Triphenylsulfonium tetrafluoroborate

Triphenylsulfonium tetrafluoroborate [(C6Hs)3 S" BF4 ] is used instead of diphenyl iodonium chloride to give phenyl radical as the initiating species. Potassium [tris(oxalato) cobaltate) (III)] with diphenyl iodonium chloride also has been used as the photoinitiator of acryl-... 

Diphenylsulfonium cyciopropanide has been generated irreversibly Method A, by reaction of triphenylsulfonium tetrafluoroborate with cyclopropyllithium in tetrahydrofuran at — 78°C 61,65 or Method B, by treatment of cyclopropyldiphenylsulfonium tetrafluoroborate with sodium methylsulfinylmethanide in 1,2-dimethoxyethane at —40°C.57,65 However, reversible formation from cyclopropyldiphenylsulfonium tetrafluoroborate with Method C, powdered potassium hydroxide in dimethyl sulfoxide at + 25 °C, is easier to perform and gives higher yields of cyclobutanones l.62 A large-scale preparation of cyclopropyldiphenylsulfonium tetrafluoroborate has been reported.65,66... 

The UV sensitivity of the polyphthalaldehyde-onium salt system is dependent on the concentration and structure of the onium salts. At 10 wt% loading the sensitivity to narrow band width 254 nm radiation is 1-7 mJ/cm2 and is insensitive to the structure of the salts. However, at 2 wt% loading of triphenylsulfonium or diphenyliodonium hexafluoroarsenates or -hexyloxybenzenediazonium tetrafluoroborate much higher doses are required to achieve self-development and the sensitivity decreases with the salt structures in the sequence listed. 

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