A sulfur-containing high-refractive-index curable monomer

Abstract

The present invention discloses a novel sulfur-containing high-refractive-index curable monomer, which has the chemical structure of Formula I or Formula II as follows: wherein, X 1 is a polymerizable group, and X 2 is a high-refractive-index performance group. According to the synthesis route proposed by the present invention, starting from different primary amino group-containing high-refractive-index raw materials (such as benzene ring, naphthalene ring, diphenyl sulfide, bisphenol fluorene, etc.), through episulfide ring-opening reaction, thio-CDI ring-closing and esterification reaction, the amino group-containing high-refractive-index group is connected to acrylate through a thiazoline structure, thereby endowing the monomer with a high refractive index. In addition, the sulfur-containing high-refractive-index curable monomer of the present invention has good compatibility with common photocurable monomers (TPGDA), expands the application of this type of high-refractive-index monomer, and has good industrial application prospects.

Description

Technical Field

[0001] The present invention relates to the technical fields of molecular structure design and organic compound synthesis, and particularly relates to a sulfur-containing high-refractive-index curable monomer. Background Art

[0002] High-refractive-index materials have a wide range of applications in many aspects such as high-end display devices, optical adhesives, optical waveguides, antireflection coatings, charge-coupled devices, and image sensors. Compared with inorganic materials, high-refractive-index resins have advantages such as good impact resistance, easy processing, dyeability, and light weight, and generally require a refractive index higher than 1.6. Sulfur-containing high-refractive-index materials have received increasing attention due to their high refractive index, high Abbe number, and good light transmittance. Currently reported sulfur-containing high-refractive-index monomers include thiadiazole-based, phenyl sulfide-based, thiophene-based, alkyl sulfide-based, etc. For example, Patent CN101481360 proposes a high-refractive-index monomer containing a thiadiazole structure, but this monomer contains only one thiadiazole five-membered ring and has a low sulfur content, which limits the refractive index of the monomer (the highest refractive index of this series of compounds is only 1.6). Patent CN115894315A reports a high-refractive-index monomer with a disulfide structure. By introducing the disulfide structure, the refractive index of the monomer is increased, and the highest refractive index can reach 1.698. However, generally speaking, the disulfide structure in the molecule belongs to a weak bond structure and is prone to decomposition when used in an acidic, alkaline, or high-temperature environment for a long time, affecting the stability of the material. Therefore, to a certain extent, its application is limited. Generally speaking, there are relatively few overall reports on current research related to high-refractive-index monomers. Therefore, it is very meaningful to develop photocurable monomers with low viscosity or good solubility and high refractive index. Summary of the Invention

[0003] (1) Technical Problems to be Solved

[0004] In order to overcome the deficiencies of the prior art, a sulfur-containing high-refractive-index curable monomer is proposed, which has the advantages of high refractive index and good solubility.

[0005] (2) Technical Solutions

[0006] The present invention is realized through the following technical solutions: The present invention proposes a sulfur-containing high-refractive-index curable monomer having the following chemical structure of Formula I or Formula II:

[0007]

[0008] Further, the in Formula I and Formula II can be replaced by .

[0009] Further, the X 1 is one of acrylate or methacrylate structures.

[0010] Further, the X 2 is specifically one of the following chemical structures:

[0011]

[0012] (III) Beneficial effects

[0013] The present invention has the following beneficial effects compared with the prior art:

[0014] A sulfur-containing high-refractive-index curable monomer mentioned in the present invention, according to the synthesis route proposed by the present invention, can start from different primary amino group-containing high-refractive-index raw materials (such as benzene ring, naphthalene ring, diphenyl sulfide, bisphenol fluorene, etc.), through episulfide ring-opening reaction, thio-CDI ring-closure and esterification reaction, connect the amino group-containing high-refractive-index group to acrylate through a thiazoline structure, thereby endowing the monomer with a high refractive index. In addition, the sulfur-containing high-refractive-index curable monomer described in the present invention has good compatibility with common photocurable monomers (TPGDA), expands the application of this type of high-refractive-index monomer, and has good industrial application prospects. Specific embodiments

[0015] In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below with reference to embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0016] The sulfur-containing high-refractive-index curable monomer mentioned in the present invention has the chemical structure of Formula I or Formula II as follows:

[0017]

[0018] Based on the above chemical formula, the in Formula I and Formula II can also be to replace the sulfur-containing high-refractive-index curable monomer.

[0019] Therefore, as an embodiment, the sulfur-containing high-refractive-index curable monomer described in the present invention can be the following compounds:

[0020]

[0021]

[0022] Example 1

[0023] The synthesis route of Compound 1 is as follows:

[0024]

[0025] The synthesis process of Compound 1-iii is as follows:

[0026] Dissolve aniline (93.1 g, 1 mol) and DBU (15.2 g, 0.1 mol) in DMF (500 mL). Slowly add epichlorohydrin (120 g, 1.1 mol) dropwise to the solution at room temperature. After the addition is complete, continue stirring for 2 hours. After the reaction is completed, quench the reaction solution into saturated ammonium chloride aqueous solution (1 L), extract with methyl tert-butyl ether 3 times. Combine the organic phases, wash with saturated brine, dry over anhydrous sodium sulfate, filter, and concentrate under reduced pressure to obtain 210 g of crude product, which is directly used for the next reaction.

[0027] (2) The synthesis process of compound 1-iv is as follows:

[0028] Dissolve compound 1-iii (210 g, crude product) in anhydrous tetrahydrofuran (1 L). Slowly add thiocarbonyl diimidazole (196 g, 1.1 mol) at 0 °C. After the addition is complete, slowly raise the reaction solution to room temperature. After the reaction is completed, quench the reaction solution into saturated ammonium chloride aqueous solution (2 L), extract with methyl tert-butyl ether. Combine the organic phases, wash with saturated brine, dry over anhydrous sodium sulfate, filter, and separate the crude product by column chromatography to obtain 169 g of compound 1-v, with a yield of 69.3%.

[0029] Test the chemical structure of compound 1-v, and the NMR characterization results are as follows:

[0030] 1 H NMR (400 MHz, CDCl 3 ) δ: 7.30–7.26 (t, J = 8 Hz, 2H), 7.11–7.07 (t, J = 8 Hz, 1H), 6.93–6.91 (m, 2H), 4.14 - 3.89 (m, 2H), 3.81–3.57 (m, 2H), 3.08 (m, 1H);

[0031] (2) The synthesis process of compound 1 is as follows:

[0032] Dissolve p-methoxyphenol (860 mg, 6.9 mmol), compound 1-v (169 g, 0.69 mol) and methacrylic acid (119 g, 1.38 mol) in DMF at room temperature. Slowly add K 2 CO 3 (207 g, 1.5 mol) in batches. After the temperature stabilizes, slowly raise the temperature of the system to 50 °C and stir for 5 hours. After the reaction is completed, quench the reaction solution into water (300 mL), extract with methyl tert-butyl ether. Combine the organic phases, wash with saturated brine, dry over anhydrous sodium sulfate, filter, and separate the crude product by column chromatography to obtain 155 g of compound 1-v, with a yield of 80% and a refractive index of 1.620.

[0033] The chemical structure of Test Compound 1 was characterized by NMR, and the results are as follows:

[0034] 1 H NMR(400MHz,CDCl 3 )δ:7.36–7.32(t,J=8Hz,2H),7.15–7.11(t,J=8Hz,1H),6.97–6.94(m,2H),6.16(s,1H),5.64(s,1H),4.45–4.25(m,2H),4.16–4.12(m,1H),3.71–3.43(m,2H),1.96(s,3H)

[0035] Compound 7 can be obtained by reacting acrylic acid instead of methacrylic acid with Compound 1-v.

[0036] Example 2

[0037] The synthetic route of Compound 2 is as follows:

[0038]

[0039] The synthetic process of Compound 2-ii is the same as that of 1-iii

[0040] Compound 2-iii is the same as 1-v, with a refractive index of 1.650. The NMR characterization results are as follows:

[0041] 1 H NMR(400MHz,CDCl 3 )δ:7.55-7.51(m,2H),7.44–7.39(d,1H),7.23–7.18(t,1H),7.09–7.05(t,1H),6.79(s,1H),6.76–6.74(d,1H),6.18(s,1H),5.66(s,1H),4.51–4.33(m,2H),4.24–4.71(d,2H),3.76–3.55(m,1H),2.0(s,3H)

[0042] Example 3

[0043] The synthetic route of Compound 3 is as follows:

[0044]

[0045] The NMR characterization results of Compound 3 are

[0046] 1 H NMR(400MHz,CDCl 3)δ: 7.26 - 7.23 (m, 2H), 7.16–7.10 (m, 5H), 6.35–6.31 (m, 2H), 6.13 (s, 1H), 5.61 (s, 1H), 4.41–4.36 (m, 2H), 4.15–4.11 (m, 1H), 3.69–3.45 (m, 2H), 1.97 (s, 3H)

[0047] Example 4

[0048] The synthetic route of Compound 4 is as follows:

[0049]

[0050] The NMR characterization results of Compound 4 are as follows:

[0051] 1 H NMR (400 MHz, CDCl 3 )δ: 7.66–7.61 (d, 2H), 7.44–7.35 (m, 4H), 7.30–7.19 (m, 1H), 6.77–6.67 (d, 2H), 6.18 (s, 1H), 5.69 (s, 1H), 4.49–4.29 (m, 2H), 4.20–4.15 (m, 1H), 3.78–3.51 (m, 2H), 1.99 (s, 3H)

[0052] Example 5

[0053] The synthetic route of Compound 5 is as follows:

[0054]

[0055] The NMR characterization results of Compound 5 are as follows:

[0056] 1 H NMR (400 MHz, CDCl 3 )δ: 7.57 - 7.51 (m, 4H), 7.26 - 7.21 (m, 4H), 6.16 (s, 2H), 5.64 (s, 2H), 4.43–4.23 (m, 4H), 4.14–4.11 (m, 2H), 3.69–3.41 (m, 4H), 1.96 (s, 6H)

[0057] Example 6

[0058] The synthetic route of Compound 6 is as follows:

[0059]

[0060] The NMR characterization results of Compound 6 are as follows:

[0061] 1 H NMR (400 MHz, CDCl 3 ) δ: 7.83 (m, 2H), 7.35 - 7.31 (m, 6H), 6.76 (m, 4H), 6.40 (d, 4H), 6.19 (s, 2H), 5.67 (s, 2H), 4.48–4.41 (m, 4H), 4.19–4.15 (m, 2H), 3.75–3.49 (m, 4H), 2.01 (s, 6H)

[0062] Example 7

[0063] The synthetic route of Compound 13 is as follows:

[0064]

[0065] The synthetic process of Compound 13-ii is as follows:

[0066] At room temperature, KSCN (107 g, 1.1 mol) was slowly added to tetrahydrofuran (1 L) dissolved with 13-i (156.1 g, 1 mol). After the addition, the system was stirred overnight at room temperature. After the raw materials were consumed, the reaction solution was quenched into saturated brine (0.5 L), and extracted 3 times with ethyl acetate (300 mL). The organic phases were combined, dried over anhydrous sodium sulfate, and concentrated under reduced pressure to remove the solvent, obtaining 185 g of crude product directly used for the next step of the reaction

[0067] (2) The synthetic process of Compound 13-iii is as follows:

[0068] Aniline (89.4 g, 0.96 mol) and DBU (15.2 g, 0.1 mol) were dissolved in DMF (1 L). At 0 °C, Compound 13-ii (185 g, crude product, approximately 0.96 mol) was slowly added dropwise to the solution. After the addition, stirring was continued for 5 hours. After the reaction ended, the reaction solution was quenched into saturated ammonium chloride aqueous solution (1 L), and extracted 3 times with ethyl acetate. The combined organic phases were washed with saturated brine, dried over anhydrous sodium sulfate, filtered, concentrated under reduced pressure, and purified by column chromatography to obtain 200 g of Compound 13-iii. The total yield of the two steps was 75%.

[0069] (3) The synthetic process of Compound 13-iv is the same as that of Compound 1-v, and the yield after column chromatography purification is 85%.

[0070] (4) The synthetic process of Compound 13-v is as follows:

[0071] Compound 13-iv (227 g, 0.74 mol) and zinc chloride (13.6 g, 0.1 mol) were added to tetrahydrofuran (2 L). After stirring evenly, the system was cooled to 0 °C. At this temperature, NaBH was slowly added to the reaction solution in batches4 (38 g, 1 mol), After addition, the system was slowly warmed to room temperature and stirring was continued overnight. The reaction mixture was quenched into water and stirring was continued for 1 hour. After the excess NaBH 4 was completely decomposed, it was extracted with ethyl acetate. The combined organic phases were washed with saturated brine, dried over anhydrous sodium sulfate, filtered and concentrated to obtain 205 g of a crude product, which was directly used for the next step.

[0072] (5) Compound 13-v (205 g, crude product, about 0.73 mol) and triethylamine (110 g, 1.1 mol) were dissolved in dichloromethane (2 L). Methacryloyl chloride (110 g, 1.05 mol) was slowly added dropwise to the reaction mixture at 0 °C. After addition, stirring was continued for 2 hours, and then the reaction mixture was quenched into saturated ammonium chloride aqueous solution. It was extracted 3 times with ethyl acetate. The combined organic phases were washed with saturated brine, dried over anhydrous sodium sulfate, filtered and concentrated. The crude product was separated by column chromatography to obtain 203 g of compound 13, with a yield of 80%.

[0073] The NMR characterization results of compound 13 are as follows:

[0074] 1 H NMR (400 MHz, CDCl 3 ) δ: 7.35–7.31 (t, 2H), 7.14–7.10 (t, 1H), 6.95 - 6.92 (d, 2H), 6.12–6.09 (d, 1H), 5.61–5.57 (dd, 1H), 4.26–4.21 (m, 2H), 3.79–3.73 (m, 1H), 3.63–3.56 (m, 1H), 2.41–2.38 (m, 1H), 2.27–1.97 (m, 2H), 1.96–1.93 (d, 3H), 1.90–1.71 (m, 4H)

[0075] Example 8

[0076] The synthetic route of compound 17 is as follows:

[0077]

[0078] The NMR characterization results of compound 17 are as follows:

[0079] 1 H NMR (400 MHz, CDCl 3)δ: 7.55 - 7.51 (m, 4H), 7.20 - 7.16 (m, 4H), 6.10–6.08 (d, 2H), 5.57–5.53 (dd, 2H), 4.21–4.16 (m, 4H), 3.73–3.69 (m, 2H), 3.60–3.53 (m, 2H), 2.36–2.33 (m, 2H), 2.26–1.96 (m, 4H), 1.95–1.91 (d, 6H), 1.90–1.67 (m, 8H)

[0080] Example 9

[0081] Synthesis of High Refractive Index Resin Containing Sulfur Thiazoline

[0082] The route proposed in the present invention can also be used to synthesize high refractive index resins. The specific method is as follows: copolymerize diamino and bicyclic sulfur raw materials, cap the ends with epichlorohydrin sulfide, and then carry out ring closure with thiocarbonyl diimidazole and esterification reaction to obtain a high refractive index resin containing sulfur thiazoline. The following figure takes 9,9-bis(4-mercaptomethylphenyl)fluorene, ethylenediamine and epichlorohydrin sulfide as examples for illustration.

[0083]

[0084] From the above examples, it can be concluded that the compounds involved in the present invention can start from different primary amino-containing high refractive index raw materials (such as benzene ring, naphthalene ring, diphenyl sulfide, 9,9-bis(4-hydroxyphenyl)fluorene, etc.), and through ring-opening reaction of episulfide, ring closure with thiocarbonyl diimidazole and esterification reaction, a curable monomer with a high refractive index can be obtained.

[0085] Combined with the existing samples and the compounds in the above examples, the refractive index, room temperature state and compatibility test results with TPGDA are as follows:

[0086]

[0087]

[0088] From the above test results, it can be concluded that the sulfur-containing high refractive index curable monomers described in the present invention have refractive indices higher than those of the existing samples and are all above 1.6, and can be used in high refractive index environments. Compared with the existing compound samples, the compounds described in the present invention have good compatibility with the common photocurable monomer (TPGDA).

[0089] The above-described examples are only for describing the preferred embodiments of the present invention, and do not limit the concept and scope of the present invention. Without departing from the design concept of the present invention, various modifications and improvements made by those of ordinary skill in the art to the technical solutions of the present invention should fall within the protection scope of the present invention. The technical content claimed by the present invention has been fully recorded in the claims.

Claims

1. A sulfur-containing high-refractive-index curable monomer, Characterized in that: Having the chemical structure of formula I or formula II as follows: , Formula I Formula II Wherein the X 1 is one of acrylate or methacrylate structures, and the X in Formula I 2 is specifically one of the following chemical structures: X as described in Formula II 2 Specifically, it is one of the following chemical structures: 。 2. The sulfur-containing high-refractive-index curable monomer according to claim 1, Characterized in that: In the formulas I and II described above are replaced by through

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