Tris (trimethylsilyl)-2, 2, 2-trifluoroethoxysilane 6, tris (trimethylsilyl)-2-fluoroethoxysilane 7, and tris (trimethylsilyl)-2-chloroethoxysilane 8 were synthesized and characterized by 1H, 13C and 29Si NMR, IR spectroscopy, and EI and CI mass spectrometry. Thermodynamic considerations would suggest that, as a result of the driving force provided by the formation of a Si-F or Si-CI bond, the thermolyses of these compounds would lead to the formation of ...