CN1105661A

CN1105661A - 2-cyano-4-nitroaniline synthetic process

Info

Publication number: CN1105661A
Application number: CN 94110826
Authority: CN
Inventors: 王旗
Original assignee: Individual
Current assignee: Individual
Priority date: 1994-01-21
Filing date: 1994-01-21
Publication date: 1995-07-26

Abstract

The present invention relates to a new technological process for synthesizing a main raw material for producing disperse dyes -2-cyano-4-nitrophenylamine. It uses 2-chloro-5-nitrobenzonitrile as raw material, uses high-concentration ammonia liquor as medium, its controlled reaction temp. is 55-95 deg.C, take-hold pressure is 9-14 kgf/cm2, and its reaction time is 2-7 h., so that the invented product can be obtained, and its yield is 95.7% and its product content is 98%. Said technological process is stable in reaction, safe, easy to control, low in cost, high in yield and purity, and can greatly raise the quality of synthetic dispense dyes.

Description

2-cyano-4-nitroaniline synthetic process

The present invention is a kind of important source material 2 cyano 4 nitro aniline new synthetic process of producing dispersed dye.

2 cyano 4 nitro aniline is the important source material of synthetic dispersed dye, usually be that raw material is through the synthetic o-chloro benzonitrile of ammonia oxidation with the ortho-chlorotolu'ene, again through nitrated and 2-chloro-5-p-nitrile, again with 2-chloro-5-p-nitrile through ammonification and the product 2 cyano 4 nitro aniline.The past aminating reaction adopts organic solvent as medium, and not only yield is low, cost is high, and contaminate environment, harmful HUMAN HEALTH.External existing carry out aminating reaction as reaction medium with ammoniacal liquor, as Czech patents: 246956, its is with the ammoniacal liquor of 25-45% concentration, and temperature of reaction is 98-110 ℃, at 10-11kgf/cm ²Pressure is reaction down, and obtaining yield is 94%, the 2 cyano 4 nitro aniline of content 98%, and this method temperature height is wayward.German Patent DD274416 and for example, it makes medium with 25% ammoniacal liquor, and adds C ₁₂-C ₁₈Alkyl sodium sulfonate, temperature of reaction is 100 ℃, reacts under the 3-4 bar pressure, obtaining yield is 92%, content is 91.5% 2 cyano 4 nitro aniline, this method yield and content are lower, can not be satisfactory.Chinese patent 92111757.4; It adopts C with water as medium ₁₂-C ₁₈Alkyl benzene sulphonate (ABS) or its sodium salt are made phase-transfer catalyst, and temperature of reaction is 75-97 ℃, feed ammonia pressurization ammonification under constantly stirring, and keep pressure at 8-10kgf/cm ², obtaining 2 cyano 4 nitro aniline, this method has been got rid of the ammoniacal liquor preparation process, simplify the operation, temperature of reaction and pressure are lower, the yield height, but its weak point is a long reaction time, and, make the products obtained therefrom filtration difficulty owing to add the emulsifying effect of catalyzer, be difficult to washing again, simultaneously because the foaming effect of catalyzer, the superfine raw material is formed hydrazine by degree of depth ammonification, causes the product content instability, must further improve technology.

The objective of the invention is existing CN92111757.4 patent is carried out process modification, provide a kind of and need not add that phase-transfer catalyst, yield height, product content height, technology are simple, the 2 cyano 4 nitro aniline new synthetic process of reacting balance.

The present invention is achieved in that by 2-chloro-5-p-nitrile through ammonification Synthetic 2-cyano-4-nitroaniline, its reaction formula is as follows:

Its technological process: with 2-chloro-5-p-nitrile is raw material, with the 46-70%(weight percentage) the high strength ammonia water as medium, under constantly stirring, the intensification control reaction temperature is kept reaction pressure at 9-14kgf/cm at 55-95 ℃ ², reacted 2-7 hour and 2 cyano 4 nitro aniline.Its yield is 95.7%, and content is 98%.

New synthetic process of the present invention, be perfect to the further improvement of CN92111757.4 patent, owing to do not add alkylbenzene sulfonate, the yield that has overcome it emulsification causes to product is on the low side, filtration difficulty, be difficult to shortcomings such as the washing and the caused degree of depth ammonification of foaming again, owing to adopt high density ammoniacal liquor, low reaction temperatures, make reacting balance and be easy to control, side reaction is few, make the product content height, the yield height.High density ammoniacal liquor is directly to be made into desired concn in the reaction under high pressure pot, stops logical ammonia then, is warming up to temperature of reaction, keeps certain pressure and reacts, and has saved the trouble of continuously logical ammonia in the former method reaction process, makes technology more simple.The product yield height that this law is produced can reach 95.7%, and content is also high, can reach 98%, save energy.Because the product purity height can make synthetic dispersed dye quality improve greatly, has shown the superiority of this law.

Technical process of the present invention is as follows:

Below the present invention is described in further detail:

2 cyano 4 nitro aniline is one of important source material of producing dispersed dye, it generally adopts with the ortho-chlorotolu'ene is that raw material is through the synthetic o-chloro benzonitrile of ammonia oxidation, again through the nitrated 2-chloro-5-p-nitrile that obtains, again with 2-chloro-5-p-nitrile ammonification Synthetic 2-cyano-4-nitroaniline, the present invention improves the ammonification technology of CN92111757.4 patent, with 2-chloro-5-p-nitrile is raw material, improve ammonia concn, reduce temperature of reaction, so that react completely with reacting balance, benzene sulfonamide acid groups tensio-active agent is added in cancellation, to overcome filtration difficulty, be difficult to the shortcoming of washing again, with the high strength ammonia water as medium, according to ammonia at certain pressure, solubility curve under the temperature, its the best ammonia concn of ammoniacal liquor that directly is mixed with 46-70% concentration in the reaction under high pressure pot is 46-55%, stopping logical ammonia then heats up under constantly stirring, control reaction temperature is at 55-95 ℃, and its optimal reaction temperature is 80-90 ℃, keeps reaction pressure at 9-14kgf/cm ², to react 2-7 hour, reaction finishes, cools off, filters, cleans, dries and makes the 2 cyano 4 nitro aniline finished product, and its yield is 95.7%, and product content is 98%.

Embodiment 1:

Add 138 parts of 2-cyano group-5-p-nitriles in the reaction under high pressure pot, 270 parts of water start stirring, at room temperature feed ammonia, make ammonia concn reach 47%, stop logical ammonia, are warming up to 75-80 ℃, keep pressure at 9-13.5kgf/cm ², reacted 5 hours, reaction finishes, and is cooled to room temperature, filter, water filter wash and to neutral, dry finished product, yield is 95.7%, product content is 98.2%, fusing point is 208-209 ℃.

Embodiment 2:

Add 150 parts of 2-chloro-5-p-nitriles in the reaction under high pressure pot, 300 parts of water start stirring, at room temperature feed ammonia, make ammonia concn reach 50%, stop logical ammonia, are warming up to 85 ℃, and insulation is kept pressure at 9-13kgf/cm ², reacted 5 hours, reaction finishes, and is cooled to room temperature, filters, and washes with water to neutrality, dry finished product, yield is 93%, product content is 96.5%, fusing point is 206-208 ℃.

Embodiment 3:

Add 150 parts of 2-chloro-5-p-nitriles in the reaction under high pressure pot, 450 parts of water start stirring, at room temperature feed ammonia, make ammonia concn reach 50%, stop logical ammonia, are warming up to 90-95 ℃, and insulation is kept pressure at 10-13kgf/cm ², reacted 2 hours, pressure relief is cooled to room temperature, filters, and washes with water to neutrality, dry finished product, yield is 92.8%, product content is 94%, fusing point is 202-205 ℃.

Embodiment 4:

Add 150 parts of 2-chloro-5-p-nitriles in the reaction under high pressure pot, 450 parts of water start stirring, at room temperature feed ammonia, make ammonia concn reach 60%, stop logical ammonia, are warming up to 80-90 ℃, react 6 hours, keep pressure at 10-13kgf/cm ², reaction finishes, pressure relief is cooled to room temperature, filters, and washes with water to neutrality, dry finished product, yield is 80%, product content is 96%, fusing point is 204-206 ℃.

Claims

1, a kind of new synthetic process of producing the important source material 2 cyano 4 nitro aniline of dispersed dye, it is that raw material gets 2 cyano 4 nitro aniline through ammonification with 2-chloro-5-p-nitrile, it is characterized in that it is with 46--70% (weight percentage) high strength ammonia water as medium, under constantly stirring, the intensification control reaction temperature is kept reaction pressure at 9-14kgf/cm at 55-95% ², reacted 2-7 hour, and get 2 cyano 4 nitro aniline.

2, new synthetic process according to claim 1 is characterized in that ammonia concn is with the 46-55%(weight percentage) be optimum value.

3, new synthetic process according to claim 1 is characterized in that temperature of reaction is an optimum value with 80-90 ℃.