Английская Википедия:Dimethylmagnesium
Dimethylmagnesium is an organomagnesium compound. It is a white pyrophoric solid.[1][2] Dimethylmagnesium is used in the synthesis of organometallic compounds.
Preparation
Like other dialkylmagnesium compounds, dimethylmagnesium is prepared by adding dioxane to a solution of methylmagnesium halide:[3]
- 2 CH3MgX + 2 dioxane Шаблон:Eqm (CH3)2Mg + MgX2(μ-dioxane)2↓
In such procedures, the dimethylmagnesium exists as the ether adduct, not the polymer.[4]
Addition of 1,4-dioxane causes precipitation of solid MgX2(μ-dioxane)2, a coordination polymer.[4] This precipitation drives the Schlenk equilibrium toward (CH3)2Mg. Related methods have been applied to other dialkylmagnesium compounds.[3]
Dimethylmagnesium can also be prepared by combining dimethylmercury and magnesium.[5][6]
Properties
The structure of this compound has been determined by X-ray crystallography. 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.[7] Dimethylberyllium adopts the same structure.[8]
References
