Diisopropyl methylphosphonate (DIMP), also known as diisopropyl methane-phosphonate and phosphonic acid and methyl-bis-(1-methylethyl)ester, is a chemical by-product in the production of sarin gas when two equivalents of isopropyl alcohol react with methylphosphonyl difluoride instead of one.

[1] DIMP is a colorless liquid that has been shown to affect the hematological (blood forming) system in animals.

[4] DIMP is a chemical by-product resulted from the manufacture of sarin (GB).

[6] DIMP is not known to occur naturally in the environment.

[citation needed] DIMP can be prepared by a gradual addition of triisopropyl phosphite with methyl iodide, utilizing distillation technique.