How's such plan:
In nitrogen atmosphere, 3mmol n-BuLi,3mmol HMDS and 3ml DMF as solvent are added in reacting vessel. minutes later, 1mmol lanthanum chloride adds. Minutes later again, LaHMDS3 prepared.
Thank for everyone's supports.
To synthesize LaHMDS (Lithium bis(trimethylsilyl)amide), which is a strong base used in organic chemistry, you typically follow these steps in a laboratory setting:
1. **Precautions**: Work in a well-ventilated fume hood due to the reactive nature of the reagents and products.
2. **Materials Needed**:
- Trimethylsilyl chloride (Me3SiCl)
- Lithium metal (Li)
- Anhydrous tetrahydrofuran (THF)
- Argon or nitrogen gas source
- Diethyl ether (Et2O)
- Appropriate safety equipment (gloves, goggles, etc.)
3. **Procedure**:
a. **Preparation of Lithium Bis(trimethylsilyl)amide (LaHMDS)**:
- Start with dry THF in a reaction vessel under an inert atmosphere (argon or nitrogen).
- Add lithium metal to THF under stirring. Caution: This reaction can be vigorous due to the formation of lithium alkoxides; proceed slowly and monitor temperature.
- Once the lithium has dissolved, add trimethylsilyl chloride (Me3SiCl) dropwise. This forms lithium trimethylsilylamide (LiHMDS).
- Continue stirring and cooling the reaction mixture.
- After completion, add diethyl ether to the reaction mixture to precipitate LaHMDS.
- Filter the precipitate, which is LaHMDS, and wash it with cold diethyl ether to remove any impurities.
4. **Safety Notes**:
- Lithium metal reacts violently with water and alcohols, producing flammable hydrogen gas.
- Trimethylsilyl chloride is corrosive and should be handled with care.
- Work under an inert atmosphere to avoid reactions with moisture and oxygen.
5. **Storage**: Store LaHMDS under anhydrous conditions in an inert atmosphere to prevent decomposition.
This synthesis procedure should be performed by individuals trained in handling reactive chemicals and under appropriate safety protocols.