CA1241664A - Process for the preparation of 1-naphthylamine - Google Patents
Process for the preparation of 1-naphthylamineInfo
- Publication number
- CA1241664A CA1241664A CA000490275A CA490275A CA1241664A CA 1241664 A CA1241664 A CA 1241664A CA 000490275 A CA000490275 A CA 000490275A CA 490275 A CA490275 A CA 490275A CA 1241664 A CA1241664 A CA 1241664A
- Authority
- CA
- Canada
- Prior art keywords
- process according
- nitronaphthalene
- weight
- ppm
- activated charcoal
- 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.)
- Expired
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C209/00—Preparation of compounds containing amino groups bound to a carbon skeleton
- C07C209/30—Preparation of compounds containing amino groups bound to a carbon skeleton by reduction of nitrogen-to-oxygen or nitrogen-to-nitrogen bonds
- C07C209/32—Preparation of compounds containing amino groups bound to a carbon skeleton by reduction of nitrogen-to-oxygen or nitrogen-to-nitrogen bonds by reduction of nitro groups
- C07C209/36—Preparation of compounds containing amino groups bound to a carbon skeleton by reduction of nitrogen-to-oxygen or nitrogen-to-nitrogen bonds by reduction of nitro groups by reduction of nitro groups bound to carbon atoms of six-membered aromatic rings in presence of hydrogen-containing gases and a catalyst
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C211/00—Compounds containing amino groups bound to a carbon skeleton
- C07C211/43—Compounds containing amino groups bound to a carbon skeleton having amino groups bound to carbon atoms of six-membered aromatic rings of the carbon skeleton
- C07C211/57—Compounds containing amino groups bound to a carbon skeleton having amino groups bound to carbon atoms of six-membered aromatic rings of the carbon skeleton having amino groups bound to carbon atoms of six-membered aromatic rings being part of condensed ring systems of the carbon skeleton
- C07C211/58—Naphthylamines; N-substituted derivatives thereof
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
- Low-Molecular Organic Synthesis Reactions Using Catalysts (AREA)
Abstract
Process for the preparation of 1-naphthylamine Abstract 1-Naphthylamine is prepared by the hydrogenation of 1-nitronophthalene which is virtually free of sulphur compounds and isomeric nitronaphthalenes, at elevated temperature and elevated pressure, in the presence of inert organic solvents miscible with water and in the presence of a platinum/activated charcoal catalyst, the average residence time of the reaction mixture in the reactor being 3 to 30 minutes.
Description
The invention relates to a process for the preparation of 1-naphthylamine by the catalytic hydro-genation of 1-nitronaphthalene at elevated temperature and elevated pressure, in the presence of inert organic solvents miscible with water.
Conventionally, 1-naphthylamine is prepared on the industrial scale by the reduction of 1-nitronaphthalene with iron in dilute hydrochloric acid (Béchamp reduction) or catalytically with hydrogen in the presence of nickel catalysts (for example Raney nickel3 or by the reaction of 1-naphthol with ammonia and ammonium bisulphite (Bucherer reaction) (cf., for example, Kirk-~thmer, volume 4, 1st edition, pages 258-260). Thus, for example, the yield of the reduction with iron is about 90X of theory (cf. Kirk-Othmer, volume I, 1st Edition, page 260); for catalytic hydrogenation with nickel catalysts, yields of over 90%, for example 96.4~, are indicated (cf., U.S.
Patent 2,105,321, J. Chem. Soc. Japan, 54, 371 to 373 (1951), and C.A~ 48, 1979d).
The catalytic reduction processes have the dis-advantage that they cannot successfully be applied also to the reduction of purified 1-nitronaphthalene which is virtually free of sulphur compounds and the 2-nitro-naphthalene isomer. As shown by our own experiments with purified 1-nitronaphthalene, the desired naphthyL-amine is only wormed as a by-product in the catalytic hydrogenation with Raney nickel under the usual reaction conditions. Attack by the hydrogen takes place simul-taneously and predominantly on the aromatic nucleus and the main products obtained are the undesired amino com-pounds hydrogenated on the nucleus (cf. Example 2 in the examples section).
The hydrogenation of nitronaphthalenes at elevated temperature and elevated pressure, in the Le A 23 116 presence of, for example, nobLe metaL catalysts which may be supported, has also been described (cf., for example, German Offenlegungsschriften 2,456,308 and Z,519, 838). However, the hydrogenations of nitro compounds described in the said German ~ffenlegungsschrif~er, require special conditions which entail some disadvantages for a large-sca~e process. Thus, the hydrogenation according to German Offenlegungsschrift 2,456,308 is carried out with the addition of special diluents in which the nitro 10 compound to be hydrogenated is soluble and the hydrogena-tion product, consisting essentially of amino compound and water, is virtually insoluble. The process described in German Offenlegungsschrift 2,519,838 takes place in the trickle phase on fixed catalysts. disadvantages of the 15 process of German Offenlegungsschrift 2,456,308 are the addition of special diluents,~ the high dilution of the reactants with the resulting low throughputs, and the industrially expensive recovery of the solvents, which detract from the economy of the process.
In the process of German Offenlegungsschrift 2, 519,838, the trickle phase is of little advantage because this reaction is also carried out at high dilution, permitting only low throughputs, which again detracts from the economy of the process. Moreover, deposits on 25 the fixed-bed catalyst are to be expected, which can lead to high pressure losses in the unit and even to blockages in some cases.
A process has now been found for the preparation of 1-naphthylamine by the catalytic hydrogenation of 1-30 nitronaphthalene at elevated temperature and elevated pressure, in the presence of inert organic solvents miscible with water, which is characterized in that purified 1-nitronaphthalene~ which is virtually free of sulphur compounds and the 2-nitronaphthalene isomer, is 35 hydrogenated at temperatures of 150 to 250C and pressures of 50 to 300 bar, in the presence of platinum/activated Le A 23 116 Lo charcoaL, the average residence time of the reaction mixture in the reactor being 3 to 30 minutes.
According to the invention, purified 1-nitro-naphthalene which is virtually free of sulphur compounds, such as nitrobenzothiophenes, and free of the 2-nitro-naphthalene isomer is used in the process.
The purified 1-nitronaphthalene usually contains less than 10 ppm of sulphur, preferably 3 to 5 ppm of sulphur, in the form of sulphur compounds, and less than 10 ppm, preferably 1 to 3 ppm, of 2-nitronaphthalene~
The hydrogenation of the purified 1-nitro-naphthalene is preferably carried out at temperatures of 160 to 200C and at pressures (H2) of 80 to 150 bar.
The hydrogenation catalyst used in the process according to the invention is a platinum/activated char-coal catalyst in which the platinum is applied to the activated charcoal support in quantities of 0.3 to 7X by weight, preferably 0.5 Jo 2% by weight, based on the finished catalyst. The hydrogenation catalyst is pre-~0 pared in a known manner by soaking or spraying the acti-vated charcoal support with an aqueous platinum salt solution, for example a hexachloroplatinic acid SGlution ~H2PtCl6). The platinum compound applied to the support is then reduced to the metal in a customary manner, for example with formaldehyde and hydrazine in alkaline sGlution or with hydrogen In the circuit of the continuous process, there are 1 to 2% by weight of the Pttactivated charcoal catalyst, based on the liquid contents of the hydrogenating unit.
The quantity of fresh catalyst used is generally about 2 to 20 9, preferably 4 to 8 9, based on 1 kmol of the 1-nitronaphthalene used.
According to the invention, the reduction of the purified 1-nitronaphthalene is carried out in the presence of inert organic solvents miscible with water, such as lower aliphatic and/or cycloaliphatic alcohols Examples Le A 23 116 of lower alcohols which may be mentioned are methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol and/or tert.-butanol, preferably isopropanol.
The quantity ox organic solvent used is not criticaL and Jan easily be determined by means of pre-~iminary experiments Usually, about 1 to 5 parts by weight, preferabLy 1.5 to 3 parts by weight, ox soLvent are used, based on 1 part by weight of 1~nitronaphthalene.
The process according to the invention is carried out in such a way that the average residence time of the reaction mixture in the reactor is 3 to 30, preferabLy 5 to 20 and particularly preferabLy 8 to 12 minutes The process according to the invention can be carried out either batch~ise or continuously. It is preferably carried out continuously.
The 1-nitronaphthalene is obtained in high purity (I 99.5%) and in high yields (> 99~) by the process according to the invention.
The process according to the invention also turns out to be so advantageous industrially because no special solvent systems are used (cf. German Offenlegungsschrift
Conventionally, 1-naphthylamine is prepared on the industrial scale by the reduction of 1-nitronaphthalene with iron in dilute hydrochloric acid (Béchamp reduction) or catalytically with hydrogen in the presence of nickel catalysts (for example Raney nickel3 or by the reaction of 1-naphthol with ammonia and ammonium bisulphite (Bucherer reaction) (cf., for example, Kirk-~thmer, volume 4, 1st edition, pages 258-260). Thus, for example, the yield of the reduction with iron is about 90X of theory (cf. Kirk-Othmer, volume I, 1st Edition, page 260); for catalytic hydrogenation with nickel catalysts, yields of over 90%, for example 96.4~, are indicated (cf., U.S.
Patent 2,105,321, J. Chem. Soc. Japan, 54, 371 to 373 (1951), and C.A~ 48, 1979d).
The catalytic reduction processes have the dis-advantage that they cannot successfully be applied also to the reduction of purified 1-nitronaphthalene which is virtually free of sulphur compounds and the 2-nitro-naphthalene isomer. As shown by our own experiments with purified 1-nitronaphthalene, the desired naphthyL-amine is only wormed as a by-product in the catalytic hydrogenation with Raney nickel under the usual reaction conditions. Attack by the hydrogen takes place simul-taneously and predominantly on the aromatic nucleus and the main products obtained are the undesired amino com-pounds hydrogenated on the nucleus (cf. Example 2 in the examples section).
The hydrogenation of nitronaphthalenes at elevated temperature and elevated pressure, in the Le A 23 116 presence of, for example, nobLe metaL catalysts which may be supported, has also been described (cf., for example, German Offenlegungsschriften 2,456,308 and Z,519, 838). However, the hydrogenations of nitro compounds described in the said German ~ffenlegungsschrif~er, require special conditions which entail some disadvantages for a large-sca~e process. Thus, the hydrogenation according to German Offenlegungsschrift 2,456,308 is carried out with the addition of special diluents in which the nitro 10 compound to be hydrogenated is soluble and the hydrogena-tion product, consisting essentially of amino compound and water, is virtually insoluble. The process described in German Offenlegungsschrift 2,519,838 takes place in the trickle phase on fixed catalysts. disadvantages of the 15 process of German Offenlegungsschrift 2,456,308 are the addition of special diluents,~ the high dilution of the reactants with the resulting low throughputs, and the industrially expensive recovery of the solvents, which detract from the economy of the process.
In the process of German Offenlegungsschrift 2, 519,838, the trickle phase is of little advantage because this reaction is also carried out at high dilution, permitting only low throughputs, which again detracts from the economy of the process. Moreover, deposits on 25 the fixed-bed catalyst are to be expected, which can lead to high pressure losses in the unit and even to blockages in some cases.
A process has now been found for the preparation of 1-naphthylamine by the catalytic hydrogenation of 1-30 nitronaphthalene at elevated temperature and elevated pressure, in the presence of inert organic solvents miscible with water, which is characterized in that purified 1-nitronaphthalene~ which is virtually free of sulphur compounds and the 2-nitronaphthalene isomer, is 35 hydrogenated at temperatures of 150 to 250C and pressures of 50 to 300 bar, in the presence of platinum/activated Le A 23 116 Lo charcoaL, the average residence time of the reaction mixture in the reactor being 3 to 30 minutes.
According to the invention, purified 1-nitro-naphthalene which is virtually free of sulphur compounds, such as nitrobenzothiophenes, and free of the 2-nitro-naphthalene isomer is used in the process.
The purified 1-nitronaphthalene usually contains less than 10 ppm of sulphur, preferably 3 to 5 ppm of sulphur, in the form of sulphur compounds, and less than 10 ppm, preferably 1 to 3 ppm, of 2-nitronaphthalene~
The hydrogenation of the purified 1-nitro-naphthalene is preferably carried out at temperatures of 160 to 200C and at pressures (H2) of 80 to 150 bar.
The hydrogenation catalyst used in the process according to the invention is a platinum/activated char-coal catalyst in which the platinum is applied to the activated charcoal support in quantities of 0.3 to 7X by weight, preferably 0.5 Jo 2% by weight, based on the finished catalyst. The hydrogenation catalyst is pre-~0 pared in a known manner by soaking or spraying the acti-vated charcoal support with an aqueous platinum salt solution, for example a hexachloroplatinic acid SGlution ~H2PtCl6). The platinum compound applied to the support is then reduced to the metal in a customary manner, for example with formaldehyde and hydrazine in alkaline sGlution or with hydrogen In the circuit of the continuous process, there are 1 to 2% by weight of the Pttactivated charcoal catalyst, based on the liquid contents of the hydrogenating unit.
The quantity of fresh catalyst used is generally about 2 to 20 9, preferably 4 to 8 9, based on 1 kmol of the 1-nitronaphthalene used.
According to the invention, the reduction of the purified 1-nitronaphthalene is carried out in the presence of inert organic solvents miscible with water, such as lower aliphatic and/or cycloaliphatic alcohols Examples Le A 23 116 of lower alcohols which may be mentioned are methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol and/or tert.-butanol, preferably isopropanol.
The quantity ox organic solvent used is not criticaL and Jan easily be determined by means of pre-~iminary experiments Usually, about 1 to 5 parts by weight, preferabLy 1.5 to 3 parts by weight, ox soLvent are used, based on 1 part by weight of 1~nitronaphthalene.
The process according to the invention is carried out in such a way that the average residence time of the reaction mixture in the reactor is 3 to 30, preferabLy 5 to 20 and particularly preferabLy 8 to 12 minutes The process according to the invention can be carried out either batch~ise or continuously. It is preferably carried out continuously.
The 1-nitronaphthalene is obtained in high purity (I 99.5%) and in high yields (> 99~) by the process according to the invention.
The process according to the invention also turns out to be so advantageous industrially because no special solvent systems are used (cf. German Offenlegungsschrift
2,456,308 in this respect), which, inter alia, have to be worked up in an industrially expensive manner, and no special catalysts, for example catalysts provided with specific additives (metal doping agents), or partially poisoned catalysts are used, which detract from the economy of the process on account of the high manufacturing costs.
Furthermore, it is particularly surprising that not all noble metal catalysts are equally suitable for the process according to the invention, but only the platinum-on-activated charcoal catalyst described above (cf., in this context, Comparative Example 3 in the examples section).
Example_1 2000 kg of purified 1-nitronaphthalene containing Le A 23 116
Furthermore, it is particularly surprising that not all noble metal catalysts are equally suitable for the process according to the invention, but only the platinum-on-activated charcoal catalyst described above (cf., in this context, Comparative Example 3 in the examples section).
Example_1 2000 kg of purified 1-nitronaphthalene containing Le A 23 116
3 ppm of sulphur in the form of sulphur compounds and containing 3 ppm of 2-nitronaphthalene, 4200 kg of iso-propanol/water mixture containing about 15% by weight ot water and 3000 kg of finished product solution con-taining the catalyst are pumped continuously, per hour,into the reactors of a system consisting of two main reactors and one follow-up reactor each having a capacity of 450 litres. In the circuit there are 1 to 2X by weight of catalyst l platinum-on-activated charcoal).
Approx. 0.05 to 0~1 kg of spent catalyst is replaced per hour. The hydrogen pressure is kept at 100 bar and the temperature is kept at 160 to 195C by means of cooling water. After a residence time of about minutes, the product, which is completely converted and virtually free of nitro compounds, it withdrawn from the reactor.
The pH of the solution containing the diamine compound is about 9 to 12. The isopropanol/water mixture recovered by distillation can be used again directly in the reaction without further purification. The crude, almost colourless 1-naphthylamine substantially freed of water has a solidification point of 48.4C; the yield is 99.5% of theory; the purity of the product is 99.7X.
Example 2 In the abovementioned apparatus, 2000 kg of purified 1-nitronaphthalene were hydrogenated per hour, under the same conditions as described in Example 1, in the presence of Raney nickel (doped with 15X of iron) (catalyst concentration in the circuit: approx. 3%).
1-Naphthylamine was formed n only 48.1% yield and various amino compounds partially and completely hydrogenated on the nucleus (aminodecalin and aminotetralins) were formed in 51.9X yield.
Example 3 1-Nitronaphthalene was hydrogenated in the presence of 1Z palladium-on-activated charcoal under con-ditions comparable to those described in Example 1. A
Le A 23 116 mixture consisting of only 90X of 1 naphthylamine and 10X
of amino compounds hydrogenated on the nucleus was formed in quantitative yield Le A 23 116
Approx. 0.05 to 0~1 kg of spent catalyst is replaced per hour. The hydrogen pressure is kept at 100 bar and the temperature is kept at 160 to 195C by means of cooling water. After a residence time of about minutes, the product, which is completely converted and virtually free of nitro compounds, it withdrawn from the reactor.
The pH of the solution containing the diamine compound is about 9 to 12. The isopropanol/water mixture recovered by distillation can be used again directly in the reaction without further purification. The crude, almost colourless 1-naphthylamine substantially freed of water has a solidification point of 48.4C; the yield is 99.5% of theory; the purity of the product is 99.7X.
Example 2 In the abovementioned apparatus, 2000 kg of purified 1-nitronaphthalene were hydrogenated per hour, under the same conditions as described in Example 1, in the presence of Raney nickel (doped with 15X of iron) (catalyst concentration in the circuit: approx. 3%).
1-Naphthylamine was formed n only 48.1% yield and various amino compounds partially and completely hydrogenated on the nucleus (aminodecalin and aminotetralins) were formed in 51.9X yield.
Example 3 1-Nitronaphthalene was hydrogenated in the presence of 1Z palladium-on-activated charcoal under con-ditions comparable to those described in Example 1. A
Le A 23 116 mixture consisting of only 90X of 1 naphthylamine and 10X
of amino compounds hydrogenated on the nucleus was formed in quantitative yield Le A 23 116
Claims (16)
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. A process for preparing 1-naphthylamine by catalytic hy-drogenation of 1-nitronaphthalene at elevated temperature and ele-vated pressure, in contact with an inert organic solvent miscible with water, which process comprises hydrogenating, in a reactor, pu-rified 1-nitronaphthalene substantially free of sulphur compounds and 2-nitronaphthalene isomer, at a temperature of 150 to 250°C and a pressure of 50 to 300 bar, in contact with platinum/activated charcoal, wherein the average residence time of the reaction mixture in the reactor being 3 to 30 minutes.
2. A process according to claim 1, wherein the 1-nitronaph-thalene contains less than 10 ppm of sulphur in the form of sulphur compounds.
3. A process according to claim 1 wherein the solvent is a lower aliphatic alcohol or cycloaliphatic alcohol.
4. A process according to claim 1, 2 or 3, wherein the 1-nitronaphthalene contains 3 to 5 ppm of sulphur in the form of sul-phur compounds.
5. A process according to claim 1, 2 or 3, wherein the 1-nitronaphthalene contains less than 10 ppm of 2-nitronaphthalene.
6. A process according to claim 1, 2 or 3, wherein the 1-nitronaphthalene contains 1 to 3 ppm of 2-nitronaphthalene.
7. A process according to claim 1, 2 or 3, wherein the reac-tion is effected at a temperature of 160 to 200°C.
8. A process according to claim 1, 2 or 3, wherein the reac-tion is effected at a pressure of 80 to 150 bar.
9. A process according to claim 1, 2 or 3, wherein the aver-age residence time of the reaction mixture in the reactor is 5 to 20 minutes.
10. A process according to claim 1, 2 or 3, wherein the 1-nitronaphthalene contains 1 to 3 ppm of 2-nitronaphthalene, the reaction is effected at a temperature of 160 to 200°C and a pressure of 80 to 150 bar and the average residence time of the reaction mix-ture in the reactor is 5 to 20 minutes.
11. A process according to claim 1, 2 or 3, wherein the pla-tinum is applied to the activated charcoal in quantities of 0.3 to 7% by weight, based on the -total weight of the platinum/activated charcoal.
12. A process according to claim 1, 2 or 3, wherein the pla-tinum is applied to the activated charcoal in quantities of 0.5 to 2% by weight, based on the total weight of the platinum/activated charcoal.
13. A process according to claim 1, 2 or 3, wherein the sol-vent is selected from the group consisting of methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol and tert.butanol.
14. A process according to claim 1, 2 or 3, wherein 1 to 5 parts by weight of solvent are used per 1 part by weight of the 1-nitronaphthalene.
15. A process according to claim 1, 2 or 3, wherein 1.5 to 3 parts by weight of solvent are used per 1 part by weight of the 1-nitronaphthalene.
16. A process according to claim 1, 2 or 3, wherein the resi-dence time is 8 to 12 minutes.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DEP3433240.5 | 1984-09-11 | ||
| DE19843433240 DE3433240A1 (en) | 1984-09-11 | 1984-09-11 | METHOD FOR PRODUCING 1-NAPHTHYLAMINE |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1241664A true CA1241664A (en) | 1988-09-06 |
Family
ID=6245069
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000490275A Expired CA1241664A (en) | 1984-09-11 | 1985-09-09 | Process for the preparation of 1-naphthylamine |
Country Status (5)
| Country | Link |
|---|---|
| EP (1) | EP0174563B1 (en) |
| JP (1) | JPS6168451A (en) |
| KR (1) | KR920005379B1 (en) |
| CA (1) | CA1241664A (en) |
| DE (2) | DE3433240A1 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5410085A (en) * | 1992-10-27 | 1995-04-25 | Bayer Aktiengesellschaft | Process for the preparation of chlorine-substituted aromatic amines and of catalysts |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1096444C (en) * | 1996-10-10 | 2002-12-18 | 常州市常宇化工厂 | Process for preparing menaphthyl amine by using crystallizing separating method |
| CN1052971C (en) * | 1998-03-13 | 2000-05-31 | 常州市常宇化工厂 | Industrial high-purity methyl naphthylamine and its preparation |
| WO2005055216A1 (en) * | 2003-12-04 | 2005-06-16 | Matsushita Electric Industrial Co., Ltd. | Optical information reproduction device |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB227481A (en) * | 1923-08-27 | 1924-12-29 | Gualtiero Poma | An improved process for the preparation of alphanaphthylamine |
| US3499034A (en) * | 1966-08-01 | 1970-03-03 | Du Pont | Hydrogenation of aromatic nitro compounds |
| DE2036313C3 (en) * | 1970-07-22 | 1982-03-25 | Bayer Ag, 5090 Leverkusen | Process for the preparation of halogen-substituted aromatic amines |
| DE2452015C2 (en) * | 1974-11-02 | 1984-01-12 | Bayer Ag, 5090 Leverkusen | Process for the production of diaminonaphthalene |
| DE2456308A1 (en) * | 1974-11-28 | 1976-08-12 | Bayer Ag | PROCESS FOR PRODUCING AMINO COMPOUNDS |
| DE2519838A1 (en) * | 1975-05-03 | 1976-11-11 | Bayer Ag | Catalyst for hydrogenation of nitro cpds. to amines - contg. palladium or platinum and opt. vanadium on a carrier |
-
1984
- 1984-09-11 DE DE19843433240 patent/DE3433240A1/en not_active Withdrawn
-
1985
- 1985-08-30 DE DE8585110919T patent/DE3561057D1/en not_active Expired
- 1985-08-30 EP EP85110919A patent/EP0174563B1/en not_active Expired
- 1985-09-06 JP JP60196110A patent/JPS6168451A/en active Granted
- 1985-09-09 CA CA000490275A patent/CA1241664A/en not_active Expired
- 1985-09-10 KR KR1019850006604A patent/KR920005379B1/en not_active IP Right Cessation
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5410085A (en) * | 1992-10-27 | 1995-04-25 | Bayer Aktiengesellschaft | Process for the preparation of chlorine-substituted aromatic amines and of catalysts |
Also Published As
| Publication number | Publication date |
|---|---|
| DE3561057D1 (en) | 1988-01-07 |
| JPH0246022B2 (en) | 1990-10-12 |
| EP0174563B1 (en) | 1987-11-25 |
| EP0174563A1 (en) | 1986-03-19 |
| JPS6168451A (en) | 1986-04-08 |
| KR920005379B1 (en) | 1992-07-02 |
| KR860002449A (en) | 1986-04-26 |
| DE3433240A1 (en) | 1986-03-20 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| USRE44175E1 (en) | Process for preparing 4-aminodiphenylamines | |
| US4792626A (en) | Production of aromatic diamino compounds using a modified Raney catalyst | |
| US4482741A (en) | Preparation of xylylenediamine | |
| US5739403A (en) | Process for the production of optionally substituted 4-aminodiphenylamines | |
| US4495369A (en) | Process for the preparation of neopentylamine | |
| EP0019454B1 (en) | Manufacture of toluene diamine | |
| EP0440829A1 (en) | Process for the preparation of N-substituted cyclic amines | |
| CN111217712A (en) | Method for preparing o-phenylenediamine from aniline | |
| CA1241664A (en) | Process for the preparation of 1-naphthylamine | |
| JP2002503246A (en) | Catalytic hydrogenation of nitrobenzene to 4-aminodiphenylamine in the presence of hydroxyl compounds and solvents | |
| CA1215724A (en) | Process for producing 4-alkoxyanilines | |
| CN115583895B (en) | Synthetic method of 2-amino-5-chloro-N, 3-dimethylbenzamide | |
| US6414192B1 (en) | Process for preparing 4-aminodiphenylamine | |
| US4426538A (en) | Process for the preparation of optionally p-chlorine-substituted 2,6-diaminotoluene | |
| JP3541396B2 (en) | Method for producing 4-aminodiphenylamine | |
| US3154584A (en) | Process for the catalytic reduction of dinitrotoluenes | |
| US3485875A (en) | Production of primary amines | |
| JPH06306020A (en) | Production of 4-aminodiphenylamine | |
| US4297512A (en) | Process for the preparation of triethylamine | |
| US3737462A (en) | Method for the preparation of 1,2-diaminopropane | |
| EP0537541B1 (en) | Process for the preparation of a mixture of cyclohexylamine and dicyclohexylamine | |
| US5811584A (en) | Preparation of tetramethylethylenediamine | |
| EP0992487A2 (en) | Process for the preparation of dicycloaliphatic amines | |
| US3205217A (en) | Hydrogenation process | |
| US3210426A (en) | Preparation of iminobisalkylamines |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEX | Expiry |