CAS Registry Number

CAS 78-50-2 — Trioctylphosphine oxide

Trioctylphosphine oxide (TOPO) is a phosphorus-based organophosphine oxide widely used as a ligand in semiconductor manufacturing, particularly in the synthesis of III-V and II-VI compounds via organometallic vapor phase epitaxy (OMVPE). It acts as a stabilizing agent, solvent, and phase-transfer catalyst in chemical processes. This clear, viscous liquid has a CAS number of 78-50-2, with the molecular formula [CH3(CH2)7]3PO and a molecular weight of 386.63. It should be stored at ambient conditions but handled with caution, as it carries a "Danger" signal word. Molekula supplies trioctylphosphine oxide from research to bulk quantities with full documentation and ISO 9001:2015 traceability.