16681-34-8Relevant academic research and scientific papers
Substituent Effects of Alkyl Groups on the Decomposition of tert-Alkyl Peroxides
Matsuyama, Kazuo,Sugiura, Takashi,Minoshima, Yoshihiko
, p. 5520 - 5525 (1995)
In order to clarify substituent effects of alkyl groups on the decomposition of various tert-alkyl peroxides (RCMe2OOR'), the decomposition of 1-methoxy-1-(tert-alkylperoxy)cyclohexanes 3 and 1,1-bis(tert-alkylperoxy)cyclohexanes 4 has been studied by use of methods of kinetics and product analysis in cumene with the range of temperatures from 80-110 deg C and compared with those of the corresponding peroxyesters (1; R' = CO-t-Bu) and dialkyl peroxides (2; R' = t-Bu).The decomposition rates for each peroxide series decrease in the following order: 1 >> 3 > 4 >> 2.The decomposition rate for the series of peroxides 1 decreases in the following order: R = t-BuCH2 >> i-Pr >> Et > Pr > Me.But, for the series of peroxides 2, 3, and 4, R = t-BuCH2 >> i-Pr >> Pr > Et >> Me.The decompositon rate is expressed by a modified Taft equation : log kd = ρ*ΣρCH2R* + nh + C, which contains both inductive and C-H hyperconjugation effects of alkyl groups.On the basis of the isokinetic relationship of the activation parameters, the Taft equation, and the decomposition products, the decomposition mechanism via an polar activation complex having a slightly stretched Cα - Cβ bond neighboring to the peroxy oxygen atom is suggested and the abnormal behavior of neopentyl group is discussed.
Acid-Catalyzed Activation of Peroxyketals: Tunable Radical Initiation at Ambient Temperature and below
Schweitzer-Chaput, Bertrand,Boess, Esther,Klussmann, Martin
supporting information, p. 4944 - 4947 (2016/10/18)
This study details how peroxyketals, commercially available thermal initiators, and structurally related peroxides are activated in the presence of an acid catalyst to generate radicals at room temperature and below. This simple combination of two substrates was shown to efficiently initiate a variety of radical processes. This phenomenon is rationalized by the acid-catalyzed in situ formation of highly unstable alkenyl peroxides which readily decompose into initiating radical species.
