methyllithium

Methyllithium is an organometallic compound with the chemical formula CH3Li. It is a strong base and a highly reactive nucleophile, commonly used in organic synthesis. It is typically prepared by reacting methyl halides, such as methyl chloride or methyl bromide, with lithium metal in an inert solvent like diethyl ether or tetrahydrofuran.

Methyllithium is a colorless solid but is usually handled as a solution in organic solvents due to its high reactivity. It is pyrophoric, meaning it can ignite spontaneously in air, and is also sensitive to moisture, reacting vigorously with water. For these reasons, it must be handled under an inert atmosphere, such as nitrogen or argon.

The primary applications of methyllithium in organic chemistry involve its use as a reagent for the formation of carbon-carbon bonds. It readily reacts with carbonyl compounds, such as aldehydes and ketones, to form alcohols. It can also react with epoxides, esters, and nitriles. Due to its strong basicity, it is employed in deprotonation reactions to generate carbanions. Methyllithium is also used as a precursor in the synthesis of other organometallic reagents. Safety precautions are paramount when working with methyllithium due to its hazardous nature.