CN117247347A - Preparation method of N-Boc-4-aminopiperidine - Google Patents
Preparation method of N-Boc-4-aminopiperidine Download PDFInfo
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- CN117247347A CN117247347A CN202311194933.4A CN202311194933A CN117247347A CN 117247347 A CN117247347 A CN 117247347A CN 202311194933 A CN202311194933 A CN 202311194933A CN 117247347 A CN117247347 A CN 117247347A
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- China
- Prior art keywords
- boc
- aminopiperidine
- iminopiperidine
- reaction
- piperidone
- 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.)
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- LZRDHSFPLUWYAX-UHFFFAOYSA-N tert-butyl 4-aminopiperidine-1-carboxylate Chemical compound CC(C)(C)OC(=O)N1CCC(N)CC1 LZRDHSFPLUWYAX-UHFFFAOYSA-N 0.000 title claims abstract description 27
- 238000002360 preparation method Methods 0.000 title claims abstract description 17
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 claims abstract description 28
- KWAXYFMAMGOWOO-UHFFFAOYSA-N tert-butyl 4-iminopiperidine-1-carboxylate Chemical compound CC(C)(C)OC(=O)N1CCC(=N)CC1 KWAXYFMAMGOWOO-UHFFFAOYSA-N 0.000 claims abstract description 25
- ROUYFJUVMYHXFJ-UHFFFAOYSA-N tert-butyl 4-oxopiperidine-1-carboxylate Chemical compound CC(C)(C)OC(=O)N1CCC(=O)CC1 ROUYFJUVMYHXFJ-UHFFFAOYSA-N 0.000 claims abstract description 20
- 238000005984 hydrogenation reaction Methods 0.000 claims abstract description 18
- 239000003054 catalyst Substances 0.000 claims abstract description 13
- 238000006722 reduction reaction Methods 0.000 claims abstract description 12
- 238000006243 chemical reaction Methods 0.000 claims description 28
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 claims description 27
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims description 16
- UKVIEHSSVKSQBA-UHFFFAOYSA-N methane;palladium Chemical compound C.[Pd] UKVIEHSSVKSQBA-UHFFFAOYSA-N 0.000 claims description 13
- 238000000034 method Methods 0.000 claims description 11
- 238000001914 filtration Methods 0.000 claims description 7
- 229910021529 ammonia Inorganic materials 0.000 claims description 5
- 230000035484 reaction time Effects 0.000 claims description 3
- 238000004519 manufacturing process Methods 0.000 claims description 2
- 239000002699 waste material Substances 0.000 abstract description 7
- 230000007613 environmental effect Effects 0.000 abstract description 2
- 150000001875 compounds Chemical class 0.000 description 6
- 239000002994 raw material Substances 0.000 description 6
- 238000002386 leaching Methods 0.000 description 5
- 239000000047 product Substances 0.000 description 5
- 239000007787 solid Substances 0.000 description 5
- HEDRZPFGACZZDS-MICDWDOJSA-N Trichloro(2H)methane Chemical compound [2H]C(Cl)(Cl)Cl HEDRZPFGACZZDS-MICDWDOJSA-N 0.000 description 4
- 239000002904 solvent Substances 0.000 description 4
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 3
- 238000010438 heat treatment Methods 0.000 description 3
- 229910052751 metal Inorganic materials 0.000 description 3
- 239000002184 metal Substances 0.000 description 3
- 239000012452 mother liquor Substances 0.000 description 3
- 238000003786 synthesis reaction Methods 0.000 description 3
- 238000005160 1H NMR spectroscopy Methods 0.000 description 2
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- 238000005481 NMR spectroscopy Methods 0.000 description 2
- KDLHZDBZIXYQEI-UHFFFAOYSA-N Palladium Chemical compound [Pd] KDLHZDBZIXYQEI-UHFFFAOYSA-N 0.000 description 2
- 230000006978 adaptation Effects 0.000 description 2
- CBHOOMGKXCMKIR-UHFFFAOYSA-N azane;methanol Chemical compound N.OC CBHOOMGKXCMKIR-UHFFFAOYSA-N 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 2
- 239000006227 byproduct Substances 0.000 description 2
- 229910001873 dinitrogen Inorganic materials 0.000 description 2
- 238000001035 drying Methods 0.000 description 2
- 238000002474 experimental method Methods 0.000 description 2
- 239000005457 ice water Substances 0.000 description 2
- 239000007788 liquid Substances 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 239000000376 reactant Substances 0.000 description 2
- 238000004064 recycling Methods 0.000 description 2
- 206010058467 Lung neoplasm malignant Diseases 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 238000002425 crystallisation Methods 0.000 description 1
- 230000008025 crystallization Effects 0.000 description 1
- 229940079593 drug Drugs 0.000 description 1
- 239000003814 drug Substances 0.000 description 1
- 238000001704 evaporation Methods 0.000 description 1
- 230000008020 evaporation Effects 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 238000009776 industrial production Methods 0.000 description 1
- 201000005202 lung cancer Diseases 0.000 description 1
- 208000020816 lung neoplasm Diseases 0.000 description 1
- 230000001737 promoting effect Effects 0.000 description 1
- 239000007858 starting material Substances 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 238000001308 synthesis method Methods 0.000 description 1
- 238000010189 synthetic method Methods 0.000 description 1
- LDLQTMSUZKHEHY-UHFFFAOYSA-N tert-butyl 4-hydroxyiminopiperidine-1-carboxylate Chemical compound CC(C)(C)OC(=O)N1CCC(=NO)CC1 LDLQTMSUZKHEHY-UHFFFAOYSA-N 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D211/00—Heterocyclic compounds containing hydrogenated pyridine rings, not condensed with other rings
- C07D211/04—Heterocyclic compounds containing hydrogenated pyridine rings, not condensed with other rings with only hydrogen or carbon atoms directly attached to the ring nitrogen atom
- C07D211/06—Heterocyclic compounds containing hydrogenated pyridine rings, not condensed with other rings with only hydrogen or carbon atoms directly attached to the ring nitrogen atom having no double bonds between ring members or between ring members and non-ring members
- C07D211/36—Heterocyclic compounds containing hydrogenated pyridine rings, not condensed with other rings with only hydrogen or carbon atoms directly attached to the ring nitrogen atom having no double bonds between ring members or between ring members and non-ring members with hetero atoms or with carbon atoms having three bonds to hetero atoms with at the most one bond to halogen, e.g. ester or nitrile radicals, directly attached to ring carbon atoms
- C07D211/56—Nitrogen atoms
- C07D211/58—Nitrogen atoms attached in position 4
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Hydrogenated Pyridines (AREA)
Abstract
The invention provides a preparation method of N-Boc-4-aminopiperidine, which comprises the following steps: s1, enabling N-Boc-4-iminopiperidine to undergo hydrogenation reduction reaction under the action of a catalyst to generate N-Boc-4-aminopiperidine. Further, the preparation method also comprises the following steps: s0, reacting N-Boc-4-piperidone with ammonia gas to generate the N-Boc-4-iminopiperidine. According to the preparation method, the operation and the post-treatment are simple; the catalyst has high repeatability; reduces the generation of three wastes and reduces the environmental protection pressure.
Description
Technical Field
The invention relates to the technical field of chemical synthesis, in particular to a preparation method of N-Boc-4-aminopiperidine.
Background
N-Boc-4-aminopiperidine (also known as N-Boc-4-aminopiperidine) is a useful intermediate in organic synthesis, widely used in substitution reactions, and recently used in the synthesis of targeted drugs for the treatment of lung cancer.
At present, the synthesis method of the compound mainly takes 4- (hydroxyimino) piperidine-1-carboxylic acid tert-butyl ester as a raw material to prepare N-Boc-4-aminopiperidine. However, the method has the problems of raw material availability, high price, great generation of three wastes and the like.
Therefore, a synthetic method with easily available raw materials, convenient operation, less three wastes and high overall yield needs to be developed.
Disclosure of Invention
In view of the above, the present invention aims to provide a preparation method which has high safety, simple treatment operation and suitability for industrial production.
In order to solve the technical problems, the invention adopts the following technical scheme:
the preparation method of the N-Boc-4-aminopiperidine comprises the following steps:
s1, enabling N-Boc-4-iminopiperidine to undergo hydrogenation reduction reaction under the action of a catalyst to generate N-Boc-4-aminopiperidine.
Further, the preparation method further comprises the following steps:
s0, reacting N-Boc-4-piperidone with ammonia gas to generate the N-Boc-4-iminopiperidine.
Further, the step S0 includes:
N-Boc-4-piperidone was added to a methanol solution of ammonia gas to react N-Boc-4-piperidone with ammonia gas.
Further, the concentration of the methanol solution of the ammonia gas is 1-3 mol/L.
Further, the N-Boc-4-piperidone: the molar ratio of ammonia is 1 (1-1.5).
Further, in the step S0, the reaction temperature is 10-20 ℃ and the reaction time is 2-6 hours.
Further, the step S0 further includes:
after the reaction is finished, concentrating is carried out to obtain the N-Boc-4-iminopiperidine.
Further, the step S1 includes:
adding N-Boc-4-iminopiperidine into ethanol, and carrying out hydrogenation reduction reaction by using palladium-carbon as a catalyst under the action of hydrogenation pressurization to obtain the N-Boc-4-aminopiperidine.
Further, in the step S1, the reaction temperature is 50-60 ℃ and the pressure is 4.0-5.0MPa.
Further, the step S1 further includes:
after the reaction is completed, filtering and concentrating are carried out to obtain the N-Boc-4-aminopiperidine.
The technical scheme of the invention has at least one of the following beneficial effects:
according to the preparation method, the operation and the post-treatment are simple; the catalyst has high repeatability; reduces the generation of three wastes and reduces the environmental protection pressure.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present invention more clear, the technical solutions of the present invention will be clearly and completely described below in connection with the embodiments of the present invention. It will be apparent that the described embodiments are some, but not all, embodiments of the invention. All other embodiments, which are obtained by a person skilled in the art based on the described embodiments of the invention, fall within the scope of protection of the invention.
Next, a method for preparing N-Boc-4-aminopiperidine according to an embodiment of the present invention will be described in detail first.
The preparation method of the N-Boc-4-aminopiperidine comprises the following steps:
s1, enabling N-Boc-4-iminopiperidine to undergo hydrogenation reduction reaction under the action of a catalyst to generate N-Boc-4-aminopiperidine.
Namely, N-Boc-4-iminopiperidine is taken as a raw material, and is subjected to hydrogenation reduction reaction under the action of a catalyst to obtain the target product N-Boc-4-aminopiperidine.
Wherein, the N-Boc-4-iminopiperidine used as the raw material can be commercial N-Boc-4-iminopiperidine sold in the market or can be prepared by itself.
Specifically, in some embodiments of the present invention, the preparation method further includes the steps of:
s0, reacting N-Boc-4-piperidone with ammonia gas to generate the N-Boc-4-iminopiperidine.
That is, in this example, N-Boc-4-piperidone was used as an actual starting material, which was first reacted with ammonia gas to produce N-Boc-4-iminopiperidine, and then further subjected to hydrogenation reduction to produce N-Boc-4-aminopiperidine.
Next, the steps S0 and S1 are described step by step with reference to examples.
First, the reaction step of N-Boc-4-piperidone with ammonia gas, which is step S0, will be described.
The reaction formula is shown as the following formula (1):
further, the step S0 includes:
N-Boc-4-piperidone was added to a methanol solution of ammonia gas to react N-Boc-4-piperidone with ammonia gas.
That is, the reaction is carried out in a methanol environment. The N-Boc-4-piperidone and ammonia have good solubility in methanol, which is beneficial to promoting the reaction.
Further, the concentration of the methanol solution of ammonia gas is 1 to 3mol/L, preferably, 2mol/L. The reaction of ammonia and N-Boc-4-piperidone is a parallel reaction, and a proper concentration can maximize the conversion of the target compound.
Further, the N-Boc-4-piperidone: the molar ratio of ammonia is 1 (1-1.5), preferably 1:1.2. that is, the use of a slight excess of ammonia gas is advantageous to increase the utilization rate of N-Boc-4-piperidone and the yield of the step, to increase the conversion rate, and the remainder of ammonia gas can be recovered by heating and evaporation, without causing waste of raw materials.
Further, in the step S0, the reaction temperature is 10-20 ℃ and the reaction time is 2-6 hours. The reaction condition is mild, the operability is strong, and the method is suitable for industrial mass production.
Further, the step S0 further includes:
after the reaction is finished, concentrating is carried out to obtain the N-Boc-4-iminopiperidine.
That is, when the concentration is directly carried out after the completion of the reaction, the excess ammonia gas and methanol as a solvent are volatilized (this part can be recovered and reused), thereby crystallizing N-Boc-4-iminopiperidine. The N-Boc-4-iminopiperidine obtained by the crystallization can be directly used in the next step without unnecessary byproducts and the like, and three wastes are basically not generated.
After obtaining N-Boc-4-iminopiperidine, it is then subjected to hydrogenation reduction to prepare the target product N-Boc-4-aminopiperidine, step S1.
In some embodiments of the invention, the step S1 includes:
adding N-Boc-4-iminopiperidine into ethanol, and carrying out hydrogenation reduction reaction by using palladium-carbon as a catalyst under the action of hydrogenation pressurization to obtain the N-Boc-4-aminopiperidine.
That is, in an ethanol solution, hydrogenation reduction is performed with palladium on carbon as a catalyst.
Specifically, palladium carbon may be used with a metal content of 5%, palladium carbon with a metal content of 10%, or the like, and among them, palladium carbon with a metal content of 5% is preferably used.
In some embodiments of the invention, in the step S1, the reaction temperature is 50-60 ℃ and the pressure is 4.0-5.0MPa. That is, the hydrogenation is carried out at a temperature of 50 to 60℃and the hydrogen is added in such an amount that the overall pressure is 4.0 to 5.0MPa.
Further, the step S1 may further include:
after the reaction is completed, filtering and concentrating are carried out to obtain the N-Boc-4-aminopiperidine.
That is, after the reaction is finished, the solid part, namely palladium carbon, is removed by filtration to serve as a catalyst, and the catalyst can be repeatedly reused through leaching. In addition, the mother liquor obtained by filtration is concentrated to remove the solvent, thus obtaining the target product N-Boc-4-aminopiperidine. As is clear from the above, unnecessary by-product impurities and the like are not introduced in the hydrogenation reduction reaction, and the post-treatment operation after the completion of the reaction is simple and three wastes are less.
The present invention will be described in further detail with reference to specific examples so that those skilled in the art can better understand the technical aspects of the present invention.
Example 1:
(1) Preparation of the Compound N-Boc-4-iminopiperidine
A250 mL reaction flask was charged with ammonia methanol (2M, 100mL,0.20mol,1.2 eq), cooled to 10deg.C in an ice-water bath, and N-Boc-4-piperidone (33.21 g,0.17mol,1.0 eq) was added in portions at a temperature of 10-20deg.C. The reaction was continued for 4 hours at a temperature of 35℃and the solvent was concentrated in a water bath to give 31.6g of a pale yellow liquid, and the yield was 95.76%.
(2) Preparation of the Compound N-Boc-4-aminopiperidine
N-Boc-4-iminopiperidine (31.6 g,0.16mol,1.0 eq), 5% palladium carbon (1.5 g wet weight), ethanol (200 mL), nitrogen gas replacement for three times, heating to 50-60 ℃, starting to introduce hydrogen gas, keeping the pressure at 4.0-5.0MPa, starting to react, keeping the temperature and the pressure for 1 hour when the pressure is unchanged, filtering, leaching the solid palladium carbon with ethanol once (recycling palladium carbon for reuse until the next batch of hydrogenation), merging mother liquor and leaching liquor, concentrating and drying to obtain white solid 29.0g, and the yield is 90.63%.
The nuclear magnetic resonance experiment is carried out on the reactant to confirm the structure of the product, and the data are as follows:
1H NMR(CDCl3):4.04(2H,s),2.86-2.74(3H,m),1.81-1.77(2H,m),
1.68-1.66 (2H, s), 1.49 (9H, s), 1.30-1.20 (2H, m) and the structure are matched.
Example 2:
(1) Preparation of the Compound N-Boc-4-iminopiperidine
A250 mL reaction flask was charged with ammonia methanol (2M, 150mL,0.30mol,1.2 eq), cooled to 5℃in an ice-water bath, and N-Boc-4-piperidone (46.82 g,0.25mol,1.0 eq) was added in portions, the temperature was controlled at 10-20 ℃. The reaction was incubated for 4 hours, and the solvent was concentrated in a 35℃water bath to give 46.9g of a pale yellow liquid, with a yield of 94.75%.
(2) Preparation of the Compound N-Boc-4-aminopiperidine
N-Boc-4-iminopiperidine (46.9 g,0.16mol,1.0 eq), 5% palladium carbon (2.3 g wet weight), ethanol (300 mL), nitrogen gas replacement for three times, heating to 50-60 ℃, starting to introduce hydrogen gas, keeping the pressure at 4.0-5.0MPa, starting to react, keeping the temperature and the pressure for 1 hour when the pressure is unchanged, filtering, leaching the solid palladium carbon with ethanol once (recycling palladium carbon for reuse until the next batch of hydrogenation), merging mother liquor and leaching liquor, concentrating and drying to obtain white solid 41.7g, wherein the yield is 86.88%.
The nuclear magnetic resonance experiment is carried out on the reactant to confirm the structure of the product, and the data are as follows:
1H NMR(CDCl3):4.04(2H,s),2.86-2.74(3H,m),1.81-1.77(2H,m),
1.68-1.66 (2H, s), 1.49 (9H, s), 1.30-1.20 (2H, m) and the structure are matched.
While the foregoing is directed to the preferred embodiments of the present invention, it will be appreciated by those skilled in the art that various modifications and adaptations can be made without departing from the principles of the present invention, and such modifications and adaptations are intended to be comprehended within the scope of the present invention.
Claims (10)
1. The preparation method of the N-Boc-4-aminopiperidine is characterized by comprising the following steps of:
s1, enabling N-Boc-4-iminopiperidine to undergo hydrogenation reduction reaction under the action of a catalyst to generate N-Boc-4-aminopiperidine.
2. The method of manufacturing according to claim 1, further comprising the step of:
s0, reacting N-Boc-4-piperidone with ammonia gas to generate the N-Boc-4-iminopiperidine.
3. The method according to claim 2, wherein the step S0 comprises:
N-Boc-4-piperidone was added to a methanol solution of ammonia gas to react N-Boc-4-piperidone with ammonia gas.
4. The method according to claim 3, wherein the concentration of the methanol solution of ammonia gas is 1 to 3mol/L.
5. A process according to claim 3, wherein the N-Boc-4-piperidone: the molar ratio of ammonia is 1 (1-1.5).
6. The method according to claim 3, wherein in the step S0, the reaction temperature is 10 to 20℃and the reaction time is 2 to 6 hours.
7. The method according to claim 3, wherein the step S0 further comprises:
after the reaction is finished, concentrating is carried out to obtain the N-Boc-4-iminopiperidine.
8. The method according to claim 1, wherein the step S1 comprises:
adding N-Boc-4-iminopiperidine into ethanol, and carrying out hydrogenation reduction reaction by using palladium-carbon as a catalyst under the action of hydrogenation pressurization to obtain the N-Boc-4-aminopiperidine.
9. The method according to claim 8, wherein in the step S1, the reaction temperature is 50-60℃and the pressure is 4.0-5.0MPa.
10. The method according to claim 8, wherein the step S1 further comprises:
after the reaction is completed, filtering and concentrating are carried out to obtain the N-Boc-4-aminopiperidine.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311194933.4A CN117247347A (en) | 2023-09-15 | 2023-09-15 | Preparation method of N-Boc-4-aminopiperidine |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311194933.4A CN117247347A (en) | 2023-09-15 | 2023-09-15 | Preparation method of N-Boc-4-aminopiperidine |
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| Publication Number | Publication Date |
|---|---|
| CN117247347A true CN117247347A (en) | 2023-12-19 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
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| CN202311194933.4A Pending CN117247347A (en) | 2023-09-15 | 2023-09-15 | Preparation method of N-Boc-4-aminopiperidine |
Country Status (1)
| Country | Link |
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| CN (1) | CN117247347A (en) |
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2023
- 2023-09-15 CN CN202311194933.4A patent/CN117247347A/en active Pending
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