CN117816152A - Preparation method of selective debenzylation catalyst - Google Patents
Preparation method of selective debenzylation catalyst Download PDFInfo
- Publication number
- CN117816152A CN117816152A CN202311834396.5A CN202311834396A CN117816152A CN 117816152 A CN117816152 A CN 117816152A CN 202311834396 A CN202311834396 A CN 202311834396A CN 117816152 A CN117816152 A CN 117816152A
- Authority
- CN
- China
- Prior art keywords
- acid solution
- mixed acid
- selective debenzylation
- selective
- activated carbon
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 239000003054 catalyst Substances 0.000 title claims abstract description 71
- 238000006264 debenzylation reaction Methods 0.000 title claims abstract description 63
- 238000002360 preparation method Methods 0.000 title abstract description 32
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims abstract description 105
- 239000002253 acid Substances 0.000 claims abstract description 68
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 claims abstract description 48
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 37
- KDLHZDBZIXYQEI-UHFFFAOYSA-N Palladium Chemical compound [Pd] KDLHZDBZIXYQEI-UHFFFAOYSA-N 0.000 claims abstract description 36
- 238000003756 stirring Methods 0.000 claims abstract description 30
- 238000001914 filtration Methods 0.000 claims abstract description 26
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 claims abstract description 24
- 229910017604 nitric acid Inorganic materials 0.000 claims abstract description 24
- 238000001035 drying Methods 0.000 claims abstract description 16
- 229910052763 palladium Inorganic materials 0.000 claims abstract description 16
- 238000002156 mixing Methods 0.000 claims abstract description 14
- 239000008367 deionised water Substances 0.000 claims abstract description 13
- 229910021641 deionized water Inorganic materials 0.000 claims abstract description 13
- 230000007935 neutral effect Effects 0.000 claims abstract description 13
- 238000005406 washing Methods 0.000 claims abstract description 13
- 229910052799 carbon Inorganic materials 0.000 claims description 41
- 239000000463 material Substances 0.000 claims description 24
- 238000000034 method Methods 0.000 claims description 15
- 239000006185 dispersion Substances 0.000 claims description 12
- PIBWKRNGBLPSSY-UHFFFAOYSA-L palladium(II) chloride Chemical compound Cl[Pd]Cl PIBWKRNGBLPSSY-UHFFFAOYSA-L 0.000 claims description 12
- 239000002245 particle Substances 0.000 claims description 12
- GPNDARIEYHPYAY-UHFFFAOYSA-N palladium(ii) nitrate Chemical compound [Pd+2].[O-][N+]([O-])=O.[O-][N+]([O-])=O GPNDARIEYHPYAY-UHFFFAOYSA-N 0.000 claims description 3
- ZLMJMSJWJFRBEC-UHFFFAOYSA-N Potassium Chemical compound [K] ZLMJMSJWJFRBEC-UHFFFAOYSA-N 0.000 claims description 2
- 229910052700 potassium Inorganic materials 0.000 claims description 2
- 239000011591 potassium Substances 0.000 claims description 2
- 238000005470 impregnation Methods 0.000 abstract description 6
- 230000009467 reduction Effects 0.000 abstract description 6
- 239000000126 substance Substances 0.000 abstract description 5
- 238000005054 agglomeration Methods 0.000 abstract description 3
- 230000002776 aggregation Effects 0.000 abstract description 3
- 230000000694 effects Effects 0.000 abstract description 3
- 229910052751 metal Inorganic materials 0.000 abstract description 2
- 239000002184 metal Substances 0.000 abstract description 2
- 238000006243 chemical reaction Methods 0.000 description 14
- 125000001797 benzyl group Chemical group [H]C1=C([H])C([H])=C(C([H])=C1[H])C([H])([H])* 0.000 description 3
- 230000003197 catalytic effect Effects 0.000 description 3
- 239000002994 raw material Substances 0.000 description 3
- 238000007086 side reaction Methods 0.000 description 3
- 230000006641 stabilisation Effects 0.000 description 3
- 238000011105 stabilization Methods 0.000 description 3
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 2
- WYURNTSHIVDZCO-UHFFFAOYSA-N Tetrahydrofuran Chemical compound C1CCOC1 WYURNTSHIVDZCO-UHFFFAOYSA-N 0.000 description 2
- 238000006555 catalytic reaction Methods 0.000 description 2
- 125000000524 functional group Chemical group 0.000 description 2
- 239000001257 hydrogen Substances 0.000 description 2
- 229910052739 hydrogen Inorganic materials 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- YYAVAJYGTRYPEA-UHFFFAOYSA-N n,n-dibenzyl-4-chloroaniline Chemical compound C1=CC(Cl)=CC=C1N(CC=1C=CC=CC=1)CC1=CC=CC=C1 YYAVAJYGTRYPEA-UHFFFAOYSA-N 0.000 description 2
- QSNSCYSYFYORTR-UHFFFAOYSA-N 4-chloroaniline Chemical compound NC1=CC=C(Cl)C=C1 QSNSCYSYFYORTR-UHFFFAOYSA-N 0.000 description 1
- 150000001412 amines Chemical class 0.000 description 1
- 238000012512 characterization method Methods 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000005695 dehalogenation reaction Methods 0.000 description 1
- 238000007598 dipping method Methods 0.000 description 1
- 238000011156 evaluation Methods 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 238000007327 hydrogenolysis reaction Methods 0.000 description 1
- 230000007062 hydrolysis Effects 0.000 description 1
- 238000006460 hydrolysis reaction Methods 0.000 description 1
- 238000004811 liquid chromatography Methods 0.000 description 1
- 238000003541 multi-stage reaction Methods 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 239000001103 potassium chloride Substances 0.000 description 1
- WCUXLLCKKVVCTQ-UHFFFAOYSA-M potassium chloride Inorganic materials [Cl-].[K+] WCUXLLCKKVVCTQ-UHFFFAOYSA-M 0.000 description 1
- 235000011164 potassium chloride Nutrition 0.000 description 1
- 230000002028 premature Effects 0.000 description 1
- 125000002924 primary amino group Chemical group [H]N([H])* 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 125000006239 protecting group Chemical group 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
- 238000003786 synthesis reaction Methods 0.000 description 1
- YLQBMQCUIZJEEH-UHFFFAOYSA-N tetrahydrofuran Natural products C=1C=COC=1 YLQBMQCUIZJEEH-UHFFFAOYSA-N 0.000 description 1
Landscapes
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
- Catalysts (AREA)
Abstract
The invention discloses a preparation method of a selective debenzylation catalyst, which comprises the following steps: washing the activated carbon with deionized water to be neutral, filtering, and drying to obtain treated activated carbon; step two, mixing a hydrochloric acid solution and a nitric acid solution to obtain a mixed acid solution; step three, dissolving a palladium source in the mixed acid solution to obtain a mixed acid solution containing active components; step four, placing the treated activated carbon in a mixed acid solution containing active components, and stirring until the activated carbon is uniformly dispersed; and fifthly, continuously stirring the dispersed system to stabilize, filtering and drying to obtain the selective debenzylation catalyst. The preparation method of the selective debenzylation catalyst can effectively avoid the rapid reduction of active components into simple substances by a carrier in the initial stage of impregnation, and the simple substances are continuously grown as metal cores to form agglomeration along with the progress of impregnation, so that the surface active components of the obtained catalyst are more uniformly dispersed, and the activity and the selectivity are higher in the selective debenzylation reaction.
Description
Technical Field
The invention belongs to the technical field of catalysis, and particularly relates to a preparation method of a selective debenzylation catalyst.
Background
Organic synthesis is often a multi-step reaction, and due to the existence of functional groups in raw materials, side reactions often occur, protection of the functional groups and removal of the protecting groups at the end of the reaction are one of the effective means for avoiding the occurrence of the side reactions, such as instability of the-N groups in the free amine, benzyl needs to be used for protection in the reaction, and benzyl is removed after the end of the reaction, so that free amino is obtained again.
Pd/C catalyst is used as a widely used benzyl removal catalyst, and has remarkable catalytic effect in catalytic debenzylation reaction, but the Pd/C catalyst adopted at present cannot avoid the occurrence of undesired side reactions, such as dehalogenation process which is often accompanied. Therefore, it is a key to solve the above technical problems to provide a catalyst with high-efficiency selective debenzylation.
Disclosure of Invention
The invention aims to solve the technical problem of providing a preparation method of a selective debenzylation catalyst aiming at the defects of the prior art. The preparation method of the selective debenzylation catalyst comprises the steps of placing active carbon in a mixed acid solution containing active components for stabilization, effectively avoiding the rapid reduction of the active components into simple substances by a carrier in the initial stage of impregnation, and then continuing growing the simple substances as metal cores along with the progress of impregnation to form agglomeration.
In order to solve the technical problems, the invention adopts the following technical scheme: a method for preparing a selective debenzylation catalyst, which is characterized by comprising the following steps:
washing the activated carbon with deionized water to be neutral, filtering, and drying until the water content is less than 1wt% to obtain the treated activated carbon;
step two, mixing a hydrochloric acid solution and a nitric acid solution to obtain a mixed acid solution;
step three, dissolving a palladium source in the mixed acid solution obtained in the step two to obtain a mixed acid solution containing active components;
step four, placing the treated active carbon in the step three in the mixed acid solution containing the active components, and stirring until the active carbon is uniformly dispersed;
and fifthly, continuously stirring the system after the dispersion in the step IV to stabilize, filtering to obtain a stabilized material, and drying the stabilized material until the water content is less than 1wt% to obtain the selective debenzylation catalyst.
The preparation method of the selective debenzylation catalyst is characterized in that in the first step, the particle size of the activated carbon is 200-400 meshes, and the specific surface area is more than 1000m 2 /g。
The preparation method of the selective debenzylation catalyst is characterized in that in the second step, the mass of the nitric acid solution is 4 times that of the hydrochloric acid solution, the mass percentage of the hydrochloric acid solution is 1% -20%, and the mass percentage of the nitric acid solution is 1% -20%.
The preparation method of the selective debenzylation catalyst is characterized in that the mass percentage of the hydrochloric acid solution is 3.5-10%, and the mass percentage of the nitric acid solution is 10-20%.
The preparation method of the selective debenzylation catalyst is characterized in that in the second step, the mass percentage of the hydrochloric acid solution is 10%, and the mass percentage of the nitric acid solution is 10%.
The preparation method of the selective debenzylation catalyst is characterized in that in the third step, the palladium source comprises palladium chloride, palladium nitrate or potassium chloropalladate; in the third step, the mass of the mixed acid solution is 80-200 times of the mass of palladium.
The preparation method of the selective debenzylation catalyst is characterized in that in the fourth step, the mass of the mixed acid solution in the mixed acid solution containing the active components is 4-10.5 times of the mass of the treated active carbon.
The preparation method of the selective debenzylation catalyst is characterized in that the mass of the mixed acid solution is 5-8 times of the mass of the treated activated carbon.
The preparation method of the selective debenzylation catalyst is characterized in that in the fifth step, the continuous stirring time is 2-24 hours.
The preparation method of the selective debenzylation catalyst is characterized in that the continuous stirring time is 2-8 hours.
The reaction equation of the invention is:
compared with the prior art, the invention has the following advantages:
1. the preparation method of the selective debenzylation catalyst provided by the invention creatively provides a method for preparing the selective debenzylation catalyst by effectively avoiding the premature and too fast reduction of the catalyst based on the influence of the reduction stage of the active component on the product catalyst performance in the impregnation reaction process of the active component and the carrier, and the catalyst obtained by adopting the preparation method for limiting the pre-reduction has the characteristics of obviously improved activity and selectivity.
2. The preparation method of the selective debenzylation catalyst comprises the steps of placing active carbon in a mixed acid solution containing active components for stabilization, effectively avoiding the reduction of the active components into simple substances by a carrier in the initial stage of impregnation, avoiding agglomeration, ensuring that the active components are dispersed more uniformly, and ensuring that the obtained selective debenzylation catalyst has higher activity and selectivity.
3. The preparation method of the selective debenzylation catalyst comprises the steps of mixing a nitric acid solution and a hydrochloric acid solution to obtain a mixed acid solution, wherein the mixed acid solution is used as an impregnating stable reaction system of active components on carrier active carbon, so that the acid sites on the surface of the product catalyst can be effectively improved, and hydrogenolysis is promoted to be carried out in the debenzylation reaction direction.
4. Preferably, in the preparation method of the selective debenzylation catalyst, the mass percentage of the hydrochloric acid solution is 3% -10%, the mass percentage of the nitric acid solution is 10% -20%, the mass of the mixed acid solution is 5-8 times of the mass of the treated active carbon, the stable dipping time is 2-8 hours, and the selective debenzylation catalyst is obtained by adopting the method of the invention, wherein the selectivity can be up to 99% in the limited acid solution mass percentage, raw material proportion and reaction parameters.
The technical scheme of the invention is further described in detail below with reference to the examples.
Detailed Description
Example 1
The embodiment provides a preparation method of a selective debenzylation catalyst, which comprises the following steps:
washing the activated carbon with deionized water to be neutral, filtering, and drying in a baking oven at 120 ℃ until the water content is less than 1wt% to obtain the treated activated carbon; the particle size of the active carbon is 200-400 meshes, and the specific surface area is more than 1000m 2 /g；
Step two, mixing 100g of hydrochloric acid solution with the mass percentage of 10% with 400g of nitric acid solution with the mass percentage of 10% to obtain a mixed acid solution;
step three, dissolving palladium chloride containing 5g of palladium in the mixed acid solution obtained in the step two to obtain a mixed acid solution containing active components;
step four, placing 95g of the treated active carbon in the step three in the mixed acid solution containing the active components, and stirring at normal temperature until the active carbon is uniformly dispersed; the normal temperature is 20-25 ℃;
and fifthly, continuously stirring the system after the fourth dispersion for 8 hours to stabilize, filtering to obtain a stabilized material, and placing the stabilized material in a 105 ℃ oven to bake until the water content is less than 1wt%, thus obtaining the selective debenzylation catalyst.
Example 2
The embodiment provides a preparation method of a selective debenzylation catalyst, which comprises the following steps:
washing the activated carbon with deionized water to be neutral, filtering, and drying in a baking oven at 120 ℃ until the water content is less than 1wt% to obtain the treated activated carbon; the particle size of the active carbon is 200-400 meshes, and the specific surface area is more than 1000m 2 /g；
Step two, mixing 100g of hydrochloric acid solution with the mass percentage of 10% with 400g of nitric acid solution with the mass percentage of 10% to obtain a mixed acid solution;
step three, dissolving palladium chloride containing 5g of palladium in the mixed acid solution obtained in the step two to obtain a mixed acid solution containing active components;
step four, placing 95g of the treated active carbon in the step three in the mixed acid solution containing the active components, and stirring at normal temperature until the active carbon is uniformly dispersed; the normal temperature is 20-25 ℃;
and fifthly, continuously stirring the system after the fourth dispersion for 2 hours to stabilize, filtering to obtain a stabilized material, and placing the stabilized material in a 105 ℃ oven to bake until the water content is less than 1wt%, thus obtaining the selective debenzylation catalyst.
Example 3
The embodiment provides a preparation method of a selective debenzylation catalyst, which comprises the following steps:
washing the activated carbon with deionized water to be neutral, filtering, and drying in a baking oven at 120 ℃ until the water content is less than 1wt% to obtain the treated activated carbon; the particle size of the active carbon is 200-400 meshes, and the specific surface area is more than 1000m 2 /g；
Step two, mixing 100g of hydrochloric acid solution with the mass percentage of 10% with 400g of nitric acid solution with the mass percentage of 10% to obtain a mixed acid solution;
step three, dissolving palladium chloride containing 5g of palladium in the mixed acid solution obtained in the step two to obtain a mixed acid solution containing active components;
step four, placing 95g of the treated active carbon in the step three in the mixed acid solution containing the active components, and stirring at normal temperature until the active carbon is uniformly dispersed; the normal temperature is 20-25 ℃;
and fifthly, continuously stirring the system after the fourth dispersion for 24 hours to stabilize, filtering to obtain a stabilized material, and placing the stabilized material in a 105 ℃ oven to bake until the water content is less than 1wt%, thus obtaining the selective debenzylation catalyst.
Example 4
The embodiment provides a preparation method of a selective debenzylation catalyst, which comprises the following steps:
washing the activated carbon with deionized water to be neutral, filtering, and drying in a baking oven at 120 ℃ until the water content is less than 1wt% to obtain the treated activated carbon; the particle size of the active carbon is 200-400 meshes, and the specific surface area is more than 1000m 2 /g；
Step two, mixing 100g of hydrochloric acid solution with the mass percentage of 10% with 400g of nitric acid solution with the mass percentage of 20% to obtain a mixed acid solution;
step three, dissolving palladium chloride containing 5g of palladium in the mixed acid solution obtained in the step two to obtain a mixed acid solution containing active components;
step four, placing 95g of the treated active carbon in the step three in the mixed acid solution containing the active components, and stirring at normal temperature until the active carbon is uniformly dispersed; the normal temperature is 20-25 ℃;
and fifthly, continuously stirring the system after the fourth dispersion for 8 hours to stabilize, filtering to obtain a stabilized material, and placing the stabilized material in a 105 ℃ oven to bake until the water content is less than 1wt%, thus obtaining the selective debenzylation catalyst.
Example 5
The embodiment provides a preparation method of a selective debenzylation catalyst, which comprises the following steps:
washing the activated carbon with deionized water to be neutral, filtering, and drying in a baking oven at 120 ℃ until the water content is less than 1wt% to obtain the treated activated carbon; the particle size of the active carbon is 200-400 meshes, and the specific surface area is more than 1000m 2 /g；
Step two, mixing 100g of hydrochloric acid solution with the mass percentage content of 3.5% with 400g of nitric acid solution with the mass percentage content of 10% to obtain a mixed acid solution;
step three, dissolving palladium chloride containing 5g of palladium in the mixed acid solution obtained in the step two to obtain a mixed acid solution containing active components;
step four, placing 95g of the treated active carbon in the step three in the mixed acid solution containing the active components, and stirring at normal temperature until the active carbon is uniformly dispersed; the normal temperature is 20-25 ℃;
and fifthly, continuously stirring the system after the fourth dispersion for 8 hours to stabilize, filtering to obtain a stabilized material, and placing the stabilized material in a 105 ℃ oven to bake until the water content is less than 1wt%, thus obtaining the selective debenzylation catalyst.
Example 6
The embodiment provides a preparation method of a selective debenzylation catalyst, which comprises the following steps:
washing the activated carbon with deionized water to be neutral, filtering, and drying in a baking oven at 120 ℃ until the water content is less than 1wt% to obtain the treated activated carbon; the particle size of the active carbon is 200-400 meshes, and the specific surface area is more than 1000m 2 /g；
Step two, mixing 150g of hydrochloric acid solution with the mass percentage of 10% with 600g of nitric acid solution with the mass percentage of 10% to obtain a mixed acid solution;
step three, dissolving palladium chloride containing 5g of palladium in the mixed acid solution obtained in the step two to obtain a mixed acid solution containing active components;
step four, placing 95g of the treated active carbon in the step three in the mixed acid solution containing the active components, and stirring at normal temperature until the active carbon is uniformly dispersed; the normal temperature is 20-25 ℃;
and fifthly, continuously stirring the system after the fourth dispersion for 2 hours to stabilize, filtering to obtain a stabilized material, and placing the stabilized material in a 105 ℃ oven to bake until the water content is less than 1wt%, thus obtaining the selective debenzylation catalyst.
Example 7
The embodiment provides a preparation method of a selective debenzylation catalyst, which comprises the following steps:
washing the activated carbon with deionized water to be neutral, filtering, and drying in a baking oven at 120 ℃ until the water content is less than 1wt% to obtain the treated activated carbon; the particle size of the active carbon is 200-400 meshes, and the specific surface area is more than 1000m 2 /g；
Step two, mixing 100g of hydrochloric acid solution with the mass percentage of 10% with 400g of nitric acid solution with the mass percentage of 10% to obtain a mixed acid solution;
step three, dissolving palladium nitrate containing 5g of palladium in the mixed acid solution obtained in the step two to obtain a mixed acid solution containing active components;
step four, placing 95g of the treated active carbon in the step three in the mixed acid solution containing the active components, and stirring at normal temperature until the active carbon is uniformly dispersed; the normal temperature is 20-25 ℃;
and fifthly, continuously stirring the system after the fourth dispersion for 6 hours to stabilize, filtering to obtain a stabilized material, and placing the stabilized material in a 105 ℃ oven to bake until the water content is less than 1wt%, thus obtaining the selective debenzylation catalyst.
Example 8
The embodiment provides a preparation method of a selective debenzylation catalyst, which comprises the following steps:
washing the activated carbon with deionized water to be neutral, filtering, and drying in a baking oven at 120 ℃ until the water content is less than 1wt% to obtain the treated activated carbon; the particle size of the active carbon is 200-400 meshes, and the specific surface area is more than 1000m 2 /g；
Step two, mixing 150g of hydrochloric acid solution with the mass percentage of 10% with 600g of nitric acid solution with the mass percentage of 10% to obtain a mixed acid solution;
step three, dissolving 5g of palladium chloride potassium chloride in the mixed acid solution obtained in the step two to obtain a mixed acid solution containing active components;
step four, placing 95g of the treated active carbon in the step three in the mixed acid solution containing the active components, and stirring at normal temperature until the active carbon is uniformly dispersed; the normal temperature is 20-25 ℃;
and fifthly, continuously stirring the system after the fourth dispersion for 8 hours to stabilize, filtering to obtain a stabilized material, and placing the stabilized material in a 105 ℃ oven to bake until the water content is less than 1wt%, thus obtaining the selective debenzylation catalyst.
Example 9
The embodiment provides a preparation method of a selective debenzylation catalyst, which comprises the following steps:
washing the activated carbon with deionized water to be neutral, filtering, and drying in a baking oven at 120 ℃ until the water content is less than 1wt% to obtain the treated activated carbon; the particle size of the active carbon is 200-400 meshes, and the specific surface area is more than 1000m 2 /g；
Step two, mixing 80g of hydrochloric acid solution with the mass percentage of 1% with 320g of nitric acid solution with the mass percentage of 1% to obtain a mixed acid solution;
step three, dissolving palladium chloride containing 5g of palladium in the mixed acid solution obtained in the step two to obtain a mixed acid solution containing active components;
step four, placing 95g of the treated active carbon in the step three in the mixed acid solution containing the active components, and stirring at normal temperature until the active carbon is uniformly dispersed; the normal temperature is 20-25 ℃;
and fifthly, continuously stirring the system after the fourth dispersion for 12 hours to stabilize, filtering to obtain a stabilized material, and placing the stabilized material in a 105 ℃ oven to bake until the water content is less than 1wt%, thus obtaining the selective debenzylation catalyst.
Example 10
The embodiment provides a preparation method of a selective debenzylation catalyst, which comprises the following steps:
washing the activated carbon with deionized water to be neutral, filtering, and drying in a baking oven at 120 ℃ until the water content is less than 1wt% to obtain the treated activated carbon; the particle size of the active carbon is 200-400 meshes, and the specific surface area is more than 1000m 2 /g；
Step two, mixing 200g of hydrochloric acid solution with the mass percentage of 20% with 800g of nitric acid solution with the mass percentage of 20% to obtain a mixed acid solution;
step three, dissolving palladium chloride containing 5g of palladium in the mixed acid solution obtained in the step two to obtain a mixed acid solution containing active components;
step four, placing 95g of the treated active carbon in the step three in the mixed acid solution containing the active components, and stirring at normal temperature until the active carbon is uniformly dispersed; the normal temperature is 20-25 ℃;
and fifthly, continuously stirring the system after the fourth dispersion for 20 hours to stabilize, filtering to obtain a stabilized material, and placing the stabilized material in a 105 ℃ oven to bake until the water content is less than 1wt%, thus obtaining the selective debenzylation catalyst.
Evaluation of Performance
The performance of the catalysts prepared in examples 1 to 10 of the present invention was evaluated by the following method:
adding 5.0g of 4-chloro-N, N-dibenzyl aniline, 100ml of tetrahydrofuran and 0.25g of catalyst into a 250ml stainless steel high-pressure reaction kettle in sequence, replacing gas in the kettle with nitrogen and hydrogen three times successively, continuously introducing hydrogen until the pressure in the kettle is 0.25MPa, keeping the pressure in the kettle unchanged, controlling the temperature at 50 ℃ for 70min, carrying out catalytic reaction, cooling to 25 ℃ after the reaction is finished, and using N 2 H in replacement kettle 2 Three times, sample was taken for characterization by liquid chromatography and the reaction results are shown in table 1.
TABLE 1 reaction results
As can be seen from Table 1, the selective debenzylation catalyst of the present invention has a substantially complete conversion of the raw materials in catalyzing the 4-chloro-N, N-dibenzyl aniline hydrolysis debenzylation reaction, indicating that the catalyst of the present invention has a relatively high catalytic activity.
In the preparation method, when the stabilization time is 2-8 h and the mass percentage of the hydrochloric acid solution and the nitric acid solution are 10%, the selectivity of the product 4-chloro-aniline is highest and can reach 99% in the reaction, which is probably due to the influence of the reaction modification of mixed acid on the carrier active carbon on the structure and performance of the catalyst.
The foregoing description is only a preferred embodiment of the present invention, and is not intended to limit the present invention, and any simple modification, variation and equivalent structural changes of the above embodiment according to the technical matter of the present invention still fall within the scope of the technical solution of the present invention.
Claims (10)
1. A method for preparing a selective debenzylation catalyst, which is characterized by comprising the following steps:
washing the activated carbon with deionized water to be neutral, filtering, and drying until the water content is less than 1wt% to obtain the treated activated carbon;
step two, mixing a hydrochloric acid solution and a nitric acid solution to obtain a mixed acid solution;
step three, dissolving a palladium source in the mixed acid solution obtained in the step two to obtain a mixed acid solution containing active components;
step four, placing the treated active carbon in the step three in the mixed acid solution containing the active components, and stirring until the active carbon is uniformly dispersed;
and fifthly, continuously stirring the system after the dispersion in the step IV to stabilize, filtering to obtain a stabilized material, and drying the stabilized material until the water content is less than 1wt% to obtain the selective debenzylation catalyst.
2. The method for preparing a selective debenzylation catalyst according to claim 1, wherein in the first step, the particle size of the activated carbon is 200-400 mesh, and the specific surface area is more than 1000m 2 /g。
3. The method for preparing the selective debenzylation catalyst according to claim 1, wherein in the second step, the mass of the nitric acid solution is 4 times that of the hydrochloric acid solution, the mass percentage of the hydrochloric acid solution is 1% -20%, and the mass percentage of the nitric acid solution is 1% -20%.
4. The method for preparing a selective debenzylation catalyst according to claim 3, wherein the mass percentage of the hydrochloric acid solution is 3.5-10%, and the mass percentage of the nitric acid solution is 10-20%.
5. The method for preparing a selective debenzylation catalyst according to claim 4, wherein in the second step, the mass percentage of the hydrochloric acid solution is 10%, and the mass percentage of the nitric acid solution is 10%.
6. The method for preparing a selective debenzylation catalyst according to claim 5, wherein in step three, the palladium source comprises palladium chloride, palladium nitrate or potassium palladium chloride; in the third step, the mass of the mixed acid solution is 80-200 times of the mass of palladium.
7. The method for preparing a selective debenzylation catalyst according to claim 1, wherein in the fourth step, the mass of the mixed acid solution in the mixed acid solution containing the active component is 4 to 10.5 times the mass of the treated active carbon.
8. The method for preparing a selective debenzylation catalyst according to claim 7, wherein the mass of the mixed acid solution is 5 to 8 times the mass of the treated activated carbon.
9. The method for preparing a selective debenzylation catalyst according to claim 1, wherein in the fifth step, the stirring is continued for 2 to 24 hours.
10. The method for preparing a selective debenzylation catalyst according to claim 1, wherein the time for continuing stirring is 2 to 8 hours.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311834396.5A CN117816152A (en) | 2023-12-28 | 2023-12-28 | Preparation method of selective debenzylation catalyst |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311834396.5A CN117816152A (en) | 2023-12-28 | 2023-12-28 | Preparation method of selective debenzylation catalyst |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN117816152A true CN117816152A (en) | 2024-04-05 |
Family
ID=90523827
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202311834396.5A Pending CN117816152A (en) | 2023-12-28 | 2023-12-28 | Preparation method of selective debenzylation catalyst |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN117816152A (en) |
-
2023
- 2023-12-28 CN CN202311834396.5A patent/CN117816152A/en active Pending
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN113019414B (en) | Hydrogenation catalyst, preparation method and application thereof | |
| CN112387295B (en) | Nitrogen-doped carbon-loaded ruthenium monatomic catalyst as well as preparation method and application thereof | |
| CN108380208B (en) | Pd-Mg/C catalyst for preparing 2, 3-dichloropyridine by catalytic hydrogenation of 2,3, 6-trichloropyridine and preparation method thereof | |
| CN101569859A (en) | Method for preparing halogenated nitrobenzene selective hydrogenation high-activity nano-ruthenium catalyst | |
| CN107899581B (en) | Loaded on SiO2Preparation method and application of nickel catalyst on microspheres | |
| CN110801841A (en) | Catalyst for preparing 2, 2' -bipyridine by coupling synthesis of pyridine and preparation method and application thereof | |
| CN106582709B (en) | Catalyst for synthesizing aromatic primary amine by hydrogenation of aromatic nitrile and preparation method thereof | |
| CN111185214A (en) | Alumina biomass charcoal composite material, preparation method and application thereof | |
| US9108182B2 (en) | Fast filtering powder catalytic mixtures | |
| CN111545240B (en) | In-situ one-pot preparation method of Pt/Fe 3 O 4 Method and application of/C-N catalyst | |
| CN117816152A (en) | Preparation method of selective debenzylation catalyst | |
| JP2012188390A (en) | Method for producing 1,2-propanediol | |
| CN112774670A (en) | Application of rhodium monatomic catalyst in reaction for preparing m-chloroaniline through selective hydrogenation of m-chloronitrobenzene | |
| CN106964390A (en) | Benzene catalyst processed and its production and use | |
| CN112547124A (en) | Selective hydrogenation catalyst for halogenated nitrobenzene, preparation method thereof and method for catalyzing selective hydrogenation of halogenated nitrobenzene | |
| CN110538651A (en) | Platinum-carbon catalyst and preparation method thereof | |
| CN113976153B (en) | Ternary new phase Pd 3 ZnC x Preparation of catalyst and application thereof in acetylene selective hydrogenation reaction | |
| CN111569874B (en) | Active carbon-palladium-gold-gallium liquid alloy composite catalyst and preparation method and application thereof | |
| CN113083336B (en) | Magnetic iron-based catalyst and preparation method and application thereof | |
| CN108003039A (en) | A kind of method that p-nitrophenol is prepared using Sodium p-nitrophenoxide as raw material | |
| CN112237929A (en) | Catalyst for preparing olefin by dehydrogenating light alkane and method for preparing olefin | |
| CN112457199B (en) | Preparation method of m-chloroaniline | |
| CN113233985B (en) | Method for synthesizing asymmetric N-isopropyl propylamine and method for preparing catalyst | |
| CN109954511A (en) | A kind of reduction-state Nobel metal hydrogen cracking catalyst | |
| CN102302938A (en) | Catalyst for dehydrogenation and purification of bimetallic synthesis gas and preparation method thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |