CN1569813A - Process for preparing 4,6-diamino resorcin - Google Patents
Process for preparing 4,6-diamino resorcin Download PDFInfo
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- CN1569813A CN1569813A CN 200410018278 CN200410018278A CN1569813A CN 1569813 A CN1569813 A CN 1569813A CN 200410018278 CN200410018278 CN 200410018278 CN 200410018278 A CN200410018278 A CN 200410018278A CN 1569813 A CN1569813 A CN 1569813A
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- organic solvent
- benzene
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Abstract
The invention discloses a process for preparing 4, 6-diamino resorcinol comprising the steps of, subjecting 4,6-dinitro-2-chlorin-1,3-dihydroxy benzene to catalytic hydrogenation with hydrogen under normal or medium pressure at normal temperature or heating condition, in organic solvent and at the presence of rare metals and transient metallic oxide catalyst, then collecting 4,6-diamino resorcinol from the reactant through the conventional methods.
Description
Technical field
The present invention relates to a kind ofly 4, the preparation method of 6-diamino resorcin relates in particular to 4, and 6-dinitrobenzene-2-chloro-1,3-dihydroxy-benzene are that raw material is through catalytic hydrogenation preparation 4, the method for 6-diamino resorcin.
Background technology
4, the 6-diamino resorcin is that the important structure unit of multiple polymer (particularly polybenzoxazole) is (referring to people's such as Wolf " Macromolecules " 1981,14:915).
Its structural formula is as follows:
US5399768 and US5371281 and US925358 have narrated by 4,6-dinitrobenzene-2-chloro-1, the 3-dihydroxy-benzene is through catalytic hydrogenation preparation 4, the method of 6-diamino resorcin, a significant disadvantages of described method is 4,6-dinitrobenzene-2-chloro-1, the 3-dihydroxy-benzene carries out heterogeneous catalyzed hydration with batch hydrogenation on the Pd/C catalyzer, expensive rare metal catalyst economy ground recirculation is used.
Summary of the invention
The technical issues that need to address of the present invention are to disclose a kind of newly 4, and 6-diamino resorcin preparation method is to overcome rare metal catalyzer that prior art the exists shortcoming used of recirculation economically.
Method of the present invention comprises the steps:
With 4,6-dinitrobenzene-2-chloro-1, the 3-dihydroxy-benzene in organic solvent and rare metal and catalyst of transition metal oxide in the presence of, under normal pressure or middle pressure and normal temperature or heating, carry out catalytic hydrogenation with hydrogen, the method for employing routine then collects 4 from reaction product, the 6-diamino resorcin, by 4,6-dinitrobenzene-2-chloro-1,3-dihydroxy-benzene are benchmark, 4,6-diamino resorcin mole yield can reach more than 90%.
The catalyzer of being addressed is by the stable carrier of described organic solvent is constituted with the rare metal and the transition metal oxide that are carried on this carrier;
The rare metal of being addressed comprises one or more in palladium, platinum, gold, ruthenium or the rhodium, preferred palladium or platinum, and its amount is the 0.1-10wt% of total catalyst weight;
The transition metal oxide of being addressed is one or more in copper, cobalt, iron or the manganese, preferably copper or cobalt, and its amount is the 1-10% of total catalyst weight;
The carrier of being addressed is a carrier well known in the art, comprises gac, silicon-dioxide, aluminum oxide or molecular sieve.
Preferred hydrogenation catalyst is for containing palladium 4～6wt%, cupric oxide 2-7%, cobalt oxide 3-7%, and all the other are gac.
Said Preparation of catalysts can be divided into for two steps, and the first step is the salpeter solution that floods copper and cobalt on gac, drying, roasting; The second step load rare metal, its method can adopt dipping method well known in the art to be prepared.
Catalyst consumption must be enough to make raw material change into 4 in the presence of hydroborating reagent the 6-diamino resorcin.Generally speaking, in every mole of dinitrobenzene chlorination dihydroxy-benzene with 0.02～1 mole catalyzer.In entire reaction course, every mole of dinitrobenzene chlorination dihydroxy-benzene catalyst consumption is the best with 0.02 mole to about 0.5 mole, preferably 0.02～0.2 mole.
The organic solvent of being addressed is with 4, and the organic solvent that the 6-diamino resorcin dissolves each other is to guarantee that catalyst separating is convenient and to recycle.Preferred organic comprises alcohol, ester, aromatic hydrocarbons, alkane aromatic hydrocarbons, preferably comprises C
1～C
5Unit alcohol, tetrahydrofuran (THF), benzene,toluene,xylene, ethyl acetate; Most preferably propyl alcohol or isopropylcarbinol, especially isopropylcarbinol.
Organic solvent and 4,6-dinitrobenzene-2-chloro-1, the weight ratio of 3-dihydroxy-benzene is:
Organic solvent: 4,6-dinitrobenzene-2-chloro-1,3-dihydroxy-benzene=1～50: 1 (mol);
Preferred 4～30: 1.
In the reaction medium, 4,6-dinitrobenzene-2-chloro-1, the suitable concentration of 3-dihydroxy-benzene must satisfy can reclaim this requirement of product effectively.For example, suitable concentration range is about 0.3～2mol/L, and being about good, the most desirable concentration with 0.65mol/L～1mol/L is 0.75 mole/L.
Reaction pressure is 1-7.5Mpa, preferred 1.5-4.0Mpa, especially 1.2-2Mpa, and temperature is 20-100 ℃, is preferably 20-80 ℃, especially 30-70 ℃.
Adopt method of the present invention, not only can once connect and once carry out repeatedly hydrogenation and catalyst activity does not reduce, and obtain 4 of high productive rate and high quality in economic especially mode, the 6-diamino resorcin, by 4,6-dinitrobenzene-2-chloro-1,3-dihydroxy-benzene are benchmark, 4,6-diamino resorcin mole yield can reach more than 90%.Therefore proposed by the invention 4,6-diamino resorcin method is a kind of highly effective 4, and the preparation method of 6-diamino resorcin has bigger suitability for industrialized production prospect.
Embodiment
Embodiment 1
Cocoanut active charcoal is ground, sieve 350 purpose active carbon powders, a certain amount of activated carbon is joined in 10% nitric acid, 80 ℃ of stirred in water bath 2 hours, filter then, become neutral with distilled water wash; Handle with water vapour again, oven dry, standby.
Cupric nitrate is dissolved in the deionized water, is made into 2.1 * 10
-1The copper nitrate solution of mol/L joins the 10g gac of above-mentioned processing in the 37ml copper nitrate aqueous solution, dipping 2h, and aging 24h in air, 100-110 ℃ of dry 24h in air, 250 ℃ of roasting 5h in retort furnace, it is standby promptly to obtain 5% (wt) CuO/C.Platinic chloride is dissolved in the deionized water, is made into 1.7 * 10
-2The platinum acid chloride solution of mol/L.The gac that is loaded with the Cu element is joined in the 278ml chloroplatinic acid aqueous solution, and dipping 2h adds the reduction of 8ml formaldehyde again, drip saturated sodium hydrogen carbonate solution simultaneously, control pH value is about 9, reacts constant to the pH value, and it is 5% Pt-Cu/C catalyzer that filtering drying promptly obtains Pt content.
In the reactor of 1000ml, add 70g 4,6-dinitrobenzene-2-chloro-1,3-dihydroxy-benzene, 300ml isopropylcarbinol, the above-mentioned 5%Pt-5%Cu/C of 7g.With N
2Import in this sealed reactor displaced air three times, use H again
2Replace three times.25 ℃ of temperature of reaction, pressure are 20Mpa.After reaction finished, reaction material liquid was cooled to room temperature, filtered, and it is reusable that catalyzer is stayed reactor, and filtrate is for containing 4, and the 6-diamino resorcin according to liquid-phase chromatographic analysis, calculates 4, and 6-diamino resorcin mole yield is 92%.
Further, its preparation can be become hydrochloride,, use N by a riser tube that filter is housed
2Reaction solution is pressed into 500ml contains 6g SnCl
22H
2In the 3N dilute hydrochloric acid solution of O, the 5%Pt-5%Cu/C catalyzer is stayed reactor.Isopropylcarbinol is removed in underpressure distillation, adds the concentrated hydrochloric acid of 250ml technical grade in distillate, and diamino resorcin hydrochlorate is precipitated out from flaxen solution.Filtration obtains white filter cake, and promptly 4,6-diamino resorcin hydrochlorate white crystal, its dry weight is 49g.
Embodiment 2
The 3%CuO/C preparation is with embodiment 1.Palladous chloride is dissolved in the deionized water, is made into 1.7 * 10
-2The palladium chloride solution of mol/L.The gac that is loaded with the Cu element is joined in the 278ml palladium chloride aqueous solution, and dipping 2h adds the reduction of 8ml formaldehyde again, drip saturated sodium hydrogen carbonate solution simultaneously, control pH value is about 9, reacts constant to the pH value, and it is 5% Pd-Cu/C catalyzer that filtering drying promptly obtains Pd content.
In the reactor of 1000ml, add 70g 4,6-dinitrobenzene-2-chloro-1,3-dihydroxy-benzene, 350ml propyl alcohol, the above-mentioned 5%Pd-3%Cu/C of 7g.With N
2Import in this sealed reactor displaced air three times, use H again
2Replace three times.H
2Pressure reaches 3Mpa, and temperature reaches 80 ℃.After reaction finished, reaction material liquid was cooled to room temperature, filtered, and it is reusable that catalyzer is stayed reactor, and filtrate is for containing 4, and the 6-diamino resorcin according to liquid-phase chromatographic analysis, calculates 4, and 6-diamino resorcin mole yield is 98%.
Further, its preparation can be become hydrochloride,, use N by a riser tube that filter is housed
2Reaction solution is pressed into 500ml contains 25g SnCl
22H
2In the 3N dilute hydrochloric acid solution of O, the 5%Pd-3%Cu/ catalyzer is stayed reactor.Propyl alcohol is removed in underpressure distillation, adds 250ml technical grade concentrated hydrochloric acid in distillate, and diamino resorcin hydrochlorate is precipitated out from flaxen solution.Filtration obtains white filter cake, i.e. diamino resorcin hydrochlorate white crystal, and its dry weight is 53g.
Embodiment 3
The processing of gac is with described in the embodiment 1.Xiao Suangu is dissolved in the deionized water, is made into 2.1 * 10
-1The cobalt nitrate solution of mol/L joins the 10g gac of handling in the 39ml cobalt nitrate aqueous solution, dipping 2h, and aging 24h in air, 100-110 ℃ of dry 24h in air, 250 ℃ of roasting 5h in retort furnace, it is standby promptly to obtain 5% (wt) CoO/C.Press the carrying method of Pt among the embodiment 1, be prepared into the 5%Pt-5%Co/C catalyzer.
In the reactor of 1000ml, add 70g 4,6-dinitrobenzene-2-chloro-1,3-dihydroxy-benzene, 350ml benzene, 7g 5%Pt-5%Co/C.With N
2Import in this sealed reactor displaced air three times, use H again
2Replace three times.H
2Pressure reaches 0.9Mpa, and temperature reaches 30 ℃.After reaction finished, reaction material liquid was cooled to room temperature, filtered, and it is reusable that catalyzer is stayed reactor, and filtrate is for containing 4, and the 6-diamino resorcin according to liquid-phase chromatographic analysis, calculates 4, and 6-diamino resorcin mole yield is 89.3%.
Further, its preparation can be become hydrochloride,, use N by a riser tube that filter is housed
2Reaction solution is pressed into 500ml contains 20gSnCl
22H
2In the 3N dilute hydrochloric acid solution of O, the 5%Pt-5%Co/C catalyzer is stayed reactor.Benzene is removed in underpressure distillation, adds 250ml technical grade concentrated hydrochloric acid in distillate, and diamino resorcin hydrochlorate is precipitated out from flaxen solution.Filtration obtains white filter cake, i.e. diamino resorcin hydrochlorate white crystal, and its dry weight is 48g.
Embodiment 4
Method by embodiment 1 makes the 5%Ru-5%Cu/C catalyzer.In the reactor of 1000ml, add 70g 4,6-dinitrobenzene-2-chloro-1,3-dihydroxy-benzene, 400ml toluene, 7g 5%Ru-5%Cu/C.With N
2Import in this sealed reactor displaced air three times, use H again
2Replace three times.H
2Pressure reaches 2Mpa, and temperature is a room temperature.After reaction finished, reaction material liquid was cooled to room temperature, filtered, and it is reusable that catalyzer is stayed reactor, and filtrate is for containing 4, and the 6-diamino resorcin according to liquid-phase chromatographic analysis, calculates 4, and 6-diamino resorcin mole yield is 80.1%.
Further, its preparation can be become hydrochloride,, use N by a riser tube that filter is housed
2Reaction solution is pressed into 500ml contains 20 SnCl
22H
2In the 3N dilute hydrochloric acid solution of O, the 5%Ru-5%Cu/C catalyzer is stayed reactor.Toluene is removed in underpressure distillation, adds 250ml technical grade concentrated hydrochloric acid in distillate, and diamino resorcin hydrochlorate is precipitated out from flaxen solution.Filtration obtains white filter cake, i.e. diamino resorcin hydrochlorate white crystal, and its dry weight is 43g.
Embodiment 5
In the reactor of 1000ml, add 70g 4,6-dinitrobenzene-2-chloro-1, the 5%Pd-5%Cu/C catalyzer that 3-dihydroxy-benzene, 410ml isopropylcarbinol, 7g embodiment 2 make.2Mpa, temperature is 20 ℃, and after reaction finished, reaction material liquid was cooled to room temperature, filtered, and it is reusable that catalyzer is stayed reactor, and the filtrate condensing crystal promptly obtains 4, the 6-diamino resorcin, 4,6-diamino resorcin mole yield is 91.5%.
Further, its preparation can be become hydrochloride,, use N by a riser tube that filter is housed
2Reaction solution is pressed into 500ml contains 20gSnCl
22H
2In the 3N dilute hydrochloric acid solution of O, the 5%Pd-5%Cu/C catalyzer is stayed reactor.Isopropylcarbinol is removed in underpressure distillation, adds the 250ml technical-grade hydrochloric acid in distillate, and diamino resorcin hydrochlorate is precipitated out from flaxen solution.Filtration obtains white filter cake, i.e. diamino resorcin hydrochlorate white crystal, and its dry weight is 49.9g.
Embodiment 6
In the reactor of 1000ml, add 70g 4,6-dinitrobenzene-2-chloro-1, the 5%Pd-5%Cu/C catalyzer that 3-dihydroxy-benzene, 250ml ethyl acetate, 7g embodiment 2 make.With N
2Import in this sealed reactor displaced air three times, use H again
2Replace three times.H
2Pressure reaches 1.5Mpa, 30 ℃ of temperature.After reaction finished, reaction material liquid was cooled to room temperature, filtered, and it is reusable that catalyzer is stayed reactor, and the filtrate condensing crystal promptly obtains 4, the 6-diamino resorcin, and 4,6-diamino resorcin mole yield is 91%.
Further, its preparation can be become hydrochloride,, use N by a riser tube that filter is housed
2Reaction solution is pressed into 500ml contains 20g SnCl
22H
2In the 3N dilute hydrochloric acid solution of O, the 5%Pd-5%Cu/C catalyzer is stayed reactor.Ethyl acetate is removed in underpressure distillation, adds 250ml technical grade concentrated hydrochloric acid in distillate, and diamino resorcin hydrochlorate is precipitated out from flaxen solution.Filtration obtains white filter cake, i.e. diamino resorcin hydrochlorate white crystal, and its dry weight is 50g.
Embodiment 7
Mode similarly to Example 5 adopts and has used 20 times catalyzer, adds 70g 4,6-dinitrobenzene-2-chloro-1,3-dihydroxy-benzene, 410ml isopropylcarbinol.With N
2Import in this sealed reactor displaced air three times, use H again
2Replace three times.H
2Pressure reaches 1.5Mpa, 20 ℃ of temperature.After reaction finished, reaction material liquid was cooled to room temperature, filtered, and it is reusable that catalyzer is stayed reactor, and filtrate is for containing 4, and the 6-diamino resorcin according to liquid-phase chromatographic analysis, calculates 4, and 6-diamino resorcin mole yield is 90.5%.
Further, its preparation can be become hydrochloride,, use N by a riser tube that filter is housed
2Reaction solution is pressed into 500ml contains 20 SnCl
22H
2In the 3N dilute hydrochloric acid solution of O, the 5%Pd-5%Cu/C catalyzer is stayed reactor.Isopropylcarbinol is removed in underpressure distillation, adds 250ml technical grade concentrated hydrochloric acid in distillate, and diamino resorcin hydrochlorate is precipitated out from flaxen solution.Filtration obtains white filter cake, i.e. diamino resorcin hydrochlorate white crystal, and its dry weight is 49.4g.
Claims (10)
1. one kind 4, the preparation method of 6-diamino resorcin is characterized in that, comprises the steps:
With 4,6-dinitrobenzene-2-chloro-1, the 3-dihydroxy-benzene in organic solvent and rare metal and catalyst of transition metal oxide in the presence of, under normal pressure or middle pressure and normal temperature or heating, carry out catalytic hydrogenation with hydrogen, adopt conventional method from reaction product, to collect 4, the 6-diamino resorcin then;
The catalyzer of being addressed is by the stable carrier of described organic solvent is constituted with the rare metal and the transition metal oxide that are carried on this carrier;
The rare metal of being addressed comprises one or more in palladium, platinum, gold, ruthenium or the rhodium, preferred palladium or platinum;
The transition metal oxide of being addressed is one or more in copper, cobalt, iron or the manganese, preferably copper or cobalt, and its amount is the 1-10% of total catalyst weight;
2. method according to claim 1 is characterized in that the rare metal amount of being addressed is the 0.1-10wt% of total catalyst weight.
3. method according to claim 1 is characterized in that the transition metal oxide amount of being addressed is the 1-10% of total catalyst weight.
4. method according to claim 1 is characterized in that the carrier of being addressed comprises gac, silicon-dioxide, aluminum oxide or molecular sieve.
5. method according to claim 1 is characterized in that, the component of hydrogenation catalyst and weight percent content are: palladium 4～6wt%, cupric oxide 2-7%, cobalt oxide 3-7%, gac surplus.
6. method according to claim 1 is characterized in that, in every mole of dinitrobenzene chlorination dihydroxy-benzene with 0.02～1 mole catalyzer.
7. method according to claim 1 is characterized in that, the organic solvent of being addressed is with 4, the organic solvent that the 6-diamino resorcin dissolves each other.
8. method according to claim 7 is characterized in that organic solvent is selected from C
1～C
5Unit alcohol, tetrahydrofuran (THF), benzene,toluene,xylene or ethyl acetate in a kind of.
9. method according to claim 1 is characterized in that, organic solvent and 4, and 6-dinitrobenzene-2-chloro-1, the weight ratio of 3-dihydroxy-benzene is:
Organic solvent: 4,6-dinitrobenzene-2-chloro-1,3-dihydroxy-benzene=1～50: 1 (mol);
10. according to each described method of claim 1～9, it is characterized in that reaction pressure is 1-7.5Mpa, temperature is 20-100 ℃.
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| CN 200410018278 CN1569813A (en) | 2004-05-12 | 2004-05-12 | Process for preparing 4,6-diamino resorcin |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101962326A (en) * | 2010-08-20 | 2011-02-02 | 南化集团研究院 | Method for preparing 4,6-diamino resorcinol hydrochloride by continuous hydrogenation |
| US9045381B2 (en) | 2010-10-19 | 2015-06-02 | Yeda Research And Development Co. Ltd. | Ruthenium complexes and their uses in processes for formation and/or hydrogenation of esters, amides and derivatives thereof |
| US10533028B2 (en) | 2014-09-04 | 2020-01-14 | Yeda Research And Development Co. Ltd. | Ruthenium complexes and their uses as catalysts in processes for formation and/or hydrogenation of esters, amides and related reactions |
| US10562767B2 (en) | 2014-09-04 | 2020-02-18 | Yeda Research And Development Co. Ltd. | Liquid-organic hydrogen carrier systems based on catalytic peptide formation and hydrogenation |
-
2004
- 2004-05-12 CN CN 200410018278 patent/CN1569813A/en active Pending
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101962326A (en) * | 2010-08-20 | 2011-02-02 | 南化集团研究院 | Method for preparing 4,6-diamino resorcinol hydrochloride by continuous hydrogenation |
| US9045381B2 (en) | 2010-10-19 | 2015-06-02 | Yeda Research And Development Co. Ltd. | Ruthenium complexes and their uses in processes for formation and/or hydrogenation of esters, amides and derivatives thereof |
| US10533028B2 (en) | 2014-09-04 | 2020-01-14 | Yeda Research And Development Co. Ltd. | Ruthenium complexes and their uses as catalysts in processes for formation and/or hydrogenation of esters, amides and related reactions |
| US10562767B2 (en) | 2014-09-04 | 2020-02-18 | Yeda Research And Development Co. Ltd. | Liquid-organic hydrogen carrier systems based on catalytic peptide formation and hydrogenation |
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