Methylmagnesium chloride is an

organometallic Organometallic chemistry is the study of organometallic compounds, chemical compounds containing at least one chemical bond between a carbon atom of an organic molecule and a metal, including alkali, alkaline earth, and transition metals, and so ...

compound with the general formula . This highly flammable, colorless, and moisture sensitive compound is the simplest

Grignard reagent Grignard reagents or Grignard compounds are chemical compounds with the general formula , where X is a halogen and R is an organic group, normally an alkyl or aryl. Two typical examples are methylmagnesium chloride and phenylmagnesium bromi ...

and is commercially available, usually as a solution in

tetrahydrofuran Tetrahydrofuran (THF), or oxolane, is an organic compound with the formula (CH2)4O. The compound is classified as heterocyclic compound, specifically a cyclic ether. It is a colorless, water- miscible organic liquid with low viscosity. It is ...

Synthesis and reactions

Relative to the more commonly encountered methylmagnesium bromide and methylmagnesium iodide, methylmagnesium chloride offers the advantages of low equivalent weight and low cost. It is prepared by the reaction of

methyl chloride Chloromethane, also called methyl chloride, Refrigerant-40, R-40 or HCC 40, is an organic compound with the chemical formula . One of the haloalkanes, it is a colorless, sweet-smelling, flammable gas. Methyl chloride is a crucial reagent in indus ...

and magnesium in

ethyl ether Diethyl ether, or simply ether, is an organic compound with the chemical formula , sometimes abbreviated as . It is a colourless, highly volatile, sweet-smelling ("ethereal odour"), extremely flammable liquid. It belongs to the ether class of o ...

. left, Structure of , which is representative of the species in donor solvents. As with most Grignard reagents, methylmagnesium chloride is highly solvated by

ether In organic chemistry, ethers are a class of compounds that contain an ether group, a single oxygen atom bonded to two separate carbon atoms, each part of an organyl group (e.g., alkyl or aryl). They have the general formula , where R and R� ...

solvents via

coordination Coordination may refer to: * Coordination (linguistics), a compound grammatical construction * Coordination complex, consisting of a central atom or ion and a surrounding array of bound molecules or ions ** A chemical reaction to form a coordinati ...

from two oxygen atoms to give a tetrahedrally bonded magnesium center. Like

methyllithium Methyllithium is the simplest organolithium reagent, with the empirical formula LiCH3. This s-block organometallic compound adopts an oligomeric structure both in solution and in the solid state. This highly reactive compound, invariably used i ...

, it is the synthetic equivalent to the

methyl In organic chemistry, a methyl group is an alkyl derived from methane, containing one carbon atom bonded to three hydrogen atoms, having chemical formula (whereas normal methane has the formula ). In formulas, the group is often abbreviated as ...

carbanion

synthon In retrosynthetic analysis, a synthon is a hypothetical unit within a target molecule that represents a potential starting reagent in the retroactive synthesis of that target molecule. The term was coined in 1967 by E. J. Corey. He noted in 1988 ...

. It reacts with water,

alcohols In chemistry, an alcohol (), is a type of organic compound that carries at least one hydroxyl () functional group bound to a Saturated and unsaturated compounds, saturated carbon atom. Alcohols range from the simple, like methanol and ethanol ...

and other

protic In chemistry, a protic solvent is a solvent that has a hydrogen atom bound to an oxygen (as in a hydroxyl group ), a nitrogen (as in an amine group or ), or fluoride (as in hydrogen fluoride). In general terms, any solvent that contains a labile ...

reagents to give methane, e.g.,: : When treated with

dioxane Dioxane may refer to the following chemical compounds: * 1,2-dioxane * 1,3-dioxane * 1,4-dioxane {{Authority control ...

, ether solutions of methylmagnesium chloride reacts to give the insoluble

coordination polymer Coordination may refer to: * Coordination (linguistics), a compound grammatical construction * Coordination complex, consisting of a central atom or ion and a surrounding array of bound molecules or ions ** A chemical reaction to form a coordinat ...

with the formula . Remaining in the solution is the dioxane adduct of

dimethylmagnesium Dimethylmagnesium is an organomagnesium compound with the chemical formula . It is a white pyrophoric solid. Dimethylmagnesium is used in the synthesis of organometallic compounds. Preparation Like other dialkylmagnesium compounds, dimethylmagne ...

. This conversion exploits the

Schlenk equilibrium The Schlenk equilibrium, named after its discoverer Wilhelm Schlenk, is a chemical equilibrium taking place in solutions of Grignard reagents and Hauser bases :2 RMgX MgX2 + MgR2 The process described is an equilibrium between two equivalents o ...

, which is driven to the right by the precipitation of the magnesium halide: :

References

Organomagnesium compounds Methylating agents Methyl complexes

Synthesis and reactions

See also

Further reading

References