PHOTOLYSIS OF SOME ORGANOSILYLENE PRECURSORS IN A MOLECULAR-BEAM

The condensed-phase organosilylene precursors PhMeSi(SiMe(3))(2) (1), PhSi(SiMe(3))(3) (2), and (Me(2)Si)(6) (3) were photolyzed in a molecu lar beam using a pulsed supersonic jet and mass spectrometric detectio n. Under similar to 10 ns pulsed UV illumination, we have found for th e gas-phase trisilane precursors 1 and 2 that one photon results in re moval of only one -SiMe(3) group. Even at the highest laser power dens ities used, there is no evidence of removal of a second -SiMe(3) to fo rm a silylene. On the other hand, a single photolysis photon was capab le of producing the silylene for the cyclohexasilane ring precursor, 3 .