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CN-121974810-A - Method for preparing dihydroxyethyl cyclohexylamine by autocatalysis

CN121974810ACN 121974810 ACN121974810 ACN 121974810ACN-121974810-A

Abstract

The invention relates to the technical field of synthesis of dihydroxyethyl cyclohexylamine, and provides a method for preparing dihydroxyethyl cyclohexylamine by autocatalysis. The invention carries out self-catalytic addition reaction on cyclohexane and ethylene oxide to obtain dihydroxyethyl cyclohexane, wherein the self-catalytic addition reaction comprises a low-temperature initiation stage, a high-temperature reaction stage and a curing stage in sequence. According to the invention, ethylene oxide occupies the positions of two active hydrogen of amino in cyclohexylamine through a low-temperature initiation stage to form a large amount of physical and chemical adsorption, and then the temperature is increased to enable the addition reaction to carry out preferential addition according to the reaction activity, so that the preferential and balanced addition of one ethylene oxide on the two active hydrogen of cyclohexylamine is finally ensured, and the generation of polyethoxy cyclohexylamine is avoided. The method provided by the invention has the advantages that no catalyst is required to be added, the self-catalysis is formed through the control of the reaction conditions, the reaction is rapid, the operation is simple, the refining process is omitted, the purity of the target product is high, and the aim of atomic-level directional synthesis is fulfilled.

Inventors

  • CHE FEI
  • Xiao Chuanbin
  • Che Fangyuan
  • Ran Zhenquan

Assignees

  • 上海邦高化学有限公司

Dates

Publication Date
20260505
Application Date
20241031

Claims (10)

  1. 1. A method for preparing dihydroxyethyl cyclohexylamine by autocatalysis, which is characterized by comprising the following steps: carrying out an autocatalytic addition reaction on cyclohexylamine and ethylene oxide to obtain dihydroxyethyl cyclohexylamine, wherein the molar ratio of the cyclohexylamine to the ethylene oxide is 0.8:1-1:0.8, and the autocatalytic addition reaction comprises a low-temperature initiation stage, a high-temperature reaction stage and a curing stage in sequence; The initial temperature of the low-temperature initiation stage is 40-50 ℃ and the end temperature is 100-105 ℃, and the ethylene oxide consumption of the low-temperature initiation stage is 5-25% of the total mass of the ethylene oxide; The temperature of the high-temperature reaction stage is 130-150 ℃, and the consumption of the ethylene oxide of the high-temperature reaction stage is 75-95% of the total mass of the ethylene oxide.
  2. 2. The method of claim 1, wherein the pressure in the low temperature initiation stage is from atmospheric pressure to 0.2MPa.
  3. 3. The method of claim 1, wherein the low temperature initiation stage has a ramp rate of 0.2 to 3 ℃ per minute.
  4. 4. The method according to claim 1, wherein the low-temperature initiation stage comprises a first stage and a second stage which are sequentially carried out, wherein the initial temperature of the first stage is 40-50 ℃, the final temperature is 80-85 ℃, the temperature rising rate is 0.3-0.5 ℃ per minute, ethylene oxide is added once every 8-12 ℃ of the first stage, the addition amount of each time is 1-5% of the total mass of the ethylene oxide, the initial temperature of the second stage is 80-85 ℃, the final temperature is 100-105 ℃, the temperature rising rate is 0.2-0.4 ℃ per minute, the addition amount of each time is 1-5% of the total mass of the ethylene oxide is added once every 8-12 ℃ of the second stage.
  5. 5. The method of claim 1, wherein the low temperature initiation stage comprises a sequential warm-up stage and a cool-warm up cycle stage, the warm-up stage comprising a warm-up from 40-50 ℃ to 100-105 ℃ at a rate of 0.5-1 ℃ per minute, the cool-warm up cycle stage comprising at least 1 cool-warm up operation, the cool-warm up operation comprising a cool-down to 60 ℃ followed by a warm-up to 100-105 ℃ at a rate of 0.5-1 ℃ per minute.
  6. 6. The method according to claim 5, wherein the number of cooling-warming operations is 1 to 8.
  7. 7. The method according to claim 5 or 6, wherein ethylene oxide is added once every 8-12 ℃ of temperature rise in the temperature rising stage, and the addition amount of each time is 1-5% of the total mass of the ethylene oxide; In the cooling-heating cycle stage, ethylene oxide is added for 2-5 times in the cooling-heating operation process each time, and the addition amount of each time is 1-5% of the total mass of the ethylene oxide.
  8. 8. The method according to claim 1, wherein the pressure in the high temperature reaction stage is 0.1 to 0.2mpa; The ethylene oxide is added continuously or in batches at the high-temperature reaction stage, wherein the batch addition mode is that ethylene oxide is added once when the pressure is lower than 0.1MPa, and the addition amount of each time is 2-8% of the total mass of the ethylene oxide.
  9. 9. The method according to claim 1, wherein the curing stage is performed at a temperature of 110-130 ℃ for a time of 20-60 min.
  10. 10. The method according to claim 1, wherein the aging stage is followed by an adjustment stage, the adjustment stage comprising adding ethylene oxide to the material obtained after the aging stage, reacting under the conditions of the high temperature reaction stage, and then aging again.

Description

Method for preparing dihydroxyethyl cyclohexylamine by autocatalysis Technical Field The invention relates to the technical field of dihydroxyethyl cyclohexylamine synthesis, in particular to a method for preparing dihydroxyethyl cyclohexylamine by autocatalysis. Background Dihydroxyethyl cyclohexylamine is a multifunctional component and is highly compatible with other additives, co-emulsifiers and neutralizing agents for metal working fluids. The dihydroxyethyl cyclohexylamine has good emulsifying property, can improve the dispersibility and stability of emulsion, has high boiling point, is a low-volatility component, can be used for high-temperature operation, can stabilize the emulsion, and prolongs the service life of the emulsion under severe conditions. In addition, dihydroxyethyl cyclohexylamine can be used as a medical intermediate and has important application in the aspect of medicine synthesis. At present, dihydroxyethyl cyclohexylamine is usually obtained by an addition reaction of cyclohexylamine and ethylene oxide, wherein the addition reaction is required to be carried out under the condition of an acidic or alkaline catalyst, and the target product is obtained by purifying by a refining method such as rectification and the like at the later stage. The catalyst can improve the ring-opening reaction rate of the ethylene oxide and promote the effective combination of the cyclohexylamine and the ethylene oxide, thereby generating a target product. However, this method has disadvantages in that the catalyst cost is high, byproducts are much, excessive impurities may affect the product appearance and the application in the high-precision fields such as medicine, etc., and the refining process consumes high energy and takes a long time. Disclosure of Invention In view of this, the present invention provides a method for autocatalytically preparing dihydroxyethyl cyclohexylamine. The method provided by the invention does not need to adopt a catalyst, has few byproducts, does not need to be refined, and has high product purity and low preparation cost. In order to achieve the above object, the present invention provides the following technical solutions: A method for autocatalytically preparing dihydroxyethyl cyclohexylamine, comprising the steps of: carrying out an autocatalytic addition reaction on cyclohexylamine and ethylene oxide to obtain dihydroxyethyl cyclohexylamine, wherein the molar ratio of the cyclohexylamine to the ethylene oxide is 0.8:1-1:0.8, and the autocatalytic addition reaction comprises a low-temperature initiation stage, a high-temperature reaction stage and a curing stage in sequence; The initial temperature of the low-temperature initiation stage is 40-50 ℃ and the end temperature is 100-105 ℃, and the ethylene oxide consumption of the low-temperature initiation stage is 5-25% of the total mass of the ethylene oxide; The temperature of the high-temperature reaction stage is 130-150 ℃, and the consumption of the ethylene oxide of the high-temperature reaction stage is 75-95% of the total mass of the ethylene oxide. Preferably, the pressure in the low-temperature initiation stage is normal pressure to 0.2MPa. Preferably, the temperature rising rate of the low-temperature initiation stage is 0.2-3 ℃ per minute. Preferably, the low-temperature initiation stage comprises a first stage and a second stage which are sequentially carried out, wherein the initial temperature of the first stage is 40-50 ℃, the end temperature is 80-85 ℃, the temperature rising rate is 0.3-0.5 ℃ per minute, ethylene oxide is added once every 8-12 ℃ in the first stage, the addition amount of each time is 1-5% of the total mass of the ethylene oxide, the initial temperature of the second stage is 80-85 ℃, the end temperature is 100-105 ℃, the temperature rising rate is 0.2-0.4 ℃ per minute, the addition amount of each time is 1-5% of the total mass of the ethylene oxide every 8-12 ℃ in the second stage. The low-temperature initiation stage comprises a temperature rising stage and a temperature reduction-temperature rising circulation stage which are sequentially carried out, wherein the temperature rising stage comprises a temperature rising process of heating from 40-50 ℃ to 100-105 ℃ at a rate of 0.5-1 ℃ per minute, the temperature reduction-temperature rising circulation stage comprises at least 1 temperature reduction-temperature rising operation, and the temperature reduction-temperature rising operation comprises a temperature reduction process of cooling to 60 ℃ firstly and then heating to 100-105 ℃ at a rate of 0.5-1 ℃ per minute. Preferably, the cooling-heating operation is performed for 1 to 8 times. Preferably, in the heating stage, ethylene oxide is added once at the temperature of 8-12 ℃ every time, and the addition amount of each time is 1-5% of the total mass of the ethylene oxide; In the cooling-heating cycle stage, ethylene oxide is added for 2-5 times in the cooling-heating operation pro