Synthesis method of o-chloronitrosobenzene

Abstract

The invention relates to a synthesis method of o-chloronitrosobenzene. The synthesis method of o-chloronitrosobenzene comprises the following steps: weighing raw materials o-chloroaniline and a catalyst 1% Ru / Al2O3; the method comprises the following steps: adding o-chloroaniline and a catalyst 1% Ru / Al2O3 into a reaction bottle, then adding a solvent toluene, introducing oxygen under heating reflux to enable continuous bubbles to be released from a bubbler, and reacting for 8 hours; and cooling, recovering the solvent, and directly rectifying to obtain the product o-chloronitrosobenzene. The method has the advantages that o-chloroaniline is used as a raw material, amino in the raw material is converted into nitroso and oxidized into o-chloronitrobenzene under the catalysis of the catalyst 1% Ru / Al2O3, the product o-chloronitrobenzene can be obtained through reaction in a new catalysis mode, and the yield is increased.

Description

Technical Field

[0001] The invention relates to the technical field of organic synthesis, and in particular to a method for synthesizing o-chloronitrosobenzene. Background Art

[0002] o-Chloronitrosobenzene is an organic synthesis intermediate and is a pale yellow solid.

[0003] In the prior art, the synthesis of o-chloronitrosobenzene usually adopts hydrogen peroxide, potassium persulfate oxidation, etc. to convert the amino group in the raw material into nitroso to obtain o-chloronitrosobenzene, and the yield is low. The present invention provides a new synthesis method of o-chloronitrosobenzene, which obtains o-chloronitrosobenzene by ruthenium catalytic oxidation. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a method for synthesizing o-chloronitrosobenzene, which can solve the problem of low yield in the prior art of generally using hydrogen peroxide and potassium persulfate to oxidize and form nitroso groups.

[0005] In order to solve the above technical problems, the technical solution of the present invention is: comprising the following steps: S1. Weigh the raw material o-chloroaniline and catalyst 1%Ru / Al 2 O 3 ; S2. Add o-chloroaniline and catalyst 1% Ru / Al to the reaction bottle. 2 O 3 Then add toluene solvent, heat and reflux, introduce oxygen, so that continuous bubbles are released from the bubbler, and react for 8 hours. The reaction process is: ; S3, cooling, recovering the solvent and then directly distilling to obtain the product o-chloronitrosobenzene.

[0006] Furthermore, the o-chloroaniline and the catalyst 1%Ru / Al 2 O 3 The mass ratio is 15-45:1.

[0007] Furthermore, the mass ratio of the solvent toluene to o-chloroaniline is 100:125-130.

[0008] Furthermore, in step S2, the temperature is heated to 110 degrees and the flow rate of oxygen introduced is 2 ml / s.

[0009] Furthermore, in step S3, the temperature is cooled to 25 degrees.

[0010] The advantages of the present invention are: the present invention uses o-chloroaniline as raw material, in the catalyst Ru / Al 2 O 3Under catalysis, the amino group in the raw material is converted into nitroso group and oxidized into o-chloronitrosobenzene. The product o-chloronitrosobenzene can be obtained by reaction using a new catalytic method with improved yield. DETAILED DESCRIPTION

[0011] In order to make the purpose, technical scheme and advantages of the present invention more clear, the present invention is further described in detail below in conjunction with specific implementation methods. The following examples can enable technicians in this field to understand the present invention more comprehensively, but the present invention is not limited to the scope of the embodiments.

[0012] This specific implementation adopts the following technical scheme: The synthesis method of o-chloronitrosobenzene comprises the following steps: S1. Weigh the raw material o-chloroaniline and catalyst 1%Ru / Al 2 O 3 , o-chloroaniline and catalyst 1%Ru / Al 2 O 3 The mass ratio is 15-45:1.

[0013] S2. Add o-chloroaniline and catalyst 1% Ru / Al to the reaction bottle. 2 O 3 , then add solvent toluene, the mass ratio of solvent toluene to o-chloroaniline is 100:125-130, and oxygen is introduced under heating reflux, heated to 110 degrees, the flow rate of oxygen is 2ml / s, so that continuous bubbles are released from the bubbler, and react for 8 hours. The reaction process is: ; S3, cooling to 25 degrees, recovering the solvent and then directly distilling to obtain the product o-chloronitrosobenzene. Example

[0014] Add 127 g of o-chloroaniline and 1% Ru / Al catalyst into the reaction bottle. 2 O 3 5 grams, add 100 ml of solvent toluene, heat and reflux, introduce oxygen, heat to 110 degrees, the flow rate of oxygen is 2 ml / s, so that continuous bubbles are released from the bubbler, react for 8 hours, cool to 25 degrees, recover the solvent and directly distill to obtain a light yellow solid, mp64-65℃, which is identified as o-chloronitrosobenzene by nuclear magnetic resonance, mass spectrometry and elemental analysis, with a yield of 86%.

[0015] The structural analysis of the obtained product o-chloronitrosobenzene is shown in the following table.

[0016]

[0017] Embodiment 2: Add 127 g of o-chloroaniline and 1% Ru / Al catalyst into the reaction bottle.2 O 3 3 grams, add 100 ml of solvent toluene, heat and reflux, introduce oxygen, heat to 110 degrees, the flow rate of oxygen is 2 ml / s, so that continuous bubbles are released from the bubbler, react for 8 hours, cool to 25 degrees, recover the solvent and directly distill to obtain a light yellow solid, mp64-65℃, which is identified as o-chloronitrosobenzene by nuclear magnetic resonance, mass spectrometry and elemental analysis, with a yield of 80%.

[0018] Embodiment 3: Add 127 g of o-chloroaniline and 1% Ru / Al catalyst into the reaction bottle. 2 O 3 8 grams, add 100 ml of solvent toluene, heat and reflux, introduce oxygen, heat to 110 degrees, the flow rate of oxygen is 2 ml / s, so that continuous bubbles are released from the bubbler, react for 8 hours, cool, recover the solvent and directly distill to obtain a light yellow solid, mp64-65℃, which is identified as o-chloronitrosobenzene by nuclear magnetic resonance, mass spectrometry and elemental analysis, with a yield of 85%.

[0019] Comparative Example 1: Add 127 g of o-chloroaniline and 1% Ru / Al catalyst into the reaction bottle. 2 O 3 1 gram, add 100 ml of solvent toluene, heat and reflux, introduce oxygen, heat to 110 degrees, the flow rate of oxygen is 2 ml / s, so that continuous bubbles are released from the bubbler, react for 8 hours, cool to 25 degrees, recover the solvent and directly distill to obtain a light yellow solid, mp64-65℃, identified as o-chloronitrosobenzene by NMR, mass spectrometry and elemental analysis, with a yield of 55%.

[0020] From the comparison between Examples 1-3 and Comparative Example 1, it can be seen that the catalyst 1%Ru / Al 2 O 3 The mass ratio of the added amount to o-chloroaniline should be in the range of 1:15-45. If the added amount is too small, it will lead to incomplete reaction and low reaction yield.

[0021] The above shows and describes the basic principles and main features of the present invention and the advantages of the present invention. It should be understood by those skilled in the art that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention to be protected. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A method for synthesizing o-chloronitrosobenzene, characterized in that: The following steps are involved: S1, weigh the raw material o-chloroaniline and the catalyst 1%Ru / Al2O3; S2, add o-chloroaniline, catalyst 1% Ru / Al2O3, and solvent toluene to the reaction bottle, heat and reflux, introduce oxygen, so that continuous bubbles are released from the bubbler, react for 8 hours, the reaction process is: ; S3, cooling, recovering the solvent and then directly distilling to obtain the product o-chloronitrosobenzene.

2. A method for synthesizing o-chloronitrosobenzene according to claim 1, characterized in that: The mass ratio of the o-chloroaniline to the catalyst 1%Ru / Al2O3 is 15-45:

1.

3. A method for synthesizing o-chloronitrosobenzene according to claim 1, characterized in that: The mass ratio of the solvent toluene to o-chloroaniline is 100:125-130.

4. A method for synthesizing o-chloronitrosobenzene according to claim 1, characterized in that: In step S2, the temperature is heated to 110 degrees and the flow rate of oxygen introduced is 2 ml / s.

5. A method for synthesizing o-chloronitrosobenzene according to claim 1, characterized in that: In step S3, cooling is performed to 25 degrees.

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