644-31-5Relevant academic research and scientific papers
Palladium-catalyzed ortho-functionalization of azoarenes with aryl acylperoxides
Qian, Cheng,Lin, Dongen,Deng, Yuanfu,Zhang, Xiao-Qi,Jiang, Huanfeng,Miao, Guang,Tang, Xihao,Zeng, Wei
, p. 5866 - 5875 (2014/08/05)
With the aid of an azo directing group, Pd-catalyzed ortho-sp2 C-H bond activation/functionalization of azoarenes with aryl acyl peroxides has been explored. This transformation provides easy access to regioselectively introducing acyloxyl and aryl groups into azoarenes by simply changing the reaction temperature and solvent. This journal is the Partner Organisations 2014.
Stability of 1:1 and 2:1 α-cyclodextrin-p-nitrophenyl acetate complexes and the effect of α-cyclodextrin on acyl transfer to peroxide anion nucleophiles
Davies, D. Martin,Deary, Michael E.
, p. 1027 - 1034 (2007/10/03)
The presence of a rate maximum rather than simple saturation-type kinetics in a study of the effect of α-cyclodextrin on the hydrolysis of p-nitrophenyl acetate (PNPA) indicates that α-cyclodextrin forms not only 1:1 but also 2:1 complexes with PNPA. This is confirmed using a spectrophotometric method to determine binding constants directly for PNPA, giving values of 46 ± 9 and 66 ± 19 dm3 mol-1 for the first and second binding steps respectively. These results contradict the majority of literature studies of this reaction in which it is assumed that only a 1:1 complex is formed. Formation of a 1 :1 complex with cyclodextrin increases the reactivity of PNPA towards hydrolysis, as has been widely reported, whereas the addition of a second cyclodextrin molecule to the complex results in the PNPA taking up a less reactive configuration. The effect of α-cyclodextrin on the reaction between PNPA and the anions of hydrogen peroxide, peroxomonosulfate, peracetic acid, perbenzoic acid, 4-methylperbenzoic acid, 4-nitroperbenzoic acid, 4-sulfonatoperbenzoic acid, 3-chloroperbenzoic acid and 4-tert-butylperbenzoic acid is described. Linear free energy studies for transition state stabilisation of the reaction by one molecule of cyclodextrin reveal that the main pathway involves the bound PNPA reacting with free peroxide anions, although for m-chloroperbenzoic acid an alternative pathway may be significant. This is in contrast to the behaviour observed for the α-cyclodextrin-mediated reaction of the molecular acid form of these peroxides with a series of aryl alkyl sulfides in which the main pathway involves nucleophilic attack of the free sulfide on the cyclodextrin-peracid complex. With the exception of the m-chloroperbenzoic acid anion there is no evidence of transition state stabilisation of the title reaction by two molecules of cyclodextrin.
POLARISATION NUCLEAIRE INDUITE CHIMIQUEMENT: ETUDE COMPARATIVE DE LA DECOMPOSITION THERMIQUE ET PHOTOCHIMIQUE DE PEROXYDES D'ACYLE BENZOYLE
Nedelec, J. Y.,Lefort, D.
, p. 3199 - 3204 (2007/10/02)
A comparative CIDNP study of the thermal and photochemical decomposition of acyl benzoyl peroxides PhCO2O2CR (R=methyl and isobutyl) has provided an explanation of the effect of the mode of initiation on the course of the decomposition of this class of peroxides and on the product distribution.The observed variations result from an important decrease (from 1E-8 sec to less than 1E-10 sec) in the lifetime of the benzoyloxy radical on changing from thermal to photochemical initiation.
