Iodomethane
General
Systematic name	Iodomethane
Other names	Methyl iodide
Molecular formula	CH3I
SMILES	?
Molar mass	141.94 g/mol
Appearance	clear colourless liquid
CAS number	[74-88-4]
Properties
Density and phase	2.28 g/cm3, liquid
Solubility in water	Slightly soluble
In ethanol, ether In benzene	Fully miscible Soluble
Melting point	-66.5 °C (206.7 K)
Boiling point	42.4 °C (315.6 K)
Viscosity	? cP at ? °C
Structure
Molecular shape	Tetrahedral
Dipole moment	1.59 D (gas)
Hazards
MSDS	External MSDS
Main hazards	Toxic, poss. carcinogen
R/S statement	R: 21-23/25-37/38-40 S: 36/37-38-45
RTECS number	PA9450000
Supplementary data page
Structure & properties	n, εr, etc.
Thermodynamic data	Phase behaviour Solid, liquid, gas
Spectral data	UV, IR, NMR, MS
Related compounds
Related alkyl iodides Other methyl halides	Iodoethane
Other methyl halides	Bromomethane Chloromethane Fluoromethane
Except where noted otherwise, data are given for materials in their standard state (at 25°C, 100 kPa) Infobox disclaimer and references

Iodomethane, commonly called methyl iodide, is a dense volatile liquid. It is clear and colourless, though it is light sensitive and may develop a purplish tinge caused by iodine, thus it is usually stabilised by storage over copper metal. Methyl iodide is widely used in organic synthesis to deliver a methyl group into a structure, a process called methylation, usually via S_N2 substitution. IUPAC nomenclature is a systematic way of naming organic chemical compounds as recommended by the International Union of Pure and Applied Chemistry (IUPAC). ... A chemical formula (also called molecular formula) is a concise way of expressing information about the atoms that constitute a particular chemical compound. ... The simplified molecular input line entry specification or SMILES is a specification for unambiguously describing the structure of chemical molecules using short ASCII alpha-numeric strings. ... Molar mass is the mass of one mole of an element or chemical compound. ... CAS registry numbers are unique numerical identifiers for chemical compounds, polymers, biological sequences, mixtures and alloys. ... Density (symbol: ρ - Greek: rho) is a measure of mass per unit of volume. ... In the physical sciences, a phase is a set of states of a macroscopic physical system that have relatively uniform chemical composition and physical properties (i. ... A substance is soluble in a fluid if it dissolves in the fluid. ... Water is in dynamic equilibrium between the liquid and solid states at standard temperature and pressure. ... Ethanol, also known as ethyl alcohol or grain alcohol, is a flammable, colorless chemical compound, one of the alcohols that is most often found in alcoholic beverages. ... Diethyl ether, also known as ether and ethoxyethane, is a clear, colorless, and highly flammable liquid with a low boiling point and a typical smell. ... Benzene, C6H6, PhH, or benzol is a colorless and flammable liquid with a pleasant, sweet smell. ... The melting point of a solid is the temperature at which it changes state from solid to liquid. ... The boiling point of a substance is the temperature at which it can change state from a liquid to a gas throughout the bulk of the liquid. ... The Pitch Drop Experiment at the University of Queensland. ... The poise (P) is the cgs unit of viscosity, 1 P = 1 g·cm-1·s-1 The SI analog is 1 pascal second (Pa·s) = 1 kg·m-1·s-1 = 10 P. It is named after Jean Louis Marie Poiseuille. ... In chemistry, hybridisation is the mixing of atomic orbitals belonging to a same electron shell to form new orbitals suitable for the qualitative description of atomic bonding properties. ... A dipole (Greek: dyo = two and polos = pivot) is a pair of electric charges or magnetic poles of equal magnitude but opposite polarity (opposite electronic charges), separated by some (usually small) distance. ... The debye (symbol: D) is a derived CGS unit of electrical dipole moment. ... A material safety data sheet or MSDS is a form containing data regarding the properties of a particular substance. ... Worker safety and health is the prevention and reduction of the number of occupational safety and health hazards at the places of employment, providing safe and healthful working conditions. ... Risk and Safety Statements, also known as R/S statements, R/S numbers, R/S phrases, and R/S sentences, is a system of hazard codes and phrases for labeling dangerous chemicals and compounds. ... RTECS, also known as Registry of Toxic Effects of Chemical Substances, is a database of toxicity information compiled from the open scientific literature that is available for charge. ... The parameter used to describe the interaction of electromagnetic radiation with matter is the complex index of refraction, , which is a combination of a real part and an imaginary part. ... The dielectric constant εr (represented as or K in some cases) is defined as the ratio: where εs is the static permittivity of the material in question, and ε0 is the vacuum permittivity. ... Ultraviolet-Visible spectroscopy or Ultraviolet-Visible spectrophotometry (UV/ VIS) involves the spectroscopy of photons (spectrophotometry). ... IR spectrum of a thin film of liquid ethanol. ... Nuclear Magnetic Resonance Spectroscopy is the name given to the technique which exploits the magnetic properties of nuclei. ... Mass spectrometry is a technique for separating ions by their mass-to-charge (m/z) ratios. ... In chemistry, an alkyl halide is an organic molecule of the form R_X, where X is a halide and R contains a carbon atom bonded to other functional groups or hydrogens. ... The chemical compound bromomethane is an organic halogen compound with formula BrCH3. ... Chloromethane or Methyl chloride is a chemical compound once widely used as a refrigerant. ... Fluoromethane (also known as methyl fluoride, Freon 41, or Fluoromethane-d3) is a toxic, liquefiable, and flammable gas at standard temperature and pressure. ... In chemistry, the standard state of a material is its state at 1 bar (100. ... Density (symbol: ρ - Greek: rho) is a measure of mass per unit of volume. ... The vapor pressure is the pressure (if the vapor is mixed with other gases, the partial pressure) of a vapor. ... General Name, Symbol, Number copper, Cu, 29 Chemical series transition metals Group, Period, Block 11, 4, d Appearance copper, metallic Atomic mass 63. ... Organic synthesis is the construction of organic molecules via chemical processes. ... In chemistry a methyl-group is a hydrophobic Alkyl functional group which is derived from methane (CH4). ... Methylation refers to the replacement of a hydrogen atom (H) with a methyl group (CH3), regardless of the substrate. ... In chemistry, nucleophilic substitution is a type of chemical reaction in which one nucleophile electron donor replaces another as a covalent substitute of some atom. ...

Chemical properties

Methyl iodide is an excellent reagent for S_N2 substitution reactions – it is sterically open for attack by nucleophiles, and it has an excellent leaving group (iodide), making it a reactive substrate for such reactions. For example, it can be used for the methylation of phenols or carboxylic acids: Steric effects are the interaction of molecules dictated by their shape and/or spatial relationships. ... In chemistry, a nucleophile (literally nucleus lover) is a reagent which is attracted to centres of positive charge. ... A leaving group is an atom or molecule that detaches from an organic molecule, which, after detachment, is called the residual or main part. ... An iodide ion is an iodine atom with charge -1. ... Phenol, also known under the old name carbolic acid, is a colorless crystalline solid with a typical sweet tarry odor. ... Structure of a carboxylic acid Carboxylic acids are organic acids characterized by the presence of a carboxyl group, which has the formula -C(=O)-OH, usually written as COOH. The salts and anions of carboxylic acids are called carboxylates generally. ...

In both of these example the base (K₂CO₃ or Li₂CO₃) removes the acidic proton to form an anion, which serves as the nucleophile in the S_N2 substitution. The common (Arrhenius) definition of a base is a chemical compound that either donates hydroxide ions or absorbs hydrogen ions when dissolved in water. ... Potassium carbonate is a white salt, soluble in water (insoluble in alcohol), which forms a strongly alkaline solution. ... Lithium salts are chemical salts of lithium used as mood stabilizing drugs, primarily in the treatment of bipolar disorder, depression, and mania; but also in treating schizophrenia. ...

The iodide is a soft leaving group, so that methylation tends to occur at the "softer" end of an ambident nucleophile- for example, reaction with thiocyanate ion favours attack at "soft" S rather than "hard" N, leading mainly to CH₃SCN rather than CH₃NCS. This is valuable in the methylation of stabilized enolates (such as those from 1,3-dicarbonyl compounds), where alkylation of an enolate may occur on the harder oxygen atom rather than the (usually desired) carbon atom. With methyl iodide, C-alkylation nearly always predominates. The HSAB concept, also known as HSAB theory, is widely used in chemistry for explaining stability of compounds, reaction paths etc. ... In chemistry, a nucleophile (literally nucleus lover) is a reagent which is attracted to centres of positive charge. ... Thiocyanate (also known as sulphocyanate or thiocyanide) is a functional group consisting of sulfur, carbon, and nitrogen: N-(triple bond)-C-S- It has a charge of 1-. It is analogous to the cyanate ion, with oxygen replaced by sulfur. ... General Name, Symbol, Number sulfur, S, 16 Chemical series nonmetals Group, Period, Block 16, 3, p Appearance lemon yellow Atomic mass 32. ... General Name, Symbol, Number nitrogen, N, 7 Chemical series nonmetals Group, Period, Block 15, 2, p Appearance colorless Atomic mass 14. ... Methylation refers to the replacement of a hydrogen atom (H) with a methyl group (CH3), regardless of the substrate. ... Enol (or, more officially, but less commonly: alkenol) is an alkene with hydroxyl group on one of the carbon atoms of the double bond. ... General Name, Symbol, Number oxygen, O, 8 Chemical series nonmetals Group, Period, Block 16, 2, p Appearance colorless Atomic mass 15. ...

Preparation

Iodomethane is usually prepared in the laboratory by the exothermic reaction that occurs when iodine is added to a mixture of methanol with red phosphorus: In chemistry, an exothermic reaction is one that releases heat. ... General Name, Symbol, Number iodine, I, 53 Chemical series halogens Group, Period, Block 17, 5, p Appearance violet-dark gray, lustrous Atomic mass 126. ... Methanol, also known as methyl alcohol or wood alcohol, is a chemical compound with chemical formula CH3OH. It is the simplest alcohol, and is a light, volatile, colourless, flammable, poisonous liquid that is used as an antifreeze, solvent, fuel, and as a denaturant for ethyl alcohol. ... This article is about the chemical element. ...

20 CH₃OH + P₄ + 10 I₂ → 20 CH₃I + 4 H₃PO₄ + 4 H₂O Methanol, also known as methyl alcohol or wood alcohol, is a chemical compound with chemical formula CH3OH. It is the simplest alcohol, and is a light, volatile, colourless, flammable, poisonous liquid that is used as an antifreeze, solvent, fuel, and as a denaturant for ethyl alcohol. ... This article is about the chemical element. ... General Name, Symbol, Number iodine, I, 53 Chemical series halogens Group, Period, Block 17, 5, p Appearance violet-dark gray, lustrous Atomic mass 126. ... Phosphoric acid, also known as orthophosphoric acid or phosphoric(V) acid, is a weak mineral acid with the chemical formula H3PO4. ... Water is in dynamic equilibrium between the liquid and solid states at standard temperature and pressure. ...

The CH₃I can easily be distilled from the mixture, and purified by washing with Na₂S₂O₃ (to remove iodine) and then water, aq. Na₂CO₃ and water. It is then dried over CaCl₂ and distilled. Another purification method involves percolation of the product through silica gel or activated alumina. Sodium thiosulfate (Na2S2O3) is a colorless crystalline compound that is more familiar as the pentahydrate, Na2S2O3 · 5H2O, an efflorescent, monoclinic crystalline substance also called sodium hyposulfite or “hypo. ... Drinking water This article focuses on water as we experience it every day. ... Sodium carbonate or soda ash, Na2CO3, is a sodium salt of carbonic acid. ... Calcium chloride is a chemical compound of calcium and chlorine. ... Some examples of silica gel sachets Silica gel is a granular, porous form of silica made synthetically from sodium silicate. ... Aluminium oxide (or aluminum oxide) (Al2O3) is a chemical compound of aluminium and oxygen. ...

An alternative preparation involves the addition of dimethyl sulfate to a stirred suspension of calcium carbonate in aqueous potassium iodide: Dimethyl sulfate has chemical formula (CH3)2SO4. ... Calcium carbonate is a chemical compound, with chemical formula CaCO3. ... Potassium iodide is a white crystalline salt with chemical formula KI, used in photography and radiation treatment. ...

(CH₃O)₂SO₂ + KI → CH₃I + CH₃OSO₂OK Dimethyl sulfate has chemical formula (CH3)2SO4. ... Potassium iodide is a white crystalline salt with chemical formula KI, used in photography and radiation treatment. ...

Both methods of preparation give high chemical yields of methyl iodide. Yield in chemistry, also known as chemical yield and reaction yield, is the amount of product obtained in a chemical reaction. ...

Uses

Suppliers/Manufacturers

References

1. J. March, Advanced Organic Chemistry, 4th ed., p. 723, Wiley, New York, 1992.
2. G. A. Sulikowski, M. M. Sulikowski, in Handbook of Reagents for Organic Synthesis, Volume 1: Reagents, Auxiliaries and Catalysts for C-C Bond Formation, (R. M. Coates, S. E. Denmark, eds.), pp. 423-426, Wiley, New York, 1999.