Process for producing a diarylamine

Details Process for producing a diarylamine Process for producing a diarylamine

2000-06-05

2001-04-17

Barts, Samuel (Department: 1621)

Organic compounds -- part of the class 532-570 series

Organic compounds

Amino nitrogen containing

C564S433000, C544S086000

Reexamination Certificate

active

06218576

ABSTRACT:

FIELD OF THE INVENTION
The present invention relates to a process for producing a diarylamine compound, which serves as an important intermediate in the production of organic photoconductors used for electrophotographs, organic electroluminescent devices or the like, dyestuffs, agricultural chemicals, pharmaceuticals and the like, in a high yield, at a high purity and at a low cost.
BACKGROUND OF THE INVENTION
It is the common practice to produce a diarylamine by the Ullmann condensation reaction of an aromatic halide and an arylamine derivative (Chem. Ber., 36, 2382(1902)), Chem. Ber., 40, 4541(1907)) or by subjecting an arylamine to self condensation or subjecting an arylamine and the corresponding arylamine hydrochloride to condensation reaction.
The production by the Ullman reaction is accompanied with the problems that the raw material aromatic halide is expensive and a step for hydrolyzing an amide formed by the condensation reaction is necessary.
In the condensation reaction of an arylamine, on the other hand, it was reported that a diphenylamine was available by heating of aniline and aniline hydrochloride to 300° C. in a solventless manner under a high pressure (Zeitschr. Chem., 438(1866)) and since then, addition of various effective catalysts have been proposed. For example, disclosed are a process of adding anhydrous ferrous chloride (U.S. Pat. No. 2,447,044), a process of adding ammonium chloride (U.S. Pat. No. 2,820,829), a process of adding anhydrous aluminum chloride and ammonium chloride (U.S. Pat. No. 2,645,662), a process of adding anhydrous ferrous chloride and ammonium bromide, and a process of adding cobalt chloride, stannous chloride, cupric chloride, zinc chloride, manganese chloride or the like, and ammonium chloride (U.S. Pat. No. 2,120,966).
In any one of the above-described processes, however, the reaction is conducted under severe conditions of 300 to 400° C. and a high pressure, which requires special equipment such as pressure reactor.
As processes comprising the reaction under a normal pressure, proposed are a process (Zh. Prikl. Khim. (Leningrag). Vol.9, 502(1936)) for synthesizing a diphenylamine by reacting aniline and aniline hydrochloride in the presence of aluminum chloride as a catalyst at 220 to 240° C. for 20 to 25 hours and a process for preparing di-p-tolylamine which comprises reacting p-toluidine in an aromatic solvent in the presence of anhydrous aluminum chloride and ammonium chloride (Unexamined published Japanese patent application No. Hei. 6-100504). These processes, however, need at least 15 hours to complete the reaction and in addition, the diarylamine obtained by each of these processes is not so highly pure as to be usable as an intermediate for the raw material of an electronic material.
SUMMARY OF THE INVENTION
An object of the present invention is to provide a process for producing a diarylamine in a high yield at a low cost which process does not require special equipment such as pressure reactor and can terminate the reaction in a short time even under a normal pressure.
Another object of the present invention is to provide a process for producing, at a low cost, a high-purity diarylamine sufficiently usable as an intermediate for the production of a raw material for an electronic material.
According to the present invention, there is thus provided the below-described process for producing a diarylamine and the object of the present invention is attained by the process.
That is, the present invention provides a process for producing a diarylamine, which comprises subjecting an arylamine to condensation reaction in the presence of anhydrous aluminum chloride and anhydrous calcium chloride.
DETAILED DESCRIPTION OF THE INVENTION
The present invention will hereinafter be described more specifically.
In the present invention, an arylamine as a substrate is preferably represented by the following general formula (I):
A—NH
2
  (I)
wherein A represents a substituted or an unsubstituted aryl group.
In formula (I), A is preferably a substituted or an unsubstituted phenyl group, and more preferably a methyl-substituted phenyl group.
In the production process of the present invention, both anhydrous aluminum chloride and anhydrous calcium chloride are used as a catalyst. The reaction in the presence of these catalysts makes it possible to markedly reduce the reaction time and increase the yield, compared with the reaction using a conventionally proposed catalyst. In addition, when these catalysts are employed, a diarylamine having a sufficiently high purity suited for use as an intermediate for the production of a raw material for an electronic material can be obtained by simple purification treatment.
When the reaction is conducted in the presence of one of these catalysts or another combination of catalysts, the reaction time increases and the yield considerably lowers.
Each of anhydrous aluminum chloride and anhydrous calcium chloride is preferably used in a molar ratio (catalyst/arylamine) ranging from 0.05 to 1.0, more preferably from 0.15 to 0.5, still more preferably from 0.20 to 0.35 relative to the arylamine. The molar ratio of anhydrous aluminum chloride to anhydrous calcium chloride (anhydrous aluminum chloride/anhydrous calcium chloride) preferably ranges from 0.2 to 3.0, more preferably from 0.5 to 2.2 and still more preferably from 0.8 to 1.9.
In the production process of the present invention, it is not necessary to use a reaction solvent. As a reaction solvent, however, an aromatic compound having a boiling point of higher than 189° C., preferably 190 to 250° C. or an aliphatic compound having a boiling point of higher than 189° C., preferably 190 to 250° C. is used as needed.
Examples of the aromatic compound having a boiling point of higher than 189° C. include:
(i) aromatic hydrocarbon compounds which may be halogenated, more specifically, diisopropylbenzene, 1-phenylhexane, 1,2-dichlorobenzene, 1,2,4-trichlorobenzene, 1,4-cyclohexylbenzene and diphenylmethane.
(ii) aromatic heterocyclic compounds, more specifically, 2,4-dichloropyrimidine, 2,3,5-trichloropyridine, quinoline, quinazoline and 1,4-benzodioxane.
(iii) aromatic hydrocarbon compounds having a cyclic skeleton which has been partially hydrogenated, for example, dihydrogenated, tetrahydrogenated, hexahydrogenated, octahydrogenated or decahydrogenated, more specifically, 1,4-dihydronaphthalene, 1,2,3,4-tetrahydronaphthalene, 9,10-dihydroanthracene, 9,10-dihydrophenanthrene, 4,5,9,10-tetrahydropyrene, 1,2,3,6,7,8-hexahydropyrene and dodecahydrotriphenylene.
(iv) hydrogenated aromatic heterocyclic compounds, more specifically, 1,2,3,4-tetrahydroquinoline, 5,6,7,8-tetrahydroquinoline, 1,2,3,4-tetrahydroisoquinoline, 5,6,7,8-tetrahydroisoquinoline, 1-phenylpiperidine, 1-phenylpiperazine, indoline and julolidine.
Examples of the aliphatic compound having a boiling point of higher than 189° C. include:
(v) saturated aliphatic compounds, more specifically, undecane, dodecane, tridecane, 2-methyldodecane, 4-ethylundecane, tetradecane, pentadecane, 3,3-dimethyltridecane, hexadecane, heptadecane, 2-methyl-4-ethyltetradecane.
(vi) unsaturated aliphatic compounds, more specifically, 1-undecene, 4-dodecene, 3,3-dimethyl-l-decene, 1,3,5-dodecatriene, 5-tridecene, 3-methyl-4-ethyl-2-decene, 1-dodecyne, 3-dodecen-1-yne, 1-tridecine, 5,5-dimethyl-3-undecen-1-yne and 5-ethynyl-1,3-dodecadiene.
(vii) saturated alicyclic compounds, more specifically, dicyclohexane, decahydronaphthalene and dodecahydrofluorene.
(viii) unsaturated alicyclic compounds, more specifically, cyclododecene, 1,5,9-cyclodecatriene, (−)-&bgr;-bisabolene, &agr;-humulene, &agr;-camphorene, cembrene, (−)-&bgr;-cadinene, (−)-&bgr;-caryophyllene, (−)-&bgr;-santalene, (−)-(&agr;-cedrene and (+)-&bgr;-selinene.
(ix) saturated aliphatic heterocyclic compounds, more specifically, 1,4,7-trithiacyclononane, 1,4,7-trithiacyclodecane, 1,4,7,10-tetraoxacyclododecane, 1,4,7,10,13-pentaoxacyclopentadecane, 1,4,7-triazacyclononane, 1,4,7,10-tetraazacyclododecane.
(x) unsa

Affiliated with

Also associated with

Rating

Process for producing a diarylamine does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Process for producing a diarylamine, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Process for producing a diarylamine will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2458188