Series of 2-aminopyrazinyl salt birefringent optical crystals as well as preparation method and application thereof

Abstract

The invention relates to a series of 2-aminopyrazinyl salt birefringent optical crystals as well as a preparation method and application thereof. The series of 2-aminopyrazinyl salts are 2-aminopyrazinyl succinate, 2-aminopyrazinyl methyl sulfonate and 2-aminopyrazinyl sulfamate, the chemical formula of the 2-aminopyrazinyl succinate is (C4H5N3) 2 (C4H6O4), and the molecular weight is 308.31; the chemical formula of the 2-aminopyrazine methyl sulfonate is (C4H6N3) (CH3SO3), and the molecular weight of the 2-aminopyrazine methyl sulfonate is 191.21; the chemical formula of the 2-aminopyrazine sulfamate is (C4H6N3) (NH2SO3), the molecular weight is 192.20, the crystal is prepared by adopting a room-temperature solution method, the preparation process is simple and easy to operate, and the 2-aminopyrazine sulfamate shows excellent optical properties including large birefringence, wider transmission range and larger band gap, and can be used as an ultraviolet birefringence optical crystal with excellent properties.

Description

Technical Field

[0001] The invention relates to a series of 2-aminopyrazinyl salt birefringent optical crystals and a preparation method and application thereof. Background Art

[0002] Birefringent crystals are used to make prism polarizers, phase compensators, photoelectric modulators and beam isolators because of their ability to modulate and detect the polarization state of light. They are widely used in modern optical fields such as laser polarization technology, optical communications and scientific research. Currently, the main commercial birefringent crystals are CaCO3, YVO4, TiO2, MgF2, LiNbO3 and α-BaB2O4 crystals. However, with the increasing demand for miniaturization of modern optics, traditional inorganic birefringent crystals are difficult to meet the development needs of modern optical instruments. Therefore, the preparation of new ultraviolet birefringent crystals with large birefringence has important practical significance and application value.

[0003] MgF2 crystals have stable physical and chemical properties and high temperature thermal stability, and have very excellent transmission range and transmittance, but the birefringence of magnesium fluoride is only 0.012@546nm, and the small birefringence seriously limits its application range. CaCO3 crystals have high birefringence and short UV cutoff edges, but naturally formed calcite crystals have cleavage planes and are difficult to process. TiO2 crystals have a large birefringence, but their own hardness is high, which makes them difficult to cut. LiNbO3 has a relatively moderate birefringence, and it is easy to grow large-sized high-quality crystals with stable mechanical and physicochemical properties. α-BaB2O4 not only has a large birefringence, but also has a very high transmittance in the ultraviolet region, and has good physical and chemical stability. It is a UV birefringent crystal material with superior performance. However, the birefringence of these crystals is mostly less than 0.3, which is difficult to meet the diverse needs of modern optical instruments. Therefore, it is of great significance to explore new large birefringent crystals with simple preparation processes. Summary of the invention

[0004] The present invention aims to solve the above problems and provide a series of 2-aminopyrazinyl salt birefringent optical crystals and preparation methods and uses thereof. The series of 2-aminopyrazinyl salts are 2-aminopyrazine succinate, 2-aminopyrazine methylsulfonate and 2-aminopyrazine aminosulfonate. The crystals are prepared by a room temperature solution method. The preparation process is simple and easy to operate. The crystals exhibit excellent optical properties, including a large birefringence index and a wide transmission range. The crystals can be used as a class of ultraviolet birefringent optical crystals with excellent performance.

[0005] The present invention discloses a series of 2-aminopyrazine salt birefringent optical crystals, wherein the series of 2-aminopyrazine salts are 2-aminopyrazine succinate, 2-aminopyrazine methylsulfonate and 2-aminopyrazine aminosulfonate, wherein the chemical formula of 2-aminopyrazine succinate is (C4H5N3)2(C4H6O4), the molecular weight is 308.31, it belongs to the monoclinic system, the space group is P21 / c, and the unit cell parameters are β=104.630(5); 2-aminopyrazine methanesulfonate has the chemical formula (C4H6N3)(CH3SO3), molecular weight 191.21, belongs to the monoclinic system, space group is P21 / c, unit cell parameters are β=93.922(5); 2-aminopyrazine sulfamate has the chemical formula (C4H6N3)(NH2SO3), molecular weight 192.20, belongs to the monoclinic system, space group is C2 / c, unit cell parameters are β=101.254(3).

[0006] The preparation method of the series of 2-aminopyrazinyl salt birefringent optical crystals is prepared by a room temperature solution method:

[0007] The room temperature solution method for growing 2-aminopyrazinyl salt birefringent optical crystals is specifically performed in the following steps:

[0008] a. Weigh the synthetic raw materials of 2-aminopyrazinyl salt (C4H5N3) and (C4H6O4); (C4H5N3) and (CH3SO3H); (C4H5N3) and (NH2SO3H) in a molar ratio of 1:1, put them into a polytetrafluoroethylene beaker respectively, mix them evenly, add a mixed solution of ethanol and water or anhydrous ethanol in a volume ratio of 1:1-1:10, stir and mix evenly to obtain a mixed solution;

[0009] b. Filter the mixed solution in step a with qualitative filter paper, seal it with a polyvinyl chloride film, place it in a static environment without shaking, pollution and air convection, poke a number of small holes in the seal to adjust the volatilization rate of the solvent in the solution, let it stand at room temperature, and then gradually precipitate crystals in the solution. After the growth is completed, a 2-aminopyrazine succinate, 2-aminopyrazine methyl sulfonate or 2-aminopyrazine aminosulfonate birefringent optical crystal with a size of millimeter level is obtained.

[0010] The series of 2-aminopyrazinyl salt birefringent optical crystals are used in preparing optical isolators, polarization optical devices or electro-optical modulators.

[0011] The present invention discloses a series of 2-aminopyrazine salt birefringent optical crystals, a preparation method and a use thereof. The ultraviolet cutoff edges of 2-aminopyrazine succinate (C4H5N3)2 (C4H6O4), 2-aminopyrazine methylsulfonate (C4H6N3) (CH3SO3) and 2-aminopyrazine aminosulfonate (C4H6N3) (NH2SO3) in the crystals are 364nm, 360nm and 350nm respectively.

[0012] At a wavelength of 546 nm, the theoretically calculated birefringence of 2-aminopyrazine succinate (C4H5N3)2(C4H6O4) is 0.658.

[0013] At a wavelength of 546 nm, the theoretically calculated birefringence of 2-aminopyrazine methanesulfonate (C4H6N3)(CH3SO3) is 0.594.

[0014] At a wavelength of 546 nm, the theoretically calculated birefringence of 2-aminopyrazinesulfamate (C4H6N3)(NH2SO3) is 0.453.

[0015] The present invention discloses a series of 2-aminopyrazine salt birefringent optical crystals, preparation methods and uses thereof. The 2-aminopyrazine salt contains 2-aminopyrazine C4H5N3 organic π conjugated units. This optically active group has the following advantages:

[0016] (1) The organic π-conjugated units have a large dipole moment and are arranged in an antiparallel manner, which helps to enhance the birefringence of the crystal;

[0017] (2) The π-conjugated unit has a tendency to produce a significant difference in optical anisotropy between the in-plane direction and the perpendicular direction;

[0018] (3) By extending the conjugated framework, the polarization anisotropy can be amplified, thereby increasing the birefringence;

[0019] (4) Organic ligands are rich in hydrogen bonding sites, and the directionality of hydrogen bonding promotes the assembly of birefringent active units into a hydrogen-bonded supramolecular framework. After calculation, the [C4H5N3] group has a large polarizability anisotropy (δ) and hyperpolarizability (|βmax|).

[0020] In addition, the interatomic bond lengths in the [C4H5N3] ring are longer than those in the [B3O6], [C3N3O3], and [C5H6ON] groups, indicating that the hybridization between the C 2p and N 2p orbitals in the [C4H5N3] unit is higher. The amino groups on its outer ring can form hydrogen bonds with anions, which is beneficial to the growth of crystals.

[0021] The beneficial effects of a series of 2-aminopyrazinyl salt birefringent optical crystals, preparation methods and uses of the present invention are as follows:

[0022] The present invention uses a series of 2-aminopyrazine salts as birefringent optical crystals. Such crystals are a new type of birefringent optical crystals, exhibiting excellent optical properties, having a large birefringence of 0.453-0.658@546nm and a wide transmission range, and can be used as a type of ultraviolet birefringent optical crystals with excellent performance.

[0023] The preparation process of the invention has simple reaction conditions, simple operation, easy crystal growth, high product purity and stable properties. The preparation of the 2-aminopyrazine compound in the invention only uses a simple aqueous solution, does not require heating, has low energy consumption, is economical and environmentally friendly. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is the ultraviolet cutoff edge of the crystal of the present invention after ultraviolet / visible / infrared diffuse reflection test, wherein a is (C4H5N3)2(C4H6O4), b is (C4H6N3)(CH3SO3), and c is (C4H6N3)(NH2SO3).

[0025] Figure 2 The theoretically calculated birefringence of the three crystals in the present invention, wherein a is (C4H5N3)2(C4H6O4), b is (C4H6N3)(CH3SO3), and c is (C4H6N3)(NH2SO3).

[0026] Figure 3 Schematic diagram of the wedge-shaped birefringent crystal polarization beam splitter made in the present invention. DETAILED DESCRIPTION

[0027] The technical scheme of the present invention will be further described in detail in conjunction with specific embodiments. It should be understood that the following embodiments are only exemplary descriptions and explanations of the present invention, and should not be construed as limiting the scope of protection of the present invention. All technologies implemented based on the above content of the present invention are included in the scope that the present invention is intended to protect.

[0028] Unless otherwise specified, the raw materials and reagents used in the following examples are commercially available or can be prepared by known methods.

[0029] Example 1

[0030] The room temperature solution method is used to grow 2-aminopyrazine succinate (C4H5N3)2 (C4H6O4) birefringent optical crystals, C4H5N3 (99%) and C4H6O4 (99%) are synthetic raw materials, and the specific operation is carried out according to the following steps:

[0031] a. Weigh C4H5N3 and C4H6O4 in a molar ratio of 1:1, put them into a polytetrafluoroethylene beaker and mix them evenly, add a mixture of ethanol and water in a volume ratio of 1:1, stir and mix evenly to obtain a mixed solution;

[0032] b. Filter the mixed solution in step a with qualitative filter paper, seal it with polyvinyl chloride film, place it in a static environment without shaking, pollution, or air convection, pierce several small holes in the seal to adjust the evaporation rate of the solvent in the solution, and let it stand at room temperature. Then, crystals gradually precipitate from the solution. When the growth is completed, a crystal with a size of 1.5×1.2×0.2mm is obtained. 3 2-Aminopyrazine succinate birefringent optical crystals.

[0033] Example 2

[0034] The room temperature solution method is used to grow 2-aminopyrazine succinate (C4H5N3)2 (C4H6O4) birefringent optical crystals, C4H5N3 (99%) and C4H6O4 (99%) are synthetic raw materials, and the specific operation is carried out according to the following steps:

[0035] a. Weigh C4H5N3 and C4H6O4 in a molar ratio of 1:1, put them into a polytetrafluoroethylene beaker and mix them evenly, add a mixed solution of ethanol and water in a volume ratio of 2:3, stir and mix evenly to obtain a mixed solution;

[0036] b. Filter the mixed solution in step a with qualitative filter paper, seal it with polyvinyl chloride film, place it in a static environment without shaking, pollution, or air convection, pierce several small holes in the seal to adjust the evaporation rate of the solvent in the solution, and let it stand at room temperature. Then, crystals gradually precipitate from the solution. When the growth is completed, a crystal with a size of 1.6×1.2×0.2mm is obtained. 3 2-Aminopyrazine succinate birefringent optical crystals.

[0037] Example 3

[0038] The room temperature solution method is used to grow 2-aminopyrazine succinate (C4H5N3)2 (C4H6O4) birefringent optical crystals, C4H5N3 (99%) and C4H6O4 (99%) are synthetic raw materials, and the specific operation is carried out according to the following steps:

[0039] a. Weigh C4H5N3 and C4H6O4 in a molar ratio of 1:1, put them into a polytetrafluoroethylene beaker and mix them evenly, add a mixture of ethanol and water in a volume ratio of 1:3, stir and mix evenly to obtain a mixed solution;

[0040] b. Filter the mixed solution in step a with qualitative filter paper, seal it with polyvinyl chloride film, place it in a static environment without shaking, pollution, or air convection, pierce several small holes in the seal to adjust the evaporation rate of the solvent in the solution, and let it stand at room temperature. Then, crystals gradually precipitate from the solution. When the growth is completed, a crystal with a size of 1.3×1.1×0.2mm is obtained. 3 2-Aminopyrazine succinate birefringent optical crystals.

[0041] Example 4

[0042] The room temperature solution method for growing 2-aminopyrazine methanesulfonate (C4H6N3) (CH3SO3) crystals: C4H5N3 (99%) and CH3SO3H (70%) are synthetic raw materials, and the specific operation is carried out according to the following steps:

[0043] a. Weigh C4H5N3 and CH3SO3H in a molar ratio of 1:1, put them into a polytetrafluoroethylene beaker and mix them evenly, add anhydrous ethanol, stir and mix evenly to obtain a mixed solution;

[0044] b. Filter the mixed solution in step a with qualitative filter paper, seal it with polyvinyl chloride film, place it in a static environment without shaking, pollution, and air convection, pierce several small holes in the seal to adjust the volatilization rate of the solvent in the solution, let it stand at room temperature, and then gradually precipitate crystals in the solution. When the growth is completed, a crystal with a size of 2.0×2.0×0.4mm is obtained. 3 2-Aminopyrazine methanesulfonate birefringent optical crystals.

[0045] Example 5

[0046] The room temperature solution method for growing 2-aminopyrazine sulfamate (C4H6N3) (NH2SO3) crystals: C4H5N3 (99%) and NH2SO3H (99%) are synthetic raw materials, and the specific operation is carried out according to the following steps:

[0047] a. Weigh C4H5N3 and NH2SO3H in a molar ratio of 1:1, put them into a polytetrafluoroethylene beaker and mix them evenly, add anhydrous ethanol, stir and mix evenly to obtain a mixed solution;

[0048] b. Filter the mixed solution in step a with qualitative filter paper, seal it with polyvinyl chloride film, place it in a static environment without shaking, pollution, or air convection, pierce several small holes in the seal to adjust the evaporation rate of the solvent in the solution, and let it stand at room temperature. Then, crystals gradually precipitate from the solution. When the growth is completed, a crystal with a size of 7.0×5.5×4.1 mm is obtained. 3 2-Aminopyrazinesulfamate birefringent optical crystals.

[0049] Example 6

[0050] Taking the 2-aminopyrazine aminosulfonate (C4H6N3) (NH2SO3) birefringent crystal in Example 5 as an example, a polarization beam splitter is prepared:

[0051] The 2-aminopyrazine aminosulfonate birefringent crystal is used to prepare a wedge-shaped birefringent crystal polarization beam splitter (such as Figure 3 As shown in the figure, a wedge-shaped birefringent crystal, after a beam of natural light is incident along the optical axis direction, it can be separated into two beams of linearly polarized light (o light 2 and e light 3) after passing through the crystal, thus realizing the separation of the light beams.

Claims

1. A series of 2-aminopyrazinyl salt birefringent optical crystals, characterized in that The series of 2-aminopyrazine salts are 2-aminopyrazine succinate, 2-aminopyrazine methylsulfonate and 2-aminopyrazine aminosulfonate, wherein the chemical formula of 2-aminopyrazine succinate is (C4H5N3)2(C4H6O4), the molecular weight is 308.31, it belongs to the monoclinic system, and the space group is P twenty one / c , the unit cell parameters are a=5.3958(6) Å, b=19.471(2) Å, c=6.9453(7) Å, β=104.630(5); the chemical formula of 2-aminopyrazine methanesulfonate is (C4H6N3)(CH3SO3), the molecular weight is 191.21, it belongs to the monoclinic system, and the space group is P twenty one / c , the unit cell parameters are a=5.1632(8) Å, b=10.2883(17) Å, c=15.253(3) Å, β=93.922(5); the chemical formula of 2-aminopyrazine aminosulfonate is (C4H6N3)(NH2SO3), the molecular weight is 192.20, it belongs to the monoclinic system, and the space group is C 2 / c The unit cell parameters are a=23.329(2) Å, b=8.9732(6) Å, c=7.4927(6) Å, β=101.254(3).

2. The method for preparing a series of 2-aminopyrazinyl salt birefringent optical crystals according to claim 1, characterized in that Made by room temperature solution method: The room temperature solution method for growing 2-aminopyrazinyl salt birefringent optical crystals is specifically performed in the following steps: a. Weigh the synthetic raw materials of 2-aminopyrazinyl salt (C4H5N3) and (C4H6O4); (C4H5N3) and (CH3SO3H); (C4H5N3) and (NH2SO3H) in a molar ratio of 1:1, put them into a polytetrafluoroethylene beaker respectively, mix them evenly, add a mixed solution of ethanol and water or anhydrous ethanol in a volume ratio of 1:1-1:10, stir and mix evenly to obtain a mixed solution; b. Filter the mixed solution in step a with qualitative filter paper, seal it with a polyvinyl chloride film, place it in a static environment without shaking, pollution and air convection, poke a number of small holes in the seal to adjust the volatilization rate of the solvent in the solution, let it stand at room temperature, and then gradually precipitate crystals in the solution. After the growth is completed, a 2-aminopyrazine succinate, 2-aminopyrazine methyl sulfonate or 2-aminopyrazine aminosulfonate birefringent optical crystal with a size of millimeter level is obtained.

3. Use of the series of 2-aminopyrazinyl salt birefringent optical crystals according to claim 1 in the preparation of optical isolators, polarization beam splitters or electro-optical modulators.

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