EtMgCl

EtMgCl, or ethylmagnesium chloride, is a Grignard reagent with the formula C2H5MgCl. It is widely used as a nucleophilic ethyl donor in organic synthesis. In typical preparation, ethylmagnesium chloride is formed by reacting ethyl halide (chloro- or bromoethyl compounds) with magnesium metal in a strictly anhydrous ether solvent, such as diethyl ether or THF. The reagents are highly moisture- and air-sensitive, and the solution often exists as solvent-coordinated aggregates.

EtMgCl is a highly reactive organomagnesium species that acts as both a nucleophile and a strong base in ether solutions. It adds to carbonyl compounds to form alcohols after aqueous workup: with formaldehyde it gives primary alcohols, while reactions with higher aldehydes and ketones yield secondary or tertiary alcohols bearing an ethyl substituent. It also reacts with carbon dioxide to give propionic acid after acidic workup. Reaction with epoxides affords alcohols with one-carbon chain extension. Like other Grignard reagents, EtMgCl quenches readily with water or alcohols to produce alkanes and magnesium salts, and therefore must be prepared and handled under strictly anhydrous, inert conditions.

Handling and safety considerations include storage under dry inert gas, protection from moisture and air, and the use of dry, oxygen-free solvents. ethers used as solvents are flammable and can form peroxides over time; appropriate precautions and ventilation are required in practical use.