CN112390721A - Synthetic method of 3,3 '-diamino-4, 4' dihydroxybiphenyl hydrochloride - Google Patents
Synthetic method of 3,3 '-diamino-4, 4' dihydroxybiphenyl hydrochloride Download PDFInfo
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- -1 3,3 '-diamino-4, 4' dihydroxybiphenyl hydrochloride Chemical compound 0.000 title claims abstract description 48
- 238000010189 synthetic method Methods 0.000 title description 2
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 claims abstract description 110
- KDLHZDBZIXYQEI-UHFFFAOYSA-N Palladium Chemical compound [Pd] KDLHZDBZIXYQEI-UHFFFAOYSA-N 0.000 claims abstract description 64
- 239000001257 hydrogen Substances 0.000 claims abstract description 54
- 229910052739 hydrogen Inorganic materials 0.000 claims abstract description 54
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 claims abstract description 53
- 239000003054 catalyst Substances 0.000 claims abstract description 50
- 238000006243 chemical reaction Methods 0.000 claims abstract description 42
- NTXCSKZBHUKPQU-UHFFFAOYSA-N 4-(4-hydroxy-3-nitrophenyl)-2-nitrophenol Chemical group C1=C([N+]([O-])=O)C(O)=CC=C1C1=CC=C(O)C([N+]([O-])=O)=C1 NTXCSKZBHUKPQU-UHFFFAOYSA-N 0.000 claims abstract description 39
- 238000003756 stirring Methods 0.000 claims abstract description 35
- 238000000034 method Methods 0.000 claims abstract description 31
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims abstract description 26
- KZLDGFZCFRXUIB-UHFFFAOYSA-N 2-amino-4-(3-amino-4-hydroxyphenyl)phenol Chemical group C1=C(O)C(N)=CC(C=2C=C(N)C(O)=CC=2)=C1 KZLDGFZCFRXUIB-UHFFFAOYSA-N 0.000 claims abstract description 22
- 238000001914 filtration Methods 0.000 claims abstract description 21
- 230000002194 synthesizing effect Effects 0.000 claims abstract description 15
- TXUICONDJPYNPY-UHFFFAOYSA-N (1,10,13-trimethyl-3-oxo-4,5,6,7,8,9,11,12,14,15,16,17-dodecahydrocyclopenta[a]phenanthren-17-yl) heptanoate Chemical compound C1CC2CC(=O)C=C(C)C2(C)C2C1C1CCC(OC(=O)CCCCCC)C1(C)CC2 TXUICONDJPYNPY-UHFFFAOYSA-N 0.000 claims abstract description 9
- 229910021626 Tin(II) chloride Inorganic materials 0.000 claims abstract description 9
- 239000001119 stannous chloride Substances 0.000 claims abstract description 9
- 235000011150 stannous chloride Nutrition 0.000 claims abstract description 9
- 239000012295 chemical reaction liquid Substances 0.000 claims abstract description 7
- 239000007788 liquid Substances 0.000 claims abstract description 6
- 238000002156 mixing Methods 0.000 claims abstract description 3
- 239000000243 solution Substances 0.000 claims description 45
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims description 36
- 239000007789 gas Substances 0.000 claims description 34
- 239000012065 filter cake Substances 0.000 claims description 18
- 229910052757 nitrogen Inorganic materials 0.000 claims description 18
- 238000000967 suction filtration Methods 0.000 claims description 18
- 238000001291 vacuum drying Methods 0.000 claims description 18
- 238000011068 loading method Methods 0.000 claims description 2
- 239000011259 mixed solution Substances 0.000 claims description 2
- 239000006227 byproduct Substances 0.000 abstract description 5
- 231100000331 toxic Toxicity 0.000 abstract description 5
- 230000002588 toxic effect Effects 0.000 abstract description 5
- 238000004128 high performance liquid chromatography Methods 0.000 description 17
- 238000005984 hydrogenation reaction Methods 0.000 description 17
- 238000001816 cooling Methods 0.000 description 16
- 238000007599 discharging Methods 0.000 description 16
- 238000010438 heat treatment Methods 0.000 description 16
- 238000010010 raising Methods 0.000 description 16
- 239000012265 solid product Substances 0.000 description 16
- 230000001502 supplementing effect Effects 0.000 description 16
- AXZWODMDQAVCJE-UHFFFAOYSA-L tin(II) chloride (anhydrous) Chemical compound [Cl-].[Cl-].[Sn+2] AXZWODMDQAVCJE-UHFFFAOYSA-L 0.000 description 16
- NWZSZGALRFJKBT-KNIFDHDWSA-N (2s)-2,6-diaminohexanoic acid;(2s)-2-hydroxybutanedioic acid Chemical compound OC(=O)[C@@H](O)CC(O)=O.NCCCC[C@H](N)C(O)=O NWZSZGALRFJKBT-KNIFDHDWSA-N 0.000 description 4
- 230000015572 biosynthetic process Effects 0.000 description 4
- IKDUDTNKRLTJSI-UHFFFAOYSA-N hydrazine monohydrate Substances O.NN IKDUDTNKRLTJSI-UHFFFAOYSA-N 0.000 description 4
- 239000002994 raw material Substances 0.000 description 4
- 238000003786 synthesis reaction Methods 0.000 description 4
- WEVYAHXRMPXWCK-UHFFFAOYSA-N Acetonitrile Chemical compound CC#N WEVYAHXRMPXWCK-UHFFFAOYSA-N 0.000 description 3
- IAZDPXIOMUYVGZ-UHFFFAOYSA-N Dimethylsulphoxide Chemical compound CS(C)=O IAZDPXIOMUYVGZ-UHFFFAOYSA-N 0.000 description 3
- 235000003891 ferrous sulphate Nutrition 0.000 description 3
- 239000011790 ferrous sulphate Substances 0.000 description 3
- BAUYGSIQEAFULO-UHFFFAOYSA-L iron(2+) sulfate (anhydrous) Chemical compound [Fe+2].[O-]S([O-])(=O)=O BAUYGSIQEAFULO-UHFFFAOYSA-L 0.000 description 3
- 229910000359 iron(II) sulfate Inorganic materials 0.000 description 3
- 239000000047 product Substances 0.000 description 3
- 125000004429 atom Chemical group 0.000 description 2
- 239000003638 chemical reducing agent Substances 0.000 description 2
- 125000002887 hydroxy group Chemical group [H]O* 0.000 description 2
- 239000000178 monomer Substances 0.000 description 2
- 230000035484 reaction time Effects 0.000 description 2
- 238000005160 1H NMR spectroscopy Methods 0.000 description 1
- ICXAPFWGVRTEKV-UHFFFAOYSA-N 2-[4-(1,3-benzoxazol-2-yl)phenyl]-1,3-benzoxazole Chemical class C1=CC=C2OC(C3=CC=C(C=C3)C=3OC4=CC=CC=C4N=3)=NC2=C1 ICXAPFWGVRTEKV-UHFFFAOYSA-N 0.000 description 1
- 238000005033 Fourier transform infrared spectroscopy Methods 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- 239000000853 adhesive Substances 0.000 description 1
- 230000001070 adhesive effect Effects 0.000 description 1
- 239000011825 aerospace material Substances 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000003889 chemical engineering Methods 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000002330 electrospray ionisation mass spectrometry Methods 0.000 description 1
- 238000005265 energy consumption Methods 0.000 description 1
- 235000019441 ethanol Nutrition 0.000 description 1
- 239000000835 fiber Substances 0.000 description 1
- 239000003779 heat-resistant material Substances 0.000 description 1
- 150000002431 hydrogen Chemical class 0.000 description 1
- 238000009776 industrial production Methods 0.000 description 1
- 231100000252 nontoxic Toxicity 0.000 description 1
- 230000003000 nontoxic effect Effects 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 229920000642 polymer Polymers 0.000 description 1
- 238000006116 polymerization reaction Methods 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 239000011541 reaction mixture Substances 0.000 description 1
- 238000001308 synthesis method Methods 0.000 description 1
- 239000004753 textile Substances 0.000 description 1
- 231100000419 toxicity Toxicity 0.000 description 1
- 230000001988 toxicity Effects 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C213/00—Preparation of compounds containing amino and hydroxy, amino and etherified hydroxy or amino and esterified hydroxy groups bound to the same carbon skeleton
- C07C213/02—Preparation of compounds containing amino and hydroxy, amino and etherified hydroxy or amino and esterified hydroxy groups bound to the same carbon skeleton by reactions involving the formation of amino groups from compounds containing hydroxy groups or etherified or esterified hydroxy groups
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- Chemical Kinetics & Catalysis (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
A method of synthesizing 3,3 '-diamino-4, 4' dihydroxybiphenyl hydrochloride, the method comprising the steps of: (1) adding 3,3 '-dinitro-4, 4' dihydroxybiphenyl, absolute ethyl alcohol and a Pd/C catalyst into an autoclave, exhausting air in the autoclave, and stirring for 7-10 hours at 40-60 ℃ and under the condition that the hydrogen pressure is 0.4-0.8 MPa to obtain a reaction liquid A containing 3,3 '-diamino-4, 4' dihydroxybiphenyl; (2) and mixing the reaction liquid A with hydrochloric acid solution of stannous chloride, filtering to remove a Pd/C catalyst, adding concentrated hydrochloric acid to adjust the pH value to 1-3, standing and crystallizing to obtain mixed liquid B, and carrying out aftertreatment on the mixed liquid B to obtain 3,3 '-diamino-4, 4' dihydroxy biphenyl hydrochloride. The method has the advantages of easily controlled reaction process parameters, no generation of highly toxic byproducts, high atom utilization rate, high yield, high purity and simple post-treatment.
Description
(I) technical field
The invention relates to a method for synthesizing 3,3 '-diamino-4, 4' -dihydroxybiphenyl hydrochloride.
(II) background of the invention
The PBO monomer 3,3 '-diamino-4, 4' dihydroxybiphenyl hydrochloride shown in formula (1) provides raw materials for preparing hydroxyl modified poly-p-phenylene benzodioxazole polymer by polymerization, and can also be used as raw materials for preparing heat-resistant materials, adhesives and aerospace materials (Dongning, Yuxia, Guosheng. PBO fiber, Chengdu textile high specialty school bulletin, 2016,32(2): 182-.
At present, the main synthesis method for synthesizing 3,3 '-diamino-4, 4' dihydroxybiphenyl hydrochloride shown in formula (1): the 3,3 '-dinitro-4, 4' -dihydroxybiphenyl hydrochloride is used as a raw material, and is synthesized by a hydrazine hydrate reduction method, although the method has simple operation and short reaction time, the method has the defects of large hydrazine hydrate consumption, large toxicity of byproducts, large pollution caused by ferrous sulfate serving as a catalyst and the like, so the method has poor reaction safety and poor industrial production capacity (Wu Chun, Chang Lu, Chen Di Chao and the like, synthesis of the hydroxyl modified poly-p-phenylene benzobisoxazole monomer 3,3 '-diamino-4, 4' -dihydroxybiphenyl hydrochloride, chemical engineering progress 2020,39(2):696 acid 701.).
In view of the above-mentioned circumstances for synthesizing 3,3 '-diamino-4, 4' dihydroxybiphenyl hydrochloride, we have searched for a new method for industrially easily realizing more rational synthesis of 3,3 '-diamino-4, 4' dihydroxybiphenyl hydrochloride.
(three) summary of invention
The invention aims to provide a method for preparing high-purity 3,3 '-diamino-4, 4' dihydroxydiphenyl hydrochloride, which has the advantages of easily available raw materials, short synthesis steps, high reaction selectivity, no generation of highly toxic byproducts, short reaction time, high atom utilization rate, simple post-treatment and high yield, and is industrially feasible.
In order to solve the problems, the invention adopts the following technical scheme:
a method of synthesizing 3,3 '-diamino-4, 4' dihydroxybiphenyl hydrochloride, the method comprising the steps of:
(1) adding 3,3 '-dinitro-4, 4' dihydroxybiphenyl, absolute ethyl alcohol and a Pd/C catalyst into an autoclave, exhausting air in the autoclave, and stirring for 7-10 hours at 40-60 ℃ and under the condition that the hydrogen pressure is 0.4-0.8 MPa to obtain a reaction liquid A containing 3,3 '-diamino-4, 4' dihydroxybiphenyl; the mass ratio of the 3,3 '-dinitro-4, 4' -dihydroxybiphenyl to the Pd/C catalyst is 1: 0.05 to 0.2; the volume of the absolute ethyl alcohol is 100-150 mL/g based on the mass of the 3,3 '-dinitro-4, 4' -dihydroxybiphenyl;
(2) mixing the reaction liquid A with hydrochloric acid solution of stannous chloride, filtering to remove a Pd/C catalyst, adding concentrated hydrochloric acid to adjust the pH value to 1-3, standing and crystallizing to obtain mixed liquid B, and carrying out aftertreatment on the mixed liquid B to obtain 3,3 '-diamino-4, 4' dihydroxy biphenyl hydrochloride; the mass ratio of the stannous chloride to the 3,3 '-dinitro-4, 4' -dihydroxy biphenyl is 1: 8-10, wherein the volume of the hydrochloric acid solution is 10-15 mL/g based on the mass of 3,3 '-dinitro-4, 4' -dihydroxybiphenyl, and the concentration of hydrochloric acid in the hydrochloric acid solution is 4-6 wt%. The concentration of the concentrated hydrochloric acid is 36 wt%.
The reason why the Pd/C catalyst is removed by filtering after the reaction liquid A is mixed with hydrochloric acid solution of stannous chloride is that the reduction product 3,3 '-diamino-4, 4' dihydroxybiphenyl is partially precipitated in ethanol solution, hydrochloric acid solution is needed to be added to dissolve the 3,3 '-diamino-4, 4' dihydroxybiphenyl, and then the Pd/C catalyst is removed by filtering, so that the loss of the 3,3 '-diamino-4, 4' dihydroxybiphenyl is prevented. In addition, the reducibility of stannous chloride prevents oxidation of the 3,3 '-diamino-4, 4' dihydroxybiphenylamino group.
Preferably, the method for exhausting the air in the autoclave in the step (1) comprises the following steps: the gas in the kettle is replaced by nitrogen for three times, and then replaced by hydrogen for three times, wherein the pressure in each time is 0.6 MPa.
Preferably, the loading of Pd in the Pd/C catalyst is 5 wt%.
Preferably, the reaction conditions in the step (1) are 40-50 ℃ and 0.4-0.6 MPa for 8-9 h.
Preferably, the mass ratio of the 3,3 '-dinitro-4, 4' dihydroxybiphenyl and the Pd/C catalyst in step (1) is 1: 0.1 to 0.2, and more preferably 1: 0.1 to 0.15. The Pd/C catalyst is commercially available.
Preferably, the volume of the absolute ethyl alcohol in the step (1) is 125mL/g based on the mass of the 3,3 '-dinitro-4, 4' dihydroxybiphenyl.
Particularly preferably, the standing time in the step (2) is 12 hours. The reaction mixture was allowed to stand for 12 hours to precipitate as much crystals of 3,3 '-diamino-4, 4' -dihydroxybiphenyl hydrochloride as possible.
Still more preferably, the mass ratio of the stannous chloride to the 3,3 '-dinitro-4, 4' dihydroxybiphenyl is 1: 10, the volume of the hydrochloric acid solution is 12.5mL/g based on the mass of the 3,3 '-dinitro-4, 4' dihydroxybiphenyl, and the hydrochloric acid concentration in the hydrochloric acid solution is 5 wt%.
Preferably, concentrated hydrochloric acid is added in step (2) to adjust the pH to 2.
Further, the post-treatment process comprises the following steps: and carrying out suction filtration on the obtained mixed solution B, and carrying out vacuum drying on a filter cake to obtain the 3,3 '-diamino-4, 4' dihydroxybiphenyl hydrochloride.
Compared with the prior art, the invention has the following beneficial effects: the hydrogenation reduction method provided by the invention has the advantages of easily controlled reaction process parameters, clean and nontoxic reducing agent hydrogen, no generation of highly toxic byproducts, high atom utilization rate, high yield, high purity and simple post-treatment. The traditional hydrazine hydrate reduction method not only uses the reducing agent hydrazine hydrate which is toxic and has larger dosage, but also generates toxic byproducts in the reaction process, and the pollution of ferrous sulfate which is used as a catalyst for the reaction is larger. Compared with ferrous sulfate, the Pd/C catalyst used in the reaction is cleaner and more environment-friendly, and the post-treatment is more convenient; the reaction temperature is lower, the energy consumption is less, and the industrial feasibility is higher.
(IV) detailed description of the preferred embodiments
The present invention is illustrated in more detail by examples, but the scope of the present invention is not limited by the examples.
Example 1
Adding 4g of 3,3 '-dinitro-4, 4' dihydroxybiphenyl, 500mL of absolute ethyl alcohol and 0.4g of Pd/C (5%) as a catalyst into a 2000mL autoclave with a stirring and a built-in condensing tube, replacing gas in the autoclave with nitrogen for three times, then replacing gas in the autoclave with hydrogen for three times, wherein the pressure in each time is 0.6MPa, then maintaining the pressure of the hydrogen in the autoclave at 0.6MPa, starting stirring, heating, raising the temperature, controlling the reaction temperature at 50 ℃, and carrying out hydrogenation reaction. Reacting for 8 hours, supplementing hydrogen for multiple times during the reaction, cooling to 25 ℃, releasing pressure, discharging, dissolving the obtained 3,3 '-diamino-4, 4' dihydroxybiphenyl solution in 50mL of 5 wt% hydrochloric acid solution containing 0.4g of anhydrous stannous chloride, filtering out the catalyst, adding 36 wt% concentrated hydrochloric acid to adjust the pH value to 2, standing for 12 hours, carrying out suction filtration, and carrying out vacuum drying on a filter cake to obtain a white solid product 3,3 '-diamino-4, 4' dihydroxybiphenyl hydrochloride 3.07g, wherein the HPLC analysis mass fraction is 98.89%, and the yield is 72.48%.
FT-IR(KBr，cm-1)：3351.1(s)，3255.4(s)，2988.3(s)，1614.0(s)， 1080.2(s)。
1H-NMR(DMSO，δ，ppm)：11.06(2H，s，OH)，10.23(4H，s， NH2)。
ESI-MS：[M+H]+＝290.1
HPLC analysis conditions for 3,3 '-dinitro-4, 4' dihydroxybiphenyl and 3,3 '-diamino-4, 4' dihydroxybiphenyl hydrochloride are as follows: ODS C18Column, 6.0 × 150mm, mobile phase: acetonitrile/water 40/60(V/V), detection wavelength 254nm, flow rate 1.0 mL/min.
Examples 2 to 13
Examples 2 to 13 the same procedure as in example 1 was used, and different parameters were used in accordance with the parameter ranges of the present invention, and it was found that the purity of 3,3 '-dinitro-4, 4' dihydroxybiphenyl and 3,3 '-diamino-4, 4' dihydroxybiphenyl hydrochloride obtained under these process conditions was 85% or more, and the net yield of 3,3 '-dinitro-4, 4' dihydroxybiphenyl and 3,3 '-diamino-4, 4' dihydroxybiphenyl hydrochloride products was 62% or more, and that the process was applicable to the industrial synthesis of 3,3 '-dinitro-4, 4' dihydroxybiphenyl and 3,3 '-diamino-4, 4' dihydroxybiphenyl hydrochloride.
Example 2
Adding 4g of 3,3 '-dinitro-4, 4' dihydroxybiphenyl, 500mL of absolute ethyl alcohol and 0.4g of Pd/C (5%) as a catalyst into a 2000mL autoclave with a stirring and a built-in condensing tube, replacing gas in the autoclave with nitrogen for three times, then replacing gas in the autoclave with hydrogen for three times, wherein the pressure in each time is 0.6MPa, then maintaining the pressure of the hydrogen in the autoclave at 0.6MPa, starting stirring, heating, raising the temperature, controlling the reaction temperature to be 40 ℃, and carrying out hydrogenation reaction. Reacting for 8 hours, supplementing hydrogen for multiple times during the reaction, cooling to 25 ℃, relieving pressure and discharging, dissolving the obtained 3,3 '-diamino-4, 4' dihydroxybiphenyl solution in 50mL of 5 wt% hydrochloric acid solution containing 0.4g of anhydrous stannous chloride, filtering out the catalyst, adding 36 wt% concentrated hydrochloric acid to adjust the pH value to 2, standing for 12 hours, carrying out suction filtration, and carrying out vacuum drying on a filter cake to obtain a white solid product 3,3 '-diamino-4, 4' dihydroxybiphenyl hydrochloride 3.21g, wherein the HPLC analysis mass fraction is 91.85%, and the yield is 70.39%.
Example 3
Adding 4g of 3,3 '-dinitro-4, 4' dihydroxybiphenyl, 500mL of absolute ethyl alcohol and 0.4g of Pd/C (5%) as a catalyst into a 2000mL autoclave with a stirring and a built-in condensing tube, replacing the gas in the autoclave with nitrogen for three times, then replacing the gas in the autoclave with hydrogen for three times, wherein the pressure in each time is 0.6MPa, then maintaining the pressure of the hydrogen in the autoclave at 0.6MPa, starting stirring, heating, raising the temperature, controlling the reaction temperature to be 60 ℃, and carrying out hydrogenation reaction. Reacting for 8 hours, supplementing hydrogen for multiple times during the reaction, cooling to 25 ℃, releasing pressure, discharging, dissolving the obtained 3,3 '-diamino-4, 4' dihydroxybiphenyl solution in 50mL of 5 wt% hydrochloric acid solution containing 0.4g of anhydrous stannous chloride, filtering out the catalyst, adding 36 wt% concentrated hydrochloric acid to adjust the pH value to 2, standing for 12 hours, carrying out suction filtration, and carrying out vacuum drying on a filter cake to obtain a white solid product 3,3 '-diamino-4, 4' dihydroxybiphenyl hydrochloride 3.47g, wherein the HPLC analysis mass fraction is 85.67%, and the yield is 70.98%.
Example 4
Adding 4g of 3,3 '-dinitro-4, 4' dihydroxybiphenyl, 500mL of absolute ethyl alcohol and 0.4g of Pd/C (5%) as a catalyst into a 2000mL autoclave with a stirring and a built-in condensing tube, replacing gas in the autoclave with nitrogen for three times, then replacing gas in the autoclave with hydrogen for three times, wherein the pressure in each time is 0.4MPa, then maintaining the pressure of the hydrogen in the autoclave at 0.4MPa, starting stirring, heating, raising the temperature, controlling the reaction temperature at 50 ℃, and carrying out hydrogenation reaction. Reacting for 8 hours, supplementing hydrogen for multiple times during the reaction, cooling to 25 ℃, decompressing, discharging, dissolving the obtained 3,3 '-diamino-4, 4' dihydroxybiphenyl solution in 50mL of 5 wt% hydrochloric acid solution containing 0.4g of anhydrous stannous chloride, filtering out the catalyst, adding 36 wt% concentrated hydrochloric acid to adjust the pH value to 2, standing for 12 hours, carrying out suction filtration, and carrying out vacuum drying on a filter cake to obtain a white solid product 3,3 '-diamino-4, 4' dihydroxybiphenyl hydrochloride 3.01g, wherein the HPLC analysis mass fraction is 92.36%, and the yield is 66.37%.
Example 5
Adding 4g of 3,3 '-dinitro-4, 4' dihydroxybiphenyl, 500mL of absolute ethyl alcohol and 0.4g of Pd/C (5%) as a catalyst into a 2000mL autoclave with a stirring and a built-in condensing tube, replacing gas in the autoclave with nitrogen for three times, then replacing gas in the autoclave with hydrogen for three times, wherein the pressure in each time is 0.4MPa, then maintaining the pressure of the hydrogen in the autoclave at 0.8MPa, starting stirring, heating, raising the temperature, controlling the reaction temperature at 50 ℃ and carrying out hydrogenation reaction. Reacting for 8 hours, supplementing hydrogen for multiple times during the reaction, cooling to 25 ℃, releasing pressure, discharging, dissolving the obtained 3,3 '-diamino-4, 4' dihydroxybiphenyl solution in 50mL of 5 wt% hydrochloric acid solution containing 0.4g of anhydrous stannous chloride, filtering out the catalyst, adding 36 wt% concentrated hydrochloric acid to adjust the pH value to 2, standing for 12 hours, carrying out suction filtration, and carrying out vacuum drying on a filter cake to obtain a white solid product 3,3 '-diamino-4, 4' dihydroxybiphenyl hydrochloride 3.11g, wherein the HPLC analysis mass fraction is 90.68%, and the yield is 67.33%.
Example 6
Adding 4g of 3,3 '-dinitro-4, 4' dihydroxybiphenyl, 500mL of absolute ethyl alcohol and 0.4g of Pd/C (5%) as a catalyst into a 2000mL autoclave with a stirring and a built-in condensing tube, replacing gas in the autoclave with nitrogen for three times, then replacing gas in the autoclave with hydrogen for three times, wherein the pressure in each time is 0.6MPa, then maintaining the pressure of the hydrogen in the autoclave at 0.6MPa, starting stirring, heating, raising the temperature, controlling the reaction temperature at 50 ℃, and carrying out hydrogenation reaction. Reacting for 7 hours, supplementing hydrogen for multiple times during the reaction, cooling to 25 ℃, decompressing, discharging, dissolving the obtained 3,3 '-diamino-4, 4' dihydroxybiphenyl solution in 50mL of 5 wt% hydrochloric acid solution containing 0.4g of anhydrous stannous chloride, filtering out the catalyst, adding 36 wt% concentrated hydrochloric acid to adjust the pH value to 2, standing for 12 hours, carrying out suction filtration, and carrying out vacuum drying on a filter cake to obtain a white solid product 3,3 '-diamino-4, 4' dihydroxybiphenyl hydrochloride 3.21g, wherein the HPLC analysis mass fraction is 89.93%, and the yield is 68.92%.
Example 7
Adding 4g of 3,3 '-dinitro-4, 4' dihydroxybiphenyl, 500mL of absolute ethyl alcohol and 0.4g of Pd/C (5%) as a catalyst into a 2000mL autoclave with a stirring and a built-in condensing tube, replacing gas in the autoclave with nitrogen for three times, then replacing gas in the autoclave with hydrogen for three times, wherein the pressure in each time is 0.6MPa, then maintaining the pressure of the hydrogen in the autoclave at 0.6MPa, starting stirring, heating, raising the temperature, controlling the reaction temperature at 50 ℃, and carrying out hydrogenation reaction. Reacting for 9 hours, supplementing hydrogen for multiple times during the reaction, cooling to 25 ℃, decompressing, discharging, dissolving the obtained 3,3 '-diamino-4, 4' dihydroxybiphenyl solution in 50mL of 5 wt% hydrochloric acid solution containing 0.4g of anhydrous stannous chloride, filtering out the catalyst, adding 36 wt% concentrated hydrochloric acid to adjust the pH value to 2, standing for 12 hours, carrying out suction filtration, and carrying out vacuum drying on a filter cake to obtain a white solid product, namely 3,3 '-diamino-4, 4' dihydroxybiphenyl hydrochloride 2.81g, wherein the HPLC analysis mass fraction is 93.67%, and the yield is 62.84%.
Example 8
Adding 4g of 3,3 '-dinitro-4, 4' dihydroxybiphenyl, 500mL of absolute ethyl alcohol and 0.4g of Pd/C (5%) as a catalyst into a 2000mL autoclave with a stirring and a built-in condensing tube, replacing gas in the autoclave with nitrogen for three times, then replacing gas in the autoclave with hydrogen for three times, wherein the pressure in each time is 0.6MPa, then maintaining the pressure of the hydrogen in the autoclave at 0.6MPa, starting stirring, heating, raising the temperature, controlling the reaction temperature at 50 ℃, and carrying out hydrogenation reaction. Reacting for 10 hours, supplementing hydrogen for multiple times during the reaction, cooling to 25 ℃, releasing pressure, discharging, dissolving the obtained 3,3 '-diamino-4, 4' dihydroxybiphenyl solution in 50mL of 5 wt% hydrochloric acid solution containing 0.4g of anhydrous stannous chloride, filtering out the catalyst, adding 36 wt% concentrated hydrochloric acid to adjust the pH value to 2, standing for 12 hours, carrying out suction filtration, and carrying out vacuum drying on a filter cake to obtain a white solid product, namely 2.99g of 3,3 '-diamino-4, 4' dihydroxybiphenyl hydrochloride, wherein the HPLC analysis mass fraction is 90.33%, and the yield is 64.48%.
Example 9
Adding 4g of 3,3 '-dinitro-4, 4' dihydroxybiphenyl, 500mL of absolute ethyl alcohol and 0.6g of Pd/C (5%) as a catalyst into a 2000mL autoclave with a stirring and a built-in condensing tube, replacing gas in the autoclave with nitrogen for three times, then replacing gas in the autoclave with hydrogen for three times, wherein the pressure in each time is 0.6MPa, then maintaining the pressure of the hydrogen in the autoclave at 0.6MPa, starting stirring, heating, raising the temperature, controlling the reaction temperature at 50 ℃, and carrying out hydrogenation reaction. Reacting for 8 hours, supplementing hydrogen for multiple times during the reaction, cooling to 25 ℃, decompressing, discharging, dissolving the obtained 3,3 '-diamino-4, 4' dihydroxybiphenyl solution in 50mL of 5 wt% hydrochloric acid solution containing 0.4g of anhydrous stannous chloride, filtering out the catalyst, adding 36 wt% concentrated hydrochloric acid to adjust the pH value to 2, standing for 12 hours, carrying out suction filtration, and carrying out vacuum drying on a filter cake to obtain a white solid product 3,3 '-diamino-4, 4' dihydroxybiphenyl hydrochloride 3.06g, wherein the HPLC analysis mass fraction is 94.38%, and the yield is 68.95%.
Example 10
Adding 4g of 3,3 '-dinitro-4, 4' dihydroxybiphenyl, 500mL of absolute ethyl alcohol and 0.8g of Pd/C (5%) as a catalyst into a 2000mL autoclave with a stirring and a built-in condensing tube, replacing gas in the autoclave with nitrogen for three times, then replacing gas in the autoclave with hydrogen for three times, wherein the pressure in each time is 0.6MPa, then maintaining the pressure of the hydrogen in the autoclave at 0.6MPa, starting stirring, heating, raising the temperature, controlling the reaction temperature at 50 ℃, and carrying out hydrogenation reaction. Reacting for 8 hours, supplementing hydrogen for multiple times during the reaction, cooling to 25 ℃, releasing pressure, discharging, dissolving the obtained 3,3 '-diamino-4, 4' dihydroxybiphenyl solution in 50mL of 5 wt% hydrochloric acid solution containing 0.4g of anhydrous stannous chloride, filtering out the catalyst, adding 36 wt% concentrated hydrochloric acid to adjust the pH value to 2, standing for 12 hours, carrying out suction filtration, and carrying out vacuum drying on a filter cake to obtain a white solid product 3,3 '-diamino-4, 4' dihydroxybiphenyl hydrochloride 3.07g, wherein the HPLC analysis mass fraction is 93.75%, and the yield is 68.72%.
Example 11
Adding 4g of 3,3 '-dinitro-4, 4' dihydroxybiphenyl, 400mL of absolute ethyl alcohol and 0.4g of Pd/C (5%) as a catalyst into a 2000mL autoclave with a stirring and a built-in condensing tube, replacing gas in the autoclave with nitrogen for three times, then replacing gas in the autoclave with hydrogen for three times, wherein the pressure in each time is 0.6MPa, then maintaining the pressure of the hydrogen in the autoclave at 0.6MPa, starting stirring, heating, raising the temperature, controlling the reaction temperature at 50 ℃, and carrying out hydrogenation reaction. Reacting for 8 hours, supplementing hydrogen for multiple times during the reaction, cooling to 25 ℃, decompressing, discharging, dissolving the obtained 3,3 '-diamino-4, 4' dihydroxybiphenyl solution in 50mL of 5 wt% hydrochloric acid solution containing 0.4g of anhydrous stannous chloride, filtering out the catalyst, adding 36 wt% concentrated hydrochloric acid to adjust the pH value to 2, standing for 12 hours, carrying out suction filtration, and carrying out vacuum drying on a filter cake to obtain a white solid product 3,3 '-diamino-4, 4' dihydroxybiphenyl hydrochloride 3.16g, wherein the HPLC analysis mass fraction is 90.68%, and the yield is 68.41%.
Example 12
Adding 4g of 3,3 '-dinitro-4, 4' dihydroxybiphenyl, 600mL of absolute ethyl alcohol and 0.4g of Pd/C (5%) as a catalyst into a 2000mL autoclave with a stirring and a built-in condensing tube, replacing gas in the autoclave with nitrogen for three times, then replacing gas in the autoclave with hydrogen for three times, wherein the pressure in each time is 0.6MPa, then maintaining the pressure of the hydrogen in the autoclave at 0.6MPa, starting stirring, heating, raising the temperature, controlling the reaction temperature at 50 ℃, and carrying out hydrogenation reaction. Reacting for 8 hours, supplementing hydrogen for multiple times during the reaction, cooling to 25 ℃, decompressing, discharging, dissolving the obtained 3,3 '-diamino-4, 4' dihydroxybiphenyl solution in 50mL of 5 wt% hydrochloric acid solution containing 0.4g of anhydrous stannous chloride, filtering out the catalyst, adding 36 wt% concentrated hydrochloric acid to adjust the pH value to 2, standing for 12 hours, carrying out suction filtration, and carrying out vacuum drying on a filter cake to obtain a white solid product, namely 2.95g of 3,3 '-diamino-4, 4' dihydroxybiphenyl hydrochloride, wherein the HPLC analysis mass fraction is 92.31%, and the yield is 65.02%.
Example 13
Adding 4g of 3,3 '-dinitro-4, 4' dihydroxybiphenyl, 500mL of absolute ethyl alcohol and 0.4g of Pd/C (5%) as a catalyst into a 2000mL autoclave with a stirring and a built-in condensing tube, replacing gas in the autoclave with nitrogen for three times, then replacing gas in the autoclave with hydrogen for three times, wherein the pressure in each time is 0.6MPa, then maintaining the pressure of the hydrogen in the autoclave at 0.6MPa, starting stirring, heating, raising the temperature, controlling the reaction temperature at 50 ℃, and carrying out hydrogenation reaction. Reacting for 8 hours, supplementing hydrogen for multiple times during the reaction, cooling to 25 ℃, decompressing, discharging, dissolving the obtained 3,3 '-diamino-4, 4' dihydroxybiphenyl solution in 50mL of 5 wt% hydrochloric acid solution containing 0.5g of anhydrous stannous chloride, filtering out the catalyst, adding 36 wt% concentrated hydrochloric acid to adjust the pH value to 2, standing for 12 hours, carrying out suction filtration, and carrying out vacuum drying on a filter cake to obtain a white solid product 3,3 '-diamino-4, 4' dihydroxybiphenyl hydrochloride 3.04g, wherein the HPLC analysis mass fraction is 98.37%, and the yield is 71.40%. Examples 14 to 16
The preparation process of example 1 was used, and tests were carried out under conditions other than the parameters described in the present invention, and the results showed that the obtained product had a poor effect.
Example 14
Adding 4g of 3,3 '-dinitro-4, 4' dihydroxybiphenyl, 500mL of absolute ethyl alcohol and 0.4g of Pd/C (5%) as a catalyst into a 2000mL autoclave with a stirring and a built-in condensing tube, replacing gas in the autoclave with nitrogen for three times, then replacing gas in the autoclave with hydrogen for three times, wherein the pressure in each time is 0.6MPa, then maintaining the pressure of the hydrogen in the autoclave at 0.6MPa, starting stirring, heating, raising the temperature, controlling the reaction temperature to be 30 ℃, and carrying out hydrogenation reaction. Reacting for 8 hours, supplementing hydrogen for multiple times during the reaction, cooling to 25 ℃, relieving pressure and discharging, dissolving the obtained 3,3 '-diamino-4, 4' dihydroxybiphenyl solution in 50mL of 5 wt% hydrochloric acid solution containing 0.4g of anhydrous stannous chloride, filtering out the catalyst, adding 36 wt% hydrochloric acid to adjust the pH value to 2, standing for 12 hours, carrying out suction filtration, and carrying out vacuum drying on a filter cake to obtain a white solid product, namely 3,3 '-diamino-4, 4' dihydroxybiphenyl hydrochloride, wherein the HPLC analysis mass fraction is 58.36%, and the yield is 58.10%.
Example 15
Adding 4g of 3,3 '-dinitro-4, 4' dihydroxybiphenyl, 500mL of absolute ethyl alcohol and 0.4g of Pd/C (5%) as a catalyst into a 2000mL autoclave with a stirring and a built-in condensing tube, replacing gas in the autoclave with nitrogen for three times, then replacing gas in the autoclave with hydrogen for three times, wherein the pressure in each time is 0.2MPa, then maintaining the pressure of the hydrogen in the autoclave at 0.2MPa, starting stirring, heating, raising the temperature, controlling the reaction temperature at 50 ℃, and carrying out hydrogenation reaction. Reacting for 8 hours, supplementing hydrogen for many times during the reaction, cooling to 25 ℃, relieving pressure and discharging, dissolving the obtained 3,3 '-diamino-4, 4' dihydroxybiphenyl solution in 50mL of 5 wt% hydrochloric acid solution containing 0.4g of anhydrous stannous chloride, filtering out the catalyst, adding 36 wt% hydrochloric acid to adjust the pH value to 2, standing for 12 hours, carrying out suction filtration, and carrying out vacuum drying on a filter cake to obtain a white solid product 3,3 '-diamino-4, 4' dihydroxybiphenyl hydrochloride 3.69g, wherein the HPLC analysis mass fraction is 67.36%, and the yield is 59.34%.
Example 16
Adding 4g of 3,3 '-dinitro-4, 4' dihydroxybiphenyl, 500mL of absolute ethyl alcohol and 0.2g of Pd/C (5%) as a catalyst into a 2000mL autoclave with a stirring and a built-in condensing tube, replacing gas in the autoclave with nitrogen for three times, then replacing gas in the autoclave with hydrogen for three times, wherein the pressure in each time is 0.6MPa, then maintaining the pressure of the hydrogen in the autoclave at 0.6MPa, starting stirring, heating, raising the temperature, controlling the reaction temperature at 50 ℃, and carrying out hydrogenation reaction. Reacting for 8 hours, supplementing hydrogen for many times during the reaction, cooling to 25 ℃, relieving pressure and discharging, dissolving the obtained 3,3 '-diamino-4, 4' dihydroxybiphenyl solution in 50mL of 5 wt% hydrochloric acid solution containing 0.4g of anhydrous stannous chloride, filtering out the catalyst, adding 36 wt% hydrochloric acid to adjust the pH value to 2, standing for 12 hours, carrying out suction filtration, and carrying out vacuum drying on a filter cake to obtain a white solid product 3,3 '-diamino-4, 4' dihydroxybiphenyl hydrochloride 3.57g, wherein the HPLC analysis mass fraction is 67.39%, and the yield is 57.44%.
Claims (10)
1. A method for synthesizing 3,3 '-diamino-4, 4' dihydroxybiphenyl hydrochloride, characterized in that the method comprises the following steps:
(1) adding 3,3 '-dinitro-4, 4' dihydroxybiphenyl, absolute ethyl alcohol and a Pd/C catalyst into an autoclave, exhausting air in the autoclave, and stirring for 7-10 hours at 40-60 ℃ and under the condition that the hydrogen pressure is 0.4-0.8 MPa to obtain a reaction liquid A containing 3,3 '-diamino-4, 4' dihydroxybiphenyl; the mass ratio of the 3,3 '-dinitro-4, 4' -dihydroxybiphenyl to the Pd/C catalyst is 1: 0.05 to 0.2; the volume of the absolute ethyl alcohol is 100-150 mL/g based on the mass of the 3,3 '-dinitro-4, 4' -dihydroxybiphenyl;
(2) mixing the reaction liquid A with hydrochloric acid solution of stannous chloride, filtering to remove a Pd/C catalyst, adding concentrated hydrochloric acid to adjust the pH value to 1-3, standing and crystallizing to obtain mixed liquid B, and carrying out aftertreatment on the mixed liquid B to obtain 3,3 '-diamino-4, 4' dihydroxy biphenyl hydrochloride; the mass ratio of the stannous chloride to the 3,3 '-dinitro-4, 4' -dihydroxy biphenyl is 1: 8-10, wherein the volume of the hydrochloric acid solution is 10-15 mL/g based on the mass of 3,3 '-dinitro-4, 4' -dihydroxybiphenyl, and the concentration of hydrochloric acid in the hydrochloric acid solution is 4-6 wt%.
2. The method for synthesizing 3,3 '-diamino-4, 4' dihydroxybiphenyl hydrochloride according to claim 1, wherein the method for exhausting the air in the autoclave in step (1) comprises: the gas in the kettle is replaced by nitrogen for three times, and then replaced by hydrogen for three times, wherein the pressure in each time is 0.6 MPa.
3. The method of synthesizing 3,3 '-diamino-4, 4' dihydroxybiphenyl hydrochloride according to claim 1, wherein: the Pd loading in the Pd/C catalyst was 5 wt%.
4. The method for synthesizing 3,3 '-diamino-4, 4' -dihydroxybiphenyl hydrochloride according to claim 1, wherein the reaction conditions in step (1) are 40-50 ℃ and 0.4-0.6 MPa for 8-9 hours.
5. The method of synthesizing 3,3 '-diamino-4, 4' dihydroxybiphenyl hydrochloride according to claim 1, wherein: in the step (1), the mass ratio of the 3,3 '-dinitro-4, 4' dihydroxy biphenyl to the Pd/C catalyst is 1: 0.1 to 0.2.
6. The method of synthesizing 3,3 '-diamino-4, 4' dihydroxybiphenyl hydrochloride according to claim 1, wherein: the volume of the absolute ethyl alcohol in the step (1) is 125mL/g based on the mass of the 3,3 '-dinitro-4, 4' dihydroxy biphenyl.
7. The method of synthesizing 3,3 '-diamino-4, 4' dihydroxybiphenyl hydrochloride according to claim 1, wherein: the standing time in the step (2) was 12 hours.
8. The method of synthesizing 3,3 '-diamino-4, 4' dihydroxybiphenyl hydrochloride according to claim 1, wherein: the mass ratio of the stannous chloride to the 3,3 '-dinitro-4, 4' -dihydroxy biphenyl is 1: 10, the volume of the hydrochloric acid solution is 12.5mL/g based on the mass of the 3,3 '-dinitro-4, 4' dihydroxybiphenyl, and the hydrochloric acid concentration in the hydrochloric acid solution is 5 wt%.
9. The method of synthesizing 3,3 '-diamino-4, 4' dihydroxybiphenyl hydrochloride according to claim 1, wherein: and (3) adding concentrated hydrochloric acid in the step (2) to adjust the pH to 2.
10. The method of synthesizing 3,3 '-diamino-4, 4' dihydroxybiphenyl hydrochloride according to claim 1, wherein said post-treatment comprises: and carrying out suction filtration on the obtained mixed solution B, and carrying out vacuum drying on a filter cake to obtain the 3,3 '-diamino-4, 4' dihydroxybiphenyl hydrochloride.
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