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Rearrangements of free radicals

The identification of the structure of this complex can give the data on the radical r. These data are especially fruitful for the analysis of mechanisms of intramolecular rearrangements of free radicals of different types, in particular, peroxide radicals (=Si-0)2Si(r)(0-0 ), r — H, CH3, and C2H5. The formation of products of peroxide radicals decomposition - H atom or OH radicals - was detected experimentally. [Pg.333]

AH the existing evidence indicates quite strongly that, although rearrangement of free radicals occasionally happens, it is not very common and does not involve simple alkyl radicals. [Pg.108]

Fiedorow, R Pasikowska, M. Koroniak, H. Mazurkiewicz, R. Zawadiak, J. Orlinska, B. Stec, Z. Grymel, M. Rearrangements of free radicals during 2-naphthol synthesis from 2-isopropylnaphtha-lene. Theochemlfm, 758, 75-79. [Pg.245]

Intramolecular rearrangements of free radicals are not nearly so common as those of carbo-cations. In fact, the most important rearrangements of free radicals are those associated with free radical "clocks", as discussed in Section 8.8.8 and listed in Table 8.7. Here we describe a few other rearrangements of radical. systems. [Pg.683]

SECTION 12.7. REARRANGEMENT AND FRAGMENTATION REACTIONS OF FREE RADICALS... [Pg.719]

Rearrangement and Fragmentation Reactions of Free Radicals 12.7.1. Rearrangement Reactions... [Pg.719]

Homolytic decompn when heated or irradiated with prodn of free radicals for org synthesis difficult to hydrolyze and reduce rearrangement crosslinking and polymerization polymeric peroxides are thick liqs or amorph wh powds used as polymerization catalysts... [Pg.679]

In this chapter, we discuss free-radical substitution reactions. Free-radical additions to unsaturated compounds and rearrangements are discussed in Chapters 15 and 18, respectively. In addition, many of the oxidation-reduction reactions considered in Chapter 19 involve free-radical mechanisms. Several important types of free-radical reactions do not usually lead to reasonable yields of pure products and are not generally treated in this book. Among these are polymerizations and high-temperature pyrolyses. [Pg.896]

Tetralin has been shown to undergo thermal dehydrogenation to naphthalene and rearrangement to methyl indan in either the absence or presence of free radical acceptors [ 1, 2]. The presence of free radical acceptors usually accelerates the rearrangement reaction. Even with alkylated Tetralins>... [Pg.364]

Sym-octahydrophenanthrene (HgPh) would be expected to follow the same rearrangement-dehydrogenation reactions as Tetralin, except with more isomer and product possibilities. The reactions shown in Figure 1 illustrate the many structures expected from sym-HgPh in the presence of free radical acceptors. Unlike Tetralin, hydrophenanthrenes have multiple structures which each, in turn, form various isomers. The amounts of these isomers are dependent upon the type of hydrogen-transfer reactions and the environment of the system. [Pg.365]

These rearrangements occur through intermediate formation of free radicals. D. Barton reaction... [Pg.232]

Very little skeletal rearrangement occurs via pyrolysis, a fact inherent in the failure of free radicals to readily isomerize by hydrogen atom or alkyl group migration. As a result, little branched alkanes are produced. Aromatization through the dehydrogenation of cyclohexanes and condensation to form polynuclear aromatics can take place. Additionally, olefin polymerization also can occur as a secondary process. [Pg.34]

In gas-phase hydrobromination, where a radical mechanism is operative, the bromine atom always adds to the central carbon atom of the allenic system. As a result, vinylic bromides are formed through the stable allylic radical. In the solution phase under ionic addition conditions, either the vinylic or the allylic cation may be the intermediate, resulting in nonselective hydrobromination. Allylic rearrangement or free-radical processes may also affect product distributions. [Pg.295]


See other pages where Rearrangements of free radicals is mentioned: [Pg.191]    [Pg.107]    [Pg.107]    [Pg.107]    [Pg.107]    [Pg.168]    [Pg.191]    [Pg.107]    [Pg.107]    [Pg.107]    [Pg.107]    [Pg.168]    [Pg.144]    [Pg.706]    [Pg.65]    [Pg.68]    [Pg.895]    [Pg.1421]    [Pg.866]    [Pg.706]    [Pg.82]    [Pg.806]    [Pg.825]    [Pg.25]    [Pg.210]    [Pg.11]    [Pg.46]    [Pg.217]    [Pg.615]    [Pg.807]    [Pg.826]    [Pg.98]    [Pg.678]    [Pg.1069]    [Pg.1103]    [Pg.206]    [Pg.586]   
See also in sourсe #XX -- [ Pg.719 , Pg.720 ]

See also in sourсe #XX -- [ Pg.194 , Pg.1051 , Pg.1064 , Pg.1065 , Pg.1066 , Pg.1100 , Pg.1101 , Pg.1102 , Pg.1151 , Pg.1152 , Pg.1153 ]

See also in sourсe #XX -- [ Pg.545 , Pg.546 ]

See also in sourсe #XX -- [ Pg.704 , Pg.705 ]

See also in sourсe #XX -- [ Pg.719 , Pg.720 ]




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Free radical rearrangements

Radical rearrangments

Radicals rearrangements

Rearrangement Reactions of Free Radicals

Rearrangement and Fragmentation Reactions of Free Radicals

Rearrangements of radicals

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