherical silica gel in 6mol/L HCl, wherein the volume ratio of the commercial spherical silica gel to the HCl is 1:1, a step of; soaking for 10 hours, washing with water to reach pH of 7, vacuum drying at 100 ℃ for 5 hours to obtain activated silica gel, adding 1.1kg of activated silica gel, 0.1kg of vinyltriethoxysilane and 3.85kg of toluene into a reactor, bubbling nitrogen for 20 minutes, introducing ammonia gas, stirring at room temperature for 8 hours, performing suction filtration after the reaction is finished, washing the obtained filter cake with ethanol for 3 times, extracting with absolute ethanol for 10 hours, and finally vacuum drying at 50 ℃ to obtain vinyltriethoxysilane coupled silica gel;
adding 1kg of vinyltriethoxysilane coupling silica gel, 0.018kg of polyvinylpyrrolidone, 0.902kg of styrene, 1kg of deionized water and 3.12kg of absolute ethyl alcohol into a reactor, introducing nitrogen for protection, mechanically stirring and reacting for 3 hours to obtain a reaction liquid, heating the reaction liquid to 70 ℃, then dripping 0.05kg of 20% azodiisobutyronitrile ethanol solution by mass concentration into the reaction liquid, continuously reacting for 4 hours, respectively carrying out cable extraction on the product with toluene and absolute ethyl alcohol overnight, and finally carrying out vacuum drying at 50 ℃ to obtain the SG-PS carrier.
0.9kg of carbon tetrachloride, 0.2kg of SG-PS dried after activation and 0.05kg of anhydrous AlCl 3 Adding the mixture into a reactor, mechanically stirring and refluxing the mixture for reaction for 4 hours under the nitrogen atmosphere, cooling the mixture to-5 ℃ after the reaction is finished to obtain a reaction solution, and adding ice water into the reaction solution to hydrolyze excessive AlCl 3 Filtering, washing the obtained filter cake with acetone and carbon tetrachloride, and vacuum drying at 60deg.C for 3 hr to obtain SG-PS-AlCl 3 。
354.5g of chlorobenzene and 3.33g of SG-PS-AlCl 3 Stirring, mixing, introducing nitrogen, adding 41.64g sulfoxide chloride dropwise at-15deg.C at a dropping speed of 0.75g/min, reacting for 3 hr under heat preservation, and filtering to obtain SG-PS-AlCl 3 Washing the catalyst with dichloromethane, drying for later use, and collecting filtrate to obtain 4,4' -dichlorobenzene sulfoxide oil phase;
heating the oil phase of the prepared 4,4' -dichlorobenzyl sulfoxide to 75 ℃, adding 18.49g of glacial acetic acid under stirring, and then dripping 14.3g of H 2 O 2 Oxidation reaction is carried out, H 2 O 2 The dropping speed of the catalyst is 1.0g/min, after the completion of the dropping, the reaction is carried out for 2.5 hours under the condition of heat preservation, partial solvent is removed by reduced pressure distillation until the concentration of 4,4 '-dichlorodiphenyl sulfone in the reaction liquid is 30 percent, the solution is dissolved at 60 ℃, then the temperature is reduced to 10 ℃ by 20 ℃/h, crystallization is carried out, filtration is carried out, the obtained filter cake is dried at 70 ℃ in vacuum, and 99.7g of high-purity 4,4' -dichlorodiphenyl sulfone is obtained, the yield is 99.2 percent, and the purity of liquid phase is 99.9 percent.
Example 5
Firstly, soaking commercial spherical silica gel in 6mol/L HCl, wherein the volume ratio of the commercial spherical silica gel to the HCl is 1:1, a step of; soaking for 10 hours, washing with water to pH 7, vacuum drying at 100 ℃ for 5 hours to obtain activated silica gel, adding 2kg of activated silica gel, 0.2kg of vinyltriethoxysilane and 7kg of toluene into a reactor, bubbling nitrogen for 20 minutes, introducing ammonia gas, stirring at room temperature for 8 hours, filtering after the reaction is finished, washing the obtained filter cake with ethanol for 5 times, extracting with absolute ethanol for 10 hours, and finally vacuum drying at 50 ℃ to obtain vinyltriethoxysilane coupling silica gel;
adding 2kg of vinyltriethoxysilane coupling silica gel, 0.02kg of polyvinylpyrrolidone, 1.804kg of styrene, 1.8kg of deionized water and 6kg of absolute ethyl alcohol into a reactor, introducing nitrogen for protection, mechanically stirring and reacting for 3 hours to obtain a reaction liquid, heating the reaction liquid to 70 ℃, then dripping 0.2kg of azobisisobutyronitrile ethanol solution with the mass concentration of 20% into the reaction liquid, continuously reacting for 4 hours, respectively carrying out cable extraction on the product with toluene and absolute ethyl alcohol overnight, and finally carrying out vacuum drying at 50 ℃ to obtain the SG-PS carrier.
0.95kg of carbon tetrachloride, 0.2kg of SG-PS dried after activation and 0.05kg of anhydrous AlCl 3 Adding the mixture into a reactor, mechanically stirring and refluxing the mixture for reaction for 3.5 hours under the nitrogen atmosphere, cooling the mixture to-5 ℃ after the reaction is finished to obtain a reaction liquid, and adding ice water into the reaction liquid to hydrolyze excessive AlCl 3 Filtering to obtain a filter cakeWashing with acetone and carbon tetrachloride, and vacuum drying at 60deg.C for 3 hr to obtain SG-PS-AlCl 3 。
198.1g of chlorobenzene and 2.6g of SG-PS-AlCl are reacted 3 Stirring, mixing, introducing nitrogen, dropwise adding 26.17g of thionyl chloride at-5deg.C at a dropwise speed of 0.70g/min, reacting for 2 hr under heat preservation, and filtering to obtain SG-PS-AlCl 3 Washing the catalyst with dichloromethane, drying for later use, and collecting filtrate to obtain 4,4' -dichlorobenzene sulfoxide oil phase;
heating the oil phase of the prepared 4,4' -dichlorobenzyl sulfoxide to 70 ℃, adding 10.57g of glacial acetic acid under stirring, and then dripping 8.2g of H 2 O 2 Oxidation reaction is carried out, H 2 O 2 The dropping speed of the catalyst is 0.8g/min, after the completion of the dropping, the reaction is carried out for 2.5 hours under the condition of heat preservation, partial solvent is removed by reduced pressure distillation until the concentration of 4,4 '-dichlorodiphenyl sulfone in the reaction liquid is 30 percent, the solution is dissolved at 60 ℃, then cooled and crystallized to 10 ℃ at 20 ℃/h, the solution is filtered, the obtained filter cake is dried at 70 ℃ in vacuum, 62.41g of high-purity 4,4' -dichlorodiphenyl sulfone is obtained, the yield is 98.8 percent, and the liquid phase purity is 99.9 percent.
While the foregoing describes the embodiments of the present invention, it is not intended to limit the scope of the present invention, and various modifications or variations may be made by those skilled in the art without the need for inventive effort on the basis of the technical solutions of the present invention.
Claims (10)
1. A process for preparing 4,4' -dichlorodiphenyl sulfone, characterized by: the method comprises the following steps:
(1) chlorobenzene and supported AlCl 3 Stirring and mixing the catalyst uniformly, introducing nitrogen, dropwise adding thionyl chloride at the temperature of minus 15 ℃ to minus 5 ℃, after the dropwise adding is finished, preserving heat and reacting for 2-3 hours, filtering after the reaction is finished, wherein the obtained filter cake is the catalyst, washing the catalyst with methylene dichloride and drying the catalyst for reuse, and the obtained filtrate is 4,4' -dichlorobenzene sulfoxide oil phase;
the supported AlCl 3 The catalyst is PS-AlCl 3 、SG-AlCl 3 Or SG-PS-AlCl 3 ；
(2) Heating the 4,4' -dichloro diphenyl sulfoxide oil phase prepared in the step (1) to 60-80 ℃, adding glacial acetic acid under stirring, and then dropwise adding H 2 O 2 And (3) performing oxidation reaction, after dropwise adding, performing heat preservation reaction for 1.5-2.5 h, concentrating the obtained reaction solution until the concentration of 4,4 '-dichlorodiphenyl sulfone in the reaction solution is 28-30% after the reaction is finished, heating to 60 ℃ for dissolution, cooling and crystallizing to 10 ℃ at 20 ℃/h, filtering, and vacuum drying the obtained filter cake at 70 ℃ to obtain the high-purity 4,4' -dichlorodiphenyl sulfone.
2. The method for preparing 4,4' -dichlorodiphenyl sulfone according to claim 1, wherein: the molar ratio of the thionyl chloride to the chlorobenzene in the step (1) is 1:6 to 9.
3. The method for preparing 4,4' -dichlorodiphenyl sulfone according to claim 1, wherein: the sulfoxide chloride and the supported AlCl in the step (1) 3 The mass ratio of the catalyst is 1:0.06 to 0.1.
4. The method for preparing 4,4' -dichlorodiphenyl sulfone according to claim 1, wherein: the dropping speed of the sulfoxide chloride in the step (1) is 0.5-0.75 g/min.
5. The method for preparing 4,4' -dichlorodiphenyl sulfone according to claim 1, wherein: the supported AlCl in step (1) 3 The catalyst is prepared by the following steps: drying carbon tetrachloride and activated carrier and anhydrous AlCl 3 Adding the mixture into a reactor, mechanically stirring and refluxing the mixture for reaction for 3 to 4 hours under the nitrogen atmosphere, cooling the mixture to-5 ℃ after the reaction is finished to obtain a reaction liquid, and adding ice water into the reaction liquid to hydrolyze excessive AlCl 3 Filtering, washing the obtained filter cake with acetone and carbon tetrachloride for 2 times, and vacuum drying at 60deg.C for 3 hr to obtain supported AlCl 3 A catalyst;
the carrier is SG, PS or SG-PS;
the carbon tetrachloride, the carrier and the anhydrous AlCl 3 The mass ratio of (3) is 17-20: 3 to 5:1, a step of;
the addition amount of the ice water is 20-25% of the mass of the reaction liquid.
6. The method for preparing 4,4' -dichlorodiphenyl sulfone according to claim 1, wherein: the H in step (2) 2 O 2 The drop acceleration of (2) is 0.5-1 g/min.
7. The method for preparing 4,4' -dichlorodiphenyl sulfone according to claim 1, wherein: the glacial acetic acid and H in the step (2) 2 O 2 The molar ratio of (2) is 1:1 to 2; the H is 2 O 2 The molar ratio of the catalyst to the thionyl chloride is 1.2:1 to 1.1.
8. The method for preparing 4,4' -dichlorodiphenyl sulfone according to claim 5, wherein: the SG-PS carrier is prepared by the following method:
(1) Firstly, soaking commercial spherical silica gel in 6mol/L HCl, wherein the volume ratio of the commercial spherical silica gel to the HCl is 1:1, a step of; soaking for 10 hours, washing with water to pH 7, vacuum drying at 100 ℃ for 5 hours to obtain activated silica gel, adding the activated silica gel, vinyl triethoxysilane and toluene into a reactor, bubbling nitrogen for 20 minutes, introducing ammonia gas, stirring at room temperature for 8 hours, performing suction filtration after the reaction is finished, washing the obtained filter cake with ethanol for 3-5 times, extracting with absolute ethanol for 10 hours, and finally vacuum drying at 50 ℃ to obtain vinyl triethoxysilane coupling silica gel;
the mass ratio of the activated silica gel to the vinyl triethoxysilane to the toluene is 10-12: 1: 35-40;
(2) Adding vinyltriethoxysilane coupling silica gel, polyvinylpyrrolidone, styrene, deionized water and absolute ethyl alcohol into a reactor, introducing nitrogen for protection, mechanically stirring and reacting for 3 hours to obtain a reaction liquid, heating the reaction liquid to 70 ℃, dripping an azodiisobutyronitrile ethanol solution with the mass concentration of 20% into the reaction liquid, continuing to react for 4 hours, respectively carrying out rope extraction on the product with toluene and absolute ethyl alcohol overnight, and finally carrying out vacuum drying at 50 ℃ to obtain an SG-PS carrier;
the mass ratio of the vinyl triethoxysilane coupling silica gel to the polyvinylpyrrolidone to the styrene to the deionized water to the absolute ethyl alcohol is 1:0.01 to 0.02:0.9 to 1:1:3 to 5;
the mass ratio of the azo diisobutyronitrile to the vinyl triethoxysilane coupling silica gel is 0.01-0.02: 1.
9. the method for preparing 4,4' -dichlorodiphenyl sulfone according to claim 5, wherein: the carbon tetrachloride, the carrier and the anhydrous AlCl 3 The mass ratio of (2) is 18:4:1.
10. the method for preparing 4,4' -dichlorodiphenyl sulfone according to claim 8, wherein: the mass ratio of the activated silica gel to the vinyltriethoxysilane to the toluene in the step (1) is 11:1:38.5; the mass ratio of the vinyltriethoxysilane coupled silica gel to the polyvinylpyrrolidone to the styrene to the deionized water to the absolute ethyl alcohol in the step (2) is 1:0.018:0.902:1:3.12; the mass ratio of the azodiisobutyronitrile to the vinyltriethoxysilane coupling silica gel is 0.01:1.
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