Tetrahydrogen lithium aluminum and its participating reactions (2)

Three, examples

example 1

Make a reduction reaction involving LiAlH ₄ and AlCl ₃ :

Application process: Weigh LiAlH ₄ (5.

Note: A1H ₃ has great chemical activity and is extremely flammable.

3LiAlH ₄ +AlCl ₃ =4AlH ₃ +3LiCl

The resulting AlH ₃ forms a complex with ethers, such as

AlH ₃ +(C ₂ H ₅ ) ₂ O=H ₃ Al.

The reaction to prepare AlH ₃ and the subsequent reduction reaction are generally carried out in ether solvents, such as diethyl ether , tetrahydrofuran , methyltetrahydrofuran , methyl tert-butyl ether and so on

Example 2

Do a LiAlH ₄ reduction ester reaction:

Dissolve 30g of the substrate in 500mL THF (1L single-neck bottle), add LiAlH ₄ at room temperature .

In addition to solving the above deficiencies, it is recommended to dissolve the product in THF when doing LiAlH ₄ reactions, especially for large-scale reactions, and then slowly drop them into the LiAlH ₄ THF solution, which is safer