JP2005263737A - Formylated triphenylamine derivative and method for producing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a formylated amine stilbene derivative suitable as a starting material for an amine stilbene derivative having specific drum sensitivity properties owing to bearing predetermined substituents on predetermined sites in the molecule, and to provide a method for producing the formylated amine stilbene derivative. <P>SOLUTION: The method for producing the formylated amine stilbene derivative of the general formula(1)[wherein, each of a plurality of R<SP>1</SP>to R<SP>10</SP>are each independently H, a halogen atom, (un)substituted 1-20C alkyl, (un)substituted 1-20C alkoxy, (un)substituted 6-20C aryl or (un)substituted amino group] comprises formylating a predetermined triphenylamine derivative by Vilsmeier process. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a formylated triphenylamine derivative and a method for producing the same, and in particular, a starting material (intermediate) of an amine stilbene derivative having a predetermined drum sensitivity characteristic by having a predetermined substituent at a predetermined position in the molecule. The present invention relates to a suitable formylated triphenylamine derivative and a method for producing the same.

Conventionally, as an electrophotographic photosensitive member for an image forming apparatus or the like, an organic photosensitive member made of an organic photosensitive material such as a charge transporting agent, a charge generating agent, and a binder resin (binder resin) has been used. Such an organic photoreceptor is advantageous in that it is easy to manufacture and has a wide degree of freedom in structural design because it has various options for the photoreceptor material as compared with conventional inorganic photoreceptors.
Among such organic photoreceptor materials, as a charge transport agent having a bulky group in the molecule, high compatibility with the binder resin, and having a high charge transport ability (hole transport ability), the following general formula An amine stilbene derivative represented by (7) is proposed.

(In General Formula (7), a plurality of R ^{1 to} R ¹⁴ are each independently a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted group having 1 to 20 carbon atoms, or An unsubstituted alkoxy group, a substituted or unsubstituted aryl group having 6 to 20 carbon atoms, or a substituted or unsubstituted amino group.)

However, the formylated triphenylamine derivative used as a raw material for such an amine stilbene derivative generally has a problem of low yield. That is, the proposed amine stilbene derivative has a problem that the production cost is high despite having a high charge mobility.
Accordingly, the present inventors can produce a high yield by using a predetermined formylated triphenylamine derivative, and as a result, the amine stilbene derivative represented by the general formula (7) is inexpensive. The present inventors have found the fact that they can be manufactured and have completed the present invention.
That is, an object of the present invention is to provide a formylated triphenylamine derivative suitable as a starting material (intermediate) of an amine stilbene derivative represented by the general formula (7), and a method for producing the same.

  According to the present invention, a formylated triphenylamine derivative represented by the following general formula (1) is provided, and the above-mentioned problems can be solved.

(In General Formula (1), a plurality of R ^{1 to} R ¹⁰ are each independently a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted group having 1 to 20 carbon atoms, or An unsubstituted alkoxy group, a substituted or unsubstituted aryl group having 6 to 20 carbon atoms, or a substituted or unsubstituted amino group.)

Further, in constituting the formylated triphenylamine derivative of the present invention, the general formula ⁽¹⁾ R 1 ~R ¹⁰ in is preferably a hydrogen atom or an alkyl group having 1 to 6 carbon atoms.

  Another embodiment of the present invention is a process for producing a formylated triphenylamine derivative represented by the following reaction formula (1), wherein the triphenylamine derivative represented by the general formula (2) is converted to Vilsmeier. This is a method for producing a formylation triphenylamine derivative characterized in that it is formylated by the (Vilsmeier) method.

(In the reaction formula (1), a plurality of R ^{1 to} R ¹⁰ are each independently a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted group having 1 to 20 carbon atoms, or An unsubstituted alkoxy group, a substituted or unsubstituted aryl group having 6 to 20 carbon atoms, or a substituted or unsubstituted amino group.)

  In carrying out the method for producing the formylated triphenylamine derivative of the present invention, as represented by the following reaction formula (2), the triphenylamine derivative represented by the general formula (2) is represented by the general formula (3 The aniline derivative represented by the general formula (4) is reacted with iodobenzene to obtain the triphenylamine compound represented by the general formula (4), followed by formylation by the Vilsmeier method. It is preferable to use a triphenylamine derivative obtained by reacting a formylated triphenylamine compound represented by the formula (5) and a phosphorus ylide derivative represented by the general formula (6) with a Wittig reaction. .

(In the reaction formula (2), the plurality of R ^{1 to} R ¹⁰ are the same as those in the reaction formula (1).)

  Moreover, when implementing the manufacturing method of the formylation triphenylamine derivative of this invention, it is preferable to react a phosphorus ylide derivative etc. in presence of a catalyst in the case of a Wittig reaction.

  Moreover, when implementing the manufacturing method of the formylation triphenylamine derivative of this invention, it is preferable to use alkyllithium as a catalyst in the Wittig reaction.

  According to the present invention, a formylated triphenylamine derivative represented by the general formula (1) can be provided. Therefore, by using Wittig reaction as a starting material, general formula (7) having a bulky group in the molecule, high compatibility with the binder resin, and high charge transport ability (hole transport ability) The represented amine stilbene derivative can be produced with high yield.

Further, according to the formylated triphenylamine derivative of the present invention, R ^{1 to} R ¹⁰ in the general formula (1) are hydrogen atoms or alkyl groups having 1 to 6 carbon atoms. The amine stilbene derivative represented by the general formula (7), which is further excellent in compatibility with the resin and has high charge mobility and excellent charge injectability from the charge generator, is produced in high yield. be able to.

  Further, according to the method for producing a formylated triphenylamine derivative of the present invention, a formylated triphenylamine derivative having a predetermined structure is obtained by formylation by a Filsmeier method using a triphenylamine derivative having a predetermined structure as a starting material. High yield can be obtained. That is, since a triphenylamine derivative having a predetermined structure has two substituted phenyl groups at the styryl tip, only a selective position can be formylated due to their steric hindrance. Triphenylamine derivative can be obtained in high yield.

  Further, according to the method for producing a formylated triphenylamine derivative of the present invention, a forphenylated triphenylamine compound having a predetermined structure and a phosphorus ylide derivative having a predetermined structure are subjected to a Wittig reaction to thereby obtain a triphenylamine derivative having a predetermined structure. Can be obtained in high yield. Therefore, by using the obtained triphenylamine derivative, a formylated triphenylamine derivative having a predetermined structure can be obtained in a high yield by the Filsmeier method.

  Further, according to the method for producing a formylated triphenylamine derivative of the present invention, a formylation is performed by causing a Wittig reaction between a formylated triphenylamine compound having a predetermined structure and a phosphorus ylide derivative having a predetermined structure in the presence of a catalyst. A diphenyl structure can be efficiently introduced to an aldehyde group in a triphenylamine compound via an olefin group. Therefore, a formylated triphenylamine derivative having a specific structure can be efficiently produced.

  In addition, according to the method for producing a formylated triphenylamine derivative of the present invention, a formyl triphenylamine compound having a predetermined structure and a phosphorus ylide derivative having a predetermined structure are subjected to a Wittig reaction in the presence of alkyllithium, whereby formyl is obtained. The diphenyl structure can be introduced more efficiently through the olefin group with respect to the aldehyde group in the triphenylamine compound. Therefore, a formylated triphenylamine derivative having a specific structure can be produced more efficiently.

  Hereinafter, embodiments relating to the formylated triphenylamine derivative of the present invention and the production method thereof will be specifically described.

[First embodiment]
The first embodiment is a formylated triphenylamine derivative represented by the following general formula (1). In addition, R < ¹ > -R < ¹⁰ > in General formula (1) is the definition already mentioned above.

  Here, as a compound example of the formylated triphenylamine derivative represented by the general formula (1), a formylated triphenylamine derivative represented by the following formula (14) is shown.

[Second Embodiment]
The second embodiment is a method for producing a formylated triphenylamine derivative represented by the following reaction formula (1), wherein the triphenylamine derivative represented by the general formula (2) is converted to Vilsmeier. This is a method for producing a formylated triphenylamine derivative represented by the general formula (1), characterized in that it is formylated by a method.
In addition, a plurality of R ^{1 to} R ¹⁰ in the reaction formula (1) are the contents defined in the description of the general formula (1) unless otherwise specified.

1. Synthesis of Triphenylamine Derivative The triphenylamine derivative represented by the general formula (2) as a starting material in the reaction formula (1) has the first to third steps as shown in the following reaction formula (2). In addition, it can be synthesized using the Filsmeier method and the Wittig reaction.
That is, as the first step, the aniline derivative represented by the general formula (3) is reacted with iodobenzene to obtain the triphenylamine compound represented by the general formula (4).
Next, as a second step, a formylated triphenylamine compound represented by the general formula (5) is obtained from the obtained triphenylamine compound represented by the general formula (4) by the Filsmeier method.
Next, as a third step, the obtained formylated triphenylamine compound represented by the general formula (5) and the phosphorus ylide derivative represented by the general formula (6) are subjected to a Wittig reaction to obtain a general formula (2) A triphenylamine derivative represented by the following formula is synthesized.
In addition, a plurality of R ^{1 to} R ¹⁰ in the reaction formula (2) are the contents defined in the description of the general formula (1) unless otherwise specified.

(1) First Step In the first step, when the aniline derivative represented by the general formula (3) is reacted with iodobenzene, the addition ratio is within a range of 1: 2 to 1: 4 in terms of molar ratio. It is preferable to set the value of.
The reason for this is that when the ratio of the aniline derivative and iodobenzene added is less than 1: 2.0, the amount of triphenylamine derivative that is the target product may be reduced. On the other hand, when the addition ratio of the aniline derivative and iodobenzene exceeds 1: 4, a large amount of unreacted iodobenzene remains, which may make it difficult to purify the target triphenylamine derivative. Because.
Therefore, the addition ratio of the aniline derivative represented by the general formula (3) and iodobenzene is more preferably set to a value in the range of 1: 2.1 to 1: 3.5 in terms of molar ratio. : It is more preferable to set it as the value within the range of 2.2-1: 3.

In the first step, when the aniline derivative represented by the general formula (3) is reacted with iodobenzene, the reaction temperature is usually set to a value within the range of 160 to 220 ° C., and the reaction temperature is 4 It is preferable to set the value within a range of ˜30 hours.
This is because, under such reaction conditions, a desired reaction can be efficiently performed using a relatively simple manufacturing facility.

(2) Second Step Next, in the second step, the Filsmeier method is carried out, and from the triphenylamine compound represented by the general formula (4), the formylated triphenylamine represented by the general formula (5) In obtaining a compound, it is preferable to carry out at the temperature of 130 degrees C or less, and to make reaction time into the value within the range of 2 to 5 hours.
This is because the desired reaction efficiency can be obtained using a relatively simple manufacturing facility under such reaction conditions.

In the second step, it is preferable to use a combination of the following compounds (i) and (ii) as the Filsmeier reagent when carrying out the Filsmeier method.
(i) Halogenating agents such as phosphorus oxychloride, phosgene, oxalyl chloride, thionyl chloride, triphenylphosphine-bromine, hexachlorotriphosphazatriene
(ii) N, N-dimethylformamide (DMF), N-methylformanilide (MFA), N-formylmorpholine, N, N-diisopropylformamide In the present invention, as the Filsmeier reagent, phosphorus oxychloride and a solvent A combination with DMF that can also be used as

In the preparation of the Vilsmeier reagent, the ratio of the compounds (i) and (ii) used is usually a molar ratio, preferably within a range of 1: 1 to 1:20. A value in the range of 1: 5 is more preferable.
Furthermore, with respect to the amount of the Filsmeyer reagent used, it is preferably set to a value within the range of 0.9 to 2 times the molar amount relative to 1 mol of the triphenylamine derivative represented by the general formula (5). A value within the range of 1.1 times the molar amount is more preferable.

(3) Third Step Next, as the third step, when the Wittig reaction is performed between the formylated triphenylamine compound represented by the general formula (5) and the phosphorus ylide derivative represented by the general formula (6), It is preferable that the temperature is usually a value in the range of −10 to 30 ° C. and the reaction time is a value in the range of 1 to 12 hours.
This is because the desired reaction efficiency can be obtained using a relatively simple manufacturing facility under such reaction conditions.

  Moreover, as a suitable solvent used for the Wittig reaction between the formylated triphenylamine compound represented by the general formula (5) and the phosphorus ylide derivative represented by the general formula (6), the reaction is not affected. Examples thereof include ethers such as diethyl ether, tetrahydrofuran and dioxane; halogenated hydrocarbons such as methylene chloride, chloroform and dichloroethane; and aromatic hydrocarbons such as benzene and toluene.

Examples of the catalyst used in the Wittig reaction include monovalent alkyllithium such as n-butyllithium, sec-butyllithium, and t-butyllithium, dilithiomethane, 1,4-dilithiobutane, and 1,6-dilithio. Suitable examples include divalent alkyl lithiums such as hexane, sodium alkoxides such as sodium methoxide and sodium ethoxide, and metal hydrides such as sodium hydride and potassium hydride.
In addition, it is more preferable to use alkyl lithium since the conversion efficiency is higher and the product is easily purified.

Here, it is preferable to make the addition amount of this base into the value within the range of 1.1-1.2 mol with respect to 1 mol of formylated triphenylamine compounds represented by General formula (5).
The reason for this is that when the amount of the base added is less than 1.1 mol, the formylated triphenylamine compound represented by the general formula (5), the phosphorus ylide derivative represented by the general formula (6), This is because the reactivity during the process may be significantly reduced.
On the other hand, when the amount of the base added exceeds 1.2 mol, Wittig between the formylated triphenylamine compound represented by the general formula (5) and the phosphorus ylide derivative represented by the general formula (6). This is because it may be extremely difficult to control the reaction.

In carrying out the Wittig reaction between the formylated triphenylamine compound represented by the general formula (5) and the phosphorus ylide derivative represented by the general formula (6), the addition ratio was 1: 3 in molar ratio. A value within the range of ˜3: 1 is preferable.
This is because when the ratio of the formylated triphenylamine compound and the phosphorus ylide derivative is less than 1: 3, a large amount of unreacted phosphorus ylide derivative may remain. On the other hand, when the addition ratio exceeds 3: 1, a large amount of unreacted formylated triphenylamine compound remains, which may make purification difficult.
Therefore, the addition ratio of the formylated triphenylamine compound represented by the general formula (5) and the phosphorus ylide derivative represented by the general formula (6) is within a range of 1: 2 to 2: 1 in terms of molar ratio. More preferably, the value of

2. Synthesis of formylated triphenylamine derivative The obtained triphenylamine derivative represented by the general formula (2) is formylated by the Filsmeier method, and the formylated triphenylamine derivative represented by the general formula (1) is obtained. Can be obtained.
The conditions of the Filsmeier method are the same as the reaction temperature and reaction time in the Filsmeier method as described in the second step for obtaining the triphenylamine derivative represented by the general formula (2). Is preferred.

[Third Embodiment]
The third embodiment relates to a method for using the formylated triphenylamine derivative represented by the general formula (1), and is represented by the general formula (1) as represented by the following reaction formula (3). An amine stilbene derivative represented by the general formula (7) can be synthesized from the formylated triphenylamine derivative, and an electrophotographic photoreceptor constituted by using the same.

(In the reaction formula (3), a plurality of R ^{1 to} R ¹⁴ are each independently a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted group having 1 to 20 carbon atoms, or An unsubstituted alkoxy group, a substituted or unsubstituted aryl group having 6 to 20 carbon atoms, or a substituted or unsubstituted amino group.)

1. Synthesis of Amine Stilbene Derivative Represented by General Formula (7) (1) Reaction Temperature and Reaction Time Also, as shown by Reaction Formula (3), a formylated triphenylamine derivative represented by General Formula (1) And a diphosphate derivative represented by the general formula (8) are subjected to a Wittig reaction to synthesize an amine stilbene derivative represented by the general formula (7).
In that case, it is preferable to make reaction temperature into the value within the range of -10-30 degreeC normally, and to make the reaction time into the value within the range of 1-12 hours.

(2) Solvent As a suitable solvent used for the Wittig reaction between the formylated triphenylamine derivative represented by the general formula (1) and the diphosphate derivative represented by the general formula (8), Any substance that does not affect the reaction may be used. Examples thereof include ethers such as diethyl ether, tetrahydrofuran and dioxane; halogenated hydrocarbons such as methylene chloride, chloroform and dichloroethane; and aromatic hydrocarbons such as benzene and toluene. It is done.

(3) Base As the base used for such a reaction, sodium alkoxide such as sodium methoxide and sodium ethoxide, and metal hydride such as sodium hydride and potassium hydride are preferable.
Here, it is preferable to make the addition amount of this base into the value within the range of 1.1-1.2 mol with respect to 1 mol of formylated triphenylamine derivatives.
The reason for this is that when the amount of the base added is less than 1.1 mol, the formylated triphenylamine derivative represented by the general formula (1) and the diphosphate ester derivative represented by the general formula (8) This is because the reactivity between and may be significantly reduced.
On the other hand, when the added amount of the base exceeds 1.2 mol, the formylated triphenylamine derivative represented by the general formula (1) and the diphosphate ester derivative represented by the general formula (8) This is because it may be extremely difficult to control the Wittig reaction.

(4) Addition ratio In carrying out the Wittig reaction between the formylated triphenylamine derivative represented by the general formula (1) and the diphosphate derivative represented by the general formula (8), the addition ratio is The molar ratio is preferably in the range of 2: 1 to 4: 1.
This is because when the ratio of the formylated triphenylamine derivative and the diphosphate derivative is less than 2: 1, a large amount of unreacted diphosphate derivative may remain.
On the other hand, when the addition ratio exceeds 4: 1, the unreacted formylated triphenylamine derivative may make purification difficult.
Therefore, the addition ratio of the formylated triphenylamine derivative represented by the general formula (1) and the diphosphate derivative represented by the general formula (8) is 2.2: 1 to 3: 1 in molar ratio. It is more preferable to set the value within the range.

2. Electrophotographic photosensitive member An electrophotographic photosensitive member provided with a photosensitive layer on a conductive substrate, wherein the photosensitive layer is represented by a formylated triphenylamine derivative represented by the general formula (1) and a general formula (8). An electrophotographic photoreceptor comprising an amine stilbene derivative represented by the general formula (7) obtained from a Wittig reaction with a diphosphate ester derivative.
There are single-layer type and multi-layer type electrophotographic photoreceptors, and the amine stilbene derivative of the present invention can be applied to both.
However, it can be used for both positive and negative charge types, has a simple structure and is easy to manufacture, can suppress film defects when forming layers, has few interface between layers, and can improve optical characteristics, etc. From the viewpoint, it is preferably applied to a single layer type.

(1) Single-layer Type Photoreceptor As shown in FIG. 1A, the single-layer type photoreceptor 10 has a single photosensitive layer 14 provided on a conductive substrate 12.
For example, the photosensitive layer includes an amine stilbene derivative (hole transport agent) represented by the general formula (1), a charge generator, a binder resin, and, if necessary, an electron transport agent in a suitable solvent. It can be formed by dissolving or dispersing and applying the resulting coating solution onto a conductive substrate and drying. Such a single layer type photoreceptor is characterized in that it can be applied to either a positive or negative charge type with a single configuration, has a simple layer configuration, and is excellent in productivity.
In addition, since the obtained single-layer type photoreceptor contains the amine stilbene derivative represented by the general formula (1), the residual potential is lowered and it has a predetermined sensitivity. is there.

Examples of the charge generating agent used in the single layer type photoreceptor include metal-free phthalocyanine, oxotitanyl phthalocyanine, perylene pigment, bisazo pigment, dithioketopyrrolopyrrole pigment, metal-free naphthalocyanine pigment, metal naphthalocyanine pigment, and square. Examples thereof include line pigments, trisazo pigments, indigo pigments, azurenium pigments, cyanine pigments, and the like alone or in combination of two or more.
Examples of the electron transport agent used in the single layer type photoreceptor include various compounds having high electron transport ability.
Examples of the binder resin used for the single layer type photoreceptor include styrene-butadiene copolymer, styrene-acrylonitrile copolymer, styrene-maleic acid copolymer, acrylic copolymer, styrene-acrylic acid copolymer. Polymer, polyethylene resin, ethylene-vinyl acetate copolymer, chlorinated polyethylene resin, polyvinyl chloride resin, polypropylene resin, ionomer resin, vinyl chloride-vinyl acetate copolymer, polyester resin, alkyd resin, polyamide resin, polyurethane resin , Polycarbonate resin, polyarylate resin, polysulfone resin, diallyl phthalate resin, ketone resin, polyvinyl butyral resin, polyether resin, polyester resin, etc .; silicone resin, epoxy resin, phenol resin, urea resin, melamine Fat, other crosslinking thermosetting resins, epoxy acrylates, urethane - photocurable resins such as acrylate can be used.

  In the case of a single layer type photoreceptor, the charge generating agent may be blended in an amount of 0.1 to 50 parts by weight, preferably 0.5 to 30 parts by weight with respect to 100 parts by weight of the binder resin. What is necessary is just to mix | blend the amine stilbene derivative (hole transport agent) of this invention in the ratio of 20-500 weight part with respect to 100 weight part of binder resin, Preferably it is 30-200 weight part. When the electron transport agent is contained, the ratio of the electron transport agent is 5 to 100 parts by weight, preferably 10 to 80 parts by weight with respect to 100 parts by weight of the binder resin.

Further, the thickness of the photosensitive layer in the single-layer type photoreceptor is 5 to 100 μm, preferably 10 to 50 μm.
As the conductive substrate on which such a photosensitive layer is formed, various materials having conductivity can be used, for example, iron, aluminum, copper, tin, platinum, silver, vanadium, molybdenum, chromium, Examples thereof include metals such as cadmium, titanium, nickel, palladium, indium, stainless steel, and brass, plastic materials on which the above metal is vapor-deposited or laminated, glass coated with aluminum iodide, tin oxide, indium oxide, and the like.

  Further, regarding the configuration of the single-layer type photoreceptor 10, as shown in FIG. 1B, a barrier layer 16 is formed between the conductive substrate 12 and the photosensitive layer 14 in a range that does not impair the characteristics of the photoreceptor. It may be. Further, as shown in FIG. 1C, a protective layer 18 may be formed on the surface of the photosensitive layer 14.

(2) Multilayer Photoreceptor Further, as shown in FIG. 2A, the multilayer photoreceptor 20 is a charge generation layer containing a charge generator on the conductive substrate 12 by means of vapor deposition or coating. Then, a coating solution containing at least one amine stilbene derivative (hole transport agent) represented by the general formula (1) and a binder resin is applied onto the charge generation layer 24 and dried. In this way, the charge transport layer 22 is formed.
In contrast to the above structure, as shown in FIG. 2B, the charge transport layer 22 may be formed on the conductive substrate 12, and the charge generation layer 24 may be formed thereon.
However, since the charge generation layer 24 is much thinner than the charge transport layer 22, for protection, the charge transport layer 22 is formed on the charge generation layer 24 as shown in FIG. It is more preferable to form
The charge generating agent, hole transporting agent, electron transporting agent, binder and the like can be the same as those of the single layer type photoreceptor.
Further, the thickness of the photosensitive layer in the multilayer photoreceptor is about 0.01 to 5 μm, preferably about 0.1 to 3 μm for the charge generation layer, and 2 to 100 μm, preferably 5 to 50 μm for the charge transport layer. Degree.

  Hereinafter, the present invention will be described in detail with reference to Examples and Comparative Examples.

[Example 1]
The synthesis example of the formylation triphenylamine derivative represented by Formula (1 ') by implementing sequentially following Reaction formula (4)-Reaction formula (8) is shown.

(1) Synthesis of triphenylamine compound First, synthesis of a triphenylamine compound represented by the following formula (10) was performed according to the following reaction formula (4).
That is, 152.0 g (1.10 mol) of anhydrous potassium carbonate and 9.5 g (0.15 mol) of anhydrous copper carbonate were added into a two-necked flask having a volume of 500 ml, heated for 2 hours, and stirred until uniform. . Next, after cooling to room temperature, 67.6 g (0.5 mol) of an aniline compound represented by the following formula (9) and 305.9 g (1.5 mol) of iodobenzene were added, and then reheated to 220 ° C. And allowed to react for 2.5 hours. Then, after cooling to room temperature, 100 ml of toluene was added and filtered. The obtained residue was dissolved in toluene and dried using activated clay. Thereafter, the residue was dissolved in toluene, and methanol was further added for crystallization. Thereafter, the residue was dissolved again with toluene, and methanol was further added to cause crystallization. The obtained crystals were separated by filtration and dried. Thereafter, the obtained crystal was purified using silica gel column chromatography (developing solvent: chloroform / hexane solvent) to obtain 79.3 g of a triphenylamine compound represented by the formula (10) (yield 55.2). %).

(2) Synthesis of formylated triphenylamine compound Next, the synthesis of the formylated triphenylamine compound represented by the formula (11) was carried out according to the following reaction formula (5).
That is, in a 500 ml flask, 60 g (0.21 mol) of the triphenylamine compound represented by the formula (10), 450 ml of dimethylformamide (DMF), 41.8 g (0.27 mol) of oxychlorophosphoric acid, And stirred at 85 ° C. or higher for 3 hours. After the reaction, the reaction solution was dropped into 600 ml of ion-exchanged water, and the precipitated solid was filtered off. The obtained solid was stirred and washed with ion exchange water. Thereafter, the solid was dissolved in toluene, and the organic layer was washed 5 times with ion-exchanged water. Thereafter, anhydrous sodium sulfate and activated clay were added to the obtained organic layer, followed by drying and adsorption treatment. Thereafter, toluene was distilled off under reduced pressure, and the residue was dissolved in 200 ml of toluene and crystallized from methanol to obtain 51.4 g of a formylated triphenylamine compound represented by the formula (11) (yield 77.6). %).

(3) Synthesis of phosphorus ylide derivative Subsequently, the phosphorus ylide derivative represented by the formula (12) was synthesized according to the following reaction formula (6).
That is, 150 g (0.61 mol) of α-bromodiphenylmethane and 121 g (0.72 mol) of triethanol phosphoric acid were added, heated at 210 ° C., and stirred for 1 hour. Then, after cooling to room temperature, purification was performed by vacuum distillation. The obtained residue was purified using silica gel column chromatography (developing solvent: ethyl acetate solvent) to obtain 168.4 g of a phosphorus ylide derivative represented by the formula (12) (yield 90.7%).

(4) Synthesis of Triphenylamine Derivative Next, a triphenylamine derivative represented by the following formula (13) was synthesized according to the following reaction formula (7).
That is, after adding 25 g (0.082 mol) of the phosphorus ylide derivative represented by the formula (12) into a 1000 ml four-necked flask, argon gas replacement was performed, and further 100 ml of THF was accommodated and reacted at 5 ° C. or lower. I let you. Thereafter, 51.2 ml of n-BuLi (1.6M in hexane solution) was added dropwise, and the mixture was stirred at 7 ° C. or lower for 30 minutes. Further, a solution of 18 g (0.057 mol) of a formylated triphenylamine compound represented by the formula (11) dissolved in 45 ml of THF was added dropwise and stirred at 6 ° C. or lower for 30 minutes. This reaction solution was added to 500 ml of ion-exchanged water and extracted with toluene. Further, the obtained organic layer was washed 5 times with ion-exchanged water, and then the organic layer was dried and adsorbed with anhydrous magnesium sulfate and activated clay. Thereafter, the organic solvent was distilled off, left at room temperature for 2 days, the precipitated solid was filtered off using petroleum ether, and the obtained solid was dried under reduced pressure. The obtained solid was purified by column chromatography (developing solvent: chloroform / hexane solvent) to obtain 21.4 g of a triphenylamine derivative represented by the formula (13) (yield: 80. 6%).

(5) Synthesis of formylated triphenylamine derivative Next, a formylated triphenylamine derivative represented by the following formula (14) was carried out according to the following reaction formula (8).
That is, in a 500 ml flask, 20 g (0.043 mol) of the triphenylamine derivative represented by the formula (13), 300 ml of dimethylformamide (DMF), 8.6 g (0.06 mol) of oxychlorophosphoric acid, And stirred at 95 ° C. for 3 hours. Thereafter, the reaction solution was poured into 500 ml of ion-exchanged water, and the precipitated crystals were separated by filtration. The obtained solid was stirred and washed twice with ion-exchanged water. Furthermore, the obtained crystal | crystallization was dissolved in toluene, and the organic layer was wash | cleaned 5 times using ion-exchange water. Furthermore, anhydrous magnesium sulfate and activated clay were added to the organic layer, and after drying and adsorption treatment, the solvent was distilled off under reduced pressure. The obtained residue was purified by silica gel column chromatography (developing solvent: chloroform solvent) to obtain 17.8 g of a formylated triphenylamine derivative represented by the formula (14) (yield 84.0%).

[Comparative Example 1]
By carrying out the following reaction formula (9), the ditriphenylamine compound represented by the following formula (15) is formylated by the Vilsmeier method to form a formylated triphenylamine derivative represented by the following formula (16). A synthesis was attempted.
However, almost no Vilsmeier reaction occurred, and it was confirmed that the yield of the amine stilbene derivative itself represented by the general formula (16) was extremely low.
That is, since the yield of the formylated triphenylamine derivative represented by the following formula (16) is low, it was found that the amine stilbene derivative represented by the following formula (17) cannot be obtained.

As described above in detail, according to the formylated triphenylamine derivative of the present invention and the production method thereof, a triphenylamine derivative having a formyl group at a predetermined position in the molecule can be obtained in high yield.
Therefore, using the formylated triphenylamine derivative as a starting material (intermediate), it has a bulky group in the molecule, is highly compatible with the binder resin, and has a high charge transport ability (hole transport ability). The resulting amine stilbene derivative can be obtained efficiently, and as a result, an electrophotographic photoreceptor can be obtained stably at low cost.

(A)-(c) is a figure provided in order to demonstrate the basic structure and deformation | transformation structure of a single layer type photoreceptor. (A)-(b) is a figure provided in order to demonstrate the basic structure and deformation | transformation structure of a laminated type photoreceptor.

Explanation of symbols

10: Single layer type photoreceptor 12: Conductive substrate 14: Photosensitive layer 16: Barrier layer 18: Protective layer 20: Multilayer type photoreceptor 22: Charge transport layer 24: Charge generation layer

Claims (6)

A formylated triphenylamine derivative represented by the following general formula (1):

(In General Formula (1), a plurality of R ^{1 to} R ¹⁰ are each independently a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted group having 1 to 20 carbon atoms, or An unsubstituted alkoxy group, a substituted or unsubstituted aryl group having 6 to 20 carbon atoms, or a substituted or unsubstituted amino group.) The formylated triphenylamine derivative according to claim 1, wherein R ^{1 to} R ¹⁰ in the general formula (1) are a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. A method for producing a formylated triphenylamine derivative represented by the following reaction formula (1), wherein the triphenylamine derivative represented by the general formula (2) is formylated by the Vilsmeier method. A method for producing a formylated triphenylamine derivative.

(In the reaction formula (1), a plurality of R ^{1 to} R ¹⁰ are each independently a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted group having 1 to 20 carbon atoms, or An unsubstituted alkoxy group, a substituted or unsubstituted aryl group having 6 to 20 carbon atoms, or a substituted or unsubstituted amino group.) As shown in the following reaction formula (2), the triphenylamine derivative represented by the general formula (2) is reacted with an aniline derivative represented by the general formula (3) and iodobenzene, After obtaining the triphenylamine derivative represented by the general formula (4) and then formylating by the Vilsmeier method, the formylated triphenylamine derivative represented by the general formula (5) and the general formula The method for producing a formylated triphenylamine derivative according to claim 3, wherein a triphenylamine derivative obtained by reacting the phosphorus ylide derivative represented by (6) with a Wittig reaction is used. .

(In the reaction formula (2), the plurality of R ^{1 to} R ¹⁰ are the same as those in the reaction formula (1).)   In the Wittig reaction, the formylation triphenylamine compound represented by the general formula (5) and the phosphorus ylide derivative represented by the general formula (6) are reacted in the presence of a catalyst. The method for producing a formylated triphenylamine derivative according to claim 4.   The method for producing a formylated triphenylamine derivative according to claim 5, wherein the catalyst used in the Wittig reaction is alkyllithium.

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