Triphenyl phosphite ozonide

Triphenyl phosphite ozonide (TPPO) is a chemical compound with the formula PO₃(C₆H₅O)₃ that is used to generate singlet oxygen.^[1][2]

Triphenyl phosphite ozonide

Names
IUPAC name 4,4,4-triphenoxy-1,2,3,4λ5-trioxaphosphetane
Identifiers
CAS Number	29833-83-8 Y
3D model (JSmol)	Interactive image
Abbreviations	TPPO
ChemSpider	10450618
PubChem CID	12503112
InChI InChI=1S/C18H15O6P/c1-4-10-16(11-5-1)19-25(23-22-24-25,20-17-12-6-2-7-13-17)21-18-14-8-3-9-15-18/h1-15H Key: BVCCTQHXJQXLKM-UHFFFAOYSA-N
SMILES C1=CC=C(C=C1)OP2(OOO2)(OC3=CC=CC=C3)OC4=CC=CC=C4
Properties
Chemical formula	C18H15O6P
Molar mass	358.286 g·mol−1
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

When TPPO is mixed with amines, the ozonide breaks down into singlet oxygen and leaves behind triphenyl phosphite.^[2] Pyridine is the only known amine that can effectively cause the breakdown of TPPO while not quenching any of the produced oxygen.^[1][2]

Synthesis

Triphenyl phosphite ozonide is created by bubbling dry ozone through dichloromethane with triphenyl phosphite being added dropwise at -78 °C.^[2] If triphenyl phosphite is added in excess in the synthesis, TPPO can be reduced to triphenyl phosphite oxide, PO(C₆H₅O)_3, and oxygen gas.^[3]