Synthesis method of 2,2,2',4',5'-pentachloroacetophenone

Abstract

The invention provides a synthesis method of 2,2,2',4',5'-pentachloroacetophenone. Raw materials comprise, by weight, 52-75 parts of 1,2,4-trichlorobenzene, 40-62 parts of dichloroacetyl chloride, 32-58 parts of a catalyst and 28-50 parts of water. A conventional temperature curve is broken, temperature change is utilized, and the catalyst is added at different time periods according to the proportion, so that the utilization rate of the catalyst is effectively improved, and the reaction degree is promoted to be more thorough; meanwhile, the catalyst adopts a carrier medium-Lewis acid compound, the carrier medium is prepared by utilizing the activity of microorganisms, and the catalyst is supported on a porous carrier, so that the activity of the catalyst is increased, the yield and the purity are improved, and the reaction rate and the reaction degree are prevented from being slowed down due to catalyst deposition in the reaction process; in addition, after the reaction is finished, an organic layer is washed and filtered by a high-efficiency filter membrane to further remove impurities, so that the purity of the product is effectively improved.

Description

technical field

[0001] The invention belongs to the field of organic chemical synthesis, in particular to a synthetic method of 2,2,2',4',5'-pentachloroacetophenone. Background technique

[0002] 2,2,2',4',5'-Pentachloroacetophenone is an important fine chemical intermediate, a raw material for many medicines and pesticides, and is widely used in medicine, pesticides and other fields.

[0003] In the prior art, the synthesis of 2,2,2',4',5'-pentachloroacetophenone is mostly based on the catalysis of dichloroacetyl chloride and 1,2,4-trichlorobenzene in Lewis acid aluminum chloride The acetylation reaction is carried out under the following conditions, and the yield is generally about 80% when the yield is good. The disadvantages of this method are inevitable, such as the yield needs to be improved, the amount of Lewis acid catalyst used remains high, and the purification means after the reaction is over A series of problems such as poor product purity lead to a series of pr...

Examples

Embodiment 1

[0023] A method for synthesizing 2,2,2',4',5'-pentachloroacetophenone. The raw materials include 63 parts of 1,2,4 trichlorobenzene, 51 parts of dichloroacetyl chloride, and 45 parts of catalyst in parts by weight. parts, 39 parts of water; the specific method is:

[0024] (1) Put the above-mentioned 1,2,4-trichlorobenzene and 30% of the above-mentioned catalyst by weight in a reaction tank and stir and mix at a stirring rate of 140rpm, keep the temperature at 50°C for 45min, and then add 60% of the catalyst dropwise in 55min For the above weight part of dichloroacetyl chloride, keep the stirring speed constant, add 40% of the above weight part of the catalyst, dropwise add the remaining weight part of dichloroacetyl chloride within 35min, raise the temperature to 70°C, keep the temperature for 1.5h, and then add the remaining weight part catalyst, heat up to 90°C, adjust the stirring speed to 380rpm, and raise the pressure of the reaction tank to 6.5×10 5 Pa, keep the reacti...

Embodiment 2

[0032] A method for synthesizing 2,2,2',4',5'-pentachloroacetophenone. The raw materials include 52 parts of 1,2,4 trichlorobenzene, 40 parts of dichloroacetyl chloride, and 58 parts of catalyst in parts by weight. part, 50 parts of water; the specific method is:

[0033] (1) Put the above-mentioned 1,2,4-trichlorobenzene and 30% of the above-mentioned catalyst by weight in a reaction tank and stir and mix at a stirring rate of 80 rpm, keep the temperature at 40°C for 55 minutes, and then add 60% of the catalyst dropwise within 60 minutes For the above weight part of dichloroacetyl chloride, keep the stirring rate constant, add 40% of the above weight part of the catalyst, dropwise add the remaining weight part of dichloroacetyl chloride within 30min, raise the temperature to 65°C, keep the temperature for 2h, and then add the remaining weight part catalyst, the temperature was raised to 95°C, the stirring speed was adjusted to 300rpm, and the pressure of the reaction tank was...

Embodiment 3

[0041] A method for synthesizing 2,2,2',4',5'-pentachloroacetophenone. The raw materials include 5 parts of 1,2,4 trichlorobenzene, 62 parts of dichloroacetyl chloride and 32 parts of catalyst in parts by weight. parts, 28 parts of water; the specific method is:

[0042] (1) Put the above-mentioned 1,2,4-trichlorobenzene and 30% of the above-mentioned catalyst by weight in a reaction tank and stir and mix them at a stirring rate of 200rpm, keep the temperature at 60°C for 35min, then add 60% of the catalyst dropwise within 50min For the above weight parts of dichloroacetyl chloride, keep the stirring rate constant, add 40% of the above weight parts of the catalyst, dropwise add the remaining weight parts of dichloroacetyl chloride within 40 minutes, raise the temperature to 75 ° C, keep it warm for 1 hour, and then add the remaining weight parts The catalyst is heated up to 85°C, the stirring speed is adjusted to 450rpm, and the pressure of the reaction tank is raised to 7×10 ...

technical field

[0001] The invention belongs to the field of organic chemical synthesis, in particular to a synthetic method of 2,2,2',4',5'-pentachloroacetophenone. Background technique

[0002] 2,2,2',4',5'-Pentachloroacetophenone is an important fine chemical intermediate, a raw material for many medicines and pesticides, and is widely used in medicine, pesticides and other fields.

[0003] In the prior art, the synthesis of 2,2,2',4',5'-pentachloroacetophenone is mostly based on the catalysis of dichloroacetyl chloride and 1,2,4-trichlorobenzene in Lewis acid aluminum chloride The acetylation reaction is carried out under the following conditions, and the yield is generally about 80% when the yield is good. The disadvantages of this method are inevitable, such as the yield needs to be improved, the amount of Lewis acid catalyst used remains high, and the purification means after the reaction is over A series of problems such as poor product purity lead to a series of pr...

Examples

Embodiment 1

[0023] A method for synthesizing 2,2,2',4',5'-pentachloroacetophenone. The raw materials include 63 parts of 1,2,4 trichlorobenzene, 51 parts of dichloroacetyl chloride, and 45 parts of catalyst in parts by weight. parts, 39 parts of water; the specific method is:

[0024] (1) Put the above-mentioned 1,2,4-trichlorobenzene and 30% of the above-mentioned catalyst by weight in a reaction tank and stir and mix at a stirring rate of 140rpm, keep the temperature at 50°C for 45min, and then add 60% of the catalyst dropwise in 55min For the above weight part of dichloroacetyl chloride, keep the stirring speed constant, add 40% of the above weight part of the catalyst, dropwise add the remaining weight part of dichloroacetyl chloride within 35min, raise the temperature to 70°C, keep the temperature for 1.5h, and then add the remaining weight part catalyst, heat up to 90°C, adjust the stirring speed to 380rpm, and raise the pressure of the reaction tank to 6.5×10 5 Pa, keep the reacti...

Embodiment 2

[0032] A method for synthesizing 2,2,2',4',5'-pentachloroacetophenone. The raw materials include 52 parts of 1,2,4 trichlorobenzene, 40 parts of dichloroacetyl chloride, and 58 parts of catalyst in parts by weight. part, 50 parts of water; the specific method is:

[0033] (1) Put the above-mentioned 1,2,4-trichlorobenzene and 30% of the above-mentioned catalyst by weight in a reaction tank and stir and mix at a stirring rate of 80 rpm, keep the temperature at 40°C for 55 minutes, and then add 60% of the catalyst dropwise within 60 minutes For the above weight part of dichloroacetyl chloride, keep the stirring rate constant, add 40% of the above weight part of the catalyst, dropwise add the remaining weight part of dichloroacetyl chloride within 30min, raise the temperature to 65°C, keep the temperature for 2h, and then add the remaining weight part catalyst, the temperature was raised to 95°C, the stirring speed was adjusted to 300rpm, and the pressure of the reaction tank was...

Embodiment 3

[0041] A method for synthesizing 2,2,2',4',5'-pentachloroacetophenone. The raw materials include 5 parts of 1,2,4 trichlorobenzene, 62 parts of dichloroacetyl chloride and 32 parts of catalyst in parts by weight. parts, 28 parts of water; the specific method is:

[0042] (1) Put the above-mentioned 1,2,4-trichlorobenzene and 30% of the above-mentioned catalyst by weight in a reaction tank and stir and mix them at a stirring rate of 200rpm, keep the temperature at 60°C for 35min, then add 60% of the catalyst dropwise within 50min For the above weight parts of dichloroacetyl chloride, keep the stirring rate constant, add 40% of the above weight parts of the catalyst, dropwise add the remaining weight parts of dichloroacetyl chloride within 40 minutes, raise the temperature to 75 ° C, keep it warm for 1 hour, and then add the remaining weight parts The catalyst is heated up to 85°C, the stirring speed is adjusted to 450rpm, and the pressure of the reaction tank is raised to 7×10 ...

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