An electron spin resonance study of some silicon-centred free radicals with a tris(trimethylsilyl)methyl substituent

• Published in: Journal of organometallic chemistry Vol. 258; no. 3; pp. 271 - 275
• Main Authors: Al-wassil, Abdulaziz I., Eaborn, Colin, Hudson, Andrew, Jackson, Richard A.
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 01.01.1983; Elsevier Science
• Subjects: Atomic and molecular physics; Electron resonance and relaxation; Exact sciences and technology; Molecular properties and interactions with photons; Physics; Chemical rearrangement; EPR parameter; Photolysis; Organic free radical; Saturated aliphatic compound; Benzenic compound; Organic silane; EPR spectrum; Experimental study; Organic compounds
• ISSN: 0022-328X; 1872-8561
• DOI: 10.1016/S0022-328X(00)99271-4

Silicon-centred radicals with one bulky trisyl (  tris(trimethylsilyl)methyl  Tsi) substituent and all six combinations of hydrogen, methyl, and phenyl as the other two substituents have been formed by hydrogen abstraction from the corresponding silanes. Coupling constants are in the expected ranges, and no evidence for radical rearrangements was obtained. TsiSiH(OMe) 2 gives a mixture of TsiSi(OMe) 2 and TsiSiH(OMe)OCH 2·radicals. The ESR spectra were obscured by the presence of persistent radicals, but the signals+ of these were selectively removed by the technique of using intermittent UV light (3–5 Hz) to form the radicals, inverting the phase of the ESR spectrometer output each time the UV beam was interrupted or restored, and employing a relatively long time constant of 1–2 seconds.