Diethyl phosphite

Diethyl phosphite (CAS 762-04-9), also referred to commercially as diethyl phosphonate or DEP, is a reactive organophosphorus compound used as a chemical intermediate and functional additive.

Where is Diethyl phosphite used?

• Lubricants and metalworking fluids: extreme-pressure additive and antiwear agent that reduces metal surface degradation under high-load conditions
• Pharmaceuticals: key intermediate in the synthesis of active pharmaceutical ingredients, particularly antiviral and antiparasitic compounds
• Agrochemicals: precursor in the manufacture of organophosphate pesticides and herbicides
• Polymers and plastics: flame retardant additive and stabilizer
• It acts as a building block for synthesizing phosphorus-containing compounds.

Commercial specifications

• Drum and IBC quantities; bulk tanker supply available
• Technical grade standard, purity typically 98% or higher
• Pharmaceutical-intermediate grade with controlled impurity profiles from select manufacturers