2-Dimethylaminoisopropyl chloride(link:https://www.bloomtechz.com/synthetic-chemical/organic-intermediates/2-dimethylaminoisopropyl-chloride.html) is an organic compound with multiple uses. In addition to its applications in the fields of medicine, pesticides, materials science, and industry, 2-Dimethylaminoisopropyl chloride also plays an important role in the field of environmental science. DMAP-Cl is a common quaternary ammonium salt reagent with multiple applications. For example, it can be used as alkylation and nucleophilic reagents for quaternary ammonium salt reactions, as well as as as intermediates for certain drugs. There are various synthesis methods for this product, and our laboratory generally adopts the method of obtaining the purest and most efficient product. There are several specific methods for reference.
Method 1:
2-Dimethylamine isopropyl chloride hydrochloride (DMAP Cl) is a common quaternary ammonium salt reagent with various applications. For example, it can be used as alkylation and nucleophilic reagents for quaternary ammonium salt reactions, as well as as as intermediates for certain drugs. It can be obtained by the reaction of N, N-dimethylpropanediamine and ethyl hydrochlorite. This reaction needs to be carried out under the catalysis of antimony trichloride. The specific steps are as follows:
Chemical equation:
N. N-dimethylpropanediamine+2 HCl+SbCl3 → 2-Dimethylaminoisopropyl chloride hydrochloride+SbCl5
C6H16NCl · HCl=C6H16NCl2+H2O
Note: SbCl5 in the above equation is a byproduct that can be left behind when separating the organic phase.
Material:
N. N-Dimethylpropanediamine (DMAE, analytically pure)
Antimony trichloride (SbCl3, analytical pure)
Ethyl hydrogen chlorate (HClEt, analytical pure)
Anhydrous ether (analytical pure)
Acetone (analytical pure)
Sodium hydroxide (NaOH, analytical pure)
Water (deionized water or distilled water)
Prepare these reagents separately for subsequent reaction operations.
Step:
1. Add 15 mL of anhydrous ether, 6 mL of N, N-dimethylpropanediamine, and 0.65 g of antimony trichloride to a dry four necked bottle.
2. Stir until antimony trichloride is completely dissolved, forming a mixture.
3. Slowly add 10 mL of ethyl chlorate to the reaction mixture, while adding a magnetic stirrer, and continue stirring for 30 minutes. During the reaction process, white solids will precipitate out.
4. Transfer the reaction mixture to a dry 500 mL separation funnel and separate the organic solvent phase at the bottom layer.
5. Wash twice with sodium hydroxide solution, and neutralize each time with 50 mL of aqueous solution.
6. Remove the solvent from the organic phase to obtain a white solid product of 2-Dimethylamine isopropyl chloride hydrochloride.
7. Filter the falling solid on the filter paper and wash it with acetone.
8. The DMAP-Cl product obtained by drying can be processed using vacuum drying method in a dryer.
Method 2:
The specific steps for the reaction of N, N-dimethylamino-2-chloropropane hydrochloride obtained by chlorinating 1-dimethylamino-2-propanol with sulfoxide chloride are as follows:
The chemical equation corresponding to the above reaction is:
DMAP+SOCl2 → N, N-Dimethylamino-2-chloropropane salt+HCl salt+SO2
Among them, DMAP is the abbreviation for 1-dimethylamino-2-propanol, N, N-Dimethylamino-2-chloropropane salt represents N, N-dimethylamino-2-chloropropane salt, HCl salt represents hydrogen chloride salt, and SO2 represents sulfur dioxide.
1. Under stirring, 1-dimethylamino-2-propanol (abbreviated as DMAP) is added to sulfoxide chloride (SOCl2) to form a homogeneous solution.
2. Stir the homogeneous solution at room temperature for a certain period of time to allow the chlorination reaction to proceed fully.
3. After the reaction is completed, the completeness of the chlorination reaction is determined by titration.
4. Add an appropriate amount of alkali, such as sodium hydroxide (NaOH) or potassium hydroxide (KOH), and neutralize the generated hydrochloric acid and hydrogen chloride to obtain N, N-dimethylamino-2-chloropropane salt.
5. Separate the product N, N-dimethylamino-2-chloropropane salt from the reaction solution through distillation or other appropriate separation methods.
Method 3:
The following are the detailed steps and chemical reaction formulas for the reaction of N, N-dimethylpropanediamine with bleaching powder in the presence of sodium acetylacetate, followed by the elimination reaction of quaternary ammonium salt under the action of sodium hydroxide, to obtain 2-Dimethylaminopropyl chloride hydrochloride:
1. Firstly, add N, N-dimethylpropanediamine (abbreviated as DMMA) and sodium acetylacetate to the reactor, and then add an appropriate amount of water. DMMA is a common organic compound with a quaternary ammonium salt structure, while sodium acetylacetate is used as a catalyst for the reaction. Heat the mixture under stirring to reflux temperature (about 80 ℃) and maintain it at this temperature for about 2 hours, allowing DMMA and sodium acetylacetate to fully react.
2. During this process, DMMA reacts with bleaching powder (usually sodium hypochlorite or sodium hypochlorite generated by the reaction of chlorine gas with sodium hydroxide) to produce 2-Dimethylaminoisopropyl chloride hydrochloride. The specific chemical reaction equation is:
CH3-CH (COOCH3) - COOH+CH3-N (CH3) - CH2CH3 → CH3-CH (COOCH3) - N (CH3) - CH2CH3+H2O
3. Next, add sodium hydroxide to the above reaction solution, adjust the pH value to alkaline (such as pH=9), and then heat it to reflux temperature (about 80 ℃) under stirring, and maintain this temperature for about 2 hours to cause the generated quaternary ammonium salt to undergo elimination reaction, obtaining 2-Dimethylaminoisopropyl chloride hydrochloride.
During this process, sodium hydroxide is used as an alkaline catalyst to promote the elimination reaction of quaternary ammonium salts, generating the required 2-Dimethylamine isopropyl chloride hydrate. The specific chemical reaction equation is:
CH3-CH (COOCH3) - N (CH3) - CH2CH3+NaOH → CH3-N (CH3) - CH2CH2Cl · HCl+CH3-CH (COONa) - COONa
In the above reaction, sodium acetylacetate is used as a catalyst to promote the reaction between N, N-dimethylpropanediamine and bleaching powder; Sodium hydroxide is used to regulate the pH value of the reaction solution and promote the elimination reaction of quaternary ammonium salts. By controlling the reaction temperature, time, pH value, and other conditions, the process of the reaction can be optimized to improve the yield and purity of 2-Dimethylamine isopropyl chloride.
It should be noted that this reaction may generate a large amount of heat and gas, so it should be operated under appropriate safety measures to avoid potential hazards. In addition, the use of bleaching powder and sodium hydroxide as raw materials also requires attention to safety and storage issues.
In general, by reacting N, N-dimethylpropanediamine with bleaching powder in the presence of sodium acetylacetate, followed by the elimination reaction of quaternary ammonium salt in the presence of sodium hydroxide, 2-Dimethylaminoisopropyl chloride can be prepared. This method has high yield and purity, and is an effective method for preparing 2-Dimethylamine isopropyl chloride hydrochloride.