Di-/er/-butyl peroxide

Alkyl radicals can be obtained by abstraction of a hydrogen atom from an alkyl group by another radical. This method was utilized for the generation of benzyl radicals from toluene with iert-butoxy radical obtained on heating di- er -butyl peroxide. BenzoyP and carboxymethyP radicals have also been obtained by this method. The reaction gives rise to a complex mixture of products and therefore is of rather limited use. 

Cobaltic acetate oxidises /er/-butyl hydroperoxide to a mixture of /err-butanol, di- er/-butyl peroxide and oxygen with essentially second-order kinetics . The reaction does not involve 0-0 fission, the mechanism suggested being... 

At pressures above 6000 bar, free radical polymerisation sometimes proceeded explosively [ 1 ]. The parameters were determined in a batch reactor for thermal runaway polymerisation of acrylonitrile initiated by azoisobutyronitrile, dibenzoyl peroxide or di-/er/-butyl peroxide [2],... 

Method laser flash photolysis, if not otherwise mentioned. Solvent 2 1 (v/v) di-ferf-butyl peroxide/benzene or 1 4 (v/v) di-/er/-butyl peroxide/isooctane. 

Di-/er/-butyl peroxide (ter/-butyl peroxide) [110-05-4] M 146.2, d 0.794, n 1.389, Washed with aqueous AgNOs to remove olefinic impurities, water and dried (MgSOa). Freed from /err-butyl hydroperoxide by passage through an alumina column [Jackson et al. J Am Chem Soc 107 208 7985], and if necessary two high vacuum distns from room temp to a liquid-air trap [Offenbach and Tobolsky J Am Chem Soc 79 278 1957]. The necessary protection from EXPLOSION should be used. 

The decomposition of di- er -butyl peroxide in the presence of diethyl phosphite and an aromatic substrate leads to free-radical phosphination, Eqs. (43) and (44). 

Methane- and ethanethiol underwent addition to methylenecyclopropane to give the respective (alkylsulfanylmethyl)cyclopropane 1 a, b in 63 and 44% yield. Benzenethiol reacted with the methyl ester of Feist s acid in the same manner to give 1 c, but required the addition of di-/er/-butyl peroxide. ... 

The first study on the structure of imidoyl radicals dates back to 1973 [11], when Danen described the ESR spectra of the radicals obtained by irradiation of cyclopropane solutions of some aldimines and di-/er -butyl peroxide. On the basis of the low g-values (2.0016) and the jff-hydrogen hyperfine splittings, the authors claimed that imidoyls are cr-radicals with a non-linear arrangement about the N=C-C bond. The facile abstraction of the aldiminic hydrogen, and hence the remarkable stabilization of imidoyl radicals, was explained by the intervention of the mesomeric forms 3a and 3b (Scheme 5), in which the unpaired electron is stabilized by interaction with the lone pair on nitrogen. 

Anthrylphosphonic add 167 Anthracene (53.6 g, 0.3 mole), diethyl phosphite (170 ml, 1.33 moles), and di-/er/-butyl peroxide (30.1 ml, 0.168 mole) are heated for 4 h at 150°, whereafter much (120 ml) of the diethyl phosphite is recovered by distillation in a vacuum. The residue is treated with water (200 ml), collected, washed with water, and, for hydrolysis, heated under reflux for 72 h with a mixture of ethanol (500 ml) and concentrated hydrochloric acid (150 ml). The resulting solution is evaporated and the solid residue is heated with 5% aqueous potassium hydroxide (500 ml). Filtration and acidification then precipitate a yellow crude product (38.6 g), m.p. 279-282°, which is washed with water. For purification this product (6.5 g) is stirred with charcoal in a solution of sodium acetate (10 g) in water (100 ml) for 0.5 h at 70°. Filtration and acidification precipitate the white acid which, after drying at 120° in a vacuum, has m.p. 282-283° (dec.) (6.2 g). 

The only reactions of dialkyl peroxides with phosphites reported (205,299,300) are for di-a-cumyl and di- er -butyl peroxides. The isolation of bi-a-cumyl as a major product of the former reaction is indicative of a homolytic process formulated by Walling and Rabinowitz as ... 

A variety of other oxidizing agents, including dibenzoyl peroxide (253, 266, 267), acetyl benzoyl peroxide (266), di-/er/-butyl peroxide (141),... 

One additional example of this reaction can be used to illustrate an important difference between addition reactions that proceed by radicals and those that proceed by carbocation intermediates. The reaction of 3-methyl-l-pentene and HBr in the presence of di- er -butyl peroxide (MegCOOCMes, another peroxide radical precursor) leads to 157 via a radical chain mechanism and radical intermediate... 

An iron-catalyzed decarboxylative Csp3-Cjp2 coupling of proline derivatives and naphthols has been described. Iron(II) sulfate is used as catalyst and di-/er/-butyl peroxide functions as oxidant (Scheme 4-261). ... 

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