### **Material preparation**
#### **Chemical reagent:**
1. **Phenylacetone: 100 g (0.746 mol)**
2. **Methylamine solution (40%): 56 g (0.746 mol)**
3. **Sodium borohydride (NaBH4): 30 g (in excess of appropriate amount)**
4. **Solvent: methanol or ethanol (anhydrous, 500 mL)**
5. **Dilute hydrochloric acid (HCl, 10%): 200 mL**
6. **Ether: 500 mL (for extraction)**
7. **Sodium sulfate anhydrous (Na2SO4): appropriate amount (dried organic phase)**
---
### **Experimental Steps**
#### **Step 1: Prepare the reaction mixture**
1. **Configure the reaction solution:**
- In a 1 L reaction flask, add 500 mL of anhydrous methanol or ethanol.
- Add 100 g of phenylacetone and stir to dissolve.
- Slowly add 56 g methylamine solution (40%) and control the temperature at **0-5°C** (cooling with ice bath).
---
#### **Step 2: Add sodium borohydride**
1. **Add sodium borohydride in batches:**
- Under stirring, add 30 g of sodium borohydride powder in batches and keep the temperature at **0-10°C**.
- Observe whether there is a gas release after adding sodium borohydride each time to ensure that the reaction is gentle.
2. **Complete the reduction reaction:**
- After the feeding is completed, continue the stirring reaction **2-3 hours** to let the temperature slowly rise to room temperature (~25°C).
---
####**Step 3: Reaction termination and neutralization**
1. **Acidification reaction solution:**
- Slowly add dilute hydrochloric acid (10% HCl) and adjust the pH of the solution to **6-7** to stabilize the amino group structure of the product and terminate the reduction reaction.
2. **Desolvent:**
- Remove most of the solvent (methanol or ethanol) through the rotary evaporator.
---
#### **Step 4: Extraction and Purification**
1. **Extraction product:**
- Add the remaining reaction solution to the liquid separation funnel and extract the product with **ether** (3 times, about 100 mL each time).
- Collect the organic phase and wash it with water twice to remove salt and by-products.
2. **Dry organic phase:**
- Dry the organic phase with **anhydrous sodium sulfate** and filter out the desiccant.
3. ** Evaporation solvent:**
- Use a rotary evaporator or decompression distillation to evaporate ether to obtain crude products.
4. **Purified products:**
- It can be further purified by recrystallization (mixed solvent with ethanol/water) or distillation.
---
### **Theoretical output and actual yield**
1. **Theoretical output:**
- Molecular weight: 149.23 g/mol
- Theoretical output = \( 0.746 \times 149.23 = 111.3 \, \text{g} \)
2. **Actual yield:**
- The yield of reducing amination reaction using sodium borohydride is usually **75-85%**, so the actual product is about **85 g - 95 g**.
#### **Chemical reagent:**
1. **Phenylacetone: 100 g (0.746 mol)**
2. **Methylamine solution (40%): 56 g (0.746 mol)**
3. **Sodium borohydride (NaBH4): 30 g (in excess of appropriate amount)**
4. **Solvent: methanol or ethanol (anhydrous, 500 mL)**
5. **Dilute hydrochloric acid (HCl, 10%): 200 mL**
6. **Ether: 500 mL (for extraction)**
7. **Sodium sulfate anhydrous (Na2SO4): appropriate amount (dried organic phase)**
---
### **Experimental Steps**
#### **Step 1: Prepare the reaction mixture**
1. **Configure the reaction solution:**
- In a 1 L reaction flask, add 500 mL of anhydrous methanol or ethanol.
- Add 100 g of phenylacetone and stir to dissolve.
- Slowly add 56 g methylamine solution (40%) and control the temperature at **0-5°C** (cooling with ice bath).
---
#### **Step 2: Add sodium borohydride**
1. **Add sodium borohydride in batches:**
- Under stirring, add 30 g of sodium borohydride powder in batches and keep the temperature at **0-10°C**.
- Observe whether there is a gas release after adding sodium borohydride each time to ensure that the reaction is gentle.
2. **Complete the reduction reaction:**
- After the feeding is completed, continue the stirring reaction **2-3 hours** to let the temperature slowly rise to room temperature (~25°C).
---
####**Step 3: Reaction termination and neutralization**
1. **Acidification reaction solution:**
- Slowly add dilute hydrochloric acid (10% HCl) and adjust the pH of the solution to **6-7** to stabilize the amino group structure of the product and terminate the reduction reaction.
2. **Desolvent:**
- Remove most of the solvent (methanol or ethanol) through the rotary evaporator.
---
#### **Step 4: Extraction and Purification**
1. **Extraction product:**
- Add the remaining reaction solution to the liquid separation funnel and extract the product with **ether** (3 times, about 100 mL each time).
- Collect the organic phase and wash it with water twice to remove salt and by-products.
2. **Dry organic phase:**
- Dry the organic phase with **anhydrous sodium sulfate** and filter out the desiccant.
3. ** Evaporation solvent:**
- Use a rotary evaporator or decompression distillation to evaporate ether to obtain crude products.
4. **Purified products:**
- It can be further purified by recrystallization (mixed solvent with ethanol/water) or distillation.
---
### **Theoretical output and actual yield**
1. **Theoretical output:**
- Molecular weight: 149.23 g/mol
- Theoretical output = \( 0.746 \times 149.23 = 111.3 \, \text{g} \)
2. **Actual yield:**
- The yield of reducing amination reaction using sodium borohydride is usually **75-85%**, so the actual product is about **85 g - 95 g**.