In organic chemistry, a methiodide is a chemical derivative produced by the reaction of a compound with methyl iodide. Methiodides are often formed through the methylation of tertiary amines:
Whereas the parent amines are hydrophobic and often oily, methiodides, being salts, are somewhat hydrophilic and exhibit high melting points. Methiodides exhibit altered pharmacological properties as well.
Examples include:
Tertiary phosphines and phosphite esters also form methiodides.[2]