CN110194730A - Application of the DUT-67 (Zr) in photochemical catalytic oxidation aminomethyl phenyl thioether preparation methyl phenyl sulfoxide - Google Patents

Abstract

The invention discloses the application of Zr-MOF (DUT-67) in photocatalytic oxidation of methyl phenyl sulfide to prepare methyl phenyl sulfoxide, and belongs to the field of photocatalysis technology. DUT‑67(Zr) is a metal-organic framework material with high thermal and chemical stability. The present invention uses DUT-67(Zr) as a photocatalyst for organic synthesis for the first time, further expanding the application of highly stable Zr-based MOF in the field of photocatalysis. Under the full band and 360nm wavelength light source, DUT‑67(Zr) showed high activity in the photocatalytic oxidation of methyl phenyl sulfide, which can successfully solve the complex reaction process, high toxicity and easy Pollution, low efficiency problems. The invention has the advantages of simple process, environmental protection, high yield, stable and high-efficiency catalytic process, can be applied to large-scale actual production, and has broad potential.

Description

DUT-67(Zr) in Photocatalytic Oxidation of Methyl Phenyl Sulfide to Methyl Phenyl Sulfoxide Applications

technical field

The invention belongs to the technical field of photocatalysis, and specifically describes the application of a highly stable Zr-based metal-organic framework structure DUT-67 (Zr) in the field of photocatalysis.

Background technique

Metal-organic frameworks (MOFs) are three-dimensional porous network structures assembled by metal ions and organic ligands, which have the advantages of large specific surface area, high stability and strong controllability. In recent years, MOFs have been widely used in photocatalytic organic synthesis, _CO2 reduction, photolysis of water for hydrogen production, and degradation of organic matter, etc. Zr-based MOFs stand out among many MOFs due to their large specific surface area and excellent structural stability. So far, most studies have focused on the modification of UiO-66, and it is necessary to expand the application of new Zr-based MOFs in the field of photocatalysis. Based on the above reasons, DUT-67(Zr), as a potential member of Zr-based MOF, provides a new idea for the selection of photocatalysts.

As an organic intermediate of medicine, pesticide and expensive materials, sulfoxide has attracted more and more attention. Selective oxidation of thioether compound is one of the most common synthetic methods. However, traditional industrial synthesis methods have disadvantages such as high toxicity, low efficiency, and poor selectivity, and efficient and clean photocatalytic technology has emerged. Combining the advantages of DUT-67(Zr) itself and the photocatalytic effect, this will better solve the difficult problem in the process of oxidizing methyl phenyl sulfide to synthesize methyl phenyl sulfoxide.

Contents of the invention

The purpose of the present invention is to expand the application of Zr-based MOFs in the field of photocatalysis, and provides DUT-67(Zr) photocatalytic oxidation of methyl phenyl sulfide to synthesize methyl phenyl sulfoxide. The conversion rate of the reactant and the selectivity of the product are excellent, the catalyst has high stability, the operation method is simple and controllable, and has a good application prospect.

To achieve the above object, the present invention takes the following technical solutions:

A metal-organic framework material DUT-67(Zr) with photocatalytic oxidation of methyl phenyl sulfide, the chemical formula is Zr ₆ O ₄ (OH) ₄ (TDC) ₄ (CH ₃ COO) ₄ .

The metal-organic framework material DUT-67(Zr) is applied to the photocatalytic oxidation of methyl phenyl sulfide to prepare methyl phenyl sulfoxide, wherein the DUT-67(Zr) is used as a photocatalytic reactant; The specific steps are: Weigh 10 mg metal-organic framework material DUT-67(Zr) catalyst into the reactor, add 11.7 μL methyl phenyl sulfide, 0.1 mL methanol and 1.5 mL benzotrifluoride, feed oxygen, and Under normal temperature conditions, the light source is turned on to carry out the photocatalytic reaction, and the product is detected and analyzed by gas chromatography; the light source is a 300 W xenon lamp.

The application method is as follows: using trifluorotoluene and methanol as reaction solvents, oxygen as an oxidant, and photocatalytic reaction at room temperature for 8 h; the volume ratio of trifluorotoluene and methanol is 15:1.

Two kinds of reaction results: 1) When the light source range is full band, the conversion rate of methyl phenyl sulfide is 99%, and the selectivity of methyl phenyl sulfoxide is 99%. 2) When the light source wavelength is greater than 360 nm, the conversion rate of methyl phenyl sulfide is 95%, and the selectivity of methyl phenyl sulfoxide is 99%.

Among them, DUT-67(Zr) was prepared by a one-pot hydrothermal method. Specific steps: Dissolve ZrCl ₄ (1 mmol, 230 mg) in a mixed solution of 12.5 mL DMF (N,N-dimethylformamide) and 12.5 mL NMP (N-methylpyrrolidone), and stir for 10 min until ZrCl ₄ was completely dissolved, and H ₂ TDC (2,5-thiophene dicarboxylic acid) (0.67 mmol, 110 mg) was added to the mixed solution and stirred for 5 min, then 7 mL of acetic acid was added as a regulator, and the stirring was continued for 10 min. Finally, the suspension mixture was transferred to a 50 mL hydrothermal reaction kettle, placed in an oven, and reacted at 120 °C for 48 h. The solid product was obtained after filtration, washed with DMF and methanol several times, and then dried in vacuum at 100°C.

The significant advantages of this experiment are:

1) This invention first applies DUT-67(Zr) to the field of photocatalysis and realizes the efficient oxidation of methyl phenyl sulfide to synthesize methyl phenyl sulfoxide.

2) The experimental process of the present invention is simple and easy to implement, and has strong generalizability.

Description of drawings

Fig. 1 is the X-ray diffraction figure (XRD) of catalyst DUT-67 (Zr) of the present invention.

Fig. 2 is the ultraviolet-visible diffuse reflectance figure (DRS) of catalyst DUT-67 (Zr) of the present invention.

Fig. 3 is a schematic diagram of Zr-O clusters of the catalyst DUT-67(Zr) of the present invention.

Fig. 4 is a comparison experiment diagram of different light sources for the photocatalytic oxidation of methyl phenyl sulfide with DUT-67 (Zr) as the catalyst of the present invention; wherein the light source range of 1 is the whole band; the light source wavelength of 2 is greater than 360 nm.

Detailed ways

In order to make the content of the present invention easier to understand, the following are several embodiments of the present invention, but the present invention is not limited thereto.

The preparation of embodiment 1 DUT-67 (Zr) photocatalyst

Dissolve ZrCl ₄ (1 mmol, 230 mg) in a mixed solution of 25 mL (DMF:NMP=1:1), stir for 10 min until ZrCl ₄ is completely dissolved, add H ₂ TDC (0.67 mmol, 110 mg) into the mixed solution After stirring for 5 min, 7 mL of acetic acid was added as a regulator, and stirring was continued for 10 min. Finally, the suspension mixture was transferred to a 50 mL hydrothermal reaction kettle, placed in an oven, and reacted at 120 °C for 48 h. The solid product was obtained after filtration, washed with DMF and methanol for 3-5 times, and dried under vacuum at 100°C.

Fig. 1 is the X-ray diffraction spectrum of the photocatalyst DUT-67 (Zr) of the present invention, and it can be known by comparison that the synthesized sample is a pure phase. Fig. 2 shows the ultraviolet-visible diffuse reflection spectrogram of the photocatalyst DUT-67 (Zr) of the present invention, it can be seen from the figure that DUT-67 (Zr) can absorb sunlight effectively. Fig. 3 has shown the Zr-O cluster structure figure of catalyst DUT-67 (Zr) of the present invention, can find out from the figure that DUT-67 (Zr) is made of a Zr ₆ regular octahedra and 8 2,5-thiophene two Reo topology linked by carboxylic acid ligands.

Example 2 DUT-67(Zr) photocatalytic oxidation of methyl phenyl sulfide to prepare methyl phenyl sulfoxide

The prepared Zr-based metal-organic framework DUT-67(Zr) was used as a photocatalyst to oxidize methyl phenyl sulfide. Weighed 10 mg catalyst into the reactor, added 11.7 μL methyl phenyl sulfide, 0.1 mL methanol and 1.5 mL of trifluorotoluene was fed with oxygen, and at room temperature, the light source was turned on for photocatalytic reaction. The product was detected and analyzed by gas chromatography. The light source used in the experiment was a 300 W xenon lamp.

The conversion rate of methyl phenyl sulfide and the selectivity of methyl phenyl sulfoxide are shown in Figure 4. It can be seen from the figure that when there is a catalyst, under the full band condition (1), methyl phenyl The conversion rate of thioether reached 99% and the selectivity reached 99% after 8 hours of light irradiation; when using a filter to ensure that the incident light range was above 360 nm (2), the conversion rate of methyl phenyl sulfide after 8 hours of light irradiation Up to 95%, selectivity up to 99%.

The above descriptions are the preferred experimental examples of this experiment, and all equivalent changes and modifications made according to the scope of the patent application of the present invention should fall within the scope of the present invention.

Claims (5)

1. a kind of metal-organic framework materials DUT-67 (Zr) with photochemical catalytic oxidation aminomethyl phenyl thioether, it is characterised in that: Chemical formula is Zr₆O₄(OH)₄(TDC)₄(CH₃COO)₄。

2. a kind of preparation method of the metal-organic framework materials DUT-67 (Zr) with photochemical catalytic oxidation aminomethyl phenyl thioether, It is characterized in that, specifically includes the following steps: by the ZrCl of 1 mmol₄It is dissolved in the DMF/NMP mixed solution of 25 mL, stirs 10 min to ZrCl₄It is completely dissolved, by the H of 0.67 mmol₂After TDC is added in mixed solution and stirs 5 min, 7mL is added Acetic acid continues to stir 10 min as regulator；Finally suspended mixed liquor is transferred in the hydrothermal reaction kettle of 50 mL, juxtaposition In baking oven, in 120 DEG C of 48 h of reaction；Solid product is obtained after filtering, 100 DEG C of vacuum after being washed 3-5 times with DMF and methanol Drying；

In the DMF/NMP mixed solution, the volume ratio of DMF and NMP are 1:1.

3. a kind of metal-organic framework materials DUT-67 (Zr) as described in claim 1 is in photochemical catalytic oxidation aminomethyl phenyl sulphur Ether prepares the application in methyl phenyl sulfoxide, which is characterized in that the DUT-67 (Zr) is used as light-catalyzed reaction agent.

4. according to application described in right 2, it is characterised in that: utilizing benzotrifluoride and methanol is reaction dissolvent, and oxygen is as oxygen Agent, under normal temperature conditions light-catalyzed reaction 8h；The volume ratio of the benzotrifluoride and methanol is 15:1.

5. according to application described in right 2, it is characterised in that: specific steps are as follows: weigh 10 mg metal-organic framework materials 11.7 μ L aminomethyl phenyl thioethers, 0.1 mL methanol and 1.5 mL fluoroforms are added in reactor in DUT-67 (Zr) catalyst Benzene is passed through oxygen, under normal temperature conditions, opens light source and carries out light-catalyzed reaction, product passes through gas chromatographic detection and analyzes；Institute State the xenon lamp that light source is 300 W.