Dimethylmagnesium is an
organomagnesium compound Magnesium anthracenide with three thf ligands. Group 2 organometallic chemistry refers to the chemistry of compounds containing carbon bonded to any group 2 element. By far the most common group 2 organometallic compounds are the magnesium-containi ...
. It is a white
pyrophoric
A substance is pyrophoric (from grc-gre, πυροφόρος, , 'fire-bearing') if it ignites spontaneously in air at or below (for gases) or within 5 minutes after coming into contact with air (for liquids and solids). Examples are organolit ...
solid. Dimethylmagnesium is used in the synthesis of organometallic compounds.
Preparation
Like other dialkylmagnesium compounds, dimethylmagnesium is prepared by adding
dioxane
1,4-Dioxane () is a heterocyclic organic compound, classified as an ether. It is a colorless liquid with a faint sweet odor similar to that of diethyl ether. The compound is often called simply dioxane because the other dioxane isomers ( 1,2- ...
to a solution of
methylmagnesium halide:
[
:2 CH3MgX + 2 dioxane (CH3)2Mg + MgX2(μ-dioxane)2↓
In such procedures, the dimethylmagnesium exists as the ether adduct, not the polymer.][
Addition of ]1,4-dioxane
1,4-Dioxane () is a heterocyclic organic compound, classified as an ether. It is a colorless liquid with a faint sweet odor similar to that of diethyl ether. The compound is often called simply dioxane because the other dioxane isomers ( 1 ...
causes precipitation of solid MgX2(μ-dioxane)2, a coordination polymer.Schlenk equilibrium Schlenk can refer to:
People
* Wilhelm Schlenk (1879-1943), German chemist
In chemistry
* Schlenk flask
* Schlenk line
The Schlenk line (also vacuum gas manifold) is a commonly used chemistry apparatus developed by Wilhelm Schlenk. It consists ...
toward (CH3)2Mg. Related methods have been applied to other dialkylmagnesium compounds.dimethylmercury
Dimethylmercury (( C H3)2 Hg) is an extremely toxic organomercury compound. A highly volatile, reactive, flammable, and colorless liquid, dimethylmercury is one of the strongest known neurotoxins, with a quantity of less than 0.1 mL capable of in ...
and magnesium.
Properties
The structure of this compound has been determined by X-ray crystallography
X-ray crystallography is the experimental science determining the atomic and molecular structure of a crystal, in which the crystalline structure causes a beam of incident X-rays to diffract into many specific directions. By measuring the angles ...
. The material is a polymer with the same connectivity as silicon disulfide, featuring tetrahedral magnesium centres, each surrounded by bridging methyl groups. The Mg-C distances are 224 pm. Dimethylberyllium adopts the same structure.
References
{{Reflist
Organomagnesium compounds