Method for researching assembly rule of organic silicon dioxide polymer

Abstract

The invention discloses a method for researching an assembly rule of an organic silicon dioxide polymer. The method mainly comprises the following steps: (1) synthesizing an organic hybrid silsesquioxane ligand polymerized by Si-O bonds; 2) heating and reacting a ligand, metal salt, low-boiling-point alcohol and alkali under a dry condition; and 3) enabling a filtrate obtained in the previous stepto grow a metal organic hybrid silicon dioxide single crystal under an anhydrous condition. Single crystal X-ray diffraction research finds that when the temperature is raised and the alkali concentration is increased, the electron donating group on the ligand can promote the increase of coordination oxygen of the organic hybrid silsesquioxane ligand; the increase of the coordination oxygen can further promote the formation of a large silica ring, but the simultaneous increase of the temperature and the alkali concentration or the increase of the coordination metal ions can reduce the coordination oxygen so as to promote the formation of a smaller silica ring element.

Description

technical field

[0001] The invention belongs to the technical field of crystalline materials, and relates to a method for preparing a metal-organic hybrid silicon dioxide single crystal, in particular to a method for studying the law of organic silicon dioxide polymer assembly. Background technique

[0002] Periodic Mesoporous Organosilicas (PMOs) are a new type of organic-inorganic hybrid mesoporous materials obtained from organosilicon precursors under the action of structure-directing agents. The advantages of chemical stability, simple and diverse synthetic methods, and easy functionalization have aroused extensive research interest in recent years. Compared with traditional mesoporous silica materials, the organic groups in the framework endow PMOs with stronger hydrophobicity, thus, the PMOs framework is more stable in acidic and alkaline aqueous solutions. Due to the diversity of organic synthesis methods, people can use organic chemical reactions to provide abundant...

Examples

Embodiment 1

[0031] This embodiment relates to the preparation method of single crystal compound 1, which comprises the following steps:

[0032] Organic hybrid silsesquioxane ligand (0.0083 mol), potassium hydroxide solid (KOH) solid (0.0072 mol), n-butanol (20 mL) at a certain temperature to obtain a clear solution, copper chloride (0.0042 mol) A solution of n-butanol (10 mL) was added dropwise to the clear solution, 140 o Back distillation under the condition of C, cool to room temperature in a dry environment of phosphorus pentoxide, filter, collect the filtrate and put it in a desiccator equipped with phosphorus pentoxide-free, stand still, and precipitate 1 crystal. Single crystal diffraction analysis shows that compound 1 is a monoclinic crystal system, P21 / a space group. figure 1 It is the structural diagram of compound 1. The simplest phenylsiloxy element is connected by Si-O bond to form an open five-membered ring, and the two open five-membered rings with up and down symmetry...

Embodiment 2

[0034] This example relates to the preparation method of single crystal 2. The difference between this method and Example 1 is that the molar amount of potassium hydroxide is 0.0102 mol. same temperature (140 o C) Increase the concentration of base (0.0102 mol) to obtain compound 2 ( figure 2 ) is an orthorhombic tetragonal crystal system, P43 space group. Compound 2 has two independent siloxane rings that are completely different from 1. The up-and-down symmetrical six-membered siloxane ring and the hexanuclear metal ring are connected by silicon-oxygen bonds to form a sandwich cage structure.

Embodiment 3

[0036] This embodiment relates to the preparation method of single crystal 3, and the difference between this method and embodiment 1 is that the back distillation temperature is 120 o C, the molar mass of potassium hydroxide is 0.0074 mol. Single crystal diffraction analysis showed that the compound was monoclinic, P21 / n space group. The phenyl siloxanes are connected by silicon-oxygen bonds to form an open six-membered siloxane ring, and the upper and lower symmetrical open six-membered siloxane rings are connected by two phenyl siloxanes to form a fourteen-membered siloxane ring. Fourteen-membered siloxane rings are connected with copper ions and potassium ions through siloxane chains to form a large metallosiloxane cluster encapsulating chloride ions. Interestingly, the chloride ion is not in the center of the cage, and the chloride ion is close to Cu1 and Cu2, the distance between Cu1...Cl1 is 2.475 Å, and the distance between Cu2...Cl1 is 2.681 Å. At the same time, d...

technical field

[0001] The invention belongs to the technical field of crystalline materials, and relates to a method for preparing a metal-organic hybrid silicon dioxide single crystal, in particular to a method for studying the law of organic silicon dioxide polymer assembly. Background technique

[0002] Periodic Mesoporous Organosilicas (PMOs) are a new type of organic-inorganic hybrid mesoporous materials obtained from organosilicon precursors under the action of structure-directing agents. The advantages of chemical stability, simple and diverse synthetic methods, and easy functionalization have aroused extensive research interest in recent years. Compared with traditional mesoporous silica materials, the organic groups in the framework endow PMOs with stronger hydrophobicity, thus, the PMOs framework is more stable in acidic and alkaline aqueous solutions. Due to the diversity of organic synthesis methods, people can use organic chemical reactions to provide abundant...

Examples

Embodiment 1

[0031] This embodiment relates to the preparation method of single crystal compound 1, which comprises the following steps:

[0032] Organic hybrid silsesquioxane ligand (0.0083 mol), potassium hydroxide solid (KOH) solid (0.0072 mol), n-butanol (20 mL) at a certain temperature to obtain a clear solution, copper chloride (0.0042 mol) A solution of n-butanol (10 mL) was added dropwise to the clear solution, 140 o Back distillation under the condition of C, cool to room temperature in a dry environment of phosphorus pentoxide, filter, collect the filtrate and put it in a desiccator equipped with phosphorus pentoxide-free, stand still, and precipitate 1 crystal. Single crystal diffraction analysis shows that compound 1 is a monoclinic crystal system, P21 / a space group. figure 1 It is the structural diagram of compound 1. The simplest phenylsiloxy element is connected by Si-O bond to form an open five-membered ring, and the two open five-membered rings with up and down symmetry...

Embodiment 2

[0034] This example relates to the preparation method of single crystal 2. The difference between this method and Example 1 is that the molar amount of potassium hydroxide is 0.0102 mol. same temperature (140 o C) Increase the concentration of base (0.0102 mol) to obtain compound 2 ( figure 2 ) is an orthorhombic tetragonal crystal system, P43 space group. Compound 2 has two independent siloxane rings that are completely different from 1. The up-and-down symmetrical six-membered siloxane ring and the hexanuclear metal ring are connected by silicon-oxygen bonds to form a sandwich cage structure.

Embodiment 3

[0036] This embodiment relates to the preparation method of single crystal 3, and the difference between this method and embodiment 1 is that the back distillation temperature is 120 o C, the molar mass of potassium hydroxide is 0.0074 mol. Single crystal diffraction analysis showed that the compound was monoclinic, P21 / n space group. The phenyl siloxanes are connected by silicon-oxygen bonds to form an open six-membered siloxane ring, and the upper and lower symmetrical open six-membered siloxane rings are connected by two phenyl siloxanes to form a fourteen-membered siloxane ring. Fourteen-membered siloxane rings are connected with copper ions and potassium ions through siloxane chains to form a large metallosiloxane cluster encapsulating chloride ions. Interestingly, the chloride ion is not in the center of the cage, and the chloride ion is close to Cu1 and Cu2, the distance between Cu1...Cl1 is 2.475 Å, and the distance between Cu2...Cl1 is 2.681 Å. At the same time, d...

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