Monohalomethane

Structural formula
Name	Fluoromethane Methyl fluoride	Chloromethane Methyl chloride	Bromomethane Methyl bromide	Iodomethane Methyl iodide
Melting point	−137,8 °C [1]	−97,4 °C [2]	−93,7 °C [3]	−66 °C [4]
Boiling point	−78,4 °C [1]	−23,8 °C [2]	4,0 °C [3]	42 °C [4]
Space-filling model

The monohalomethanes are organic compounds in which a hydrogen atom in methane is replaced by a halogen. They belong to the haloalkanes or to the subgroup of halomethanes.

The four common ^[a] members are fluoromethane, chloromethane, bromomethane and iodomethane.

Historical name for this group is methyl halides; it's still widely used. The compounds of this class are often described as CH₃X or MeX (X - any halogen, Me - methyl group).

Related compounds

See also: Group 14 tetrahydride

There are analogs with more than one hydrogen atom in methane is replaced by a halogen:

• Dihalomethane, CH₂X₂, two hydrogen atoms replaced
• Trihalomethane, CHX₃, three hydrogen atoms replaced
• Tetrahalomethane, CX₄, all four hydrogen atoms replaced

Analogs with carbon atom replaced with a heavier group 14 element are also known:

• Monohalosilane, SiH₃X (with silicon, related to silane)
• Monohalogermane, GeH₃X (with germanium, related to germane)
• Monohalostannane, SnH₃X (with tin, related to stannane)

See also

• Methyl halide transferase – An enzyme producing some methyl halides

Notes

1. Highly radioactive CH₃At (methyl astatide) has been detected. ^[5] The known isotopes of even heavier group 17 element, tennessine, are too short-lived to allow for chemical experimentation.

References

1. Recordof Fluoromethane in the GESTIS Substance Database of the Institute for Occupational Safety and Health , accessed on 2020-02-29.
2. Recordof Chloromethane in the GESTIS Substance Database of the Institute for Occupational Safety and Health , accessed on 2020-02-29.
3. Recordof Bromomethane in the GESTIS Substance Database of the Institute for Occupational Safety and Health , accessed on 2020-02-29.
4. Recordof Iodomethane in the GESTIS Substance Database of the Institute for Occupational Safety and Health , accessed on 2020-02-29.
5. "Chemical Fact Sheet: Astatine". European Virtual Institute for Speciation Analysis (EVISA).