KR20210131633A - Method for preparing deuterated aromatic compounds - Google Patents

Abstract

The present invention relates to a method for preparing a deuterated aromatic compound comprising: a step for preparing a solution including a deuterium source, a metal catalyst, a neutral metal salt, and an aromatic compound having at least one aromatic ring in a reactor; and a step for heating the reactor so as to allow a deuterated reaction of the aromatic compound to proceed.

Description

The manufacturing method of a deuterated aromatic compound TECHNICAL FIELD

The present specification relates to a method for preparing a deuterated aromatic compound.

Compounds containing deuterium are used for various purposes. For example, compounds containing deuterium are widely used not only as labeling compounds for identification of chemical reaction mechanisms or metabolism, but also for drugs, pesticides, organic EL materials, and other purposes.

A method of substituting deuterium for an aromatic compound to improve the lifespan of an organic light emitting diode (OLED) material is known. The principle of this effect is that the LUMO energy of the C-D bond is lower than that of the C-H bond when deuterium is substituted, and the lifespan characteristics of the OLED material are improved.

When the deuterated reaction proceeds with respect to one or more aromatic compounds using the conventional heterogeneous catalyst reaction, there is a problem in that by-products due to side reactions are continuously generated. This is due to the hydrogenation reaction generated by hydrogen gas, and an attempt was made to increase the purity through the purification process after the reaction to remove it, but it was difficult to have high purity because there was no difference from the existing material in terms of melting point or solubility. In order to improve this, in order to react without hydrogen gas, the reaction must be carried out at a very high temperature (about 220° C. or higher), which may cause a problem in stability in the process.

The present specification provides a method for preparing a deuterated aromatic compound.

The present specification includes the steps of preparing a solution containing a deuterium source, a metal catalyst, an aromatic compound including a metal salt having neutral acidity and one or more aromatic rings; and heating the solution to advance the deuterated reaction of the aromatic compound.

The manufacturing method of the first embodiment according to the present specification can suppress the generation of impurities.

The manufacturing method of the second embodiment according to the present specification has an advantage of high deuterium substitution rate.

The manufacturing method of the third embodiment according to the present specification has the advantage of high purity of the obtained compound.

In the manufacturing method of the fourth embodiment according to the present specification, the reaction is possible at a lower pressure.

Hereinafter, the present specification will be described in detail.

The present specification includes the steps of preparing a solution containing a deuterium source, a metal catalyst, an aromatic compound including a metal salt having neutral acidity and one or more aromatic rings; and heating the solution to advance the deuterated reaction of the aromatic compound.

The method for producing a deuterated aromatic compound of the present specification is characterized in that there is no hydrogen supply step.

Conventionally, hydrogen gas was supplied to activate a metal catalyst, which is a heterogeneous catalyst added to prepare deuterated aromatic compounds. When hydrogen is supplied to advance the deuterium reaction, the hydrogenation reaction proceeds with hydrogen gas, thereby generating by-products due to side reactions.

In order to remove the generated by-products, it is necessary to increase the purity through the purification process after the reaction. It was difficult.

In order to improve this, in order to proceed with the deuterium reaction without hydrogen gas, the reaction must be carried out at a very high temperature (about 220° C. or higher). If the reaction temperature is raised, the internal pressure during the reaction greatly increases, causing stability problems such as explosion of the reactor. can occur In addition, it is difficult to select a reactor that can withstand high pressure, and the cost of related equipment and facilities increases.

In the method for producing a deuterated aromatic compound of the present specification, a metal salt having a neutral acidity is added to the reactant, and the metal salt lowers the reaction pressure even if the deuterated reaction proceeds at a high temperature without hydrogen gas, thereby solving the problem of stability.

The step of preparing a solution containing the deuterium source, the metal catalyst, the metal salt having neutral acidity and the aromatic compound including one or more aromatic rings is a deuterium source, the metal catalyst, and the acidity is neutral in the reactor. A solution containing a metal salt and an aromatic compound containing at least one aromatic ring is introduced, or a deuterium source, a metal catalyst, a metal salt having neutral acidity and an aromatic compound containing at least one aromatic ring are individually added to the reactor. The solution can be prepared by adding it.

The solution may further include an organic solvent. The organic solvent is not particularly limited as long as it can dissolve the aromatic compound, and may be selected according to the aromatic compound used.

When using heavy water (D ₂ O) as the deuterium source, it is preferable to select a solvent that does not have a high affinity for the organic solvent, that is, does not mix with heavy water.

When a deuterated aromatic solvent such as toluene-d8 is used as the deuterium source, an additional organic solvent may not be added.

The method for producing a deuterated aromatic compound of the present specification may further include replacing the internal air of the reactor with nitrogen or an inert gas.

According to an exemplary embodiment according to the present specification, the metal salt having a neutral acidity may be a metal salt having a pH of about 7, specifically, a metal salt having a pH of 6 to 8, and more specifically, a metal salt having a pH of 6.5 to 7.5. have.

According to an exemplary embodiment according to the present specification, the metal salt having a neutral acidity may be a metal salt formed by a neutralization reaction of a strong acid and a strong base. Specifically, the metal salt having a neutral acidity may be a metal salt containing a cation derived from a strong base and an anion derived from a strong acid, and having a neutral acidity and neutral acidity.

In addition, a metal salt formed of a strong acid and a strong base has good hygroscopicity and can be dissolved in a very large amount in water, which is advantageous in lowering the reaction pressure.

For example, at a reaction temperature of 250° C., a pressure of about 40 bar is applied to initiate the reaction without a neutral metal salt, but when a neutral metal salt is added under the same conditions, the reaction pressure can be lowered to about 3 bar.

Therefore, the reaction pressure specification can be lowered due to the neutral metal salt, which reduces equipment and process costs.

Conversely, when the acidity of the metal salt is acidic or basic, a reaction with the metal of the heterogeneous catalyst may occur to cause corrosion of the reactor of the compound to be deuterated.

According to an exemplary embodiment according to the present specification, the cation of the metal salt having a neutral acidity may be selected from lithium ion, sodium ion, potassium ion, rubidium ion, cesium ion, calcium ion, strontium ion and barium ion.

According to an exemplary embodiment according to the present specification, the anion of the metal salt having a neutral acidity may be selected from chlorine ion, iodine ion, bromine ion, SO ₄ ^2- and CF ₃ SO ₃ ⁻ .

According to an exemplary embodiment according to the present specification, based on the total weight of the solvent, the content of the metal salt having a neutral acidity may be 10 wt% or more and 150 wt% or less.

According to an exemplary embodiment according to the present specification, the metal catalyst may be a catalyst activated by contact with hydrogen gas or deuterium gas, or a non-activated catalyst.

The method for producing a deuterated aromatic compound of the present specification may further include activating the metal catalyst by contacting it with hydrogen gas or deuterium gas before the step of preparing the solution.

The metal catalyst may be, for example, activated or unactivated palladium catalyst, activated or unactivated platinum catalyst, activated or unactivated iridium catalyst, activated or unactivated rhodium catalyst, activated or unactivated unactivated ruthenium catalyst, activated or unactivated nickel catalyst and activated or unactivated cobalt catalyst. The metal catalyst may be supported on a carbon-based support.

In an exemplary embodiment of the present specification, the metal catalyst may be a metal catalyst supported on a carbon-based support. Preferably, the metal catalyst may be platinum (Pt/C) supported on a carbon-based support or palladium (Pd/C) supported on a carbon-based support.

According to an exemplary embodiment according to the present specification, based on the total weight of the aromatic compound, the content of the metal catalyst may be 0.5 wt% or more and 50 wt% or less.

The deuterium source may be a deuterium solvent, for example, heavy water (D ₂ O), benzene-d6 (Benzene-d6), toluene-d8 (Toluene-d8), etc., preferably heavy water (D ₂ O) or Toluene-d8.

According to an exemplary embodiment according to the present specification, the content of the deuterium source may be 2 times or more and 30 times or less of the aromatic compound.

In an exemplary embodiment of the present specification, the aromatic compound is an aromatic compound including one or more aromatic rings, and specifically, an aromatic compound including one or more and 30 or less aromatic rings. In this case, the number of one or more aromatic rings may include one or more monocyclic, polycyclic, or a combination thereof, or one or more aromatic rings (eg, benzene rings) as a basic unit. For example, the anthracene ring may mean one aromatic ring or three benzene rings connected based on a benzene ring as a basic unit.

According to an exemplary embodiment according to the present specification, based on the total weight of the solvent, the content of the aromatic compound may be 3 wt% or more and 50 wt% or less.

In one embodiment of the present specification, the aromatic ring may be a substituted or unsubstituted, monocyclic or polycyclic hydrocarbon aromatic ring, or a substituted or unsubstituted and monocyclic or polycyclic heteroaromatic ring. For example, the aromatic ring may be a substituted or unsubstituted benzene ring, a substituted or unsubstituted naphthalene ring, a substituted or unsubstituted anthracene ring, a substituted or unsubstituted dibenzofuran, or a substituted or unsubstituted dibenzothiophene. , and may be a substituted or unsubstituted carbazole.

In the exemplary embodiment of the present specification, the aromatic compound may be a carbazole-based compound or an anthracene-based compound.

In an exemplary embodiment of the present specification, the aromatic compound may be a carbazole-based compound, specifically substituted or unsubstituted carbazole; or a substituted or unsubstituted carbazole having an additional ring to which adjacent groups are attached.

The carbazole having an additional ring to which the adjacent groups are bonded is substituted or unsubstituted benzocarbazole; substituted or unsubstituted dibenzocarbazole; substituted or unsubstituted furocarbazole; Or it may be a substituted or unsubstituted indolocarbazole.

In one embodiment of the present specification, the aromatic compound is benzene; toluene; naphthalene; naphthylamine; indole; carbazole; anthraquinone; or dihydroindolocarbazole.

In the exemplary embodiment of the present specification, the aromatic compound may be an anthracene-based compound, and specifically may be a substituted or unsubstituted anthracene.

In an exemplary embodiment of the present specification, the aromatic compound may include a compound of Formula 1 below.

[Formula 1]

In Formula 1,

L21 to L23 are the same as or different from each other, and are each independently a direct bond; Or a substituted or unsubstituted arylene group; Or a substituted or unsubstituted heteroarylene group,

R21 to R27 are the same as or different from each other, and each independently hydrogen; a substituted or unsubstituted alkyl group; a substituted or unsubstituted cycloalkyl group; a substituted or unsubstituted silyl group; a substituted or unsubstituted aryl group; Or a substituted or unsubstituted heteroaryl group,

Ar21 to Ar23 are the same as or different from each other, and each independently a substituted or unsubstituted aryl group; Or a substituted or unsubstituted heteroaryl group,

a is 0 or 1.

Examples of substituents in the present specification are described below, but are not limited thereto.

The term “substituted” means that a hydrogen atom bonded to a carbon atom of a compound is replaced with another substituent, and the position to be substituted is not limited as long as the position at which the hydrogen atom is substituted, that is, a position where the substituent is substitutable, is not limited, and when two or more are substituted , two or more substituents may be the same as or different from each other.

As used herein, the term “substituted or unsubstituted” refers to a halogen group; nitrile group; nitro group; hydroxyl group; amine group; silyl group; boron group; alkoxy group; an alkyl group; cycloalkyl group; aryl group; And it means that it is substituted with one or two or more substituents selected from the group consisting of a heterocyclic group, is substituted with a substituent to which two or more of the above-exemplified substituents are connected, or does not have any substituents. For example, “a substituent in which two or more substituents are connected” may be a biphenyl group. That is, the biphenyl group may be an aryl group or may be interpreted as a substituent in which two phenyl groups are connected.

In the present specification, examples of the halogen group include fluorine (-F), chlorine (-Cl), bromine (-Br), or iodine (-I).

In the present specification, the silyl group may be represented by the formula of _{-SiY a} Y _b Y _{c , wherein Y a} , Y _b and Y _c are each hydrogen; a substituted or unsubstituted alkyl group; Or it may be a substituted or unsubstituted aryl group. The silyl group specifically includes, but is not limited to, a trimethylsilyl group, a triethylsilyl group, a tert-butyldimethylsilyl group, a vinyldimethylsilyl group, a propyldimethylsilyl group, a triphenylsilyl group, a diphenylsilyl group, a phenylsilyl group, and the like. does not

In the present specification, the boron group may be represented by the formula of _{-BY d} Y _{e , wherein Y d} and Y _e are each hydrogen; a substituted or unsubstituted alkyl group; Or it may be a substituted or unsubstituted aryl group. Specifically, the boron group includes, but is not limited to, a trimethylboron group, a triethylboron group, a tert-butyldimethylboron group, a triphenylboron group, a phenylboron group, and the like.

In the present specification, the alkyl group may be linear or branched, and the number of carbon atoms is not particularly limited, but is preferably 1 to 60. According to an exemplary embodiment, the number of carbon atoms in the alkyl group is 1 to 30. According to another exemplary embodiment, the alkyl group has 1 to 20 carbon atoms. According to another exemplary embodiment, the alkyl group has 1 to 10 carbon atoms. Specific examples of the alkyl group include methyl group, ethyl group, propyl group, n-propyl group, isopropyl group, butyl group, n-butyl group, isobutyl group, tert-butyl group, pentyl group, n-pentyl group, hexyl group, n -hexyl group, heptyl group, n-heptyl group, octyl group, n-octyl group, etc., but are not limited thereto.

In the present specification, the alkoxy group may be a straight chain, branched chain or cyclic chain. Although carbon number of an alkoxy group is not specifically limited, It is preferable that it is C1-C20. Specifically, methoxy, ethoxy, n-propoxy, isopropoxy, i-propyloxy, n-butoxy, isobutoxy, tert-butoxy, sec-butoxy, n-pentyloxy, neopentyloxy, isopentyloxy, n-hexyloxy, 3,3-dimethylbutyloxy, 2-ethylbutyloxy, n-octyloxy, n-nonyloxy, n-decyloxy, and the like, but is not limited thereto. .

The substituents containing an alkyl group, an alkoxy group and other alkyl group moieties described herein include both straight-chain or pulverized forms.

In the present specification, the cycloalkyl group is not particularly limited, but preferably has 3 to 60 carbon atoms, and according to an exemplary embodiment, the cycloalkyl group has 3 to 30 carbon atoms. According to another exemplary embodiment, the carbon number of the cycloalkyl group is 3 to 20. According to another exemplary embodiment, the cycloalkyl group has 3 to 6 carbon atoms. Specifically, there are a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, and the like, but is not limited thereto.

In the present specification, the aryl group is not particularly limited, but preferably has 6 to 60 carbon atoms, and may be a monocyclic aryl group or a polycyclic aryl group. According to an exemplary embodiment, the carbon number of the aryl group is 6 to 39. According to an exemplary embodiment, the carbon number of the aryl group is 6 to 30. The aryl group may be a monocyclic aryl group such as a phenyl group, a biphenyl group, a terphenyl group, or a quaterphenyl group, but is not limited thereto. The polycyclic aryl group may be a naphthyl group, anthracenyl group, phenanthrenyl group, pyrenyl group, perylenyl group, triphenyl group, chrysenyl group, fluorenyl group, triphenylenyl group, etc., but is not limited thereto no.

In the present specification, the fluorene group may be substituted, and two substituents may be bonded to each other to form a spiro structure.

,

등의 스피로플루오렌기,

(9,9-디메틸플루오렌기), 및

(9,9-디페닐플루오렌기) 등의 치환된 플루오렌기가 될 수 있다. 다만, 이에 한정되는 것은 아니다.When the fluorene group is substituted,

,

spirofluorene groups such as

(9,9-dimethylfluorene group), and

It may be a substituted fluorene group such as (9,9-diphenylfluorene group). However, the present invention is not limited thereto.

In the present specification, the heterocyclic group is a cyclic group including at least one of N, O, P, S, Si and Se as a heteroatom, and the number of carbon atoms is not particularly limited, but it is preferably from 2 to 60 carbon atoms. According to an exemplary embodiment, the heterocyclic group has 2 to 36 carbon atoms. Examples of the heterocyclic group include a pyridine group, a pyrrole group, a pyrimidine group, a quinoline group, a pyridazine group, a furan group, a thiophene group, an imidazole group, a pyrazole group, a dibenzofuran group, a dibenzothiophene group, A carbazole group, a benzocarbazole group, a benzonaphthofuran group, a benzonaphthothiophene group, an indenocarbazole group, an indolocarbazole group, etc., but are not limited thereto.

In the present specification, the description of the above-mentioned heterocyclic group may be applied except that the heteroaryl group is aromatic.

In the present specification, the amine group is -NH ₂ ; an alkylamine group; N-alkylarylamine group; arylamine group; N-aryl heteroarylamine group; It may be selected from the group consisting of an N-alkylheteroarylamine group and a heteroarylamine group, and the number of carbon atoms is not particularly limited, but is preferably 1 to 30. Specific examples of the amine group include a methylamine group, a dimethylamine group, an ethylamine group, a diethylamine group, a phenylamine group, a naphthylamine group, a biphenylamine group, an anthracenylamine group, and a 9-methyl-anthracenylamine group. , diphenylamine group, N-phenylnaphthylamine group, ditolylamine group, N-phenyltolylamine group, triphenylamine group, N-phenylbiphenylamine group, N-phenylnaphthylamine group, N-bi Phenylnaphthylamine group, N-naphthylfluorenylamine group, N-phenylphenanthrenylamine group, N-biphenylphenanthrenylamine group, N-phenylfluorenylamine group, N-phenylterphenylamine group group, N-phenanthrenylfluorenylamine group, N-biphenylfluorenylamine group, and the like, but is not limited thereto.

In the present specification, the N-alkylarylamine group refers to an amine group in which an alkyl group and an aryl group are substituted with N of the amine group.

In the present specification, the N-arylheteroarylamine group refers to an amine group in which an aryl group and a heteroaryl group are substituted with N of the amine group.

In the present specification, the N-alkylheteroarylamine group refers to an amine group in which an alkyl group and a heteroaryl group are substituted with N of the amine group.

In the present specification, an alkylamine group; N-alkylarylamine group; arylamine group; N-aryl heteroarylamine group; The alkyl group, the aryl group and the heteroaryl group in the N-alkylheteroarylamine group and the heteroarylamine group are the same as the examples of the alkyl group, the aryl group and the heteroaryl group, respectively.

In the exemplary embodiment of the present specification, the aromatic compound may have any one of the following structures.

In the step of heating the reactor to proceed deuterium of the aromatic compound, the reactor is heated to a temperature of 150 °C or higher, 160 °C or higher, 170 °C or higher, 180 °C or higher, 190 °C or higher, 200 °C or higher, 210 °C or higher, or 220 °C or higher. It is a step of heating, and may also be a step of heating to a temperature of 250 ℃ or less, 240 ℃ or less, or 230 ℃ or less.

The step of heating the reactor to proceed deuterium of the aromatic compound may be a step of heating the reactor to a temperature of 220°C or higher and 250°C or lower. In this case, deuterium can be performed without activating the catalyst by supplying hydrogen. At this time, the pressure is lowered by the metal salt having a neutral acidity, so that a stable reaction can proceed at a high temperature.

At this time, the deuterium reaction time is reacted for 3 hours or more after the temperature rise is completed. Specifically, the deuterium reaction may be reacted for 3 hours or more and 24 hours or less after the temperature rise is completed, and preferably for 6 hours or more and 18 hours or less.

The method for producing a deuterated aromatic compound of the present specification further includes the step of obtaining the deuterated aromatic compound after the step of proceeding with the deuteration. The obtained method may be carried out by a method known in the art, and is not particularly limited.

The higher the deuterated substitution rate of the obtained deuterated aromatic compound, the better, specifically, the deuterium substitution rate of the obtained deuterated aromatic compound is 50% or more, 60% or more, 70% or more, 80% or more, 85% or more , 90% or more, 91% or more, 92% or more, 93% or more, 94% or more, 95% or more, 96% or more, 97% or more, 98% or more, 99% or more, or 100% or more.

The higher the purity of the obtained deuterated aromatic compound is, the better, specifically, the purity of the obtained deuterated aromatic compound is 90% or more, 91% or more, 92% or more, 93% or more, 94% or more, 95% or more. % or more, 96% or more, 97% or more, 98% or more, 99% or more, or 100%.

The present specification provides a deuterated aromatic compound prepared by the above-described preparation method.

In an exemplary embodiment of the present specification, the deuterated aromatic compound refers to an aromatic compound substituted with at least one deuterium.

The present specification provides an organic light emitting device including the deuterated aromatic compound described above.

In an exemplary embodiment of the present specification, the organic light emitting device includes a first electrode; a second electrode provided to face the first electrode; and an organic material layer provided between the first electrode and the second electrode, wherein the organic material layer includes the deuterated aromatic compound.

In the exemplary embodiment of the present specification, the organic material layer includes a light emitting layer including the deuterated aromatic compound.

The organic material layer of the organic light emitting device of the present specification may have a single-layer structure, but may have a multi-layer structure in which two or more organic material layers are stacked. For example, the organic material layer of the present specification may be composed of 1 to 3 layers. In addition, the organic light emitting device of the present specification may have a structure including a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, an electron injection layer, etc. as an organic material layer. However, the structure of the organic light emitting device is not limited thereto and may include a smaller number of organic layers.

When the organic light emitting device includes a plurality of organic material layers, the organic material layers may be formed of the same material or different materials.

For example, the organic light emitting device of the present specification may be manufactured by sequentially stacking an anode, an organic material layer, and a cathode on a substrate. At this time, by using a PVD (physical vapor deposition) method such as sputtering or e-beam evaporation, a metal or conductive metal oxide or an alloy thereof is deposited on a substrate to form an anode. and forming an organic material layer including a hole injection layer, a hole transport layer, a light emitting layer and an electron transport layer thereon, and then depositing a material that can be used as a cathode thereon. In addition to this method, an organic light emitting device may be manufactured by sequentially depositing a cathode material, an organic material layer, and an anode material on a substrate.

In addition, the compound of Formula 1 may be formed as an organic material layer by a solution coating method as well as a vacuum deposition method when manufacturing an organic light emitting device. Here, the solution coating method refers to spin coating, dip coating, doctor blading, inkjet printing, screen printing, spraying, roll coating, and the like, but is not limited thereto.

In the exemplary embodiment of the present specification, the first electrode is an anode, and the second electrode is a cathode.

According to another exemplary embodiment, the first electrode is a cathode, and the second electrode is an anode.

In another exemplary embodiment, the organic light emitting device may be a normal type organic light emitting device in which an anode, one or more organic material layers, and a cathode are sequentially stacked on a substrate.

In another exemplary embodiment, the organic light emitting device may be an inverted type organic light emitting device in which a cathode, one or more organic material layers, and an anode are sequentially stacked on a substrate.

In the present specification, the material of the negative electrode, the organic material layer and the positive electrode is not particularly limited except for including a deuterated aromatic compound in at least one layer of the organic material layer, and a material known in the art may be used.

Hereinafter, the present specification will be described in more detail through examples. However, the following examples are only for illustrating the present specification, and not for limiting the present specification.

[Example]

[Example 1]

1 g of naphthalene, 15 ml of heavy water (D ₂ O), 0.5 g of Pt/C (the content of Pt in the catalyst is 10 wt %) and 10 g of calcium chloride were placed in a high-pressure reactor, and the head of the reactor was covered to seal the inside of the reactor. . Argon was blown into the reaction mass for about 5 minutes while stirring. Then, the reaction was carried out at a temperature of 220 °C for 18 hours. After the deuterium substitution reaction is completed, the temperature is lowered, and 15 ml of methylene chloride and 50 ml of water are added and stirred, followed by filtering to remove the catalyst. Here, only the organic solvent layer was separated _{, and the residual moisture was removed using magnesium sulfate (MgSO 4} ), filtered, and then the solvent was removed using a rotary evaporator to obtain deuterium-substituted naphthalene.

At this time, as a result of separately dissolving calcium chloride in distilled water and contacting the pH paper, it was confirmed that it was neutral at 6-7.

[Example 2]

Using the same method as in Example 1, potassium bromide (potassium bromide) was added instead of calcium chloride to perform a deuterium substitution reaction to obtain naphthalene substituted with deuterium.

At this time, as a result of separately dissolving potassium bromide in distilled water and contacting the pH paper, it was confirmed that it was neutral at 6-7.

[Example 3]

Anthracene substituted with deuterium was obtained by performing a deuterium substitution reaction for anthracene instead of naphthalene by using the same method as in Example 1.

[Example 4]

Using the same method as in Example 3, potassium bromide was added instead of calcium chloride to perform a deuterium substitution reaction for anthracene to obtain anthracene substituted with deuterium.

[Example 5]

The same method as in Example 3 was used, except that sodium sulfate was added instead of calcium chloride to carry out a deuterium substitution reaction for anthracene to obtain anthracene substituted with deuterium.

At this time, as a result of separately dissolving sodium sulfate in distilled water and contacting the pH paper, it was confirmed that it was neutral at 6-7.

[Comparative Example 1]

1 g of naphthalene, 15 ml of heavy water (D ₂ O), and 0.5 g of Pt/C (the content of Pt in the catalyst is 10 wt %) were put into the high-pressure reactor, and the head of the reactor was covered to seal the inside of the reactor. Argon was blown into the reaction mass for about 5 minutes while stirring. Then, the reaction was carried out at a temperature of 220 °C for 18 hours. After the deuterium substitution reaction is completed, the temperature is lowered, 15 ml of methylene chloride is added and stirred, and the catalyst is removed by filtering. Thereafter, only the organic solvent layer was separated and _{residual moisture was removed using MgSO 4} , filtered, and then the solvent was removed using a rotary evaporator to obtain deuterium-substituted naphthalene.

[Comparative Example 2]

Anthracene substituted with deuterium was obtained by performing a deuterium substitution reaction for anthracene instead of naphthalene by using the same method as in Comparative Example 1.

[Experimental example]

The reaction pressure and deuterium substitution rate for Examples 1 to 5 and Comparative Examples 1 to 2 were measured, and the results are shown in Tables 1 to 3 below.

An internal standard dissolved in the same solvent for NMR measurement by quantifying the sample after the deuteration reaction has been completed and quantifying the sample sample dissolved in the solvent for NMR measurement, and quantifying any compound that does not overlap the peak with the compound before the deuteration reaction in the same amount as the sample samples were prepared. NMR measurement graphs were obtained using ¹ H-NMR for each of the prepared sample sample and the internal standard sample.

^{When 1} H-NMR peak was assigned (assigned), the internal standard peak was set to 1 to obtain a relative integration value for each position of the sample after the deuteration reaction was completed.

If deuterium is substituted at all positions in the sample after the deuterium reaction is completed, no peak related to hydrogen appears at all, and in this case, it is determined that the deuterium substitution rate is 100%. On the other hand, if hydrogens at all positions are not substituted with deuterium, a peak of hydrogen not substituted with deuterium appears.

Based on this, in this experiment, the deuterium substitution rate is the integral value of the peak related to hydrogen in the NMR measurement graph of the internal standard sample in which deuterium is not substituted, and the integral value of the peak due to the unsubstituted hydrogen in the NMR measurement graph of the sample sample. to find the value minus This value is a relative integration value for each position, and does not appear as a corresponding peak because it is substituted with deuterium, and represents a ratio substituted with deuterium.

Then, ^{the weight of the sample used to make the 1} H-NMR measurement sample, the weight of the internal standard, and the relative integral value were used to calculate the substitution rate for each position of the sample.

reactant metal salt reaction pressure
(bar) heavy hydrogen
Substitution rate (%) Example 1 naphthalene calcium chloride 3.4 93 Example 2 naphthalene potassium bromide 3.9 94 Example 3 anthracene calcium chloride 3.2 95 Example 4 anthracene potassium bromide 3.5 94 Example 5 anthracene sodium sulfate 4.1 95 Comparative Example 1 naphthalene - 22.5 94 Comparative Example 2 anthracene - 21.8 95

Through Table 1, it was confirmed that, as in Examples 1 to 5, when a metal salt having a neutral acidity was added, the reaction pressure could be significantly lowered while maintaining the deuterium substitution ratio.

Claims (5)

preparing a solution containing a deuterium source, a metal catalyst, a metal salt having neutral acidity, and an aromatic compound including one or more aromatic rings; and
A method for producing a deuterated aromatic compound comprising the step of heating the solution to advance the deuterated reaction of the aromatic compound. The method according to claim 1, wherein the pH of the metal salt having a neutral acidity is 6.5 to 7.5. The method according to claim 1, wherein the metal salt having a neutral acidity is a metal salt containing an anion derived from a strong acid and a cation derived from a strong base. The method according to claim 1, wherein the cation of the metal salt having a neutral acidity is selected from lithium ion, sodium ion, potassium ion, rubidium ion, cesium ion, calcium ion, strontium ion and barium ion. The method according to claim 1, wherein the anion of the metal salt having a neutral acidity is a chlorine ion, an iodine ion, a bromine ion, SO ₄ ^2-, and CF ₃ SO ₃ ^{− The} method for producing a deuterated aromatic compound.