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Mediyl Radical

In many gaseous state reactions of technological importance, short-lived intermediate molecules which are formed by die decomposition of reacting species play a significant role in die reaction kinetics. Thus reactions involving die mediane molecule, CH4, show die presence of a well-defined dissociation product, CH3, die mediyl radical, which has a finite lifetime as a separate entity and which plays an important part in a sequence or chain of chemical reactions. [Pg.42]

The product formed in second-highest yield, 1,1,1,2-tetramethyldi-silane, as well as methylsilane require transfer of a mediyl group for their formation. No neutral silicon species are known to abstract metliyl groups, but Lampe has found that cations of various kinds do abstract mediyl radicals and methide anions from methylsilanes (29-31),... [Pg.11]

Attempts to cyclize ethyl ( )-2-acetyl-2-methyl-6-bromo-4-hexenoate have been unsuccessful, with ediyl 2-melhyl-3-oxobutanoate isolated as the major product of die reaction (equation 52). Loss of butadiene, as required for this transformation, is clearly facilitated by the ability of a 3-keto ester stabilized (radical or anion) intermediate to serve as an effective leaving group in the reaction. Thus, cyclization of ( )-8-bromo-4-mediyl-6-octen-3-one proceeds smoothly to provide die expected caibocycle in 91% isolated yield (equation S3). [Pg.266]

FIpBc I61I4 Protective effect against degradation by y>radiation provided by styrene units in random copolymers of styrene and methyl methacrylate, shown by tim radical yidds G(R ) derived from the ESR spectra, (a) Experimental values for y irradiation at 77 K (b) experimental values for r>in ation at 300 K. The lines correspond to the G(R ) values for the copolymers calculated from the G(R ) values for poly(mediyl methacrylate) and polystyreiK based on the additivity of electron densities... [Pg.272]


See other pages where Mediyl Radical is mentioned: [Pg.1320]    [Pg.1320]    [Pg.1320]    [Pg.1320]    [Pg.1320]    [Pg.1320]    [Pg.231]    [Pg.57]    [Pg.218]    [Pg.782]    [Pg.111]   
See also in sourсe #XX -- [ Pg.160 ]




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