JP3148556B2 - Method for producing 2-bisarylamino-9,9-dialkylfluorene - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a process for producing 2-bisarylamino-9,9-dialkylfluorene, which is important as an intermediate for dyes, drugs, high molecular monomers and the like.

[0002]

2. Description of the Prior Art 2-Bisarylamino-9,9-dialkylfluorene is the corresponding 9,9-dialkyl-2.
-Synthesized by an Ullmann reaction in which iodofluorene and a diarylamine are reacted under a metal catalyst. After completion of the Ullmann reaction, when a catalyst or the like is filtered off and the solvent is distilled off under reduced pressure to obtain a target product, a crystal of 2-bisarylamino-9,9-dialkylfluorene is not obtained. A tar-like substance containing impurities is obtained. Therefore, it is necessary to isolate and purify the desired product. However, the present inventors have already proposed a method for isolating 2-bisarylamino-9,9-dialkylfluorene from this tar-like substance by adding a surfactant. (Japanese Patent Laid-Open No. 5-1)
No. 25023). However, the obtained target product contained a tar component, and required further purification by recrystallization.

[0003]

The tar-like substance obtained by the Ullmann reaction in which the corresponding 9,9-dialkyl-2-iodofluorene is reacted with a diarylamine in the presence of a metal catalyst is the target product 2 -A mixture of bisarylamino-9,9-dialkylfluorene and high-boiling and low-polar by-products. As a result of detailed analysis of the tarry substance, the present inventors have found that a by-product is diiodo-substituted 9,9-dialkylfluorene which is contained as a by-product of 9,9-dialkyl-2-iodofluorene as one of the raw materials. (Hereinafter also referred to as a diiodo-substituted product), or a reaction product of a plurality of iodides of aromatic hydrocarbons contained as impurities and a diarylamine, and an oxidative decomposition product of another raw material, diarylamine. Was revealed this time.

An object of the present invention is to provide a method for producing 2-bisarylamino-9,9-dialkylfluorene from which the above-mentioned impurities have been removed.

[0005]

As a result of testing various methods to achieve the above object, it was found that 2-bisarylamino-9,9-dialkylfluorene was obtained in high yield and high purity by using a silica gel column method. Can be manufactured.

[0006] The present invention uses the formula

Embedded image (Where R represents a methyl, ethyl or propyl group) having a purity of 98% or more and a diiodo-substituted 9,9-diamine.
Alkyl-2-iodofluorene containing not more than 0.5% by weight
A 9,9-dialkyl-2-iodofluorene of the formula

Embedded image The reaction mixture obtained by reacting with the diarylamine represented by any of
Using an aliphatic hydrocarbon, 2-bisarylamino-
0.5 by weight with respect to 9,9-dialkylfluorene.
2-bisarylamino-, which is purified by silica gel column treatment using the silica gel of (1) to (5).
This is a method for producing 9,9-dialkylfluorene.

In the present invention, 9,9-dialkyl-2-
It is a preferred embodiment of the present invention to use iodofluorene having a purity of 98% or more and a diiodo-substituted product of 0.5% by weight or less.

In the present invention, the Ullmann reaction is usually carried out under normal pressure. Under these conditions, an inert organic solvent having a boiling point of 180 ° C. or higher is used. Specifically, o-dichlorobenzene, trichlorobenzene, undecane, dodecane, tridecane and the like are preferable, and o-dichlorobenzene and undecane are preferable. However, when performed under pressure, there is no limitation on the boiling point.

The amount of the solvent used is usually 0.5 to 10 times by weight, preferably 1 to 3 times by weight, based on the starting material 9,9-dialkyl-2-iodofluorene. Metallic copper powder is usually used as a catalyst, but shaved copper powder is preferable, and usually 0.1 to 5 mole ratio, preferably 0.2 to 3.0 mole ratio to 9,9-dialkyl-2-iodofluorene as a raw material. Use molar ratio. The reaction temperature is usually from 180 to 220C, preferably from 185 to 205C.

In the method of the present invention, after completion of the reaction, the catalyst and the like are separated by filtration, and the residual tar-like substance obtained after distilling off the solvent under reduced pressure is isolated by crystallization using various solvents if necessary. However, in this case, it is preferable to use an aprotic polar solvent.

Specifically, dimethyl sulfoxide, N,
Examples thereof include N-dimethylformamide and 1,3-dimethyl-2-imidazolidinone. Among them, N, N-dimethylformamide and 1,3-dimethyl-2-imidazolidinone are preferable.

The amount of the solvent used is preferably 9,9 of the raw material.
It is 0.5 to 10 times by weight, particularly preferably 0.5 to 3 times by weight, of -dialkyl-2-iodofluorene. 0.5
If the amount is less than the weight, tarification occurs, and if the amount exceeds 10 times, the yield tends to decrease. Further, the yield can be improved by adding methanol, ethanol or the like. Among them, methanol is preferred.

The amount of the solvent used is preferably 9,9 of the raw material.
-Dialkyl-2-iodofluorene is 0.4 to 10 times by weight, particularly preferably 0.5 to 5 times by weight. 2-bisarylamino-9,9- obtained by this crystallization
The dialkylfluorene is heated and dissolved in a linear aliphatic hydrocarbon, for example, hexane, heptane, octane, nonane, preferably hexane, heptane.

The amount of the solvent used is usually 1 to 10 times by weight, preferably 3 to 6 times by weight, based on the charged 2-bisarylamino-9,9-dialkylfluorene. If the amount is less than 1 time by weight, crystals may be precipitated. If the amount is more than 10 times by weight, the rate of removal of tar components decreases.

After dissolution, it is developed on a silica gel column which has been adjusted in advance. The amount of silica gel used is 2-
The bisarylamino-9,9-dialkylfluorene is dispersed in the same solvent as the above-mentioned dissolving solvent in an amount of usually 0.5 to 5 times by weight, preferably 1 to 3 times by weight. 0.5
When the weight is less than the weight, the removal rate of the tar component tends to decrease, while when the weight is 5 or more, the recovery tends to decrease. It is preferable to keep the temperature of the adjusted column at 30 to 60 ° C. This improves the recovery rate.

The 2-bisarylamino-9,9-dialkylfluorene solution is developed on a silica gel column usually in 2 to 10 parts, preferably in 3 to 6 parts. By dividing and charging, the amount of silica gel used can be reduced.

[0017]

EXAMPLES The present invention will be specifically described below with reference to examples.

Example 1 9,9-Dimethyl-2-iodofluorene (purity 99.
32 g (0.10 mol) of 5%, diiodo-substituted product 0%),
23.6 g (0.124 mol) of di-p-tolylamine,
6.4 g (0.10 mol) of copper powder and 80 ml of ODCB were mixed and reacted for 15 hours under reflux with heating. After the reaction,
Potassium carbonate and copper powder were separated by filtration, and ODCB was distilled off under reduced pressure to obtain 40 g of a tar-like reaction crude product. To this, 32 g of 1,3-dimethyl-2-imidazolidinone was added and dissolved by heating. Further, 32 g of methanol was added for crystallization. After crystallization, filtration and drying are performed.
9 g of 2-bis (4-methylphenyl) amino-9,9
-Dimethylfluorene was obtained. 140 g of hexane was added to the mixture, and the mixture was dissolved by heating, kept at 60 ° C., adjusted using 50 g of silica gel, and developed on a column kept at 40 ° C. The charging was carried out in four parts, each time developing with approximately 1 L of solvent. The developing solution was concentrated to dryness and recrystallized from 60 g of hexane to obtain 33.1 g of 2-bis (4-methylphenyl) amino-9,9-dimethylfluorene. 85.0% yield, melting point 140-141 ° C, HPLC purity 9
9.9%.

Example 2 9,9-Dimethyl-2-iodofluorene (purity 99.
32 g (0.10 mol) of 5%, diiodo-substituted product 0%),
23.6 g (0.124 mol) of di-p-tolylamine,
6.4 g (0.10 mol) of copper powder and 80 ml of ODCB were mixed and reacted for 15 hours under reflux with heating. After the reaction,
Potassium carbonate and copper powder were separated by filtration, and ODCB was distilled off under reduced pressure to obtain 40 g of a tar-like reaction crude product. To this was added 32 g of N, N-dimethylformamide, dissolved by heating, and further 64 g of methanol was added for crystallization. After crystallization, the mixture was filtered and dried to obtain 35.1 g of 2-bis (4-methylphenyl) amino-9,9-dimethylfluorene. To this, 175 g of heptane was added and dissolved by heating, kept at 60 ° C., adjusted using 52 g of silica gel, and developed on a column kept at 40 ° C. The charging was carried out in four parts, each time developing with approximately 1 L of solvent.
The developing solution was concentrated to dryness and recrystallized from 66 g of heptane to obtain 33.7 g of 2-bis (4-methylphenyl) amino-9,9-dimethylfluorene. 86.6 yield
%, Melting point 140-141 ° C, HPLC purity 99.9%.

Example 3 9,9-Diethyl-2-iodofluorene (purity 99.
17.4 g (0.05 mol), di-p-tolylamine 11.8 g (0.062 mol), copper powder 3.2 g (0.05 mol), ODCB 40 m
were mixed and reacted under heating and refluxing for 15 hours. After completion of the reaction, potassium carbonate and copper powder were separated by filtration, and ODC was
B was distilled off to obtain 19 g of a tar-like reaction crude product. To this, 35 g of N, N-dimethylformamide was added and dissolved by heating, and 35 g of methanol was further added for crystallization. After crystallization, the mixture was filtered and dried to obtain 19.5 g of 2-bis (4-methylphenyl) amino-9,9-diethylfluorene. 78 g of octane was added thereto to dissolve by heating, kept at 60 ° C., adjusted using 39 g of silica gel, and developed on a column kept at 40 ° C.
The charging was carried out in four parts, each time developing with approximately 1 L of solvent. The developing solution was concentrated to dryness and recrystallized from 30 g of octane to obtain 18.1 g of 2-bis (4-methylphenyl) amino-9,9-dimethylfluorene. Yield 80.
4%, melting point 113 ° C, HPLC purity 99.9%.

Example 4 9,9-dibutyl-2-iodofluorene (purity 99.
18.8 g (0.05 mol), di-p-tolylamine 11.8 g (0.05 mol), copper powder 3.2 g (0.05 mol), ODCB 40 m
were mixed and reacted under heat reflux for 20 hours. After completion of the reaction, potassium carbonate and copper powder were separated by filtration, and ODC was
B was distilled off to obtain 21 g of a tar-like crude reaction product. N, N-dimethylformamide (19 g) was added thereto and dissolved by heating, and methanol (38 g) was further added for crystallization. After crystallization, 19.1 g of 2-bis (4-methylphenyl) amino-9,9-diethylfluorene was obtained by filtration and drying. 80 g of hexane was added thereto to dissolve by heating, kept at 60 ° C., adjusted using 30 g of silica gel, and developed on a column kept at 40 ° C.
The charging was carried out in four parts, each time developing with approximately 1 L of solvent. The developing solution was concentrated to dryness and recrystallized from 40 g of hexane to obtain 18.0 g of 2-bis (4-methylphenyl) amino-9,9-dimethylfluorene. Yield 80.
9%, melting point 102 [deg.] C, HPLC purity 99.9%.

Examples 5 to 10 Bisaryl-9,9-dialkylfluorenes having respective substituents were synthesized according to Example 1 and purified by a silica gel column. The results are shown in Table 1.

[0023]

[Table 1]

[0024]

[Table 2]

[0025]

According to the method of the present invention, 2-bisarylamino-9,9-dialkylfluorene can be obtained with high yield and high purity.

Continuation of the front page (56) References JP-A-6-192188 (JP, A) JP-A-5-125023 (JP, A) JP-A-8-268980 (JP, A) The Chemical Society of Japan, 4th Edition Experiment Chemistry Course 1 Basic Operation I, pp. 288-291 Published November 5, 1990 (Maruzen Co., Ltd.) (58) Fields investigated (Int. Cl. ⁷ , DB name) C07C 211/61 C07C 209 / 10 C07C 213/02 C07C 217/92 CA (STN) REGISTRY (STN)

Claims (1)

(57) [Claims] (1) Formula (1) (Where R represents a methyl, ethyl or propyl group) having a purity of 98% or more and a diiodo-substituted 9,9-diamine.
Alkyl-2-iodofluorene containing not more than 0.5% by weight
And 9,9-dialkyl-2-iodo-fluoren those of the formula ## STR2 ## The reaction mixture obtained by reacting with the diarylamine represented by any of
Using an aliphatic hydrocarbon, 2-bisarylamino-
0.5 by weight with respect to 9,9-dialkylfluorene.
2-bisarylamino-, which is purified by silica gel column treatment using the silica gel of (1) to (5).
A method for producing 9,9-dialkylfluorene.