VP (3,3,5-Trimethylcyclohexyl 3-pyridyl methylphosphonate), also known as EA-1511, is an extremely toxic organophosphate

nerve agent Nerve agents, sometimes also called nerve gases, are a class of organic chemistry, organic chemicals that disrupt the mechanisms by which nerves transfer messages to organs. The disruption is caused by the blocking of acetylcholinesterase (ACh ...

of the V-series. Agent VP belongs to a class of organophosphates known as 3-pyridyl phosphonates. These agents are extremely potent

acetylcholinesterase inhibitor Acetylcholinesterase inhibitors (AChEIs) also often called cholinesterase inhibitors, inhibit the enzyme acetylcholinesterase from breaking down the neurotransmitter acetylcholine into choline and acetate, thereby increasing both the level an ...

Synthesis

Methylphosphonic dichloride Methylphosphonyl dichloride (DC) or dichloro is an organophosphorus compound. It has commercial application in oligonucleotide synthesis, but is most notable as being a precursor to several chemical weapons agents. It is a white crystalline solid ...

and

triethylamine Triethylamine is the chemical compound with the formula N(CH2CH3)3, commonly abbreviated Et3N. Like triethanolamine and the tetraethylammonium ion, it is often abbreviated TEA. It is a colourless volatile liquid with a strong fishy odor remini ...

are dissolved in

benzene Benzene is an Organic compound, organic chemical compound with the Chemical formula#Molecular formula, molecular formula C6H6. The benzene molecule is composed of six carbon atoms joined in a planar hexagonal Ring (chemistry), ring with one hyd ...

3,3,5-Trimethylcyclohexanol 3,3,5-Trimethylcyclohexanol is a precursor to the vasodilator cyclandelate, the sunscreen component homosalate and the VP nerve agent. It can be synthesized by hydrogenation of isophorone. It has a mint flavour. See also * Cyclandelate * VP (ne ...

is then slowly added while stirring and cooling. The reaction temperature is maintained at 15 °C. The mixture is then heated to 40 °C for 1 hour. A benzene solution of 3,3,5-trimethylcyclohexyl methylphosphonochloridate is formed. Triethylamine is then added to reaction mixture and 3-pyridol is added slowly while stirring and cooling. The reaction temperature is maintained at 35 °C. The mixture is then stirred for 1 hour at room temperature. The mixture is washed with a

sodium hydroxide Sodium hydroxide, also known as lye and caustic soda, is an inorganic compound with the formula . It is a white solid ionic compound consisting of sodium cations and hydroxide anions . Sodium hydroxide is a highly corrosive base (chemistry), ...

solution and water. The solvent is then removed by

distillation Distillation, also classical distillation, is the process of separating the component substances of a liquid mixture of two or more chemically discrete substances; the separation process is realized by way of the selective boiling of the mixt ...

at reduced pressure to yield the final product. The resulting product can be converted to a quaternary salt by reacting with a

haloalkane The haloalkanes (also known as halogenoalkanes or alkyl halides) are alkanes containing one or more halogen substituents of hydrogen atom. They are a subset of the general class of halocarbons, although the distinction is not often made. Haloalka ...

, such as

methyl iodide Iodomethane, also called methyl iodide, and commonly abbreviated "MeI", is the chemical compound with the formula CH3I. It is a dense, colorless, volatile liquid. In terms of chemical structure, it is related to methane by replacement of one h ...

, to produce a water-soluble agent.

References

{{DEFAULTSORT:Trimethylcyclohexyl 3-pyridyl methylphosphonate, 3,3,5- V-series nerve agents Acetylcholinesterase inhibitors 3,3,5-Trimethylcyclohexyl esters 3-Pyridyl compounds Phosphonate esters