CN114316277A - Solid phosphazene compound, preparation method and application - Google Patents

Abstract

The invention relates to a solid phosphazene compound which has a structure shown in a formula (1):

wherein R is_aIs a crosslinking agent, R_bis-N ═ PR₃Or is

R₁、R₂、R₃、R₄Each independently selected from H, C_1‑6Alkyl radical, C_1‑6Cycloalkyl radical, C_1‑6Heterocycloalkyl, optionally substituted aryl, optionally substituted benzyl. TheThe compound has a plurality of guanidyl functional groups, can be used as a catalyst, can greatly reduce the technological process of separating and purifying the catalyst from the product, can be recovered only by simple filtration, can realize recycling after recovery, and has little change in catalytic activity after recovery.

Description

Solid phosphazene compound, preparation method and application

Technical Field

The invention relates to the technical field of organic chemistry, in particular to a solid phosphazene compound, a preparation method and application thereof.

Background

The information in this background section is only for enhancement of understanding of the general background of the invention and is not necessarily to be construed as an admission or any form of suggestion that this information forms the prior art that is already known to a person of ordinary skill in the art.

Phosphazene compounds are widely applied to the field of organic catalysis, although the phosphazene compounds are researched for many years till now, the applicable types of the phosphazene compounds are still few, especially most of the phosphazene compounds are liquid phase, the post-treatment steps required after the phosphazene compounds are used are complex, and the catalytic activity is obviously reduced after the phosphazene compounds are recovered.

Therefore, the research on the application of the phosphazene compound which can simplify the process flow and can still keep good catalytic activity after being recovered as the catalyst has important significance.

Disclosure of Invention

In order to overcome the problems, the invention designs a solid phosphazene compound which has a plurality of guanidyl functional groups and can be used as a catalyst, thereby greatly reducing the process flow of separating and purifying the catalyst from a product, being capable of being recovered only by simple filtration, realizing recycling after recovery and having little change of catalytic activity after recovery.

Based on the research results, the present disclosure provides the following technical solutions:

in a first aspect of the present disclosure, a solid phosphazene compound is provided, which has a structure shown in formula (1):

wherein R is_aIs a crosslinking agent, R_bis-N ═ PR₃Or is

R₁、R₂、R₃、R₄Each independently is H, C_1-6Alkyl radical, C_1-6Cycloalkyl radical, C_1-6Heterocycloalkyl, optionally substituted aryl, optionally substituted benzyl.

In a second aspect of the present invention, a preparation method of the solid phosphazene compound is provided, which includes:

contacting phosphorus pentachloride with a compound shown as a formula (2), then contacting with ammonia gas, and finally contacting with an alkali solution to obtain a compound shown as a formula (3);

HN＝PR₃

formula (3);

II, contacting hexachlorocyclotriphosphazene with a cross-linking agent and an acid-binding agent to obtain a compound shown as a formula (4);

and III, carrying out contact reaction on the compound in the formula (3) and the compound in the formula (4) and an acid-binding agent to prepare the compound in the formula (1).

In a third aspect of the present invention, an application of the solid phosphazene compound in an organic catalytic reaction is provided, and preferably, the organic reaction is Knoevenagel reaction or Aldol reaction.

One or more embodiments of the invention achieve at least the following technical effects:

(1) on one hand, the solid phosphazene catalyst is simpler and more convenient in post-treatment; on the other hand, the recycling can be realized. The post-treatment is simple and convenient, and the catalyst is only required to be filtered after the reaction is finished, so that the process flow of separating and purifying the soluble catalyst from the product is avoided; the characteristic of recycling enables the same batch of catalyst to be used for multiple times, the catalytic activity is basically not affected, the waste of the catalyst and the pollution problem caused by separation and purification of the catalyst are reduced, and the method has great cost advantage and environmental protection advantage.

(2) The solid phosphazene catalyst has the advantages of simple preparation process and low raw material cost, and part of solvent can be recycled, thereby greatly reducing the influence on the environment.

Drawings

The accompanying drawings, which are included to provide a further understanding of the disclosure, illustrate embodiments of the disclosure and together with the description serve to explain the disclosure and are not to limit the disclosure.

FIG. 1 is a nuclear magnetic resonance hydrogen spectrum of a product obtained in example 2 of the present invention;

FIG. 2 is a mass spectrum of the product obtained in example 2 of the present invention;

FIG. 3 is an SEM photograph of a product obtained in example 3 of the present invention;

FIG. 4 is a NMR chart of a product obtained in example 4 of the present invention;

FIG. 5 is a NMR chart of a product obtained in example 6 of the present invention;

FIG. 6 is a NMR chart of a product obtained in example 7 of the present invention;

FIG. 7 is a NMR chart of a product obtained in example 8 of the present invention.

Detailed Description

It should be noted that the following detailed description is exemplary and is intended to provide further explanation of the disclosure. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs.

It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments according to the present disclosure. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, and it should be understood that when the terms "comprises" and/or "comprising" are used in this specification, they specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof, unless the context clearly indicates otherwise.

As described in the background art, the existing phosphazenes have complicated post-treatment steps and the catalytic activity is remarkably reduced after recovery. Therefore, the present disclosure provides a solid phosphazene compound, which can simplify the post-treatment step and improve the catalytic activity after recovery.

In a first aspect of the present disclosure, a solid phosphazene compound is provided, which has a structure shown in formula (1):

wherein R is_aIs a crosslinking agent, R_bis-N ═ PR₃Or is

R₁、R₂、R₃、R₄Each independently is H, C_1-6Alkyl radical, C_1-6Cycloalkyl radical, C_1-6Heterocycloalkyl, optionally substituted aryl, optionally substituted benzyl.

In a second aspect of the present invention, a preparation method of the solid phosphazene compound is provided, which includes:

contacting phosphorus pentachloride with a compound shown as a formula (2), then contacting with ammonia gas, and finally contacting with an alkali solution to obtain a compound shown as a formula (3);

HN＝PR₃

formula (3);

II, contacting hexachlorocyclotriphosphazene with a cross-linking agent and an acid-binding agent to obtain a compound shown as a formula (4);

and III, carrying out contact reaction on the compound in the formula (3) and the compound in the formula (4) and an acid-binding agent to prepare the compound in the formula (1).

In a typical embodiment, in step i, the contacting is performed in an anhydrous organic solvent, and further, the anhydrous organic solvent is at least one selected from dichloromethane, acetonitrile, toluene, tetrahydrofuran, and preferably dichloromethane.

In one exemplary embodiment, in step i, the contacting is carried out under a protective gas atmosphere; further, the shielding gas is selected from one of argon, nitrogen, helium, carbon dioxide and carbon monoxide, and is preferably argon.

In a typical embodiment, in step I, the compound represented by the formula (2) is contacted with ammonia gas under the following conditions: reacting for 1515 hours at-5555 ℃; further, the contact time with the alkali solution was 15515 hours.

In a typical embodiment, in step i, the base is selected from one of aqueous sodium hydroxide solution, aqueous potassium hydroxide solution, aqueous sodium carbonate solution, aqueous sodium bicarbonate solution, aqueous potassium carbonate solution, aqueous potassium bicarbonate solution, and aqueous ammonia, preferably aqueous sodium hydroxide solution; further, the solubility of the alkali solution is 5.551.5mol L-¹。

In a typical embodiment, in step i, the mass ratio of the phosphorus pentachloride to the compound represented by formula (2) is: 1: (1.5-3).

In a typical embodiment, in step I, no significant surface precipitation occurs after the introduction of ammonia gas until stirring is stopped.

In one exemplary embodiment, in step ii, the contacting is carried out in an organic solvent; further, the organic solvent is one selected from acetonitrile, ethanol, toluene, dimethyl sulfoxide, N' -dimethylformamide, tetrahydrofuran and dichloromethane, and preferably acetonitrile.

In one exemplary embodiment, step ii, the contacting is performed under a protective gas atmosphere; further, the shielding gas is selected from one of argon, nitrogen, helium, carbon monoxide and carbon dioxide, and is preferably argon.

In a typical embodiment, the cross-linking agent is selected from one of 4,4 '-dihydroxydiphenyl sulfone, bisphenol a, hexafluorobisphenol a, hydroquinone, phenolphthalein, bisphenol fluorene, preferably 4, 4' -dihydroxydiphenyl sulfone.

In a typical embodiment, in step II, the molar ratio of the hexachlorocyclotriphosphazene to the crosslinking agent to the acid scavenger is 1 (152) to (254), preferably 1:1.5: 3.

In a typical embodiment, in step ii, the acid-binding agent is one selected from triethylamine, tetramethylguanidine, sodium bicarbonate, potassium bicarbonate, sodium hydroxide, potassium carbonate, sodium carbonate, potassium hydroxide, and ammonia, preferably triethylamine.

In a typical embodiment, the contact reaction is carried out by stirring, and further, the stirring includes electromagnetic stirring, mechanical stirring, ultrasonic oscillation, and preferably ultrasonic oscillation.

In a typical embodiment, in step II, the reaction temperature is 15555 ℃ and the reaction time is 255h, preferably 3 h.

In a typical embodiment, in step iii, the acid-binding agent is one selected from triethylamine, tetramethylguanidine, sodium carbonate, sodium bicarbonate, potassium carbonate, sodium hydroxide, potassium hydroxide, and ammonia, preferably triethylamine.

In one exemplary embodiment, step iii, the contacting is carried out in an organic solvent; further, the organic solvent is one selected from acetonitrile, toluene, dimethyl sulfoxide, N' -dimethylformamide, ethanol, tetrahydrofuran and dichloromethane, and preferably acetonitrile.

In a typical embodiment, in step III, the reaction temperature is 1555165 ℃ and the reaction time is 455135 h; preferably at 125 ℃ for 48 h.

In a typical embodiment, in step iii, the mass ratio of the compound of formula (4), triethylamine and the compound of formula (3) is: 1: (1-2): (2-3).

In a third aspect of the present invention, an application of the solid phosphazene compound in an organic catalytic reaction is provided, and preferably, the organic reaction is Knoevenagel reaction or Aldol reaction.

In a typical embodiment, the method of using the compound in Knoevenagel reaction comprises: contacting said compound with at least one aromatic aldehyde and ethyl cyanoacetate to obtain a Knoevenagel condensation reaction product;

further, the aromatic aldehyde is selected from one of 2-nitrobenzaldehyde, 3-nitrobenzaldehyde, 4-nitrobenzaldehyde, 2, 4-dichlorobenzaldehyde, 2, 6-dichlorobenzaldehyde, 2-chlorobenzaldehyde, 3-chlorobenzaldehyde, 4-chlorobenzaldehyde, 2-fluorobenzaldehyde, 3-fluorobenzaldehyde, 4-fluorobenzaldehyde, 2-hydroxybenzaldehyde and 2-aminobenzaldehyde.

Further, the molar ratio of the aromatic aldehyde to ethyl cyanoacetate is 1 (152), preferably 1: 1.1. Thereby, the yield of the product can be further improved.

Further, the contacting is carried out at 55135 ℃ for 158h, preferably 155 ℃ for 5 h. Thereby, the yield of the product can be further improved.

Further, the contact reaction is carried out in an organic solvent, wherein the solvent is one selected from water, ethanol, toluene, tetrahydrofuran, dimethyl sulfoxide, acetonitrile and dichloromethane, and ethanol is preferred.

The product prepared by the method does not contain metal elements, almost has no catalyst residue, and is simple and convenient in post-treatment and easy to purify.

In a typical embodiment, the method of application of the compound in the Aldol reaction comprises:

(ii) participating the catalyst in the reaction of at least one aldehyde with a ketone to obtain a product;

further, the aldehydes include, but are not limited to, 2-nitrobenzaldehyde, 3-nitrobenzaldehyde, 4-nitrobenzaldehyde, 2, 4-dichlorobenzaldehyde, 2, 6-dichlorobenzaldehyde, 2-chlorobenzaldehyde, 3-chlorobenzaldehyde, 4-chlorobenzaldehyde, 2-fluorobenzaldehyde, 3-fluorobenzaldehyde, 4-fluorobenzaldehyde, 2-hydroxybenzaldehyde, 2-aminobenzaldehyde, acetaldehyde, propionaldehyde, isobutyraldehyde, n-butyraldehyde.

Further, the ketones include acetone, cyclohexanone, butanone.

Further, the reaction is carried out in an organic solvent; further, the organic solvent is one selected from water, ethanol, acetonitrile, tetrahydrofuran, dichloromethane, dimethyl sulfoxide, N' -dimethylformamide and toluene, and preferably ethanol.

Further, the reaction conditions are as follows: the reaction is carried out at 555155 ℃ for 358h, preferably at 65 ℃ for 6h.

In order to make the technical solutions of the present disclosure more clearly understood by those skilled in the art, the technical solutions of the present disclosure will be described in detail below with reference to specific examples and comparative examples.

Example 1:

preparation of PZS microspheres

Dissolving 1.78g of hexachlorocyclotriphosphazene and 2.55g of triethylamine in 255ml of acetonitrile to obtain a solution A, dissolving 2.55g of 4, 4' -dihydroxy diphenyl sulfone in 255ml of acetonitrile to obtain a solution B, uniformly mixing, dropwise adding the solution B into the solution A under the ultrasonic condition, controlling the temperature of the system to be 35545 ℃, reacting for 3 hours after dropwise adding, filtering and separating out a solid phase after the reaction is finished, washing with absolute ethyl alcohol and deionized water for multiple times, drying at 65 ℃ in a vacuum oven, collecting 3.47g of a product, and obtaining the yield of 85.32%.

Example 2:

preparation of tris (tetramethylguanidine) phosphazene

25.824g of phosphorus pentachloride is dissolved in 55ml of anhydrous dichloromethane in a three-neck flask, the three-neck flask is placed in a cold bath at the temperature of-25 ℃ under the protection of argon, 51.75g of tetramethylguanidine is dripped into the system through a constant pressure funnel, and the reaction is carried out for 1h after the dripping is finished. And after the reaction is continued for 2 hours at room temperature, the temperature of the system is reduced to-25 ℃ again, and ammonia gas is continuously introduced into the system until the system is saturated. After the reaction is carried out for 1h, ammonia gas is continuously introduced at room temperature for reaction for 3h until no obvious precipitate is generated on the surface after the stirring is stopped. Filtering to remove a solid phase, performing rotary evaporation to remove the solvent, adding the obtained solid into 45ml of 55 wt% NaOH aqueous solution, mixing and stirring for 12h under the protection of argon, filtering to remove the solid phase, performing rotary evaporation to remove the solvent on the liquid phase, and drying the product in a vacuum drying oven at 55 ℃ for 24h to obtain 33.5g of light yellow liquid with the yield of 85.55%.

Example 3:

15.23g of tris (tetramethylguanidine) phosphazene is dissolved in 255ml of acetonitrile in a flask, after complete dissolution, 3.97g of PZS microspheres prepared in example 1 and 5.52g of triethylamine are added, reaction is carried out at 125 ℃ under the protection of argon for 48h, after the reaction is finished, a solid phase is separated by filtration, washed three times by absolute ethyl alcohol, and dried in a vacuum oven at 65 ℃ to obtain 4.65g of product. The SEM spectrogram of the obtained product is shown in FIG. 3, and it can be seen that the obtained product has regular morphology.

Example 4:

dissolving 5.74g of 2, 4-dichlorobenzaldehyde and 5.63g of ethyl cyanoacetate in 15ml of absolute ethanol, adding 5.13g of catalyst, reacting at 155 ℃ for 5 hours, directly adding ethyl acetate to dissolve the product, filtering to separate out the catalyst, removing ethyl acetate and ethanol by rotary evaporation to obtain a solid crude product, completely dissolving the solid with 25ml of ethanol at 55 ℃, putting the solid into a refrigerator for refrigeration crystallization, separating out colorless crystals, filtering to collect the product, putting the product into a vacuum oven for drying at 45 ℃, collecting 1.17g of the product, and obtaining the yield of 91.45%.

Example 5:

dissolving 5.87g of 2, 6-dichlorobenzaldehyde and 5.63g of ethyl cyanoacetate in 15ml of absolute ethanol, adding 5.15g of catalyst, reacting at 155 ℃ for 5 hours, directly adding ethyl acetate to dissolve the product after the reaction is finished, filtering to separate out the catalyst, removing ethyl acetate and ethanol by rotary evaporation to obtain a solid crude product, completely dissolving the solid with 25ml of ethanol at 55 ℃, crystallizing at 258 ℃ at low temperature, separating out colorless crystals, filtering to collect the product, drying at 45 ℃ in a vacuum oven, collecting 1.16g of the product, and obtaining the yield of 81.25%.

Example 6:

dissolving 5.76g of o-nitrobenzaldehyde and 5.63g of ethyl cyanoacetate in 15ml of absolute ethanol, adding 5.15g of catalyst, reacting for 5 hours at 155 ℃, directly adding ethyl acetate to dissolve the product after the reaction is finished, filtering and separating out the catalyst, removing ethyl acetate and ethanol by rotary evaporation to obtain a solid crude product, completely dissolving the solid with 25ml of ethanol at 55 ℃, crystallizing at 258 ℃ at low temperature, separating out colorless crystals, filtering and collecting the product, drying at 45 ℃ in a vacuum oven, collecting 1.35g of the product, and obtaining the yield of 98.55%.

Example 7:

dissolving m-nitrobenzaldehyde (5.77g, 5mmol) and ethyl cyanoacetate (5.63g, 5.5mmol) in 15ml of absolute ethanol, adding the catalyst prepared in example 3, reacting for 5h at 155 ℃, directly adding ethyl acetate to dissolve the product after the reaction is finished, filtering and separating out the catalyst, removing ethyl acetate and ethanol by rotary evaporation to obtain a solid crude product, completely dissolving the solid with 25ml of ethanol at 55 ℃, crystallizing at 258 ℃ at low temperature, filtering and collecting the product, drying at 45 ℃ in a vacuum oven, collecting 1.18g of the product, and obtaining the yield of 88.56%.

Example 8:

dissolving m-nitrobenzaldehyde (5.77g, 5mmol) and ethyl cyanoacetate (5.63g, 5.5mmol) in 15ml of absolute ethanol, adding the catalyst prepared in example 3, reacting for 5 hours at 5 ℃, directly adding ethyl acetate to dissolve the product after the reaction is finished, filtering and separating out the catalyst, removing ethyl acetate and ethanol by rotary evaporation to obtain a solid crude product, completely dissolving the solid with 25ml of ethanol at 55 ℃, crystallizing at 258 ℃ at low temperature, filtering and collecting the product, drying at 45 ℃ in a vacuum oven, collecting 1.55g of the product, and obtaining the yield of 85.15%.

Example 9:

dissolving m-nitrobenzaldehyde (5.77g, 5mmol) and ethyl cyanoacetate (5.63g, 5.5mmol) in 15ml of absolute ethanol, adding the catalyst prepared in example 3, reacting for 5h at 25 ℃, directly adding ethyl acetate to dissolve the product after the reaction is finished, filtering and separating out the catalyst, removing ethyl acetate and ethanol by rotary evaporation to obtain a solid crude product, completely dissolving the solid with 25ml of ethanol at 55 ℃, crystallizing at 258 ℃ at low temperature, filtering and collecting the product, drying at 45 ℃ in a vacuum oven, collecting 1.16g of the product, and obtaining the yield of 87.22%.

Example 10:

dissolving p-nitrobenzaldehyde (5.79g, 5mmol) and ethyl cyanoacetate (5.63g, 5.5mmol) in 15ml of absolute ethanol, adding the catalyst prepared in example 3, reacting for 5h at 155 ℃, directly adding ethyl acetate to dissolve the product after the reaction is finished, filtering and separating out the catalyst, removing ethyl acetate and ethanol by rotary evaporation to obtain a solid crude product, completely dissolving the solid with 25ml of ethanol at 55 ℃, crystallizing at 258 ℃ at low temperature, filtering and collecting the product, drying at 45 ℃ in a vacuum oven, collecting 1.17g of the product, and obtaining the yield of 84.78%.

Example 11:

dissolving m-nitrobenzaldehyde (5.76g, 5mmol) and ethyl cyanoacetate (5.63g, 5.5mmol) in 15ml of absolute ethanol, adding the catalyst (A) prepared in example 3, reacting for 5h at 155 ℃, directly adding ethyl acetate to dissolve the product after the reaction is finished, filtering and separating out the catalyst, removing ethyl acetate and ethanol by rotary evaporation to obtain a solid crude product, completely dissolving the solid with 25ml of ethanol at 55 ℃, crystallizing at 258 ℃ at low temperature, separating out colorless crystals, filtering and collecting the product, drying at 45 ℃ in a vacuum oven, calculating the yield, washing the recovered catalyst with ethanol for a plurality of times, and drying in vacuum at 45 ℃ to obtain the catalyst A-1.

Dissolving m-nitrobenzaldehyde (5.76g, 5mmol) and ethyl cyanoacetate (5.63g, 5.5mmol) in 15ml of absolute ethanol, adding a catalyst A-1, reacting at 155 ℃ for 5h, directly adding ethyl acetate to dissolve a product after the reaction is finished, filtering and separating out the catalyst, removing ethyl acetate and ethanol by rotary evaporation to obtain a solid crude product, completely dissolving the solid with 25ml of ethanol at 55 ℃, crystallizing at 258 ℃ at low temperature, separating out colorless crystals, filtering and collecting the product, drying at 45 ℃ in a vacuum oven, calculating the yield, washing the recovered catalyst with ethanol for several times, and drying in vacuum at 45 ℃ to obtain the catalyst A-2.

Dissolving m-nitrobenzaldehyde (5.76g, 5mmol) and ethyl cyanoacetate (5.63g, 5.5mmol) in 15ml of absolute ethanol, adding a catalyst A-2, reacting at 155 ℃ for 5h, directly adding ethyl acetate to dissolve a product after the reaction is finished, filtering and separating out the catalyst, removing ethyl acetate and ethanol by rotary evaporation to obtain a solid crude product, completely dissolving the solid with 25ml of ethanol at 55 ℃, crystallizing at 258 ℃ at low temperature, separating out colorless crystals, filtering and collecting the product, drying at 45 ℃ in a vacuum oven, calculating the yield, washing the recovered catalyst with ethanol for several times, and drying in vacuum at 45 ℃ to obtain the catalyst A-3.

Dissolving m-nitrobenzaldehyde (5.76g, 5mmol) and ethyl cyanoacetate (5.63g, 5.5mmol) in 15ml of absolute ethanol, adding a catalyst A-3, reacting at 155 ℃ for 5h, directly adding ethyl acetate to dissolve a product after the reaction is finished, filtering and separating out the catalyst, removing ethyl acetate and ethanol by rotary evaporation to obtain a solid crude product, completely dissolving the solid with 25ml of ethanol at 55 ℃, crystallizing at 258 ℃ at low temperature, separating out colorless crystals, filtering and collecting the product, drying at 45 ℃ in a vacuum oven, calculating the yield, washing the recovered catalyst with ethanol for several times, and drying in vacuum at 45 ℃ to obtain the catalyst A-4.

Dissolving m-nitrobenzaldehyde (5.76g, 5mmol) and ethyl cyanoacetate (5.63g, 5.5mmol) in 15ml of absolute ethanol, adding a catalyst A-4, reacting at 155 ℃ for 5h, directly adding ethyl acetate to dissolve a product after the reaction is finished, filtering and separating out the catalyst, removing ethyl acetate and ethanol by rotary evaporation to obtain a solid crude product, completely dissolving the solid with 25ml of ethanol at 55 ℃, crystallizing at 258 ℃ at low temperature, separating out colorless crystals, filtering and collecting the product, drying at 45 ℃ in a vacuum oven, calculating the yield, washing the recovered catalyst with ethanol for several times, and drying in vacuum at 45 ℃ to obtain the catalyst A-5.

Dissolving m-nitrobenzaldehyde (5.76g, 5mmol) and ethyl cyanoacetate (5.63g, 5.5mmol) in 15ml of absolute ethanol, adding a catalyst A-5, reacting at 155 ℃ for 5h, directly adding ethyl acetate to dissolve a product after the reaction is finished, filtering and separating out the catalyst, removing ethyl acetate and ethanol by rotary evaporation to obtain a solid crude product, completely dissolving the solid with 25ml of ethanol at 55 ℃, crystallizing at 258 ℃ at low temperature, separating out colorless crystals, filtering and collecting the product, drying at 45 ℃ in a vacuum oven, calculating the yield, washing the recovered catalyst with ethanol for several times, and drying in vacuum at 45 ℃ to obtain the catalyst A-6.

The results of the catalyst recovery cycle testing are shown in table 1.

TABLE 1 test results for catalyst recovery cycle

Catalyst and process for preparing same	Number of times of use	Yield of
			A	1	91.45％
A-1
		2	95.35％
A-2				3	92.64％
	A-3	4	84.55％
A-4
		5	95.15％
A-5
		6	88.89％

Example 12:

dissolving 2, 4-dichlorobenzaldehyde (5.87g, 5mmol) and ethyl cyanoacetate (5.63g, 5.5mmol) in 15ml of absolute ethanol, adding the catalyst (B) prepared in example 3, reacting at 155 ℃ for 5h, directly adding ethyl acetate to dissolve the product, filtering to separate the catalyst, performing rotary evaporation to remove ethyl acetate and ethanol to obtain a solid crude product, completely dissolving the solid with 25ml of ethanol at 55 ℃, crystallizing at 258 ℃ at low temperature, separating colorless crystals, filtering to collect the product, drying at 45 ℃ in a vacuum oven, calculating the yield, washing the recovered catalyst with ethanol for several times, and drying in vacuum at 45 ℃ to obtain the catalyst B-1.

Dissolving 2, 4-dichlorobenzaldehyde (5.87g, 5mmol) and ethyl cyanoacetate (5.63g, 5.5mmol) in 15ml of absolute ethanol, adding a catalyst B-1, reacting at 155 ℃ for 5h, directly adding ethyl acetate to dissolve a product, filtering to separate out the catalyst, performing rotary evaporation to remove ethyl acetate and ethanol to obtain a solid crude product, completely dissolving the solid with 25ml of ethanol at 55 ℃, crystallizing at 258 ℃ at low temperature, separating out colorless crystals, filtering to collect the product, drying at 45 ℃ in a vacuum oven, calculating the yield, washing the recovered catalyst with ethanol for several times, and drying in vacuum at 45 ℃ to obtain the catalyst B-2.

Dissolving 2, 4-dichlorobenzaldehyde (5.87g, 5mmol) and ethyl cyanoacetate (5.63g, 5.5mmol) in 15ml of absolute ethanol, adding a catalyst B-2, reacting at 155 ℃ for 5h, directly adding ethyl acetate to dissolve a product, filtering to separate out the catalyst, performing rotary evaporation to remove ethyl acetate and ethanol to obtain a solid crude product, completely dissolving the solid with 25ml of ethanol at 55 ℃, crystallizing at 258 ℃ at low temperature, separating out colorless crystals, filtering to collect the product, drying at 45 ℃ in a vacuum oven, calculating the yield, washing the recovered catalyst with ethanol for several times, and drying in vacuum at 45 ℃ to obtain the catalyst B-3.

Dissolving 2, 4-dichlorobenzaldehyde (5.87g, 5mmol) and ethyl cyanoacetate (5.63g, 5.5mmol) in 15ml of absolute ethanol, adding a catalyst B-3, reacting at 155 ℃ for 5h, directly adding ethyl acetate to dissolve a product, filtering to separate out the catalyst, performing rotary evaporation to remove ethyl acetate and ethanol to obtain a solid crude product, completely dissolving the solid with 25ml of ethanol at 55 ℃, crystallizing at 258 ℃ at low temperature, separating out colorless crystals, filtering to collect the product, drying at 45 ℃ in a vacuum oven, calculating the yield, washing the recovered catalyst with ethanol for several times, and drying in vacuum at 45 ℃ to obtain the catalyst B-4.

Dissolving 2, 4-dichlorobenzaldehyde (5.87g, 5mmol) and ethyl cyanoacetate (5.63g, 5.5mmol) in 15ml of absolute ethanol, adding a catalyst B-4, reacting at 155 ℃ for 5h, directly adding ethyl acetate to dissolve a product, filtering to separate out the catalyst, performing rotary evaporation to remove ethyl acetate and ethanol to obtain a solid crude product, completely dissolving the solid with 25ml of ethanol at 55 ℃, crystallizing at 258 ℃ at low temperature, separating out colorless crystals, filtering to collect the product, drying at 45 ℃ in a vacuum oven, calculating the yield, washing the recovered catalyst with ethanol for several times, and drying in vacuum at 45 ℃ to obtain the catalyst B-5.

Dissolving 2, 4-dichlorobenzaldehyde (5.87g, 5mmol) and ethyl cyanoacetate (5.63g, 5.5mmol) in 15ml of absolute ethanol, adding a catalyst B-5, reacting at 155 ℃ for 5h, directly adding ethyl acetate to dissolve a product, filtering to separate out the catalyst, performing rotary evaporation to remove ethyl acetate and ethanol to obtain a solid crude product, completely dissolving the solid with 25ml of ethanol at 55 ℃, crystallizing at 258 ℃ at low temperature, separating out colorless crystals, filtering to collect the product, drying at 45 ℃ in a vacuum oven, calculating the yield, washing the recovered catalyst with ethanol for several times, and drying in vacuum at 45 ℃ to obtain the catalyst B-6.

The results of the catalyst recovery cycle testing are shown in table 2.

TABLE 2 test results for catalyst recovery cycle

As can be seen from tables 1 and 2, the solid phosphazene compound has small change amplitude of catalytic activity and excellent recycling stability after being recycled for six times.

Although the present invention has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that changes may be made in the embodiments and/or equivalents thereof without departing from the spirit and scope of the invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims (10)

1. A solid phosphazene compound is characterized by having a structure shown as a formula (1):

wherein R is_aIs a crosslinking agent, R_bis-N ═ PR₃Or is

R₁、R₂、R₃、R₄Each independently selected from H, C_1-6Alkyl radical, C_1-6Cycloalkyl radical, C_1-6Heterocycloalkyl, optionally substituted aryl, optionally substituted benzyl.

2. A preparation method of a solid phosphazene compound is characterized by comprising the following steps:

contacting phosphorus pentachloride with a compound shown as a formula (2), then contacting with ammonia gas, and finally contacting with an alkali solution to obtain a compound shown as a formula (3);

HN＝PR₃

formula (3);

II, contacting hexachlorocyclotriphosphazene with a cross-linking agent and an acid-binding agent to obtain a compound shown as a formula (4);

and III, carrying out contact reaction on the compound in the formula (3) and the compound in the formula (4) and an acid-binding agent to prepare the compound in the formula (1).

3. The method according to claim 2, wherein in step i, the contacting is performed in an anhydrous organic solvent, further, the anhydrous organic solvent is at least one selected from dichloromethane, acetonitrile, toluene, tetrahydrofuran, preferably dichloromethane;

further, the contacting is performed under a protective gas atmosphere; further, the shielding gas is selected from one of argon, nitrogen, helium, carbon dioxide and carbon monoxide, and is preferably argon.

4. The method according to claim 2, wherein in step i, the compound represented by the formula (2) is contacted with ammonia gas under the conditions: reacting for 1515 hours at-5555 ℃; further, the contact time with the alkali solution was 15515 hours;

further, the alkali is selected from one of sodium hydroxide aqueous solution, potassium hydroxide aqueous solution, sodium carbonate aqueous solution, sodium bicarbonate aqueous solution, potassium carbonate aqueous solution, potassium bicarbonate aqueous solution and ammonia water, preferably sodium hydroxide aqueous solution; further, it is characterized byThe solubility of the alkali solution is 5.551.5mol L^-1。

5. The method of claim 2, wherein in step ii, the contacting is carried out in an organic solvent; further, the organic solvent is selected from one of acetonitrile, ethanol, toluene, dimethyl sulfoxide, N' -dimethylformamide, tetrahydrofuran and dichloromethane, and is preferably acetonitrile;

further, the contacting is performed under a protective gas atmosphere; further, the protective gas is selected from one of argon, nitrogen, helium, carbon monoxide and carbon dioxide, and is preferably argon;

further, the cross-linking agent is selected from one of 4,4 '-dihydroxy diphenyl sulfone, bisphenol A, hexafluorobisphenol A, hydroquinone, phenolphthalein and bisphenol fluorene, and is preferably 4, 4' -dihydroxy diphenyl sulfone.

6. The method as claimed in claim 2, wherein in step II, the molar ratio of hexachlorocyclotriphosphazene, crosslinking agent and acid-binding agent is 1 (152) to (254), preferably 1:1.5: 3;

further, the acid-binding agent is selected from one of triethylamine, tetramethylguanidine, sodium bicarbonate, potassium bicarbonate, sodium hydroxide, potassium carbonate, sodium carbonate, potassium hydroxide and ammonia water, and is preferably triethylamine;

further, carrying out contact reaction by adopting a stirring mode, and further, stirring comprises electromagnetic stirring, mechanical stirring and ultrasonic oscillation, preferably ultrasonic oscillation;

further, the reaction temperature is 15555 ℃ and the reaction time is 255h, and 3h is preferred.

7. The method according to claim 2, wherein in step III, the acid-binding agent is selected from one of triethylamine, tetramethylguanidine, sodium carbonate, sodium bicarbonate, potassium carbonate, sodium hydroxide, potassium hydroxide and ammonia water, preferably triethylamine;

further, the contacting is carried out in an organic solvent; further, the organic solvent is selected from one of acetonitrile, toluene, dimethyl sulfoxide, N' -dimethylformamide, ethanol, tetrahydrofuran and dichloromethane, and is preferably acetonitrile;

further, the reaction temperature is 1555165 ℃, and the reaction time is 455135 h; preferably at 125 ℃ for 48 h;

further, in the step III, the mass ratio of the compound of the formula (4), triethylamine and the compound of the formula (3) is: 1: (1-2): (2-3).

8. The use of a solid phosphazene compound according to claim 1 for an organic catalytic reaction, preferably a Knoevenagel reaction or an Aldol reaction.

9. The use according to claim 8, wherein the compound is used in Knoevenagel reaction by a method comprising: contacting said compound with at least one aromatic aldehyde and ethyl cyanoacetate to obtain a Knoevenagel condensation reaction product;

further, the aromatic aldehyde is selected from one of 2-nitrobenzaldehyde, 3-nitrobenzaldehyde, 4-nitrobenzaldehyde, 2, 4-dichlorobenzaldehyde, 2, 6-dichlorobenzaldehyde, 2-chlorobenzaldehyde, 3-chlorobenzaldehyde, 4-chlorobenzaldehyde, 2-fluorobenzaldehyde, 3-fluorobenzaldehyde, 4-fluorobenzaldehyde, 2-hydroxybenzaldehyde and 2-aminobenzaldehyde;

further, the molar ratio of the aromatic aldehyde to ethyl cyanoacetate is 1 (152), preferably 1: 1.1;

further, the contacting is carried out at 55135 ℃ for 158h, preferably 155 ℃ for 5 h;

further, the contact reaction is carried out in an organic solvent, wherein the solvent is one selected from water, ethanol, toluene, tetrahydrofuran, dimethyl sulfoxide, acetonitrile and dichloromethane, and ethanol is preferred.

10. The use according to claim 8, wherein the compound is applied in an Aldol reaction by a method comprising:

(ii) participating the catalyst in the reaction of at least one aldehyde with a ketone to obtain a product;

further, the aldehydes include, but are not limited to, 2-nitrobenzaldehyde, 3-nitrobenzaldehyde, 4-nitrobenzaldehyde, 2, 4-dichlorobenzaldehyde, 2, 6-dichlorobenzaldehyde, 2-chlorobenzaldehyde, 3-chlorobenzaldehyde, 4-chlorobenzaldehyde, 2-fluorobenzaldehyde, 3-fluorobenzaldehyde, 4-fluorobenzaldehyde, 2-hydroxybenzaldehyde, 2-aminobenzaldehyde, acetaldehyde, propionaldehyde, isobutyraldehyde, n-butyraldehyde;

further, the ketones include acetone, cyclohexanone, butanone;

further, the reaction is carried out in an organic solvent; further, the organic solvent is one selected from water, ethanol, acetonitrile, tetrahydrofuran, dichloromethane, dimethyl sulfoxide, N' -dimethylformamide and toluene, and preferably ethanol;

further, the reaction conditions are as follows: the reaction is carried out at 555155 ℃ for 358h, preferably at 65 ℃ for 6h.

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