If anyone wants to try it’s just theoretical, I got from a friend .
Hopefully a novel way for MDP2P
Materials and Chemicals:
- **Catechol**: 0.36 grams
- **Formaldehyde (37% aqueous solution)**: Approximately 0.4 mL
- **Propionic Acid**: Approximately 1.1 mL
- **Acetic Anhydride**: Approximately 1.1 mL
- **Zinc Chloride (ZnCl2)**: 0.76 grams
- **Dichloromethane (DCM)**: Approximately 20 mL
- **p-Toluenesulfonic acid (PTSA)**: 0.46 grams (adjusted for use of monohydrate)
- **Ice water**: 10 mL
- **Sodium bicarbonate solution**: 4 mL
- **Distilled water**: 4 mL
- **Anhydrous sodium sulfate**: A small amount for drying
### Equipment Needed:
- Reaction flask (100 mL capacity)
- Reflux condenser
- Separatory funnel
- Ice bath
- Fume hood
- Simple distillation setup for solvent evaporation
### Detailed Synthesis Procedure:
#### Step 1: Methylenation of Catechol
1. **Initial Setup**:
- In a 100 mL reaction flask equipped with a stirrer, add 20 mL of dichloromethane.
- Dissolve 0.36 grams of catechol and 0.46 grams of PTSA monohydrate in the flask.
2. **Addition of Formaldehyde**:
- Slowly add approximately 0.4 mL of 37% aqueous formaldehyde solution to the flask containing the catechol and PTSA mixture.
- Stir the mixture at room temperature for 1-2 hours to ensure complete methylenation.
#### Step 2: Preparation of Mixed Anhydride and Acylation
3. **Addition of Propionic Acid**:
- To the same reaction flask, add approximately 1.1 mL of propionic acid.
4. **Formation of Mixed Anhydride**:
- Slowly add approximately 1.1 mL of acetic anhydride to the flask.
- Stir the mixture at room temperature for about 30 minutes to allow the formation of the mixed anhydride (propionyl acetate).
5. **Acylation with Zinc Chloride**:
- Cool the entire reaction mixture in an ice bath to 0°C.
- Gradually add 0.76 grams of zinc chloride to the cooled reaction mixture.
- Allow the mixture to warm to room temperature while stirring.
- Continue stirring at room temperature for 4-5 hours.
#### Step 3: Workup and Purification
6. **Quenching the Reaction**:
- Carefully add 10 mL of ice water to the reaction flask to quench the reaction.
7. **Extraction**:
- Transfer the quenched mixture to a small separatory funnel.
- Extract the reaction mixture with 20 mL of dichloromethane in three portions (about 6-7 mL each), vigorously shaking and venting the funnel regularly to manage pressure.
- Collect the organic layer after each extraction.
8. **Neutralization and Washing**:
- Wash the combined organic layer in the separatory funnel with 4 mL of sodium bicarbonate solution, then with 4 mL of distilled water, gently shaking and venting as needed.
9. **Drying the Organic Layer**:
- Dry the organic extracts over a small amount of anhydrous sodium sulfate, then filter out the drying agent.
10. **Solvent Removal**:
- Allow the dichloromethane to evaporate naturally in a well-ventilated area or use a gentle heat source not exceeding 35°C.