EPR STUDIES ON H-ABSTRACTION FROM SILICON BY MAGIC BLUE - THE F,SI-NITROXIDES

The H-abstraction from benzyl silicanes (3-6), alkoxy silicanes (7-18) , phenyl alkoxy silicanes (19-22), and polybenzylsiloxane (23) by ''ma gic blue'' solution (in F113, CClF2-CCl2F) containing the H-abstractin g agent [H(CF2)(4)]2NO. (1) and spin trap H(CF2)(4)NO (2) was studied by EPR detection of the F, Si-nitroxides (a total of 24 from 21 silico n substrates) generated in the reactions. From the EPR spectra of the nitroxides, we have gained information about the position of H-abstrac tion, the subsequent radical steps after the H-abstraction, as well as the structures of the transient radical intermediates. This technique may serve as a new method for making multi- and polynitroxides under very mild conditions.