THE 'trisyl' compounds TsiSiPh,F and TsiSiPh,I [where 'trisyl' refers to the (Me,Si),C group, symbolized by Tsi] undgrgo unusual reactions on pyrolysis, the former by a molecular elimination and the latter apparently by a free- radical process.lY2 It was thus of interest to see whether UV irradiation would initiate reactions of these compounds, and we find that while the fluoride is unaffected by irradi- ation in MeOH (as is the corresponding bromide)] novel reactions of the iodide ...