Thermal decomposition mechanism of allyltrichlorosilane and allyltrimethylsilane

Thermal decomposition of allyltrichlorosilane and allyltrimethylsilane at temperatures up to 1340 K were studied using flash pyrolysis coupled with molecular beam sampling vacuum ultraviolet single-photon ionization time-of-flight mass spectrometry (VUV-SPI-TOFMS). The initial reaction was homolysis the Si–C bond, producing •SiCl3 •C3H5 radicals. radical then underwent sequential Cl losses form :SiCl2, SiCl Si. C3H5 also secondary reactions, a series C3Hx species (m/z = 39–42), consistent previous studies. In allyltrimethylsilane, elimination forming Me2Si=CH2 + C3H6 bond ruptures Me3Si• Me2Si˙CH2CH=CH2 •CH3 identified as main initiation steps. HSiMe3 one products. observed reactions Possible thermal mechanism product proposed.