methyllithium

Methyllithium

English name: Methyllithium

CAS No.: 917-54-4

Packaging/Storage: 1. Packaged in 500ml bottles, 30L steel cylinders, or 300/500L storage tanks. 2. During use, this product should be isolated from air and moisture to the greatest extent possible, stored below 2~8°C, and used under the protection of nitrogen or argon. 3. Avoid high temperatures and impacts, do not expose to open flames, and must not come into contact with air and water. Store at low temperatures.

Methyllithium

CAS No.: 917-54-4

Molecular formula: CH₃Li

Molecular weight: 21.98

Basic Information

Appearance: Colorless or yellow transparent liquid

Density: 0.85g/ml (20°C)

Boiling point: 87~88°C (refers to the solvent, not the solute)

Flash point: -15°C

Concentration: 1.0M, 2.0M, 3.0M (diethoxymethane solution)

Properties

Reacts violently with water and air: It will react instantly with water or protic solvents containing active hydrogen to generate flammable methane gas. At the same time, it is extremely sensitive to air.

Flammable: Non-solvated solid methyllithium can spontaneously ignite in air. Even for solutions, they are extremely prone to catching fire once the solvent evaporates and dries out.

Stability: Needs to be stored and used at low temperatures.

Applications

1. Nucleophilic addition reaction: Constructing carbon-carbon bonds, which is the most widely used application of methyllithium, using the negative charge on its methyl group to attack electrophilic carbon atoms.

2. Metalation reaction: Methyllithium has strong basicity, and can be used to prepare other active organometallic reagents through lithium-halogen exchange or deprotonation reactions.

3. Used as a strong base: Although its basicity is slightly weaker than that of butyllithium, methyllithium can still be used as a strong base, especially in occasions where both its basicity and subsequent transformation potential are required.

4. Synthesis of important organometallic compounds: Methyllithium is an important raw material for synthesizing other organometallic reagents. For example: alkyl copper lithium (Gilman reagent): Reacts with cuprous halide (CuI) to generate dimethyl copper lithium ((CH₃)₂CuLi). The nucleophilicity of Gilman reagent is mild, and it is especially suitable for conjugate addition (1,4-addition) with alkyl halides or α,β-unsaturated ketones, which cannot be achieved directly by methyllithium.

Packaging/Storage

1. Packaged in 500ml bottles, 30L steel cylinders, or 300/500L storage tanks.

2. During use, this product should be isolated from air and moisture to the greatest extent possible, stored below 2~8°C, and used under the protection of nitrogen or argon.

3. Avoid high temperatures and impacts, do not expose to open flames, and must not come into contact with air and water. Store at low temperatures.