A preparation method of organic luminescent material intermediate 8-bromophenanthrene-1-trifluoromethanesulfonate

Abstract

The present application provides a preparation method of an organic light-emitting material intermediate 8-bromophenanthrene-1-trifluoromethanesulfonate, which belongs to the technical field of organic light-emitting materials. The present invention uses 1-amino-5-bromonaphthalene as raw material, and first condenses with acetic anhydride to obtain 1-acetamido-5-bromonaphthalene; then 9-BBN and 1-butyl butyl butyl ester are coupled to prepare (5-acetamidonaphthalene)-4-tert-butyl butyrate; then (5-acetamidonaphthalene)-4-butyric acid is prepared by trifluoroacetic acid hydrolysis; then Eaton's reagent is used for dehydration ring closure to prepare N-(8-oxo-5,6,7,8-tetrahydrothiophene-1-yl)acetamide; then 8-amino-3,4-dihydrothiophene-1(2H)-one is prepared by hydrolysis; then 8-bromophenanthrene-1-ol is prepared by diazotization and oxidation reaction; finally, the product 8-bromophenanthrene-1-trifluoromethanesulfonate is prepared by reaction with trifluoromethanesulfonic anhydride. The above-mentioned preparation method has cheap and readily available raw materials, simple process operation, no need for column chromatography purification, high yield, and is suitable for industrial production.

Description

Technical Field

[0001] The present invention relates to the field of organic luminescent materials, and in particular to an organic luminescent material intermediate 8-bromo

[0002] A method for preparing phenanthrene-1-trifluoromethanesulfonate. Background Art

[0003] 8-Bromophenanthrene-1-trifluoromethanesulfonate is an important intermediate of organic light-emitting materials. Its chemical structure is shown below:

[0004] ;

[0005] After searching, it was found that there is no public technology for the synthesis of this target compound.

[0006] Therefore, 8-bromophenanthrene-1-trifluoromethanesulfonate, as an important intermediate of organic light-emitting materials, still needs to develop a new route with high efficiency, good stability and suitability for industrial production, in order to have good applications in the field of light-emitting materials in OLEDs and organic electronic devices. Summary of the Invention

[0007] In order to solve the problems in the prior art, the present application provides a method for preparing 8-bromophenanthrene-1-trifluoromethanesulfonate.

[0008] The present invention provides a synthetic route of 8-bromophenanthrene-1-trifluoromethanesulfonate as follows:

[0009]

[0010] To achieve the above object, the present invention adopts the following technical solutions:

[0011] One of the technical solutions of the present invention provides a method for preparing 8-bromophenanthrene-1-trifluoromethanesulfonate, comprising the following steps:

[0012] Step 1: 1-amino-5-bromonaphthalene and acetic anhydride are subjected to a condensation reaction to prepare 1-acetamido-5-bromonaphthalene;

[0013] Step 2: 9-BBN is first reacted with tert-butyl 1-butenoate, and then coupled with 1-acetylamino-5-bromonaphthalene in the presence of a solvent, palladium, and a base to prepare (5-acetylaminonaphthalene)-4-butyric acid tert-butyl ester;

[0014] Step 3: (5-acetylaminonaphthalene)-4-butyric acid tert-butyl ester is hydrolyzed in the presence of trifluoroacetic acid to obtain (5-acetylaminonaphthalene)-4-butyric acid;

[0015] Step 4: (5-Acetylaminonaphthalene)-4-butyric acid is dehydrated and cyclized in Eaton's reagent to prepare N-(8-oxo-5,6,7,8-tetrahydrothiophen-1-yl)acetamide;

[0016] Step 5: N-(8-oxo-5,6,7,8-tetrahydrothiophen-1-yl)acetamide is hydrolyzed in concentrated hydrochloric acid methanol solution to prepare 8-amino-3,4-dihydrothiophen-1(2H)-one;

[0017] Step 6: 8-amino-3,4-dihydrothiophen-1(2H)-one is subjected to diazotization reaction to prepare 8-bromo-3,4-dihydrothiophen-1(2H)-one;

[0018] Step 7: 8-bromo-3,4-dihydrothiophen-1(2H)-one is oxidized with Oxone reagent to prepare 8-bromophenanthren-1-ol;

[0019] Step 8: 8-bromophenanthrene-1-ol is reacted with trifluoromethanesulfonic anhydride to prepare 8-bromophenanthrene-1-trifluoromethanesulfonate.

[0020] In some embodiments, in step 1, the reaction solvent is selected from dichloromethane and tetrahydrofuran.

[0021] In some embodiments, in step 1, the molar ratio of 1-amino-5-bromonaphthalene to acetic anhydride is 1:1 to 1:3; in some embodiments, in step 1, the molar ratio of 1-amino-5-bromonaphthalene to acetic anhydride is 1:1.2, 1:1.5, 1:2, or 1:2.5.

[0022] In some embodiments, in step 1, the reaction temperature is controlled between 0°C and 10°C, and the reaction time is 1-5 hours.

[0023] In some embodiments, in step 2, the catalyst is selected from Pd(PPh3)4 and DPPF PdCl2

[0024] One of them.

[0025] In some embodiments, in step 2, the base is selected from one of sodium methoxide, potassium carbonate and sodium carbonate.

[0026] In some embodiments, in step 2, the solvent is selected from tetrahydrofuran, 1,4-dioxane

[0027] At least one of.

[0028] In some embodiments, in step 2, the solvent is water and tetrahydrofuran in a volume ratio of 1:4.

[0029] of mixed solution.

[0030] In some embodiments, in step 2, a certain amount of water (water and tetrahydrofuran) is added to the reaction system.

[0031] The volume ratio is 1:4) which helps to improve the reaction yield.

[0032] The inventors found that when the substrate used was methyl 1-butenoate, the reaction could also obtain the corresponding coupling product with a yield of 85%.

[0033] In some embodiments, in step 2, the reaction temperature is controlled between 70° C. and 80° C., and the reaction time is 4-8 hours.

[0034] In some embodiments, in step 3, the reaction solvent is selected from at least one of dichloromethane and tetrahydrofuran.

[0035] In some embodiments, in step 3, the volume ratio of trifluoroacetic acid to the reaction solvent is 1:1 to 1:5. In some embodiments, in step 3, the volume ratio of trifluoroacetic acid to the reaction solvent is 1:4.

[0036] In some embodiments, in step 4, the inventors discovered that the dehydration ring-closure reaction is carried out by directly reacting (5-acetylaminonaphthalene)-4-butyric acid in Eaton's reagent. If the acid is dissolved in dichloromethane and then added to Eaton's reagent, the reaction rate is slower.

[0037] In some embodiments, in step 5, the reaction temperature is 60° C. to 100° C. In some embodiments, in step 5, the reaction temperature is 80° C. and the reaction time is 1 hour.

[0038] In some embodiments, the diazotization reaction in step six is ​​carried out in the presence of sodium nitrite solution, hydrobromic acid and CuBr.

[0039] Furthermore, the diazotization reaction in step six is ​​carried out in the presence of sodium nitrite solution (30% in H2O), hydrobromic acid and CuBr.

[0040] In some embodiments, in step 7, the molar ratio of 8-bromo-3,4-dihydrothiophen-1(2H)-one to the Oxone reagent is 1:1 to 1:2. In some embodiments, in step 7, the molar ratio of 8-bromo-3,4-dihydrothiophen-1(2H)-one to the Oxone reagent is 1:1.1.

[0041] In some embodiments, in step 7, the solvent used is selected from at least one of dichloromethane and tetrahydrofuran.

[0042] In some embodiments, in step 7, NH4Br may be further added to the reaction.

[0043] The inventors found that in step seven, the addition of 1.1 equivalents of NH4Br facilitated the conversion of the reaction.

[0044] In some embodiments, in step eight, the molar ratio of 8-bromophenanthren-1-ol to trifluoromethanesulfonic anhydride is 1:1.0 to 1:2. In some embodiments, in step eight, the molar ratio of 8-bromophenanthren-1-ol to trifluoromethanesulfonic anhydride is 1:1.5. In some embodiments, in step eight, the solvent used is dichloromethane, the base used is triethylamine, the reaction temperature is controlled between 0°C and 10°C, and the reaction time is 2 hours.

[0045] The invention uses 1-amino-5-bromonaphthalene as a raw material and synthesizes 8-bromophenanthrene-1-trifluoromethanesulfonate through the reaction steps of condensation, coupling, hydrolysis, ring closure, hydrolysis, diazotization, oxidation, substitution and the like.

[0046] Compared with the existing synthesis method, the present invention has the following advantages:

[0047] The invention discloses the preparation process of 8-bromophenanthrene-1-trifluoromethanesulfonate for the first time. The reaction operation is simple, and the yield of each step reaches more than 90%, the total yield is high, the production cost is low, the post-treatment avoids the use of column chromatography purification, the post-treatment process is simple, and industrial scale-up production is easy.

[0048] In the description of this specification, the reference terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and features of different embodiments or examples without contradiction. DETAILED DESCRIPTION

[0049] In order to enable those skilled in the art to better understand the technical solutions of the present invention, some non-limiting embodiments are further disclosed below to further illustrate the present invention in detail.

[0050] The reagents used in the present invention can be purchased from the market or prepared by the method described in the present invention.

[0051] In the present invention, min means minute; h means hour; g means gram; mL means milliliter; and mg means milligram.

[0052] In the present invention, 9-BBN represents 9-borabicyclo[3.3.1]nonane.

[0053] In the present invention, Oxone reagent refers to potassium persulfate complex salt.

[0054] In the present invention, Eaton's reagent refers to phosphorus pentoxide methanesulfonic acid.

[0055] Example 1

[0056] Synthesis of 1-acetylamino-5-bromonaphthalene

[0057]

[0058] In a three-necked flask, compound 1 (500 g, 2.25 mol) was dissolved in DCM (1.5 L). Acetic anhydride (275.8 g, 2.70 mol) was slowly added dropwise under an ice bath. After complete addition, the mixture was returned to room temperature and stirred for 2 hours to precipitate a solid. The reaction was quenched with water, filtered, and washed with dichloromethane. The resulting solid was dried to obtain compound 2 (582.7 g) in a 98% yield.

[0059] 1 H NMR (400 MHz, DMSO-d6) δ 10.04 (s, 1H), 7.74 – 7.66 (m, 6H).8.13(d, 1H), 8.00 (d, 1H), 7.92 (dd, 1H), 7.77 (d, 1H), 7.66 (dd, 1H), 7.47 (dd,1H), 2.19 (s, 3H).

[0060] Synthesis of tert-butyl (5-acetylaminonaphthalene)-4-butyrate

[0061]

[0062] A 50 L reactor was charged with 9-BBN (4406.3 ml, 2.20 mol, 0.5N in THF) and compound 3 (313.2 g, 2.20 mol). After stirring at room temperature for 1 hour, compound 2 (530 g, 2.00 mol), sodium methoxide (216.1 g, 4.00 mol), tetrahydrofuran (2.5 L), and Pd(PPh3)4 (0.07 g, 0.06 mol) were added. The atmosphere was replaced with nitrogen three times, and the temperature was slowly raised to 80°C and stirred for 6 hours. After returning to room temperature, the aqueous phase was removed, and the organic phase was filtered through a silica gel pad to remove residual palladium. The organic phase was then concentrated under reduced pressure to remove tetrahydrofuran, and finally slurried with petroleum ether to obtain an off-white solid (590.2 g) in a 90% yield.

[0063] 1H NMR (400 MHz, DMSO-d6) δ 9.90 (s, 1H), 7.98 – 7.91 (m, 2H), 7.64(d, 1H), 7.48 (ddd, 2H), 7.37 (dd, 1H), 3.08 – 3.00 (t, 2H), 2.30 (t, 2H), 2.17 (s, 3H), 1.87 (m, 2H), 1.41 (s, 9H).

[0064] Synthesis of (5-acetylaminonaphthalene)-4-butyric acid

[0065]

[0066] Compound 4 (500 g, 1.53 mol) was dissolved in DCM (2.5 L) in a three-necked flask. Trifluoroacetic acid (625 ml) was slowly added dropwise in an ice bath. After complete addition, the mixture was returned to room temperature and stirred for 10 hours. The trifluoroacetic acid and DCM were removed by vacuum concentration. Water (1 L) and DCM (1 L) were added to precipitate a solid, which was filtered and slurried with dichloromethane to obtain solid compound 5 (393.6 g) in a 95% yield.

[0067] 1 H NMR (400 MHz, DMSO-d6) δ 9.92 (s, 1H), 7.96 (t, 2H), 7.64 (d, 1H), 7.48 (ddd, 2H), 7.37 (d, 1H), 3.11 – 3.01 (t, 2H), 2.33 (t, 2H), 2.18 (s,3H), 1.95 – 1.80 (m, 2H).

[0068] Synthesis of N-(8-oxo-5,6,7,8-tetrahydrothiophen-1-yl)acetamide

[0069]

[0070] In a three-necked flask, compound 5 (300 g, 1.10 mol) was dissolved in Eaton's reagent (1.2 L) and stirred at room temperature for 6 hours. The reaction was quenched by adding ice water to precipitate a solid, which was filtered and slurried with dichloromethane to obtain solid compound 6 (266.1 g) in a 95% yield.

[0071] 1H NMR (400 MHz, DMSO-d6) δ 10.05 (s, 1H), 8.08 (d, 1H), 8.03 (d,1H), 7.96 (d, 1H), 7.82 (, 1H), 7.66 – 7.58 (t, 1H), 3.37 (t, 2H), 2.67 (t,2H), 2.18 (m, 5H).

[0072] Synthesis of 8-amino-3,4-dihydrothiophen-1(2H)-one

[0073]

[0074] In a three-necked flask, compound 6 (250 g, 1.10 mol) was dissolved in methanol (2.5 L). Concentrated hydrochloric acid (500 ml) was slowly added, and the temperature was slowly raised to 80°C and refluxed for 2 hours. After returning to room temperature, saturated sodium bicarbonate solution was added for neutralization, and ethyl acetate was added for extraction. The organic phase was concentrated to obtain compound 7 (198.1 g) as a pale yellow solid in a 95% yield.

[0075] 1H NMR (400 MHz, Chloroform-d) δ 8.07 (d, 1H), 7.76 (d, 1H), 7.59(dt, 1H), 7.39 (dd, 1H), 6.91 (d, 1H), 3.36 (t, 2H), 2.73 (t, 2H), 2.29 (m,2H).

[0076] Synthesis of 8-bromo-3,4-dihydrothiophen-1(2H)-one

[0077]

[0078] In a three-necked flask, compound 7 (180 g, 0.85 mol) was dissolved in acetonitrile (2 L). Water (1.8 L) and HBr (1.8 L) were added. After cooling to 0°C, NaNO2 solution (88.2 g, 1.28 mol, 30% in H2O) was slowly added. After stirring in an ice bath for 1 hour, CuBr (487.7 g, 3.4 mol) was slowly added. The mixture was returned to room temperature and stirred for 10 hours. After the reaction was complete, the mixture was filtered through a silica gel pad and extracted with ethyl acetate. The organic phase was concentrated and then directly slurried with petroleum ether to obtain compound 8 (200.0 g) as a white solid in an 85% yield.

[0079] 1H NMR (400 MHz, Chloroform-d) δ 8.20 (s, 2H), 8.13 (d, 1H), 7.91 (d,1H), 7.43 (t, 1H), 3.39 (t, 2H), 2.78 – 2.71 (t, 2H), 2.31 (m, 2H).

[0080] Synthesis of 8-bromophenanthren-1-ol

[0081]

[0082] In a three-necked flask, compound 8 (200 g, 0.73 mol) was dissolved in DCM (2 L). NH4Br (78.4 g, 0.80 mol) and Oxone (277.0 g, 0.80 mol) were slowly added and stirred at room temperature for 12 hours. The reaction was quenched by adding water and extracted with DCM. The organic phase was concentrated and then directly slurried with petroleum ether to obtain compound 9 (178.7 g) as a white solid in a 90% yield.

[0083] 1H NMR (400 MHz, DMSO-d6) δ 8.83 (d, 1H), 8.27 (m, 2H), 8.03 (d, 1H), 7.97 (d, 1H), 7.55 (m, 2H), 7.15 (d, 1H).

[0084] Synthesis of 8-bromophenanthrene-1-trifluoromethanesulfonate

[0085]

[0086] In a three-necked flask, compound 9 (150 g, 0.55 mol) was dissolved in DCM (1.5 L). Triethylamine (114 ml, 0.82 mol) was added. Trifluoromethanesulfonic anhydride (231.4 g, 0.82 mol) was slowly added dropwise in an ice bath. After the addition was complete, the mixture was returned to room temperature and stirred for 2 hours. Water was added to quench the reaction, and the mixture was extracted with ethyl acetate. The organic phase was concentrated under reduced pressure to obtain compound 10 (211.7 g) as an off-white solid in a 95% yield.

[0087] 1H NMR (400 MHz, Chloroform-d) δ 8.70 (d, 1H), 8.66 (d, 1H), 8.39 (d,1H), 8.09 (d, 1H), 7.96 (d, 1H), 7.71 (t, 1H), 7.62 (d, 1H), 7.56 (t, 1H).

[0088] Investigation of reaction conditions

[0089] Example 2

[0090] According to the method in Example 1, the effects of various process parameters on the reactions of each step were investigated, and the results are shown in the following table.

[0091] In step 2, synthesis of tert-butyl (5-acetylaminonaphthalene)-4-butyrate: keeping other reaction conditions unchanged, the effects of catalyst, base, and solvent on the reaction were investigated. The results are shown in the following table:

[0092]

[0093] In step 4, the synthesis of N-(8-oxo-5,6,7,8-tetrahydrothiophen-1-yl)acetamide: keeping other reaction conditions unchanged, the effect of the addition method of Eaton's reagent on the reaction was investigated. The results are shown in the following table:

[0094]

[0095] In step 7, the synthesis of 8-bromophenanthren-1-ol: keeping other reaction conditions unchanged, the effects of the solvent and whether or not NH4Br was added in the oxidation reaction on the reaction were investigated. The results are shown in the following table:

[0096]

[0097] The methods of the present invention have been described through preferred embodiments. It is apparent that those skilled in the art will be able to modify or appropriately alter and combine the methods and applications described herein within the scope, spirit, and spirit of the present invention to implement and apply the technology of the present invention. Those skilled in the art may refer to the disclosure herein and appropriately modify the process parameters to achieve the desired effect. It is particularly important to note that all similar substitutions and modifications apparent to those skilled in the art are considered encompassed by the present invention.

Claims

1. A method for preparing 8-bromophenanthrene-1-trifluoromethanesulfonate, wherein the reaction process is as follows: ； It is characterized by: The following steps are involved: Step 1: 1-amino-5-bromonaphthalene and acetic anhydride are subjected to a condensation reaction to prepare 1-acetamido-5-bromonaphthalene; Step 2: 9-BBN is first reacted with tert-butyl 1-butenoate, and then coupled with 1-acetylamino-5-bromonaphthalene in the presence of a solvent, a palladium catalyst, and a base to prepare (5-acetylaminonaphthalene)-4-butyric acid tert-butyl ester; Step 3: (5-acetylaminonaphthalene)-4-butyric acid tert-butyl ester is hydrolyzed in the presence of trifluoroacetic acid to obtain (5-acetylaminonaphthalene)-4-butyric acid; Step 4: (5-Acetylaminonaphthalene)-4-butyric acid is dehydrated and cyclized in Eaton's reagent to prepare N-(8-oxo-5,6,7,8-tetrahydrothiophen-1-yl)acetamide; Step 5: N-(8-oxo-5,6,7,8-tetrahydrothiophen-1-yl)acetamide is hydrolyzed in concentrated hydrochloric acid methanol solution to prepare 8-amino-3,4-dihydrothiophen-1(2H)-one; Step 6: 8-amino-3,4-dihydrothiophen-1(2H)-one is subjected to diazotization reaction to prepare 8-bromo-3,4-dihydrothiophen-1(2H)-one; Step 7: 8-bromo-3,4-dihydrothiophen-1(2H)-one is oxidized with Oxone reagent to prepare 8-bromophenanthren-1-ol; Step 8: 8-bromophenanthrene-1-ol reacts with trifluoromethanesulfonic anhydride to prepare 8-bromophenanthrene-1-trifluoromethanesulfonate; The palladium catalyst is selected from one of Pd(PPh3)4 and DPPF PdCl2.

2. The preparation method according to claim 1, characterized in that In step 2, the base is selected from one of sodium methoxide, potassium carbonate and sodium carbonate.

3. The preparation method according to claim 1, characterized in that In step 2, the reaction temperature is controlled between 70° C. and 80° C., and the reaction time is 4-8 hours.

4. The preparation method according to claim 1, characterized in that In step 2, the reaction solvent is selected from at least one of tetrahydrofuran and 1,4-dioxane.

5. The preparation method according to claim 4, characterized in that In step 2, the solvent is a mixed solution of water and tetrahydrofuran in a volume ratio of 1:

4.

6. The preparation method according to claim 1, characterized in that In step 4, the reaction is carried out directly with (5-acetylaminonaphthalene)-4-butyric acid in Eaton's reagent.

7. The preparation method according to claim 1, characterized in that The diazotization reaction in step six is ​​carried out in the presence of sodium nitrite solution, hydrobromic acid and CuBr.

8. The preparation method according to claim 1, characterized in that In step 7, the molar ratio of 8-bromo-3,4-dihydrothiophen-1(2H)-one to Oxone reagent is 1:1 to 1:

2.

9. The preparation method according to claim 1, characterized in that In step seven, NH4Br may be further added to the reaction.

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