Description
Specifications Table
Product Name – Lithium bis(trimethylsilyl)amide, 1M solution in THF/Ethylbenzene, AcroSeal® Quantity/Pack Size – 100ML, 800ML Form – Liquid (solution) Grade – Synthesis grade Application – Strong base for deprotonation, enolate formation, and organolithium reactions
Product Overview
Lithium bis(trimethylsilyl)amide (LiHMDS) is a highly reactive, non-nucleophilic superbase supplied as a 1M solution in THF/ethylbenzene under the AcroSeal® system for enhanced stability and moisture protection. This organolithium reagent is widely recognized for its exceptional basicity, making it ideal for deprotonating weakly acidic compounds without competing nucleophilic side reactions. The THF/ethylbenzene solvent blend ensures optimal solubility and reactivity, while the AcroSeal® packaging prevents degradation from air or moisture exposure, maintaining reagent purity over extended storage periods. The solution’s controlled concentration eliminates the need for titration, providing consistent performance in sensitive synthetic applications. Its low nucleophilicity and high selectivity allow for precise enolate formation, metal-halogen exchange, and directed ortho-metalation reactions. The ethylbenzene co-solvent enhances thermal stability, reducing the risk of exothermic decomposition during handling. This reagent is particularly valuable in multi-step organic synthesis where reproducibility and yield are critical, offering a reliable alternative to traditional bases like n-butyllithium or sodium hydride.
FAQs
1. What precautions should be taken when handling this 1M LiHMDS solution?
This solution is highly air- and moisture-sensitive. Always work under an inert atmosphere (argon/nitrogen) using dry syringes or cannula techniques. Avoid skin contact and use in a well-ventilated fume hood due to the flammable solvent mixture.
2. Can this solution be used as a direct replacement for solid LiHMDS?
Yes, but adjust stoichiometry based on the 1M concentration. The solution offers easier handling than solid LiHMDS, which requires glove-box conditions. Reaction times may vary slightly due to the solvent system.
3. How does the THF/ethylbenzene solvent blend affect reactivity compared to pure THF?
The ethylbenzene co-solvent moderates the reactivity slightly, improving thermal stability while maintaining high basicity. It reduces the risk of violent exotherms during addition to substrates compared to pure THF solutions.
4. What is the typical shelf life of this AcroSeal®-packaged solution?
When stored unopened at room temperature under inert conditions, the solution remains stable for 12–18 months. Once opened, use within 3 months or re-seal under argon for extended storage.
5. Are there compatibility issues with glassware when using this reagent?
The solution is compatible with standard borosilicate glass, but prolonged contact with soda-lime glass may lead to leaching. For long reactions, use PTFE-lined or glass-lined equipment to prevent contamination.
