JP2008222669A - Production method of 2,4-diphenyl-4-methyl-1-pentene - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a dimerization of α-methylstyrene, namely, a method for obtaining 2,4-diphenyl-4-methyl-1-pentene with high selectivity. <P>SOLUTION: The production method of 2,4-diphenyl-4-methyl-1-pentene comprises reacting α-methylstyrene in the presence of (A) a strongly acidic ion exchange resin catalyst and (B) an additive selected from a linear polyether compound, a compound having a hydroxy group and an ether bond in a molecule, a compound having a hydroxy group and an ester bond in a molecule and a compound having an ester bond and an ether bond in a molecule. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

The present invention relates to a process for producing 2,4-diphenyl-4-methyl-1-pentene.
More specifically, α-methylstyrene is synthesized from a strongly acidic ion exchange resin catalyst, a linear polyether compound, a compound having a hydroxyl group and an ether bond in the molecule, a compound having a hydroxyl group and an ester bond in the molecule, and the molecule. The present invention relates to a process for producing 2,4-diphenyl-4-methyl-1-pentene, which is reacted in the presence of an additive selected from compounds having an ester bond and an ether bond.

  2,4-diphenyl-4-methyl-1-pentene is mainly used as a molecular weight regulator in producing SBR, ABS resin and the like by radical polymerization.

It is known that 2,4-diphenyl-4-methyl-1-pentene can be produced by dimerizing α-methylstyrene using sulfuric acid, p-toluenesulfonic acid, strongly acidic ion exchange resin or activated clay as a catalyst. Yes.
In this case, in addition to 2,4-diphenyl-4-methyl-1-pentene, 2,4-diphenyl-4-methyl-2-pentene, 1,1,3-trimethyl-3-phenylindane and several kinds of Trimers are by-produced.

  Various methods have been disclosed for increasing the selectivity of 2,4-diphenyl-4-methyl-1-pentene which is a dimerization reaction product of α-methylstyrene using an acid catalyst.

  For example, in a method for producing an unsaturated dimer of an α-alkylstyrene by reacting an α-alkylstyrene with the presence of a solid acid or a cation exchange resin catalyst, water, a dihydric alcohol or a polyhydric alcohol is added to the reaction system. A method for producing an unsaturated dimer of α-alkylstyrenes characterized in that a compound selected from the group consisting of monohydric alcohols is present (see, for example, Patent Document 1). However, when a cation exchange resin catalyst was used (Example 5), the selectivity for 2,4-diphenyl-4-methyl-1-pentene in the dimer was 72 / (72 + 10) = 87.8%. There are low drawbacks.

  The α-methylstyrenes are reacted in the presence of a clay catalyst and dihydric alcohol in a ratio in which the weight ratio of the clay catalyst to the dihydric alcohol is 0.007 to 1.0. 2,4 -A manufacturing method of diphenyl-4-methyl-1-pentene is described (for example, refer to patent documents 2).

  A sulfonic acid type cation exchange resin is used as a catalyst, and a primary or secondary monohydric alcohol having 2 to 5 carbon atoms is allowed to coexist in the reaction system, and in the temperature range of 20 to 100 ° C., α- A method for producing an unsaturated dimer of α-methylstyrenes characterized by dimerizing methylstyrenes is described (for example, see Patent Document 3). In the examples of the publication, 1,1,3-trimethyl-3-phenylindane is not produced, and the selectivity of 2,4-diphenyl-4-methyl-1-pentene is described as 95 to 97%. . However, it cannot be reproduced even in a supplementary test (Comparative Example 1 described later).

（式中、Ｒ^１は炭素数１〜６のアルキル基であり、Ｒ^２、Ｒ^３は水素又はメチル基であり、ｎは２又は３の数である）
で表される助触媒の存在下で反応させることを特徴とする方法（例えば、特許文献６参照。）の記載がある。 As a method for producing 2,4-diphenyl-4-methyl-1-pentene with high selectivity when using activated clay or acidic clay as a catalyst, aliphatic monoether, aliphatic hybrid ether, and cyclic ether are used. A method characterized by reacting in the presence of one or more selected organic compounds (for example, see Patent Document 4), a method characterized by coexisting cellosolve (for example, see Patent Document 5), etc. formula

(Wherein R ¹ is an alkyl group having 1 to 6 carbon atoms, R ² and R ³ are hydrogen or a methyl group, and n is a number of 2 or 3)
There exists description of the method (for example, refer patent document 6) characterized by making it react in presence of the cocatalyst represented by these.

  Further, the method is characterized in that a substance having a lone electron pair in the molecule is added as a reaction-controlling compound in the presence of an acid catalyst, wherein the substance having a lone electron pair in the molecule is a carboxylic acid or its There is described a method for producing an unsaturated dimer, which is one of anhydrides, sulfonic acids, thiophenes, nitriles, cyclic esters, or a combination of two or more (for example, Patent Document 7). reference.). However, the selectivity of 2,4-diphenyl-4-methyl-1-pentene in the dimer is not mentioned.

Japanese Patent Publication No.49-32845 JP-A-5-70378 Japanese Patent Publication No.52-31866 JP-A-57-62228 JP 59-190927 A JP-A-63-192727 JP 59-204139 A

2,4-diphenyl-4-methyl-1-pentene is mainly used as a molecular weight regulator for radical polymerization. 2,4-Diphenyl-4-methyl-2-pentene by-produced in the production of 2,4-diphenyl-4-methyl-1-pentene which is a dimer of α-methylstyrene in the presence of an acid catalyst 1,1,3-trimethyl-3-phenylindane and some trimers are 2,4-diphenyl-4-methyl-2-pentene and 1,1,3-trimethyl-3-phenylindane. Since the boiling point is close to 2,4-diphenyl-4-methyl-1-pentene, it is difficult to extract 2,4-diphenyl-4-methyl-1-pentene from the reaction solution with a high recovery rate.
2,4-diphenyl-4-methyl-2-pentene has a weak molecular weight adjusting action in radical polymerization reaction, and 1,1,3-trimethyl-3-phenylindane has no action at all. These are not involved in the radical polymerization reaction and remain in the polymer as unreacted substances, which adversely affects the physical properties of the polymer.
Therefore, it is important to find a dimerization reaction condition in which 2,4-diphenyl-4-methyl-2-pentene and 1,1,3-trimethyl-3-phenylindane are reduced as much as possible.
However, it cannot be said that the selectivity of 2,4-diphenyl-4-methyl-1-pentene in the dimer is sufficiently high in the prior art.

  As a result of intensive studies, the present inventors have determined that α-methylstyrene is a strongly acidic ion exchange resin catalyst, a linear polyether compound, a compound having a hydroxyl group and an ether bond in the molecule, and a hydroxyl group and an ester bond in the molecule. And 2,4-diphenyl-4-methyl-1-pentene can be obtained with high selectivity by reacting in the presence of an additive selected from compounds having an ester bond and an ether bond in the molecule. The present invention has been found.

  That is, the present invention relates to α-methylstyrene, (A) a strongly acidic ion exchange resin catalyst, (B) a linear polyether compound, a compound having a hydroxyl group and an ether bond in the molecule, and a hydroxyl group in the molecule. Production of 2,4-diphenyl-4-methyl-1-pentene characterized by reacting in the presence of a compound having an ester bond and an additive selected from compounds having an ester bond and an ether bond in the molecule Regarding the law.

  The present invention also relates to the above process wherein the linear polyether compound is a compound selected from the group consisting of diethylene glycol dimethyl ether, 1,2-dimethoxyethane and 1,2-diethoxyethane.

  In the present invention, the compound having a hydroxyl group and an ether bond in the molecule is composed of 1-methoxy-2-propanol, 1-ethoxy-2-propanol, 3-methoxy-1-butanol and tetrahydrofurfuryl alcohol. It relates to the above process, characterized in that it is a selected compound.

  The present invention also relates to the above method, wherein the compound having a hydroxyl group and an ester bond in the molecule is a compound selected from the group consisting of methyl lactate and ethyl lactate.

  In the present invention, the compound having an ester bond and an ether bond in the molecule is 1-acetoxy-2-ethoxyethane, 1-acetoxy-2-methoxyethane, 2-acetoxy-1-methoxypropane, 2-acetoxy-1 -It relates to the above process, characterized in that it is a compound selected from the group consisting of ethoxypropane, 1-acetoxy-3-methoxybutane and 2- (2-ethoxyethoxy) ethyl acetate.

  According to the present invention, 2,4-diphenyl-4-methyl-1-pentene can be produced from α-methylstyrene with high selectivity.

  The products of the α-methylstyrene dimerization reaction are 2,4-diphenyl-4-methyl-1-pentene, 2,4-diphenyl-4-methyl-2-pentene and 1,1,3-trimethyl-3- There are three types of phenylindane. Several other trimers are produced. The present invention is a method for producing 2,4-diphenyl-4-methyl-1-pentene among them with high selectivity.

  The catalyst used in the present invention is not particularly limited as long as it is a strongly acidic ion exchange resin, and examples thereof include sulfonic acid type strongly acidic ion exchange resins. The sulfonic acid type strongly acidic ion exchange resin may be a strong acid ion exchange resin having a sulfonic acid group. For example, a sulfonated styrene-divinylbenzene copolymer in which a sulfonic acid group is introduced into a styrene-divinylbenzene copolymer. Examples thereof include a polymer, a sulfonated crosslinked styrene polymer obtained by introducing a sulfonic acid group into a crosslinked styrene polymer, a phenol formaldehyde-sulfonic acid resin, and a benzeneformaldehyde-sulfonic acid resin. The strongly acidic ion exchange resin may be a gel type or a porous type. Specific examples of the sulfonic acid type strongly acidic ion exchange resin catalyst include, for example, Amberlyst IR-15 (trade name, manufactured by Organo Corporation), Dow Extract 50WX (trade name, manufactured by Dow Chemical Company), and the like. It is not limited to these.

  In the present invention, (A) a strongly acidic ion exchange resin catalyst, (B) a linear polyether compound, a compound having a hydroxyl group and an ether bond in the molecule, a compound having a hydroxyl group and an ester bond in the molecule, and Α-methyl in the presence of an additive selected from compounds having an ester bond and an ether bond in the molecule (hereinafter, the additive in (B) may be simply referred to as additive (B)). React with styrene. As the additive (B), the above-mentioned various compounds may be used alone or in combination of two or more.

（式中、Ｒ⁴及びＲ⁶は、各々独立に、炭素数１〜４の直鎖又は分岐アルキル基、好ましくは炭素数１〜２の直鎖アルキル基を表し、Ｒ⁵は、メチレン基、炭素数２〜４、好ましくは２〜３の直鎖若しくは分岐アルキレン基又は炭素数２〜６、好ましくは２〜４の直鎖若しくは分岐アルキリデン基を表し、ｘは１〜４、好ましくは１〜２の整数を表す。）
で表される化合物が挙げられる。Ｒ⁵の具体例としては、例えば、メチレン基、エチレン基、トリメチレン基、プロピレン基、１−メチルトリメチレン基、２−メチルトリメチレン基、エチリデン基、イソプロピリデン基、イソブチリデン基等が挙げられる。また、線状ポリエーテル化合物の具体例としては、ジエチレングリコールジメチルエーテル、１，２−ジメトキシエタン、１，２−ジエトキシエタン等が挙げられる。 Among the additives (B), as the linear polyether compound, for example, the following general formula (1)

(Wherein R ⁴ and R ⁶ each independently represents a linear or branched alkyl group having 1 to 4 carbon atoms, preferably a linear alkyl group having 1 to 2 carbon atoms, and R ⁵ represents a methylene group, A linear or branched alkylene group having 2 to 4 carbon atoms, preferably 2 to 3 carbon atoms, or a linear or branched alkylidene group having 2 to 6 carbon atoms, preferably 2 to 4 carbon atoms, and x is 1 to 4, preferably 1 to 4. Represents an integer of 2.)
The compound represented by these is mentioned. Specific examples of R ⁵ include methylene group, ethylene group, trimethylene group, propylene group, 1-methyltrimethylene group, 2-methyltrimethylene group, ethylidene group, isopropylidene group, and isobutylidene group. Specific examples of the linear polyether compound include diethylene glycol dimethyl ether, 1,2-dimethoxyethane, 1,2-diethoxyethane and the like.

（式中、Ｒ⁷は炭素数１〜４、好ましくは１〜３の直鎖又は分岐アルキル基を表し、Ｒ⁸は炭素数２〜６、好ましくは２〜４の直鎖若しくは分岐アルキレン基を表し、ｙは１〜３、好ましくは１〜２の整数を表す。）
及び下記式（３） Among the additives (B), examples of the compound having a hydroxyl group and an ether bond in the molecule include the following general formula (2):

(Wherein R ⁷ represents a linear or branched alkyl group having 1 to 4 carbon atoms, preferably 1 to 3 carbon atoms, and R ⁸ represents a linear or branched alkylene group having 2 to 6 carbon atoms, preferably 2 to 4 carbon atoms. And y represents an integer of 1 to 3, preferably 1 or 2).
And the following formula (3)

で表される化合物が挙げられる。一般式（２）において、Ｒ⁸が表すアルキレン基は、特に分岐アルキレン基であることが好ましく、例えば、プロピレン基、１−メチルトリメチレン基等が好ましい。また、一般式（２）において、ｙは１であることが特に好ましい。分子内にヒドロキシル基とエーテル結合を有する化合物の具体例としては、例えば、１−メトキシ−２−プロパノール、１−エトキシ−２−プロパノール、テトラヒドロフルフリルアルコール、３−メトキシ−１−ブタノール等が挙げられる。

The compound represented by these is mentioned. In the general formula (2), the alkylene group represented by R ⁸ is particularly preferably a branched alkylene group, and for example, a propylene group, a 1-methyltrimethylene group, and the like are preferable. In general formula (2), y is particularly preferably 1. Specific examples of the compound having a hydroxyl group and an ether bond in the molecule include 1-methoxy-2-propanol, 1-ethoxy-2-propanol, tetrahydrofurfuryl alcohol, 3-methoxy-1-butanol and the like. It is done.

（式中、Ｒ⁹は、メチレン基、炭素数２〜１０、好ましくは２〜３の直鎖若しくは分岐アルキレン基又は炭素数２〜１０、好ましくは２〜３の直鎖若しくは分岐アルキリデン基を表し、Ｒ¹⁰は、炭素数１〜４、好ましくは１〜２の直鎖又は分岐アルキル基を表す。）
で表される化合物が挙げられる。Ｒ⁹の具体例としては、メチレン基、エチリデン基、プロピリデン基等が挙げられる。分子内にヒドロキシル基とエステル結合を有する化合物の具体例としては、例えば、乳酸メチル、乳酸エチル等が挙げられる。 Among the additives (B), examples of the compound having a hydroxyl group and an ester bond in the molecule include the following general formula (4).

(In the formula, R ⁹ represents a methylene group, a linear or branched alkylene group having 2 to 10 carbon atoms, preferably 2 to 3 carbon atoms, or a linear or branched alkylidene group having 2 to 10 carbon atoms, preferably 2 to 3 carbon atoms. , R ¹⁰ represents a linear or branched alkyl group having 1 to 4 carbon atoms, preferably 1 to 2 carbon atoms.)
The compound represented by these is mentioned. Specific examples of R ⁹ include a methylene group, an ethylidene group, and a propylidene group. Specific examples of the compound having a hydroxyl group and an ester bond in the molecule include methyl lactate and ethyl lactate.

（式中、Ｒ¹¹及びＲ¹³は、各々独立に、炭素数１〜４、好ましくは１〜２の直鎖アルキル基を表し、Ｒ¹²は、炭素数２〜４、好ましくは２〜３の直鎖若しくは分岐アルキレン基を表し、ｚは、１〜３、好ましくは１の整数を表す。）
で表される化合物が挙げられる。Ｒ¹²の具体例としては、例えば、エチレン基、プロピレン基、１−メチルトリメチレン基等が挙げられる。分子内にエステル結合とエーテル結合を有する化合物の具体例としては、例えば、１−アセトキシ−２−メトキシエタン、１−アセトキシ−２−エトキシエタン、２−アセトキシ−１−メトキシプロパン、２−アセトキシ−１−エトキシプロパン、１−アセトキシ−３−メトキシブタン、酢酸２−（２−エトキシエトキシ）エチル等が挙げられる。 Among the additives (B), examples of the compound having an ester bond and an ether bond in the molecule include the following general formula (5).

(In the formula, R ¹¹ and R ¹³ each independently represents a linear alkyl group having 1 to 4 carbon atoms, preferably 1 to 2 carbon atoms, and R ¹² has 2 to 4 carbon atoms, preferably 2 to 3 carbon atoms. Represents a linear or branched alkylene group, and z represents an integer of 1 to 3, preferably 1.
The compound represented by these is mentioned. Specific examples of R ¹² include an ethylene group, a propylene group, a 1-methyltrimethylene group, and the like. Specific examples of the compound having an ester bond and an ether bond in the molecule include 1-acetoxy-2-methoxyethane, 1-acetoxy-2-ethoxyethane, 2-acetoxy-1-methoxypropane, 2-acetoxy- Examples include 1-ethoxypropane, 1-acetoxy-3-methoxybutane, and 2- (2-ethoxyethoxy) ethyl acetate.

  Moreover, you may coexist other additives, for example, a small amount of water, in addition to the said additive (B) as needed.

  The amount of the strongly acidic ion exchange resin catalyst (A) used is preferably 0.2 to 10 parts by weight, more preferably 0.5 to 5 parts by weight, based on 100 parts by weight of α-methylstyrene. . If the amount of the strongly acidic ion exchange resin catalyst (A) used is less than 0.2 parts by weight, the dimerization reaction tends to be insufficient, and if it exceeds 10 parts by weight, the reaction becomes too fast. The reaction temperature tends to be difficult to control.

  The amount of additive (B) used is preferably 0.1 to 100 parts by weight, more preferably 0.2 to 50 parts by weight, and still more preferably 0.5 to 100 parts by weight of α-methylstyrene. It is preferable to set it as -20 weight part. When the amount of additive (B) used is less than 0.1 parts by weight, the effect as additive (B), that is, the effect of improving the selectivity of 2,4-diphenyl-4-methyl-1-pentene is obtained. When it exceeds 100 parts by weight, the reaction rate tends to become extremely slow.

  The reaction is preferably performed at 0 to 100 ° C, more preferably 20 to 80 ° C. It is preferable to adjust the temperature so that the conversion of α-methylstyrene reaches 80% in 3 to 8 hours after the start of the reaction.

  Generally, at the initial stage of α-methylstyrene dimerization reaction (conversion rate <50%), the selectivity for 2,4-diphenyl-4-methyl-1-pentene in the dimer is high. If the reaction solution is distilled, 2,4-diphenyl-4-methyl-1-pentene in the dimer can be extracted with a high recovery rate. However, since the number of reaction operations and distillation operations required for obtaining 2,4-diphenyl-4-methyl-1-pentene per unit increases, the cost increases.

On the other hand, when the conversion rate of the α-methylstyrene dimerization reaction exceeds about 50%, the isomerization from 2,4-diphenyl-4-methyl-1-pentene to 2,4-diphenyl-4-methyl-2-pentene occurs. Therefore, the selectivity of 2,4-diphenyl-4-methyl-1-pentene in the dimer gradually decreases, and particularly when the conversion exceeds about 80%, the selectivity decreases rapidly.
Therefore, it is preferable to stop the reaction when the conversion rate reaches about 80%, and distill the reaction solution to recover 2,4-diphenyl-4-methyl-1-pentene.

According to the method of the present invention, when the reaction proceeds about 80% (unreacted α-methylstyrene is about 20%), 92 to 94% of the dimer produced is usually 2,4-diphenyl- 4-methyl-1-pentene.
After the reaction, the catalyst-removed (filtered) liquid can be applied to a precision distillation apparatus to obtain high-purity 2,4-diphenyl-4-methyl-1-pentene. The recovered catalyst, unreacted α-methylstyrene, and additives can be reused.

  Hereinafter, the present invention will be described more specifically with reference to examples of the present invention and comparative examples thereof, but the present invention is not limited to these examples.

[Example 1]
After putting 1.00 g of Amberlyst IR-15 (manufactured by Organo Corporation, sulfonic acid type cation exchange resin, anhydrous) and 5 ml (4.7 g) of diethylene glycol dimethyl ether into a 200 ml three-necked flask, and thoroughly blending the resin with diethylene glycol dimethyl ether , 50.0 g of α-methylstyrene was added and reacted at 41 ° C. for 6 hours. The composition of the reaction solution was analyzed using a gas chromatograph, the amount of unreacted α-methylstyrene and the amount of each reaction product were determined, and the ratio (100 fraction) to the α-methylstyrene amount of the raw material was calculated.
The results are shown in Table 1.

[Example 2]
In the same manner as in Example 1 except that 5 ml (4.4 g) of 1,2-dimethoxyethane was used instead of diethylene glycol dimethyl ether, the reaction temperature was changed to 30 ° C., and the reaction time was changed to 4 hours. The composition analysis of was performed. The results are shown in Table 1.

[Example 3]
The reaction was conducted in the same manner as in Example 1 except that 5 ml (4.6 g) of 1-methoxy-2-propanol was used instead of diethylene glycol dimethyl ether, the reaction temperature was changed to 55 ° C., and the reaction time was changed to 6.5 hours. The composition of the reaction solution was analyzed. The results are shown in Table 1.

[Example 4]
Composition analysis of reaction and reaction solution in the same manner as in Example 1 except that 2 ml (2.1 g) of tetrahydrofurfuryl alcohol was used instead of diethylene glycol dimethyl ether, the reaction temperature was changed to 48 ° C., and the reaction time was changed to 7 hours. Was done. The results are shown in Table 1.

[Example 5]
In the same manner as in Example 1 except that 5 ml (5.2 g) of ethyl lactate was used instead of diethylene glycol dimethyl ether, the reaction temperature was changed to 25 ° C., and the reaction time was changed to 4 hours, the composition analysis of the reaction and the reaction solution was performed. I did it. The results are shown in Table 1.

[Example 6]
In the same manner as in Example 1 except that 20 ml (19.4 g) of 1-acetoxy-2-ethoxyethane was used instead of diethylene glycol dimethyl ether, the reaction temperature was changed to 25 ° C., and the reaction time was changed to 6.5 hours. The composition of the reaction and the reaction solution was analyzed. The results are shown in Table 1.

Comparative Example 1
According to the example of JP-B-52-31866, Amberlyst IR-15 (manufactured by Organo Corporation, sulfonic acid type cation exchange resin, anhydrous) was added to a mixed solution of 50.0 g α-methylstyrene and 1.0 g n-butanol 1.00 g was added and reacted at 60 ° C. for 1 hour. The composition of the reaction solution was analyzed in the same manner as in Example 1. The results are shown in Table 1.

[Comparative Example 2]
The same procedure as in Example 1 was conducted except that 5 ml (5.2 g) of dioxane described in JP-A-57-62228 was used instead of diethylene glycol dimethyl ether, the reaction temperature was changed to 48 ° C., and the reaction time was changed to 2 hours. The composition of the reaction and the reaction solution was analyzed. The results are shown in Table 1.

[Comparative Example 3]
The same procedure as in Example 1 was conducted except that 1 ml (1.12 g) of diethylene glycol described in JP-B-49-32845 was used instead of diethylene glycol dimethyl ether, the reaction temperature was changed to 95 ° C., and the reaction time was changed to 6.5 hours. Then, the composition of the reaction and the reaction solution was analyzed. The results are shown in Table 1.

AMS represents α-methylstyrene.
P-1 represents 2,4-diphenyl-4-methyl-1-pentene.
P-2 represents 2,4-diphenyl-4-methyl-2-pentene.
IN represents 1,1,3-trimethyl-3-phenylindane.
P-1 selectivity represents the ratio of P-1 (2,4-diphenyl-4-methyl-1-pentene) in the dimer (P-1, P-2, IN).

  From Table 1, compared with the primary alcohol n-butanol used in Comparative Examples 1 to 3, the diether of cyclic ether and diethylene glycol which is a dihydric alcohol, the linear poly of the additive (B) of the present invention. Diethylene glycol dimethyl ether as ether and 1,2-dimethoxyethane, 1-methoxy-2-propanol and tetrahydrofurfuryl alcohol as compounds having a hydroxyl group and an ether bond in the molecule, compounds having a hydroxyl group and an ester bond in the molecule 2,4-diphenyl-4-methyl-1-pentene (P-1) is obtained by using ethyl lactate, and 1-acetoxy-2-ethoxyethane, which is a compound having an ester bond and an ether bond in the molecule. It is clear that the selectivity of) is high.

Claims (5)

  α-methylstyrene, (A) a strongly acidic ion exchange resin catalyst, (B) a linear polyether compound, a compound having a hydroxyl group and an ether bond in the molecule, a compound having a hydroxyl group and an ester bond in the molecule, and A process for producing 2,4-diphenyl-4-methyl-1-pentene, which comprises reacting in the presence of an additive selected from compounds having an ester bond and an ether bond in the molecule.   The method according to claim 1, wherein the linear polyether compound is a compound selected from the group consisting of diethylene glycol dimethyl ether, 1,2-dimethoxyethane, and 1,2-diethoxyethane.   The compound having a hydroxyl group and an ether bond in the molecule is a compound selected from the group consisting of 1-methoxy-2-propanol, 1-ethoxy-2-propanol, 3-methoxy-1-butanol and tetrahydrofurfuryl alcohol. The method of claim 1, wherein:   The method according to claim 1, wherein the compound having a hydroxyl group and an ester bond in the molecule is a compound selected from the group consisting of methyl lactate and ethyl lactate.   Compounds having an ester bond and an ether bond in the molecule are 1-acetoxy-2-ethoxyethane, 1-acetoxy-2-methoxyethane, 2-acetoxy-1-methoxypropane, 2-acetoxy-1-ethoxypropane, 2. The method according to claim 1, wherein the compound is selected from the group consisting of acetoxy-3-methoxybutane and 2- (2-ethoxyethoxy) ethyl acetate.