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Methylmagnesium chloride

Methylmagnesium chloride
Names
IUPAC name
chlorido(methyl)magnesium
Other names
(chloromagnesio)methane
Identifiers
3D model (JSmol)
ChEBI
ChemSpider
ECHA InfoCard 100.010.573 Edit this at Wikidata
EC Number
  • 211-629-7
UNII
  • InChI=1S/CH3.ClH.Mg/h1H3;1H;/q;;+1/p-1 checkY
    Key: RQNMYNYHBQQZSP-UHFFFAOYSA-M checkY
  • InChI=1/CH3.ClH.Mg/h1H3;1H;/q;;+1/p-1/rCH3Mg.ClH/c1-2;/h1H3;1H/q+1;/p-1
    Key: RQNMYNYHBQQZSP-OWCPXFRBAR
  • [Cl-].[Mg+]C
Properties
CH3MgCl
Molar mass 74.79 g/mol
Appearance colorless solid
Reacts with water
Solubility soluble in diethyl ether and THF
Hazards
Occupational safety and health (OHS/OSH):
Main hazards
 Flammable, Reacts with water
GHS labelling:
GHS02: FlammableGHS05: Corrosive
Danger
H225, H250, H260, H314
P210, P222, P223, P231+P232, P233, P240, P241, P242, P243, P260, P264, P280, P301+P330+P331, P302+P334, P303+P361+P353, P304+P340, P305+P351+P338, P310, P321, P335+P334, P363, P370+P378, P402+P404, P403+P235, P405, P422, P501
NFPA 704 (fire diamond)
NFPA 704 four-colored diamondHealth 3: Short exposure could cause serious temporary or residual injury. E.g. chlorine gasFlammability 3: Liquids and solids that can be ignited under almost all ambient temperature conditions. Flash point between 23 and 38 °C (73 and 100 °F). E.g. gasolineInstability 2: Undergoes violent chemical change at elevated temperatures and pressures, reacts violently with water, or may form explosive mixtures with water. E.g. white phosphorusSpecial hazard W: Reacts with water in an unusual or dangerous manner. E.g. sodium, sulfuric acid
3
3
2
W
Flash point −17 °C (1 °F; 256 K)
Related compounds
Related compounds
 Phenylmagnesium bromide, Dibutylmagnesium
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
☒N verify (what is checkY☒N ?)

Methylmagnesium chloride is an organometallic compound with the general formula CH3MgCl. This highly flammable, colorless, and moisture sensitive material is the simplest Grignard reagent and is commercially available, usually as a solution in tetrahydrofuran.

Synthesis and reactions

Relative to the more commonly encountered methylmagnesium bromide[1] and methylmagnesium iodide, methylmagnesium chloride offers the advantages of low equivalent weight and low cost. It is prepared by the reaction of methyl chloride and magnesium in ethyl ether.[2]

Structure of CH3MgCl(thf)2, which is representative of the species in donor solvents.

As with most Grignard reagents, methylmagnesium chloride is highly solvated by ether solvents via coordination from two oxygen atoms to give a tetrahedrally bonded magnesium center.

Like methyllithium, it is the synthetic equivalent to the methyl carbanion synthon. It reacts with water and other protic reagents to give methane, e.g.,:

CH3MgCl + ROH → CH4 + MgCl(OR)

When treated with dioxane, ether solutions of methylmagnesium chloride reacts to give the insoluble coordination polymer with the formula MgCl2(dioxane)2. Remaining in the solution is the dioxane adduct of dimethylmagnesium. This conversion exploits the Schlenk equilibrium, which is driven to the right by the precipitation of the magnesium halide:[3]

2 CH3MgCl + 2 dioxane → (CH3)2Mg + MgCl2(dioxane)2

See also

Further reading

References

  1. ^ Raymond Paul; Olivier Riobé; Michel Maumy (1976). "(E)-4-Hexen-1-ol". Org. Synth. 55: 62. doi:10.15227/orgsyn.055.0062.
  2. ^ E. R. Coburn (1947). "3-Penten-2-ol". Org. Synth. 27: 65. doi:10.15227/orgsyn.027.0065.
  3. ^ Fischer, Reinald; Görls, Helmar; Meisinger, Philippe R.; Suxdorf, Regina; Westerhausen, Matthias (2019). "Structure–Solubility Relationship of 1,4‐Dioxane Complexes of Di(hydrocarbyl)magnesium". Chemistry – A European Journal. 25 (55): 12830–12841. doi:10.1002/chem.201903120. PMC 7027550. PMID 31328293.
Quelle: https://en.wikipedia.org/wiki/Methylmagnesium_chloride